scholarly journals Recent Advances in Electrochemical and Optical Sensing of Dopamine

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1039 ◽  
Author(s):  
Faten Bashar Kamal Eddin ◽  
Yap Wing Fen
Keyword(s):  
Neurological Disorders ◽  
Treatment Cost ◽  
Biological Fluids ◽  
Biological Species ◽  
Advanced Materials ◽  
Sensor Surface ◽  
Materials Used

Nowadays, several neurological disorders and neurocrine tumours are associated with dopamine (DA) concentrations in various biological fluids. Highly accurate and ultrasensitive detection of DA levels in different biological samples in real-time can change and improve the quality of a patient’s life in addition to reducing the treatment cost. Therefore, the design and development of diagnostic tool for in vivo and in vitro monitoring of DA is of considerable clinical and pharmacological importance. In recent decades, a large number of techniques have been established for DA detection, including chromatography coupled to mass spectrometry, spectroscopic approaches, and electrochemical (EC) methods. These methods are effective, but most of them still have some drawbacks such as consuming time, effort, and money. Added to that, sometimes they need complex procedures to obtain good sensitivity and suffer from low selectivity due to interference from other biological species such as uric acid (UA) and ascorbic acid (AA). Advanced materials can offer remarkable opportunities to overcome drawbacks in conventional DA sensors. This review aims to explain challenges related to DA detection using different techniques, and to summarize and highlight recent advancements in materials used and approaches applied for several sensor surface modification for the monitoring of DA. Also, it focuses on the analytical features of the EC and optical-based sensing techniques available.

scholarly journals CRISPR Gene-Editing Models Geared Toward Therapy for Hereditary and Developmental Neurological Disorders

2021 ◽  
Vol 9 ◽  
Author(s):  
Poh Kuan Wong ◽  
Fook Choe Cheah ◽  
Saiful Effendi Syafruddin ◽  
M. Aiman Mohtar ◽  
Norazrina Azmi ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Neurological Disorders ◽  
Gene Editing ◽  
Fragile X ◽  
Genetic Diseases ◽  
Basic Principles ◽  
Short Palindromic Repeat

Hereditary or developmental neurological disorders (HNDs or DNDs) affect the quality of life and contribute to the high mortality rates among neonates. Most HNDs are incurable, and the search for new and effective treatments is hampered by challenges peculiar to the human brain, which is guarded by the near-impervious blood-brain barrier. Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR), a gene-editing tool repurposed from bacterial defense systems against viruses, has been touted by some as a panacea for genetic diseases. CRISPR has expedited the research into HNDs, enabling the generation of in vitro and in vivo models to simulate the changes in human physiology caused by genetic variation. In this review, we describe the basic principles and workings of CRISPR and the modifications that have been made to broaden its applications. Then, we review important CRISPR-based studies that have opened new doors to the treatment of HNDs such as fragile X syndrome and Down syndrome. We also discuss how CRISPR can be used to generate research models to examine the effects of genetic variation and caffeine therapy on the developing brain. Several drawbacks of CRISPR may preclude its use at the clinics, particularly the vulnerability of neuronal cells to the adverse effect of gene editing, and the inefficiency of CRISPR delivery into the brain. In concluding the review, we offer some suggestions for enhancing the gene-editing efficacy of CRISPR and how it may be morphed into safe and effective therapy for HNDs and other brain disorders.

Experimental Evaluation of Biocompatibility in Case of Acrylic Materials by Bio-Testing on Lab Animals

2016 ◽  
Vol 695 ◽  
pp. 231-235
Author(s):  
Mihaela Păpușa Vasiliu ◽  
Liliana Sachelarie ◽  
Daniela Ivona Tomita ◽  
Elena Folescu ◽  
Carmen Stadoleanu
Keyword(s):  
Biological Fluids ◽  
Dental Materials ◽  
Living Organism ◽  
Council Directive ◽  
Materials Used ◽  
Physical Degradation ◽  
Bio Compatibility ◽  
And Storage

A bio material is a inert and non-viable material with a natural or synthetic origin that comes in to contact with tissues, blood or biological fluids, being used in prosthetic, therapeutic and storage applications, without affecting in any way living organism or their components.Biological systems may produce the deterioration of materials, process known as bio-degradation. In case of oral environment this also includes the dissolution in saliva, chemical and physical degradation, abrasion and erosion caused by the diet components, mastication process and bacteria actions. Most of the materials used in dental therapy may be toxic or may produce allergies until they bind.We evaluated during our experiment the biological consequences (bio-compatibility) that subcutaneous implanting of small acrylic dental fragments have upon tissues in case of white lab mice, keeping an eye on the local tissues reactions. The evaluation of dental materials is made by testing the bio-compatibility. Biologically tests are performed in vivo and in vitro strictly in the lab and on animals.For our experiment we used 20 white mice Wistar line, 8-9 weeks old males, 40 grams, divided in 3 groups; all of them received an acrylic implant. The experiment was centered on the observation of some physiological or pathological effects, local or systemic, that implants may have produced effects that show a toxic answer or the rejection of the material.All experimens was performed in compliance with (European Communities Council Directive 1986 (86/609/EEC) and Ordinance No. 37 of Romanian Government from 2nd February 2002.Materials bio-compatibility was highlighted by anatomic-pathological exams during which we noticed all the modifications at dermis level during the entire period. We observed the phenomenon that occurred around the implants at different time periods, than we collected samples.The data obtained at the end of our experiment allow us to sustain that acrylic materials used in dental implants have all the properties required to be considered as bio-compatible.

Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

1995 ◽  
Vol 23 (1) ◽  
pp. 61-73
Author(s):  
Coenraad Hendriksen ◽  
Johan van der Gun
Keyword(s):  
Quality Control ◽  
Test Methods ◽  
In Vitro Test ◽  
Large Numbers ◽  
Alternative Approach ◽  
Inactivated Vaccines ◽  
Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

scholarly journals Tyrosol-Enriched Tomatoes by Diffusion across the Fruit Peel from a Chitosan Coating: A Proposal of Functional Food

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 335
Author(s):  
Silvia Tampucci ◽  
Antonella Castagna ◽  
Daniela Monti ◽  
Clementina Manera ◽  
Giuseppe Saccomanni ◽  
...  
Keyword(s):  
Tomato Fruit ◽  
Storage Period ◽  
Food Matrix ◽  
Fruit Peel ◽  
Fresh Food ◽  
In Vitro Permeation ◽  
Active Transfer

Chitosan is receiving increasing attention from the food industry for being a biodegradable, non-toxic, antimicrobial biopolymer able to extend the shelf life of, and preserve the quality of, fresh food. However, few studies have investigated the ability of chitosan-based coatings to allow the diffusion of bioactive compounds into the food matrix to improve its nutraceutical quality. This research is aimed at testing whether a hydrophilic molecule (tyrosol) could diffuse from the chitosan-tyrosol coating and cross the tomato peel. To this end, in vitro permeation tests using excised tomato peel and an in vivo application of chitosan-tyrosol coating on tomato fruit, followed by tyrosol quantification in intact fruit, peel and flesh during a seven-day storage at room temperature, were performed. Both approaches demonstrated the ability of tyrosol to permeate across the fruit peel. Along with a decreased tyrosol content in the peel, its concentration within the flesh was increased, indicating an active transfer of tyrosol into this tissue. This finding, together with the maintenance of constant tyrosol levels during the seven-day storage period, is very promising for the use of chitosan formulations to produce functional tomato fruit.

scholarly journals In vitro characteristics and in vivo platelet quality of whole blood treated with riboflavin and UVA / UVB light and stored for 24 hours at room temperature

Transfusion ◽  
2021 ◽  
Vol 61 (S1) ◽  
Author(s):  
Turid Helen Felli Lunde ◽  
Lindsay Hartson ◽  
Shawn Lawrence Bailey ◽  
Tor Audun Hervig
Keyword(s):  
Whole Blood ◽  
Room Temperature

scholarly journals Injectable non-leaching tissue-mimetic bottlebrush elastomers as an advanced platform for reconstructive surgery

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Erfan Dashtimoghadam ◽  
Farahnaz Fahimipour ◽  
Andrew N. Keith ◽  
Foad Vashahi ◽  
Pavel Popryadukhin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Reconstructive Surgery ◽  
Biomedical Applications ◽  
The Body ◽  
Surrounding Tissue ◽  
Curing Time ◽  
Materials Used ◽  
Significant Health

AbstractCurrent materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

scholarly journals Persistence of intramyocardially transplanted murine induced pluripotent stem cell-derived cardiomyocytes from different developmental stages

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gabriel Peinkofer ◽  
Martina Maass ◽  
Kurt Pfannkuche ◽  
Agapios Sachinidis ◽  
Stephan Baldus ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Stem Cell ◽  
Cell Adhesion ◽  
Developmental Stage ◽  
Pluripotent Stem Cell ◽  
Induced Pluripotent Stem Cell ◽  
Induced Pluripotent

Abstract Background Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) are regarded as promising cell type for cardiac cell replacement therapy, but it is not known whether the developmental stage influences their persistence and functional integration in the host tissue, which are crucial for a long-term therapeutic benefit. To investigate this, we first tested the cell adhesion capability of murine iPSC-CM in vitro at three different time points during the differentiation process and then examined cell persistence and quality of electrical integration in the infarcted myocardium in vivo. Methods To test cell adhesion capabilities in vitro, iPSC-CM were seeded on fibronectin-coated cell culture dishes and decellularized ventricular extracellular matrix (ECM) scaffolds. After fixed periods of time, stably attached cells were quantified. For in vivo experiments, murine iPSC-CM expressing enhanced green fluorescent protein was injected into infarcted hearts of adult mice. After 6–7 days, viable ventricular tissue slices were prepared to enable action potential (AP) recordings in transplanted iPSC-CM and surrounding host cardiomyocytes. Afterwards, slices were lysed, and genomic DNA was prepared, which was then used for quantitative real-time PCR to evaluate grafted iPSC-CM count. Results The in vitro results indicated differences in cell adhesion capabilities between day 14, day 16, and day 18 iPSC-CM with day 14 iPSC-CM showing the largest number of attached cells on ECM scaffolds. After intramyocardial injection, day 14 iPSC-CM showed a significant higher cell count compared to day 16 iPSC-CM. AP measurements revealed no significant difference in the quality of electrical integration and only minor differences in AP properties between d14 and d16 iPSC-CM. Conclusion The results of the present study demonstrate that the developmental stage at the time of transplantation is crucial for the persistence of transplanted iPSC-CM. iPSC-CM at day 14 of differentiation showed the highest persistence after transplantation in vivo, which may be explained by a higher capability to adhere to the extracellular matrix.

scholarly journals Pharmacological Effects and Potential Clinical Usefulness of Polyphenols in Benign Prostatic Hyperplasia

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 450
Author(s):  
Kensuke Mitsunari ◽  
Yasuyoshi Miyata ◽  
Tomohiro Matsuo ◽  
Yuta Mukae ◽  
Asato Otsubo ◽  
...  
Keyword(s):  
Benign Prostatic Hyperplasia ◽  
Molecular Mechanisms ◽  
Prostatic Hyperplasia ◽  
Pathological Conditions ◽  
Urinary Tract Symptoms ◽  
Anti Inflammatory ◽  
Lower Urinary

Benign prostatic hyperplasia (BPH) is arguably the most common benign disease among men. This disease is often associated with lower urinary tract symptoms (LUTS) in men and significantly decreases the quality of life. Polyphenol consumption reportedly plays an important role in the prevention of many diseases, including BPH. In recent years, in addition to disease prevention, many studies have reported the efficacy and safety of polyphenol treatment against various pathological conditions in vivo and in vitro. Furthermore, numerous studies have also revealed the molecular mechanisms of the antioxidant and anti-inflammatory effects of polyphenols. We believe that an improved understanding of the detailed pharmacological roles of polyphenol-induced activities at a molecular level is important for the prevention and treatment of BPH. Polyphenols are composed of many members, and their biological roles differ. In this review, we first provide information regarding the pathological roles of oxidative stress and inflammation in BPH. Next, the antioxidant and anti-inflammatory effects of polyphenols, including those of flavonoids and non-flavonoids, are discussed. Finally, we talk about the results and limitations of previous clinical trials that have used polyphenols in BPH, with particular focus on their molecular mechanisms of action.

The Role of microRNAs in Osteoporosis Diagnostics

2021 ◽  
Vol 30 (03) ◽  
pp. 222-229
Author(s):  
Matthias Hackl ◽  
Elisabeth Semmelrock ◽  
Johannes Grillari
Keyword(s):  
Bone Mass ◽  
Bone Metabolism ◽  
Messenger Rna ◽  
Biological Fluids ◽  
Clinical Diagnostics ◽  
Bone Architecture ◽  
Estrogen Metabolism ◽  
Age Related

AbstractMicroRNAs (miRNAs) are short (18–24 nucleotides) non-coding RNA sequences that regulate gene expression via binding of messenger RNA. It is estimated that miRNAs co-regulate the expression of more than 70% of all human genes, many of which fulfil important roles in bone metabolism and muscle function. In-vitro and in-vivo experiments have shown that the targeted loss of miRNAs in distinct bone cell types (osteoblasts and osteoclasts) results in altered bone mass and bone architecture. These results emphasize the biological relevance of miRNAs for bone health.MiRNAs are not only considered as novel bone biomarkers because of their biological importance to bone metabolism, but also on the basis of other favorable properties: 1) Secretion of miRNAs from cells enables “minimally invasive” detection in biological fluids such as serum. 2) High stability of miRNAs in serum enables the retrospective analysis of frozen blood specimens. 3) Quantification of miRNAs in the serum is based on the RT-PCR - a robust method that is considered as the gold standard for the analysis of nucleic acids in clinical diagnostics.With regard to osteoporosis, it has been shown that many of the known risk factors are characterized by distinct miRNA profiles in the affected tissues: i) age-related loss of bone mass, ii) sarcopenia, iii) changes in estrogen metabolism and related changes Loss of bone mass, and iv) diabetes. Therefore, numerous studies in recent years have dealt with the characterization of miRNAs in the serum of osteoporosis patients and healthy controls, and were able to identify recurring miRNA patterns that are characteristic of osteoporosis. These novel biomarkers have great potential for the diagnosis and prognosis of osteoporosis and its clinical outcomes.The aim of this article is to give a summary of the current state of knowledge on the research and application of miRNA biomarkers in osteoporosis.

Folic Acid Functionalized Chlorin e6-Superparamagnetic Iron Oxide Nanocarriers as a Theranostic Agent for MRI-Guided Photodynamic Therapy

2021 ◽  
Vol 17 (2) ◽  
pp. 205-215
Author(s):  
Zhenbo Sun ◽  
Mingfang Luo ◽  
Jia Li ◽  
Ailing Wang ◽  
Xucheng Sun ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Folic Acid ◽  
Iron Oxide ◽  
Near Infrared ◽  
Biological Fluids ◽  
Superparamagnetic Iron Oxide ◽  
Chlorin E6 ◽  
Theranostic Agent

Imaging-guided cancer theranostic is a promising strategy for cancer diagnostic and therapeutic. Photodynamic therapy (PDT), as an approved treatment modality, is limited by the poor solubility and dispersion of photosensitizers (PS) in biological fluids. Herein, it is demonstrated that superparamagnetic iron oxide (SPIO)-based nanoparticles (SCFs), prepared by conjugated with Chlorin e6 (Ce6) and modified with folic acid (FA) on the surface, can be used as versatile drug delivery vehicles for effective PDT. The nanoparticles are great carriers for photosensitizer Ce6 with an extremely high loading efficiency. In vitro fluorescence imaging and in vivo magnetic resonance imaging (MRI) results indicated that SCFs selectively accumulated in tumor cells. Under near-infrared laser irradiation, SCFs were confirmed to be capable of inducing low cell viability of RM-1 cells In vitro and displaying efficient tumor ablation with negligible side effects in tumor-bearing mice models.

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