Present work demonstrates the fabrication of new and facile sandwich‐type electrochemical immunosensor based on palladium nanoparticles (PdNPs), polyaniline (PANI) and fullerene‐C60 nanocomposite ...film modified glassy carbon electrode (PdNP@PANI‐C60/GCE) for ultrasensitive detection of Prostate‐specific antigen (PSA) biomarker. PdNP@PANI‐C60 was electrochemically synthesized on GCE and used as an electroactive substrate. PdNP@PANI‐C60 was characterized by scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDS), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Primary antibody anti‐PSA (Ab1) was covalently immobilized on PdNP@PANI‐C60/GCE using NHS/EDC linkers. In the presence of PSA antigen, horseradish peroxidase secondary antibody (HRP‐Ab2) was brought into the surface of the electrode, developing stable amplified signals of H2O2 reduction. Under the optimal conditions, a linear curve for determination of PSA at the proposed immunosensor was 1.6×10−4 ng.mL−1 to 38 ng.mL−1 with a limit of detection (LOD) of 1.95×10−5 ng.mL−1. The proposed immunosensor was successfully validated in serum and urine samples towards PSA detection with satisfactory and acceptable results.
Tea consumption and disease correlations Sanlier, Nevin; Gokcen, Buşra Basar; Altuğ, Mehmet
Trends in food science & technology,
08/2018, Letnik:
78
Journal Article
Recenzirano
Tea is the most widely consumed beverage in the world next to water and is obtained from the leaves Camellia sinensis. In recent years, the potential health benefits and effect mechanisms of tea have ...attracted a lot of interest. The potential health benefits of tea have been attributed to its various phenolic compounds with unique biological properties found in tea. These phenolic compounds are especially catechins and their derivatives, which constitute at most 30% of the dry weight of the tea. Tea is a new and effective strategy for reducing the severity of neurological diseases and for protecting against obesity, cardiovascular disease, type 2 diabetes and certain types of cancer (ovaryum, lung, skin, breast, endometrial, prostate, bladder, oral and colorectal cancers).
Overall, the study that supports the health benefits of tea is increasing. But, the amounts of and the frequency of tea consumption that is associated with potential health benefits vary greatly from work to work and this situation creates difficulty in determining the optimal consumption amount and frequency that tea can exhibit health benefits. For this reason, we aimed to examine the health effect of the tea and how much consumption is to investigate whether it meets the claimed health benefits.
Within that frame, there is a need for more studies on the possible health effects of tea. While studying on that effect, the effects of various doses, forms (in synthetic or natural product matrix), exposure in different periods (short or long term) on health should be studied. However, currently the conducted studies are promising for tea is a bioactive component like polyphenol, theaflavins, thearubigins, caffeine and mineral. In addition, although the fact intake with diet proved to be reliable at the end of the conducted acute and chronic toxicity test is another positive part, safety of bioactive component in tea should be supported through further studies.
•Tea is classified in four main groups as black tea, green tea, white tea and oolong tea depend on the fermentation process of tea.•The potential health benefits and effect mechanisms of tea have attracted a lot of interest.•Important phenolic compounds found in tea are catechins and their derivatives.•Tea has beneficial effects on many chronic diseases.
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•Three-dimensional (3D) ZnIn2S4 (ZIS) was firstly introduced in PEC immunoassay.•The Z-scheme 3D ZIS/WO3 photocatalyst showed outstanding photocatalytic activity and PEC ...performance.•The Z-scheme 3D ZIS/WO3 photocatalyst was firstly used to construct PEC immunosensor.•The immunosensor exhibited high selectivity and sensitivity for PSA detection.
A novel three-dimensional (3D) ZnIn2S4/WO3 (ZIS/WO3) photocatalyst is prepared via a simple hydrothermal method and used as photoanode material in constructing photoelectrochemical (PEC) immunosensor of prostate specific antigen (PSA). The photocatalyst presents high activity, and its photocurrent intensity is up to 23 and 7 times of WO3 and ZnIn2S4 (ZIS) respectively, under 430 nm light illumination. The improved PEC behavior is due to the sensitization and 3D structure of ZIS and the formation of Z-scheme heterojunction between ZIS and WO3, which greatly enhance light harvesting, promote the spatial separation of interfacial charges and prolong the lifetime of photogenerated electrons. At the same time, the high oxidation capacity of valence band holes of WO3 is retained. A label-free PEC immunosensor is fabricated by using the photocatalyst, and it shows good performance for PSA detection. The linear response range is 0.01–500 ng/mL, and the detection limit is low to 5 pg/mL. Moreover, the PEC immunosensor afforded high stability, specificity and reproducibility. Therefore, it possesses great application potential in biological/clinical analysis.
Androgen-receptor splice variant 7 (AR-V7) is associated with castration-resistant prostate cancer (CRPC) and resistance to anti-androgen therapy. Despite its clinical importance, the lack of ...efficient methods for AR-V7 analysis remains a challenge for broader use of this biomarker in routine clinical practice. Herein, we suggest a practical and non-invasive liquid biopsy method for analysis of AR-V7 in the RNA of urine-derived extracellular vesicles (EVs) without the need for blood withdrawal. Urine-derived EVs were isolated by a lab-on-a-disc integrated with six independent nanofiltration units (Exo-Hexa) allowing simultaneous processing of six individual samples. Rapid enrichment of EVs (<30 min) from each 4 mL urine sample was followed by mRNA extraction, and AR-V7 and androgen receptor full-length (AR-FL) mRNA levels in the urinary EVs were quantified by droplet digital polymerase chain reaction (ddPCR) as absolute concentrations (copies per mL). Higher AR-V7 and lower AR-FL expressions were detected in urine-derived EVs from 14 patients with CRPC than in those from 22 patients with hormone-sensitive prostate cancer. Additionally, we found that AR-V7 transcript levels and the AR-V7/AR-FL ratio in urinary EVs were higher in patients with advanced prostate cancer. This study is the first to report that RNA of urine-derived EVs is a reliable source for AR-V7 expression analysis. The proposed method for quantifying AR-V7 in urinary EVs prepared by a lab-on-a-disc is therefore a simple and promising approach to liquid biopsy with great potential for therapeutic impact on prostate cancer.
Objectives
The aim of this study was to systematically review the literature and perform a meta-analysis of machine learning (ML) diagnostic accuracy studies focused on clinically significant ...prostate cancer (csPCa) identification on MRI.
Methods
Multiple medical databases were systematically searched for studies on ML applications in csPCa identification up to July 31, 2019. Two reviewers screened all papers independently for eligibility. The area under the receiver operating characteristic curves (AUC) was pooled to quantify predictive accuracy. A random-effects model estimated overall effect size while statistical heterogeneity was assessed with the
I
2
value. A funnel plot was used to investigate publication bias. Subgroup analyses were performed based on reference standard (biopsy or radical prostatectomy) and ML type (deep and non-deep).
Results
After the final revision, 12 studies were included in the analysis. Statistical heterogeneity was high both in overall and in subgroup analyses. The overall pooled AUC for ML in csPCa identification was 0.86, with 0.81–0.91 95% confidence intervals (95%CI). The biopsy subgroup (
n
= 9) had a pooled AUC of 0.85 (95%CI = 0.79–0.91) while the radical prostatectomy one (
n
= 3) of 0.88 (95%CI = 0.76–0.99). Deep learning ML (
n
= 4) had a 0.78 AUC (95%CI = 0.69–0.86) while the remaining 8 had AUC = 0.90 (95%CI = 0.85–0.94).
Conclusions
ML pipelines using prostate MRI to identify csPCa showed good accuracy and should be further investigated, possibly with better standardisation in design and reporting of results.
Key Points
• Overall pooled AUC was 0.86 with 0.81–0.91 95% confidence intervals.
• In the reference standard subgroup analysis, algorithm accuracy was similar with pooled AUCs of 0.85 (0.79–0.91 95% confidence intervals) and 0.88 (0.76–0.99 95% confidence intervals) for studies employing biopsies and radical prostatectomy, respectively.
• Deep learning pipelines performed worse (AUC = 0.78, 0.69–0.86 95% confidence intervals) than other approaches (AUC = 0.90, 0.85–0.94 95% confidence intervals).
Circulating tumor cells (CTCs) offer tremendous potential for the detection and characterization of cancer. A key challenge for their isolation and subsequent analysis is the extreme rarity of these ...cells in circulation. Here, a novel label‐free method is described to enrich viable CTCs directly from whole blood based on their distinct deformability relative to hematological cells. This mechanism leverages the deformation of single cells through tapered micrometer scale constrictions using oscillatory flow in order to generate a ratcheting effect that produces distinct flow paths for CTCs, leukocytes, and erythrocytes. A label‐free separation of circulating tumor cells from whole blood is demonstrated, where target cells can be separated from background cells based on deformability despite their nearly identical size. In doping experiments, this microfluidic device is able to capture >90% of cancer cells from unprocessed whole blood to achieve 104‐fold enrichment of target cells relative to leukocytes. In patients with metastatic castration‐resistant prostate cancer, where CTCs are not significantly larger than leukocytes, CTCs can be captured based on deformability at 25× greater yield than with the conventional CellSearch system. Finally, the CTCs separated using this approach are collected in suspension and are available for downstream molecular characterization.
Deformability‐based separation of circulating tumor cells (CTCs) from similarly sized leukocytes using microfluidic ratchets formed by oscillatory flow through asymmetrical constrictions is demonstrated. This mechanism can process whole blood directly to provide divergent paths for CTCs, leukocytes, and erythrocytes depending on cell deformability. In concurrent tests against conventional methods, this system is able to isolate ≈25× more CTCs from patients with castrate resistant prostate cancer.
Fatty acid (FA) profiling provides phenotypic information and is increasingly used in a broad range of biological and biomedical studies. Quantitation of unsaturated FAs with confident carbon–carbon ...double bond (CC) location assignment is both sample and time consuming using traditional gas chromatography mass spectrometry analysis. In this study, we developed a rapid, sensitive, and quantitative method for profiling unsaturated FAs without using chromatographic separations. This method was based on a combination of in-solution photochemical tagging of a CC in FAs and a subsequent gas-phase detagging via tandem (neutral loss scan) mass spectrometry. It enabled quantitation of unsaturated FAs from various biological samples (blood, plasma, and cell lines). More importantly, quantitative information on FA CC location isomers, which was traditionally overlooked, could now be obtained and applied to studying FA changes between normal and cancerous human prostate cells.
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•A novel sandwich-type electrochemical immunosensor was designed for the detection of PSA.•Loading of primary antibody increased using AuNPs/CHI/SPE sensing platform.•The fabricated ...immunosensor demonstrated excellent sensitivity, special selectivity and long-term stability.•The immunosensor was validated to detect PSA in real samples.•The immunosensor displayed a promising capability in clinical applications.
In this study, we have developed an electrochemical immunosensor for the detection of prostate-specific antigen (PSA) based on gold nanoparticles (AuNPs) and a chitosan (CHI) nanocomposite film coated on a screen printed electrode (SPE). The modified SPE was characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The immunosensor was fabricated by sequential immobilization of anti-PSA primary antibody, PSA antigen and HRP-tagged secondary antibody on the surface of AuNPs/CHI/SPE. When this immunosensor was placed in 2.5mM H2O2, as HRP substrate, and 1mM methylene blue (MB), as redox mediator, greatly amplified immunosensing signals were observed. Immunosensing signals for the reduction of H2O2 were monitored in phosphate buffer (pH 7.0) by CV and square wave voltammetry (SWV). Under optimized conditions steady state current increased linearly with PSA concentration over the range 1–18ng/ml with a detection limit of 0.001ng/ml. The fabricated immunosensor demonstrated excellent sensitivity, stability and reproducibility and therefore was successfully applied to analyse PSA in biological samples. Finally, the results indicate that the proposed immunosensor has potential in clinical screening of cancer biomarkers.
Cadmium (Cd) is a heavy metal belonging to the group of the main chemical pollutants of the natural and occupational environment in economically developed countries. The forecasts indicate that ...contamination of the environment with this toxic metal, and thus the exposure of the general population, will increase. Food (particularly plant products) is the main source of the general population exposure to this element. Moreover, an important, and often the main, source of intoxication with Cd is habitual tobacco smoking. Recent epidemiological studies have provided numerous evidence that even low-level environmental exposure to this toxic metal, nowadays occurring in numerous economically developed countries, creates a risk for health of the general population. The low-level lifetime exposure to this metal may lead to the damage to the kidneys, liver, skeletal system, and cardiovascular system, as well as to the deterioration of the sight and hearing. Moreover, it has been suggested that environmental exposure to this xenobiotic may contribute to the development of cancer of the lung, breast, prostate, pancreas, urinary bladder, and nasopharynx. Taking the above into account, the aim of this review article is to draw more attention to Cd as an environmental risk factor for the health of the general population and the need to undertake preventive actions allowing to reduce the risk of health damage due to a lifetime exposure to this toxic metal.
We present the very first worldwide ever-reported electrochemical biosensor based on a memristive effect and DNA aptamers. This novel device is developed to propose a completely new approach in ...cancer diagnostics. In this study, an affinity-based technique is presented for the detection of the prostate specific antigen (PSA) using DNA aptamers. The hysteretic properties of memristive silicon nanowires functionalized with these DNA aptamers provide a label-free and ultrasensitive biodetection technique. The ultrasensitive detection is hereby demonstrated for PSA with a limit of detection down to 23 aM, best ever published value for electrochemical biosensors in PSA detection. The effect of polyelectrolytes on our memristive devices is also reported to further show how positive or negative charges affect the memristive hysteresis. With such an approach, combining memristive nanowires and aptamers, memristive aptamer-based biosensors can be proposed to detect a wide range of cancer markers with unprecedent ultrasensitivities to also address the issue of an early detection of cancer.
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