Nanoemulsion: A Review on Mechanisms for the Transdermal Delivery of Hydrophobic and Hydrophilic Drugs

Nanoemulsions (NEs) are colloidal dispersions of two immiscible liquids, oil and water, in which one is dispersed in the other with the aid of a surfactant/co-surfactant mixture, either forming oil-in-water (o/w) or water-in-oil (w/o) nanodroplets systems, with droplets 20–200 nm in size. NEs are easy to prepare and upscale, and they show high variability in their components. They have proven to be very viable, non-invasive, and cost-effective nanocarriers for the enhanced transdermal delivery of a wide range of active compounds that tend to metabolize heavily or suffer from undesirable side effects when taken orally. In addition, the anti-microbial and anti-viral properties of NE components, leading to preservative-free formulations, make NE a very attractive approach for transdermal drug delivery. This review focuses on how NEs mechanistically deliver both lipophilic and hydrophilic drugs through skin layers to reach the blood stream, exerting the desired therapeutic effect. It highlights the mechanisms and strategies executed to effectively deliver drugs, both with o/w and w/o NE types, through the transdermal way. However, the mechanisms reported in the literature are highly diverse, to the extent that a definite mechanism is not conclusive.

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Using a Microwave Sensor as an Online Indicator of Neurological Impairment during Surgical Procedures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.368 ◽

2013 ◽

Vol 543 ◽

pp. 368-372 ◽

Cited By ~ 10

Author(s):

Jung H. Goh ◽

Alex Mason ◽

Mark Field ◽

Paul Browning ◽

Ahmed Al-Shamma'a

Keyword(s):

Cost Effective ◽

Neurological Impairment ◽

Treatment Regimes ◽

Non Invasive ◽

Microwave Sensor ◽

Wide Range ◽

Invasive Method ◽

Aortic Aneurysm Surgery ◽

Online Methods

Lactate is known to be an indicator of neurological impairment during aortic aneurysm surgery. It is suggested that analysis of cerebrospinal fluid (CSF) removed during such surgery could provide useful information in this regard. Medical professionals find the prospect of online detection of such analytes exciting, as current practice is time consuming and leads to multiple invasive procedures. Advancing from the current laboratory based analysis techniques to online methods could provide the basis for improved treatment regimes, better quality of care, and enhanced resource efficiency within hospitals. Accordingly, this article considers the use of a low power microwave sensor to detect varying lactate concentrations. Microwave sensors provide a rapid non-invasive method of material analysis, which is robust, cost-effective, and has huge potential for a wide range of biomedical applications.

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Enhancing Permeation of Drug Molecules Across the Skin via Delivery in Nanocarriers: Novel Strategies for Effective Transdermal Applications

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.646554 ◽

2021 ◽

Vol 9 ◽

Author(s):

Yi-Qun Yu ◽

Xue Yang ◽

Xiao-Fang Wu ◽

Yi-Bin Fan

Keyword(s):

Drug Delivery ◽

Stratum Corneum ◽

Transdermal Delivery ◽

Transdermal Drug Delivery ◽

Hydrophilic Drugs ◽

Non Invasive ◽

Drug Molecules ◽

Systemic Side Effects ◽

Route Of Delivery ◽

Transdermal Route

The transdermal route of administration provides numerous advantages over conventional routes i.e., oral or injectable for the treatment of different diseases and cosmetics applications. The skin also works as a reservoir, thus deliver the penetrated drug for more extended periods in a sustained manner. It reduces toxicity and local irritation due to multiple sites for absorption and owes the option of avoiding systemic side effects. However, the transdermal route of delivery for many drugs is limited since very few drugs can be delivered at a viable rate using this route. The stratum corneum of skin works as an effective barrier, limiting most drugs’ penetration posing difficulty to cross through the skin. Fortunately, some non-invasive methods can significantly enhance the penetration of drugs through this barrier. The use of nanocarriers for increasing the range of available drugs for the transdermal delivery has emerged as a valuable and exciting alternative. Both the lipophilic and hydrophilic drugs can be delivered via a range of nanocarriers through the stratum corneum with the possibility of having local or systemic effects to treat various diseases. In this review, the skin structure and major obstacle for transdermal drug delivery, different nanocarriers used for transdermal delivery, i.e., nanoparticles, ethosomes, dendrimers, liposomes, etc., have been discussed. Some recent examples of the combination of nanocarrier and physical methods, including iontophoresis, ultrasound, laser, and microneedles, have also been discussed for improving the therapeutic efficacy of transdermal drugs. Limitations and future perspectives of nanocarriers for transdermal drug delivery have been summarized at the end of this manuscript.

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2D Color-Intensity Representation of Ultrasonic Thickness Gauge Measurements

Materials Evaluation ◽

10.32548/2020.me-04177 ◽

2020 ◽

pp. 1192-1198

Author(s):

M.S. Mohammad ◽

Tibebe Tesfaye ◽

Kim Ki-Seong

Keyword(s):

Cost Effective ◽

The Other ◽

Thickness Gauge ◽

Color Intensity ◽

Digital Readout ◽

Flat Surfaces ◽

Video Cameras ◽

Wide Range ◽

Cost Effective Alternative ◽

Ultrasonic Thickness

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.

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New Approach to Non-invasive Visualisation of Cardiac Function – Riskfree Test Can Provide Fast, Cost-effective Diagnosis

European Cardiology Review ◽

10.15420/ecr.2006.1.1t ◽

2006 ◽

Vol 2 (1) ◽

pp. 1

Author(s):

CardioMag Imaging

Keyword(s):

Cardiac Function ◽

Cost Effective ◽

New Approach ◽

Non Invasive ◽

Effective Diagnosis

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Role of Cardiac MRI in Detecting Familial Hypertrophic Cardiomyopathy: Review

Journal of Clinical and Health Sciences ◽

10.24191/jchs.v1i1.5846 ◽

2016 ◽

Vol 1 (1) ◽

pp. 4

Author(s):

Marymol Koshy ◽

Bushra Johari ◽

Mohd Farhan Hamdan ◽

Mohammad Hanafiah

Keyword(s):

Hypertrophic Cardiomyopathy ◽

Magnetic Resonance ◽

Genetic Disorder ◽

Familial Hypertrophic Cardiomyopathy ◽

Non Invasive ◽

Wide Range ◽

Proper Diagnosis ◽

Magnetic Resonance Imaging Mri ◽

Potential Use

Hypertrophic cardiomyopathy (HCM) is a global disease affecting people of various ethnic origins and both genders. HCM is a genetic disorder with a wide range of symptoms, including the catastrophic presentation of sudden cardiac death. Proper diagnosis and treatment of this disorder can relieve symptoms and prolong life. Non-invasive imaging is essential in diagnosing HCM. We present a review to deliberate the potential use of cardiac magnetic resonance (CMR) imaging in HCM assessment and also identify the risk factors entailed with risk stratification of HCM based on Magnetic Resonance Imaging (MRI).

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A novel use of contrast-enhanced ultrasound in uterine artery embolization

American Journal of Interventional Radiology ◽

10.25259/ajir_3_2020 ◽

2020 ◽

Vol 4 ◽

pp. 8

Author(s):

Jemianne Bautista Jia ◽

Eric Mastrolonardo ◽

Mateen Soleman ◽

Ilya Lekht

Keyword(s):

Uterine Artery Embolization ◽

Uterine Artery ◽

Imaging Modality ◽

Cost Effective ◽

Contrast Enhanced Ultrasound ◽

Artery Embolization ◽

Non Invasive ◽

Contrast Enhanced

Contrast-enhanced ultrasound (CEUS) is a cost-effective, quick, and non-invasive imaging modality that has yet to be incorporated in uterine artery embolization (UAE). We present two cases that demonstrate the utility of CEUS in UAE for the identification of uterine-ovarian collaterals which otherwise can result in ineffective fibroid treatment and non-target embolization.

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Review of Various Tasks Performed in the Preprocessing Phase of a Diabetic Retinopathy Diagnosis System

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405615666190219102427 ◽

2020 ◽

Vol 16 (4) ◽

pp. 397-426

Author(s):

Muhammad Nadeem Ashraf ◽

Muhammad Hussain ◽

Zulfiqar Habib

Keyword(s):

Diabetic Retinopathy ◽

Blood Vessels ◽

Early Stage ◽

Spherical Shape ◽

Cost Effective ◽

Lesion Detection ◽

Diabetic Patients ◽

Cad System ◽

Non Invasive ◽

Optic Discs

Diabetic Retinopathy (DR) is a major cause of blindness in diabetic patients. The increasing population of diabetic patients and difficulty to diagnose it at an early stage are limiting the screening capabilities of manual diagnosis by ophthalmologists. Color fundus images are widely used to detect DR lesions due to their comfortable, cost-effective and non-invasive acquisition procedure. Computer Aided Diagnosis (CAD) of DR based on these images can assist ophthalmologists and help in saving many sight years of diabetic patients. In a CAD system, preprocessing is a crucial phase, which significantly affects its performance. Commonly used preprocessing operations are the enhancement of poor contrast, balancing the illumination imbalance due to the spherical shape of a retina, noise reduction, image resizing to support multi-resolution, color normalization, extraction of a field of view (FOV), etc. Also, the presence of blood vessels and optic discs makes the lesion detection more challenging because these two artifacts exhibit specific attributes, which are similar to those of DR lesions. Preprocessing operations can be broadly divided into three categories: 1) fixing the native defects, 2) segmentation of blood vessels, and 3) localization and segmentation of optic discs. This paper presents a review of the state-of-the-art preprocessing techniques related to three categories of operations, highlighting their significant aspects and limitations. The survey is concluded with the most effective preprocessing methods, which have been shown to improve the accuracy and efficiency of the CAD systems.

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The Future of Plasma-Based Surface Engineering Techniques in Tribology (Keynote)

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-64180 ◽

2005 ◽

Cited By ~ 1

Author(s):

Allan Matthews ◽

Adrian Leyland

Keyword(s):

Surface Engineering ◽

Performance Enhancement ◽

Bulk Material ◽

Cost Savings ◽

Cost Effective ◽

Ceramic Coatings ◽

Performance Improvements ◽

Treatment Techniques ◽

Wide Range ◽

Macro Scale

Over the past twenty years or so, there have been major steps forward both in the understanding of tribological mechanisms and in the development of new coating and treatment techniques to better “engineer” surfaces to achieve reductions in wear and friction. Particularly in the coatings tribology field, improved techniques and theories which enable us to study and understand the mechanisms occurring at the “nano”, “micro” and “macro” scale have allowed considerable progress to be made in (for example) understanding contact mechanisms and the influence of “third bodies” [1–5]. Over the same period, we have seen the emergence of the discipline which we now call “Surface Engineering”, by which, ideally, a bulk material (the ‘substrate’) and a coating are combined in a way that provides a cost-effective performance enhancement of which neither would be capable without the presence of the other. It is probably fair to say that the emergence and recognition of Surface Engineering as a field in its own right has been driven largely by the availability of “plasma”-based coating and treatment processes, which can provide surface properties which were previously unachievable. In particular, plasma-assisted (PA) physical vapour deposition (PVD) techniques, allowing wear-resistant ceramic thin films such as titanium nitride (TiN) to be deposited on a wide range of industrial tooling, gave a step-change in industrial productivity and manufactured product quality, and caught the attention of engineers due to the remarkable cost savings and performance improvements obtained. Subsequently, so-called 2nd- and 3rd-generation ceramic coatings (with multilayered or nanocomposite structures) have recently been developed [6–9], to further extend tool performance — the objective typically being to increase coating hardness further, or extend hardness capabilities to higher temperatures.

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Gamma models for estimating the odds ratio for a skewed biomarker measured in pools and subject to errors

Biostatistics ◽

10.1093/biostatistics/kxz028 ◽

2019 ◽

Author(s):

Dane R Van Domelen ◽

Emily M Mitchell ◽

Neil J Perkins ◽

Enrique F Schisterman ◽

Amita K Manatunga ◽

...

Keyword(s):

Odds Ratio ◽

Adjusted Odds Ratio ◽

Lower Cost ◽

Cost Effective ◽

Ratio Estimation ◽

Statistical Efficiency ◽

Function Model ◽

Processing Error ◽

Wide Range ◽

Pooled Samples

SUMMARYMeasuring a biomarker in pooled samples from multiple cases or controls can lead to cost-effective estimation of a covariate-adjusted odds ratio, particularly for expensive assays. But pooled measurements may be affected by assay-related measurement error (ME) and/or pooling-related processing error (PE), which can induce bias if ignored. Building on recently developed methods for a normal biomarker subject to additive errors, we present two related estimators for a right-skewed biomarker subject to multiplicative errors: one based on logistic regression and the other based on a Gamma discriminant function model. Applied to a reproductive health dataset with a right-skewed cytokine measured in pools of size 1 and 2, both methods suggest no association with spontaneous abortion. The fitted models indicate little ME but fairly severe PE, the latter of which is much too large to ignore. Simulations mimicking these data with a non-unity odds ratio confirm validity of the estimators and illustrate how PE can detract from pooling-related gains in statistical efficiency. These methods address a key issue associated with the homogeneous pools study design and should facilitate valid odds ratio estimation at a lower cost in a wide range of scenarios.

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