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1.
BMC Nephrol ; 25(1): 82, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443920

RESUMO

OBJECTIVE: The objective of this systematic review and meta-analysis was to assess the value of uric acid in predicting acute kidney injury caused by traumatic rhabdomyolysis. METHODS: The search was conducted in MEDLINE, Scopus, Embase and Web of Science until November 1, 2023. Based on the inclusion and exclusion criteria, the articles were included by two independent researchers. Data regarding study design, patient characteristics, number of patients with and without AKI, mean and SD of uric acid and prognostic characteristics of uric acid were extracted from relevant studies. STATA version 17.0 was used to compute pooled measures of standardized mean differences, odds ratios, and diagnostic accuracy. I2 and chi-square tests were used to assess heterogeneity between studies. RESULTS: We found 689 non-redundant studies, 44 of them were potentially relevant. Six articles met the inclusion criteria and were included in the review. The results of the meta-analysis confirmed that there was a significant correlation between serum uric acid levels and the occurrence of AKI (SMD = 1.61, 95% CI = 0.69 to 2.54, I2 = 96.94%; p value = 0.001). There were no significant publication biases. CONCLUSION: According to this meta-analysis, uric acid levels could be considered as a predictor of acute kidney injury following traumatic rhabdomyolysis.


Assuntos
Injúria Renal Aguda , Rabdomiólise , Humanos , Ácido Úrico , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Razão de Chances , Projetos de Pesquisa , Rabdomiólise/complicações
2.
IEEE Trans Pattern Anal Mach Intell ; 42(9): 2321-2326, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31535981

RESUMO

We study the accuracy of triangulation in multi-camera systems with respect to the number of cameras. We show that, under certain conditions, the optimal achievable reconstruction error decays quadratically as more cameras are added to the system. Furthermore, we analyze the error decay-rate of major state-of-the-art algorithms with respect to the number of cameras. To this end, we introduce the notion of consistency for triangulation, and show that consistent reconstruction algorithms achieve the optimal quadratic decay, which is asymptotically faster than some other methods. Finally, we present simulations results supporting our findings. Our simulations have been implemented in MATLAB and the resulting code is available in the supplementary material, which can be found on the Computer Society Digital Library at http://doi.ieeecomputersociety.org/10.1109/TPAMI.2019.2939530.

3.
Sci Rep ; 9(1): 17372, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31758075

RESUMO

Electromagnetic Time Reversal (EMTR) has been used to locate different types of electromagnetic sources. We propose a novel technique based on the combination of EMTR and Machine Learning (ML) for source localization. We show for the first time that ML techniques can be used in conjunction with EMTR to reduce the required number of sensors to only one for the localization of electromagnetic sources in the presence of scatterers. In the EMTR part, we use 2D-FDTD method to generate 2D profiles of the vertical electric field as RGB images. Next, in the ML part, we take advantage of transfer learning techniques by using the pretrained VGG-19 Convolutional Neural Network (CNN) as the feature extractor tool. To the best of our knowledge, this is the first time that the knowledge of pretrained CNNs is applied to simulation-generated images. We demonstrate the skill of the developed methodology in localizing two kinds of electromagnetic sources, namely RF sources with a bandwidth of 0.1-10 MHz and lightning impulses. For the localization of lightning, based on the experimental recordings in the Säntis region, the new approach enables accurate 2D lightning localization using only one sensor, as opposed to current lightning location systems that need at least two sensors to operate.

4.
Materials (Basel) ; 12(20)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640278

RESUMO

In the present study, Mg nanocomposites with a high volume fraction (10 vol %) of SiC particles were fabricated by two approaches: mechanical milling and mixing, followed by the powder consolidation steps, including isostatic cold pressing, sintering, and extrusion. A uniform distribution of the high content SiC particles in a fully dense Mg matrix with ultrafine microstructure was successfully achieved in the mechanically milled composites. The effect of nano- and submicron-sized SiC particles on the microstructure and mechanical properties of the nanocomposites was evaluated. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), and X-ray diffractometry (XRD) were used to characterize microstructures of the milled and mixed composites. Mechanical behavior of the Mg composites was studied under nanoindentation and compressive loading to understand the effects the microstructural modification on the strength and ductility of the Mg/SiC composites. The mechanical properties of the composites showed a significant difference regarding the size and distribution of SiC particles in the Mg matrix. The enhanced strength and superior ductility achieved in the mechanically milled Mg composites are mainly ascribed to the effective load transfer between matrix and SiC particles, grain refinement of the matrix, and strengthening effects of the nano- and submicron-sized SiC particles.

5.
Galen Med J ; 7: e936, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-34466419

RESUMO

BACKGROUND: Design, formulation and physicochemical evaluation of dimenhydrinate 25 mg oral tablets that disintegrate in oral cavity in a proper time. This product is easy to use for babies, geriatrics and people who have difficulty in swallowing. MATERIALS AND METHODS: 31 formulations were designed in 3 categories via Design-Expert software version 7. Group 1 consist of super-disintegrating bases, group 2 consist of effervescent bases and group 3 consist of super-disintegrating and effervescent bases together. Proposed by DesignExpert software, the optimum formulations were selected in each category and the tablets were produced by direct compression method. Tablets evaluated by friability, thickness, hardness, weight variation, drug content, content uniformity, disintegration time, wetting time, dissolution and moisture uptake tests. RESULTS: The angle of repose and compressibility index of formulations were in the range of 24.65-29.08 and 5.02-9.01 % respectively. Thickness, hardness, wetting time, friability and content uniformity of formulations were in the range of 3.36-3.84 mm, 33.25-38.03 N, 19-37 seconds, 0.31-0.42 % and 96.44-99.02 % respectively. Disintegration time of the groups 1, 2 and 3 were in the range of 16-70, 47-72 and 12-35 seconds respectively. CONCLUSION: Mixture of powders and orally dispersible tablets passed all tests. The results showed that formulations containing both of super-disintegrants and effervescent bases had better disintegration time compare to other formulations.

6.
J Biomed Mater Res A ; 105(7): 2047-2055, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28296041

RESUMO

With the ever-increasing use of carbon nanotubes (CNTs) in health-related and engineering applications, the hazardous risks of this material have become a major concern. It is well known that CNTs accumulate with cytotoxic and genotoxic levels within vital organs. It has also been shown that treating cell cultures with CNTs resulted in cell-cycle arrest and increased apoptosis/necrosis. The goal of this pilot study is to perform a comprehensive comparative study on the toxicity of single-wall (SW) and multiwall (MW) CNTs in rat skin cells. Our results confirm a dose-dependent toxicity of SWCNTs and MWCNTs due to the loss of mitochondrial activity, increase in mitochondrial reactive oxygen species (ROS) formation, and mitochondrial membrane potential collapse before mitochondrial swelling. Moreover, disturbance in the oxidative phosphorylation is observed by a decrease in ATP level. These events induced the release of cytochrome c via outer membrane rupture or MPT pore opening and subsequently programmed cell death of all doses compared to control group. Our results demonstrate that although MWCNTs can be very toxic, SWCNTs cause more mitochondrial damage to the cells. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2047-2055, 2017.


Assuntos
Apoptose , Pontos de Checagem do Ciclo Celular , Mitocôndrias/metabolismo , Nanotubos de Carbono/química , Estresse Oxidativo , Animais , Masculino , Camundongos , Ratos
7.
Nanoscale ; 9(4): 1356-1392, 2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28067384

RESUMO

Nanocages (NCs) have emerged as a new class of drug-carriers, with a wide range of possibilities in multi-modality medical treatments and theranostics. Nanocages can overcome such limitations as high toxicity caused by anti-cancer chemotherapy or by the nanocarrier itself, due to their unique characteristics. These properties consist of: (1) a high loading-capacity (spacious interior); (2) a porous structure (analogous to openings between the bars of the cage); (3) enabling smart release (a key to unlock the cage); and (4) a low likelihood of unfavorable immune responses (the outside of the cage is safe). In this review, we cover different classes of NC structures such as virus-like particles (VLPs), protein NCs, DNA NCs, supramolecular nanosystems, hybrid metal-organic NCs, gold NCs, carbon-based NCs and silica NCs. Moreover, NC-assisted drug delivery including modification methods, drug immobilization, active targeting, and stimulus-responsive release mechanisms are discussed, highlighting the advantages, disadvantages and challenges. Finally, translation of NCs into clinical applications, and an up-to-date assessment of the nanotoxicology considerations of NCs are presented.


Assuntos
Sistemas de Liberação de Medicamentos , Nanoestruturas/química , Nanoestruturas/toxicidade , Nanomedicina Teranóstica , Animais , Materiais Biocompatíveis , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Ouro , Humanos , Neoplasias/tratamento farmacológico
8.
ACS Appl Mater Interfaces ; 8(33): 21107-33, 2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27349465

RESUMO

Smart drug delivery systems (DDSs) have attracted the attention of many scientists, as carriers that can be stimulated by changes in environmental parameters such as temperature, pH, light, electromagnetic fields, mechanical forces, etc. These smart nanocarriers can release their cargo on demand when their target is reached and the stimulus is applied. Using the techniques of nanotechnology, these nanocarriers can be tailored to be target-specific, and exhibit delayed or controlled release of drugs. Temperature-responsive nanocarriers are one of most important groups of smart nanoparticles (NPs) that have been investigated during the past decades. Temperature can either act as an external stimulus when heat is applied from the outside, or can be internal when pathological lesions have a naturally elevated termperature. A low critical solution temperature (LCST) is a special feature of some polymeric materials, and most of the temperature-responsive nanocarriers have been designed based on this feature. In this review, we attempt to summarize recent efforts to prepare innovative temperature-responsive nanocarriers and discuss their novel applications.


Assuntos
Nanopartículas , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Polímeros , Temperatura
9.
J Vasc Nurs ; 27(4): 103-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19914571

RESUMO

The removal of the saphenous veins in coronary artery bypass graft (CABG) surgery may cause leg edema. Compression therapy is often used to prevent postoperative edema. The objective of this study was to compare the efficacy of medical compression stocking (TED) and elastic bandage-type on donor limbs after CABG. The peripheries of lower limbs were measured at four regions (A: end of tarsal bones, H: heel , B: immediately above the ankle, C: largest circumference of the calf) at admission in 295 patients how CABG candidates and differences in these measurement points at discharge compared to measurements at admission time were calculated. The difference was considered as a measure of the effectiveness of two types of compression to prevent postoperative edema in donor limbs after CABG. The alterations of 396 donor limbs of 295 patients were examined after CABG at admission and discharge time. In 101 patients veins for graft were taken from both lower limbs. After analysis, if subjects had worn TED stockings, the peripheries of donor limbs at discharge were less than at admission time in the A and H regions compared to elastic bandage group (P(A) = 0/009), (P(H) = 0/012). The conclusion reached was that using the kind of knee length compression stocking (TED stocking , Kendall Co.) is more effective edema at foot and heel regions in donor limbs after CABG than elastic bandages.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Edema/prevenção & controle , Meias de Compressão , Bandagens , Desenho de Equipamento , Feminino , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Análise de Regressão
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