scholarly journals Novel SH-SAW Biosensors for Ultra-Fast Recognition of Growth Factors

Biosensors ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 17
Author(s):  
Daniel Matatagui ◽  
Ágatha Bastida ◽  
M. Carmen Horrillo
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Test Time ◽  
Dynamic Mode ◽  
Label Free ◽  
Fast Recognition ◽  
Short Period ◽  
Wide Range ◽  
Total Test Time ◽  
Total Test

In this study, we investigated a label-free time efficient biosensor to recognize growth factors (GF) in real time, which are of gran interesting in the regulation of cell division and tissue proliferation. The sensor is based on a system of shear horizontal surface acoustic wave (SH-SAW) immunosensor combined with a microfluidic chip, which detects GF samples in a dynamic mode. In order to prove this method, to our knowledge not previously used for this type of compounds, two different GFs were tested by two immunoreactions: neurotrophin-3 and fibroblast growth factor-2 using its polyclonal antibodies. GF detection was conducted via an enhanced sequential workflow to improve total test time of the immunoassay, which shows that this type of biosensor is a very promising method for ultra-fast recognition of these biomolecules due to its great advantages: portability, simplicity of use, reusability, low cost, and detection within a relatively short period of time. Finally, the biosensor is able to detect FGF-2 growth factor in a concentration wide range, from 1–25 µg/mL, for a total test time of ~15 min with a LOD of 130 ng/mL.

Repeated Measures Battery for the Aged

1987 ◽  
Vol 31 (8) ◽  
pp. 852-856
Author(s):  
Richard H. Shannon
Keyword(s):  
Repeated Measures ◽  
Age Groups ◽  
Test Time ◽  
Control Group ◽  
Men And Women ◽  
Males And Females ◽  
Basic Ability ◽  
Older Males ◽  
Total Test Time ◽  
Total Test

A battery of 29 reliable, valid and repeatable cognitive and psychomotor paper-and-pencil tests, with each test measuring a specific construct, was used to assess the performance of 48 older males and females. These subjects were divided into three separate age groups: 55–60, 65–70, and 75–80 years. In addition, a group of 16 men and women aged 25–35 served as a control group. This battery is divided into three sub-batteries (A, B and C) which were given on three separate weeks. The emphasis of this paper will be to describe the results of the nine tests contained in sub-battery C. Each test of a basic ability was analyzed separately across a total of five days and fifteen trials, with three trials being given each day. Total test time for each trial was approximately 35 minutes.

scholarly journals Fluid elements—a concept for automation of diagnostic tests

1997 ◽  
Vol 43 (2) ◽  
pp. 369-378 ◽  
Author(s):  
Henk Van Damme ◽  
Thea Van Velthoven ◽  
Erik Kaelen ◽  
Eduard Pelssers
Keyword(s):  
Detection Limit ◽  
Hepatitis B ◽  
Diagnostic Tests ◽  
State Of The Art ◽  
Hepatitis B Surface Antigen ◽  
Test Time ◽  
Liquid Handling ◽  
Set Up ◽  
Total Test Time ◽  
Total Test

Abstract Constructs consisting of a channel, a membrane, and an absorber are designed for autonomously carrying out various liquid-handling functions of analytical tests. These so-called fluid elements can be used to set up various circuits for conducting several kinds of analytical tests. To demonstrate the feasibility of this concept, we constructed such a circuit and used it to perform, with two handling steps, an ELISA of hepatitis B surface antigen. The detection limit of the assay was comparable with those of state-of-the-art ELISAs for screening blood, and results could be obtained within a total test time of 20 min. We anticipate that this concept of automation may also serve as a basis for new, highly simplified immunoanalyzers.

Aptamers targeting vascular endothelial growth factor molecular regulation as potential therapists

2021 ◽  
Author(s):  
Moataz Dowaidar
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Molecular Regulation ◽  
Dna Aptamers ◽  
Vascular Endothelial ◽  
Vegf Signaling ◽  
Anti Vegf ◽  
Short Period ◽  
Wide Range ◽  
Endothelial Growth Factor

The discovery of vascular endothelial growth factor (VEGF) and its vital biological function has changed our knowledge of vasculogenesis and angiogenesis, while introducing a new strategy to the anticancer arsenal: this protein's specialized inhibition. Discovering VEGF's molecular regulation as well as developing revolutionary therapeutic strategies that directly or indirectly target VEGF is an outstanding case study that demonstrates the relevance of basic research in directing innovation and translational medicine. Following FDA approval of pegaptanib for AMD therapy, nucleic acid-based aptamers were discovered and developed. In an efficient bench-to-bedside process, a spate of new aptamers targeting a range of targets were discovered in a short period as high-potential therapists. Anti-VEGF DNA-based aptamers were the most significant. Standard SELEX processes were utilized to find most anti-VEGF DNA aptamers, while some of them employed alternate and upgraded SELEX-based techniques. After identifying the best oligonucleotide sequences, the highest affinity aptamers were further refined for target binding and/or activity. Synthesizing and evaluating the parent aptamer's structural analogs was utilized to find strategies to boost performance. Despite aptasensor success in a wide range of signal transduction approaches, which also allow extremely low detection limits, more work has to be done to construct meaningful and easy-to-use VEGF aptasensors for point-of-care diagnostics. In actuality, most published Aptasensors have only been evaluated in vitro, and it is vital to broaden their use to future in vivo situations and difficult clinical data. Creating high-affinity anti-VEGF DNA aptamers paves the path for additional diagnostic and therapeutic application research. Given the biological complexity of VEGF signaling, pharmacological combination therapies can significantly improve conventional anticancer treatments. These can be combined with VEGF signaling suppression to give more effective therapy and avoid resistance, which is frequent in cancer.

Extracellular matrix in obesity – cancer interactions

2015 ◽  
Vol 22 (2) ◽  
Author(s):  
Stephany C. Barreto ◽  
Christina A. Hopkins ◽  
Meghnad Bhowmick ◽  
Amitabha Ray
Keyword(s):  
Extracellular Matrix ◽  
Growth Factors ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Matricellular Proteins ◽  
Wide Range ◽  
Range Of Functions ◽  
Almost All ◽  
Chemical Mediators

AbstractObesity or overweight is a risk factor for several health disorders such as type 2 diabetes, hypertension, and certain cancers. Furthermore, obesity affects almost all body systems including the extracellular matrix (ECM) by generating a pro-inflammatory environment, which are associated with abnormal secretions of several cytokines or hormonal substances, for example, insulin-like growth factors (IGFs), leptin, and sex hormones. These chemical mediators most likely have a great impact on the ECM. Accumulating evidence suggests that both obesity and ECM can influence tumor growth and progression through a number of chemical mediators. Conversely, cells in the connective tissue, namely fibroblasts and macrophages, support and aggravate the inflammatory situation in obesity by releasing several cytokines or growth factors such as vascular endothelial growth factor, epidermal growth factor, and transforming growth factor-beta (TGF-β). A wide range of functions are performed by TGF-β in normal health and pathological conditions including tumorigenesis. Breast cancer in postmenopausal women is a classic example of obesity-related cancer wherein several of these conditions, for example, higher levels of pro-inflammatory cytokines, impairment in the regulation of estrogen and growth factors, and dysregulation of different ECM components may favor the neoplastic process. Aberrant expressions of ECM components such as matrix metalloproteinases or matricellular proteins in both obesity and cancer have been reported by many studies. Nonstructural matricellular proteins, viz., thrombospondins, secreted protein acidic and rich in cysteine (SPARC), and Cyr61-CTGF-Nov (CCN), which function as modulators of cell-ECM interactions, exhibit protean behavior in cancer. Precise understanding of ECM biology can provide potential therapeutic targets to combat obesity-related pathologies.

scholarly journals DETERMINATION OF GLYCOGEN IN BEE ORGAN TISSUES AS AN ENERGY METABOLISM PARAMETER

2018 ◽  
pp. 61-63
Author(s):  
I. V. Serduchenko ◽  
N. N. Gugushvili
Keyword(s):  
Cost Effectiveness ◽  
Energy Metabolism ◽  
Colorimetric Method ◽  
Weather Conditions ◽  
Test Time ◽  
Glycogen Level ◽  
Unfavorable Weather ◽  
Total Test Time ◽  
Total Test

New method of glycogen determination in bee organ tissues, considerably different from the existing ones, was suggested. Ghoreishi’s colorimetric method used today is time-, labor- and cost-consuming as the major reagent – orcin – is quite expensive. Comparison of cost-effectiveness of the two methods demonstrated that the proposed technique makes it possible to reduce expenses by using a more available and less expensive resorcin instead of orcin and reducing total test time from 4 to 3 hours 5 minutes. Glycogen contents determination using the updated method was performed in bees of four breeds: Italian-Carpathian, Carpathian, Oka, gray Caucasus mountain honeybees. It was determined that the Oka honeybees demonstrated the highest glycogen level. It is known that the higher is glycogen contents in organs and tissues the better is energy metabolism in insects. Consequently, honeybees of Oka breeds have higher resistance to unfavorable weather conditions and can produce progeny with a higher level of immunity. So, the specified method of glycogen determination in bee organ tissues increases the accuracy of diagnosis and plays a very important role in determining the level of energy metabolism in insects and will be useful for apiculture.

Magnetic orientation of four-ball test specimens and the effect on total test time

Nature ◽  
1978 ◽  
Vol 274 (5670) ◽  
pp. 459-460 ◽  
Author(s):  
J. B. JONES ◽  
G. POCOCK
Keyword(s):  
Test Time ◽  
Magnetic Orientation ◽  
Ball Test ◽  
Total Test Time ◽  
Total Test

scholarly journals Mobile Computing Technologies for Health and Mobility Assessment: Research Design and Results of the Timed Up and Go Test in Older Adults

Sensors ◽  
2020 ◽  
Vol 20 (12) ◽  
pp. 3481 ◽  
Author(s):  
Vasco Ponciano ◽  
Ivan Miguel Pires ◽  
Fernando Reinaldo Ribeiro ◽  
María Vanessa Villasana ◽  
Rute Crisóstomo ◽  
...  
Keyword(s):  
Mobile Devices ◽  
Pressure Sensor ◽  
Return Time ◽  
Emerging Diseases ◽  
Test Time ◽  
Time Duration ◽  
Accelerometer Sensor ◽  
Timed Up And Go ◽  
Total Test Time ◽  
Total Test

Due to the increasing age of the European population, there is a growing interest in performing research that will aid in the timely and unobtrusive detection of emerging diseases. For such tasks, mobile devices have several sensors, facilitating the acquisition of diverse data. This study focuses on the analysis of the data collected from the mobile devices sensors and a pressure sensor connected to a Bitalino device for the measurement of the Timed-Up and Go test. The data acquisition was performed within different environments from multiple individuals with distinct types of diseases. Then this data was analyzed to estimate the various parameters of the Timed-Up and Go test. Firstly, the pressure sensor is used to extract the reaction and total test time. Secondly, the magnetometer sensors are used to identify the total test time and different parameters related to turning around. Finally, the accelerometer sensor is used to extract the reaction time, total test time, duration of turning around, going time, return time, and many other derived metrics. Our experiments showed that these parameters could be automatically and reliably detected with a mobile device. Moreover, we identified that the time to perform the Timed-Up and Go test increases with age and the presence of diseases related to locomotion.

scholarly journals A lateral flow strip based on gold nanoparticles to detect 6-monoacetylmorphine in oral fluid

2018 ◽  
Vol 5 (6) ◽  
pp. 180288 ◽  
Author(s):  
Jia Liu ◽  
Xiaolong Hu ◽  
Fangqi Cao ◽  
Yurong Zhang ◽  
Jianzhong Lu ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Oral Fluid ◽  
Colour Change ◽  
Cross Reactivity ◽  
Lateral Flow ◽  
Driving Under The Influence ◽  
Test Time ◽  
Lateral Flow Strip ◽  
Total Test Time ◽  
Total Test

We used lateral flow strips based on gold nanoparticles to detect 6-monoacetylmorphine (6-MAM; heroin's unique metabolite) in oral fluid samples. In this competitive lateral chromatographic immunoassay, the 6-MAM was chemically synthesized and conjugated to bovine serum albumin. The results were qualitatively detected via the colour change of the test line. By using a proper sample pad, a suitable nitrocellulose membrane and a customized sponge device adsorbed the oral fluid directly from the mouth; the total test time was 3 min. The sensitivity of the assay was 4.0 ng ml −1 without any cross-reactivity with 10 normal drugs, which are widely subject to abuse, including morphine and codeine. This test could be easily used on site to detect heroin in oral fluid, and it could be a promising product in the future including for driving under the influence.

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