scholarly journals Micro-optical Components for Bioimaging on Tissues, Cells and Subcellular Structures

Micromachines ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 405 ◽  
Author(s):  
Hui Yang ◽  
Yi Zhang ◽  
Sihui Chen ◽  
Rui Hao
Keyword(s):  
Imaging Techniques ◽  
Point Of Care ◽  
Biological Information ◽  
Optical Systems ◽  
Optical Components ◽  
Integrated Optical ◽  
Fast Development ◽  
Near Future

Bioimaging generally indicates imaging techniques that acquire biological information from living forms. Among different imaging techniques, optical microscopy plays a predominant role in observing tissues, cells and biomolecules. Along with the fast development of microtechnology, developing miniaturized and integrated optical imaging systems has become essential to provide new imaging solutions for point-of-care applications. In this review, we will introduce the basic micro-optical components and their fabrication technologies first, and further emphasize the development of integrated optical systems for in vitro and in vivo bioimaging, respectively. We will conclude by giving our perspectives on micro-optical components for bioimaging applications in the near future.

scholarly journals Detecting apoptosis as a clinical endpoint for proof of a clinical principle

2020 ◽  
Author(s):  
Piero Zollet ◽  
Timothy E.Yap ◽  
M Francesca Cordeiro
Keyword(s):  
Drug Development ◽  
Therapeutic Response ◽  
Imaging Techniques ◽  
Brain Diseases ◽  
Promising Strategy ◽  
Sight Loss ◽  
Apoptosis Detection ◽  
Novel Therapeutic Strategies

The transparent eye media represent a window through which to observe changes occurring in the retina during pathological processes. In contrast to visualising the extent of neurodegenerative damage that has already occurred, imaging an active process such as apoptosis has the potential to report on disease progression and therefore the threat of irreversible functional loss in various eye and brain diseases. Early diagnosis in these conditions is an important unmet clinical need to avoid or delay irreversible sight loss. In this setting, apoptosis detection is a promising strategy with which to diagnose, provide prognosis, and monitor therapeutic response. Additionally, monitoring apoptosis in vitro and in vivo has been shown to be valuable for drug development in order to assess the efficacy of novel therapeutic strategies both in the pre-clinical and clinical setting. Detection of Apoptosing Retinal Cells (DARC) technology is to date the only tool of its kind to have been tested in clinical trials, with other new imaging techniques under investigation in the fields of neuroscience, ophthalmology and drug development. We summarize the transitioning of techniques detecting apoptosis from bench to bedside, along with the future possibilities they encase.

scholarly journals Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4554
Author(s):  
Ralph-Alexandru Erdelyi ◽  
Virgil-Florin Duma ◽  
Cosmin Sinescu ◽  
George Mihai Dobre ◽  
Adrian Bradu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Radiation Dose ◽  
Imaging Techniques ◽  
Image Resolution ◽  
Optical Coherence ◽  
X Rays ◽  
High Quality ◽  
X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

scholarly journals Thrombus Imaging Using 3D Printed Middle Cerebral Artery Model and Preclinical Imaging Techniques: Application to Thrombus Targeting and Thrombolytic Studies

Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1207
Author(s):  
Andrea Vítečková Wünschová ◽  
Adam Novobilský ◽  
Jana Hložková ◽  
Peter Scheer ◽  
Hana Petroková ◽  
...  
Keyword(s):  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Imaging Techniques ◽  
Barium Sulphate ◽  
Flow Conditions ◽  
Preclinical Imaging ◽  
Blood Clots ◽  
3D Printed

Diseases with the highest burden for society such as stroke, myocardial infarction, pulmonary embolism, and others are due to blood clots. Preclinical and clinical techniques to study blood clots are important tools for translational research of new diagnostic and therapeutic modalities that target blood clots. In this study, we employed a three-dimensional (3D) printed middle cerebral artery model to image clots under flow conditions using preclinical imaging techniques including fluorescent whole-body imaging, magnetic resonance imaging (MRI), and computed X-ray microtomography (microCT). Both liposome-based, fibrin-targeted, and non-targeted contrast agents were proven to provide a sufficient signal for clot imaging within the model under flow conditions. The application of the model for clot targeting studies and thrombolytic studies using preclinical imaging techniques is shown here. For the first time, a novel method of thrombus labeling utilizing barium sulphate (Micropaque®) is presented here as an example of successfully employed contrast agents for in vitro experiments evaluating the time-course of thrombolysis and thus the efficacy of a thrombolytic drug, recombinant tissue plasminogen activator (rtPA). Finally, the proof-of-concept of in vivo clot imaging in a middle cerebral artery occlusion (MCAO) rat model using barium sulphate-labelled clots is presented, confirming the great potential of such an approach to make experiments comparable between in vitro and in vivo models, finally leading to a reduction in animals needed.

scholarly journals Current and Future Advancements of Raman Spectroscopy Techniques in Cancer Nanomedicine

2021 ◽  
Vol 22 (23) ◽  
pp. 13141
Author(s):  
Elisabetta Canetta
Keyword(s):  
Raman Spectroscopy ◽  
Imaging Techniques ◽  
Rapid Development ◽  
Surface Enhanced Raman Spectroscopy ◽  
Cancer Diagnostics ◽  
Raman Signal ◽  
Therapeutic Effects ◽  
Cancer Nanomedicine

Raman scattering is one of the most used spectroscopy and imaging techniques in cancer nanomedicine due to its high spatial resolution, high chemical specificity, and multiplexity modalities. The flexibility of Raman techniques has led, in the past few years, to the rapid development of Raman spectroscopy and imaging for nanodiagnostics, nanotherapy, and nanotheranostics. This review focuses on the applications of spontaneous Raman spectroscopy and bioimaging to cancer nanotheranostics and their coupling to a variety of diagnostic/therapy methods to create nanoparticle-free theranostic systems for cancer diagnostics and therapy. Recent implementations of confocal Raman spectroscopy that led to the development of platforms for monitoring the therapeutic effects of anticancer drugs in vitro and in vivo are also reviewed. Another Raman technique that is largely employed in cancer nanomedicine, due to its ability to enhance the Raman signal, is surface-enhanced Raman spectroscopy (SERS). This review also explores the applications of the different types of SERS, such as SERRS and SORS, to cancer diagnosis through SERS nanoprobes and the detection of small-size biomarkers, such as exosomes. SERS cancer immunotherapy and immuno-SERS (iSERS) microscopy are reviewed.

scholarly journals Gold Nanoparticle-Based Fluorescent Theranostics for Real-Time Image-Guided Assessment of DNA Damage and Repair

2019 ◽  
Vol 20 (3) ◽  
pp. 471 ◽  
Author(s):  
Shriya S. Srinivasan ◽  
Rajesh Seenivasan ◽  
Allison Condie ◽  
Stanton L. Gerson ◽  
Yanming Wang ◽  
...  
Keyword(s):  
Molecular Imaging ◽  
Real Time ◽  
Targeted Delivery ◽  
Specific Binding ◽  
Imaging Techniques ◽  
Cancer Cell Line ◽  
Molecular Probe ◽  
Biodistribution Studies

Chemotherapeutic dosing, is largely based on the tolerance levels of toxicity today. Molecular imaging strategies can be leveraged to quantify DNA cytotoxicity and thereby serve as a theranostic tool to improve the efficacy of treatments. Methoxyamine-modified cyanine-7 (Cy7MX) is a molecular probe which binds to apurinic/apyrimidinic (AP)-sites, inhibiting DNA-repair mechanisms implicated by cytotoxic chemotherapies. Herein, we loaded (Cy7MX) onto polyethylene glycol-coated gold nanoparticles (AuNP) to selectively and stably deliver the molecular probe intravenously to tumors. We optimized the properties of Cy7MX-loaded AuNPs using optical spectroscopy and tested the delivery mechanism and binding affinity using the DLD1 colon cancer cell line in vitro. A 10:1 ratio of Cy7MX-AuNPs demonstrated a strong AP site-specific binding and the cumulative release profile demonstrated 97% release within 12 min from a polar to a nonpolar environment. We further demonstrated targeted delivery using imaging and biodistribution studies in vivo in an xenografted mouse model. This work lays a foundation for the development of real-time molecular imaging techniques that are poised to yield quantitative measures of the efficacy and temporal profile of cytotoxic chemotherapies.

scholarly journals A Review of Neurotransmitters Sensing Methods for Neuro-Engineering Research

2019 ◽  
Vol 9 (21) ◽  
pp. 4719 ◽  
Author(s):  
Shimwe Dominique Niyonambaza ◽  
Praveen Kumar ◽  
Paul Xing ◽  
Jessy Mathault ◽  
Paul De Koninck ◽  
...  
Keyword(s):  
Imaging Techniques ◽  
Ongoing Research ◽  
Engineering Research ◽  
Detection Techniques ◽  
In Vivo Detection ◽  
Low Concentrations ◽  
The Subject ◽  
The Brain

Neurotransmitters as electrochemical signaling molecules are essential for proper brain function and their dysfunction is involved in several mental disorders. Therefore, the accurate detection and monitoring of these substances are crucial in brain studies. Neurotransmitters are present in the nervous system at very low concentrations, and they mixed with many other biochemical molecules and minerals, thus making their selective detection and measurement difficult. Although numerous techniques to do so have been proposed in the literature, neurotransmitter monitoring in the brain is still a challenge and the subject of ongoing research. This article reviews the current advances and trends in neurotransmitters detection techniques, including in vivo sampling and imaging techniques, electrochemical and nano-object sensing techniques for in vitro and in vivo detection, as well as spectrometric, analytical and derivatization-based methods mainly used for in vitro research. The document analyzes the strengths and weaknesses of each method, with the aim to offer selection guidelines for neuro-engineering research.

scholarly journals Promising Recent Strategies with Potential Clinical Translational Value to Combat Antibacterial Resistant Surge

Medicines ◽  
2019 ◽  
Vol 6 (1) ◽  
pp. 21 ◽  
Author(s):  
Partha Karmakar ◽  
Vishwanath Gaitonde
Keyword(s):  
Small Molecule ◽  
Multiple Drug Resistance ◽  
Resistance Mechanism ◽  
Multiple Drug ◽  
Antibacterial Efficacy ◽  
Small Particles ◽  
Near Future ◽  
Metal Polymer

Multiple drug resistance (MDR) for the treatment of bacterial infection has been a significant challenge since the beginning of the 21st century. Many of the small molecule-based antibiotic treatments have failed on numerous occasions due to a surge in MDR, which has claimed millions of lives worldwide. Small particles (SPs) consisting of metal, polymer or carbon nanoparticles (NPs) of different sizes, shapes and forms have shown considerable antibacterial effect over the past two decades. Unlike the classical small-molecule antibiotics, the small particles are less exposed so far to the bacteria to trigger a resistance mechanism, and hence have higher chances of fighting the challenge of the MDR process. Until recently, there has been limited progress of clinical treatments using NPs, despite ample reports of in vitro antibacterial efficacy. In this review, we discuss some recent and unconventional strategies that have explored the antibacterial efficacy of these small particles, alone and in combination with classical small molecules in vivo, and demonstrate possibilities that are favorable for clinical translations in near future.

scholarly journals In Vitro and In Vivo Studies of a Rapid and Selective Breath Test for Tuberculosis Based upon Mycobacterial CO Dehydrogenase

mBio ◽  
2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Mamoudou Maiga ◽  
Seong Won Choi ◽  
Viorel Atudorei ◽  
Mariama C. Maiga ◽  
Zachary D. Sharp ◽  
...  
Keyword(s):  
Breath Test ◽  
Point Of Care ◽  
In Vivo Studies ◽  
Co Dehydrogenase ◽  
Preclinical Development ◽  
Breath Tests ◽  
Monitoring Therapy ◽  
Effective Diagnosis

ABSTRACTOne of the major hurdles in treating tuberculosis (TB) is the time-consuming and difficult methodology for diagnosis. Stable-isotope breath tests hold great potential for rapidly diagnosing an infectious disease, monitoring therapy, and determining a bacterial phenotype in a rapid, point-of-care manner that does not require invasive sampling. Here we describe the preclinical development of a potentially highly selective TB diagnostic breath test based upon the organism’s CO dehydrogenase activity. After development of the testin vitro, we were able to use the breath test to discriminate between infected and control rabbits, demonstrating that a diagnosis can potentially be made and also that a complex bacterial phenotype can be noninvasively and rapidly studied in the host.IMPORTANCETuberculosis (TB) remains a major infectious cause of disease and death worldwide, and effective diagnosis and then treatment are the tools with which we fight TB. The more quickly and more specific the diagnosis can be made, the better, and this is also true of diagnosis being as close to the patient (point of care) as possible. Here we report our preclinical development of breath tests based upon specific mycobacterial metabolism that could, with development, allow rapid point-of-care diagnosis through measuring the mycobacterial conversion of labeled CO to labeled CO2.

Preparation and In Vitro Evaluation of Electrochemically-Aligned Collagen Matrix as a Dermal Substitute

MRS Advances ◽  
2016 ◽  
Vol 1 (18) ◽  
pp. 1295-1300 ◽  
Author(s):  
XingGuo Cheng ◽  
Nicole Edwards ◽  
Kelly Leung ◽  
David Zhang ◽  
Robert J. Christy
Keyword(s):  
Transmission Rate ◽  
Collagen Matrix ◽  
Electrochemical Process ◽  
Dermal Substitute ◽  
Adipose Derived Stem Cells ◽  
The Matrix ◽  
Moisture Vapor ◽  
Near Future

ABSTRACTDue to injuries and disease, there is a great need for a robust, biocompatible, biodegradable, skin-like dermal substitute to repair and regenerate damaged or lost skin. A novel electrochemical process was used to fabricate planarly aligned, densely packed collagen-based sheet which closely mimics the major structure of collagen in skin. The collagen matrix was characterized by scanning electron microscopy (SEM), oxygen permeation, moisture vapor transmission rate (MVTR), and mechanical strength. The seeding and proliferation of adipose derived stem cells (ADSCs) on the matrix was also evaluated. The results indicate that electrochemically-aligned collagen matrix has good MVTR, superior oxygen permeability, and is robust and biocompatible. Thus, it will be evaluated in vivo in the near future as a dermal substitute material.

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