scholarly journals Analysis of Circulating MicroRNA: Preanalytical and Analytical Challenges

2011 ◽  
Vol 57 (6) ◽  
pp. 833-840 ◽  
Author(s):  
Jennifer S McDonald ◽  
Dragana Milosevic ◽  
Honey V Reddi ◽  
Stefan K Grebe ◽  
Alicia Algeciras-Schimnich
Keyword(s):  
Extraction Process ◽  
Circulating Microrna ◽  
Disease Biomarkers ◽  
Clinical Biomarkers ◽  
Individual Mirnas ◽  
Reverse Transcription Quantitative Pcr ◽  
Apparent Concentration ◽  
Total Variability ◽  
Cellular Components

BACKGROUND There is great interest in circulating microRNAs (miRNAs) as disease biomarkers. Translating promising miRNAs into validated clinical tests requires the characterization of many preanalytical and analytical parameters. METHODS miRNAs were extracted from serum and plasma samples of healthy volunteers, and miRNAs known to be present in serum and plasma (miR-15b, miR-16, miR-24, and miR-122) were amplified by reverse-transcription quantitative PCR. Stability and the effects of hemolysis were determined. Assay variation and its components, including the effect of adding control miRNA, were assessed by nested ANOVA. RESULTS miRNA concentrations were higher in plasma than in serum. Processing of plasma to remove subcellular/cellular components reduced miRNA concentrations to those of serum. The miRNAs analyzed were stable refrigerated or frozen for up to 72 h and were stable at room temperature for 24 h. Hemolysis increased the apparent concentration of 3 of the miRNAs. The total variability of replicate miRNA concentrations was <2.0-fold, with most of the variability attributable to the extraction process and interassay imprecision. Normalizing results to those of spiked exogenous control miRNAs did not improve this variability. CONCLUSIONS Detailed validation of the preanalytical steps affecting miRNA detection and quantification is critical when considering the use of individual miRNAs as clinical biomarkers. Unless these causes of imprecision are considered and mitigated, only miRNAs that are extremely up- or downregulated will be suitable as clinical biomarkers.

scholarly journals Very Fast and Accurate Procedure for the Characterization of Photovoltaic Panels from Datasheet Information

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Antonino Laudani ◽  
Francesco Riganti Fulginei ◽  
Alessandro Salvini ◽  
Gabriele Maria Lozito ◽  
Salvatore Coco
Keyword(s):  
Numerical Methods ◽  
Search Space ◽  
Extraction Process ◽  
Reduced Form ◽  
Photovoltaic Panels ◽  
Approximation Techniques ◽  
Computational Costs ◽  
Minimization Technique ◽  
Accurate Procedure

In recent years several numerical methods have been proposed to identify the five-parameter model of photovoltaic panels from manufacturer datasheets also by introducing simplification or approximation techniques. In this paper we present a fast and accurate procedure for obtaining the parameters of the five-parameter model by starting from its reduced form. The procedure allows characterizing, in few seconds, thousands of photovoltaic panels present on the standard databases. It introduces and takes advantage of further important mathematical considerations without any model simplifications or data approximations. In particular the five parameters are divided in two groups, independent and dependent parameters, in order to reduce the dimensions of the search space. The partitioning of the parameters provides a strong advantage in terms of convergence, computational costs, and execution time of the present approach. Validations on thousands of photovoltaic panels are presented that show how it is possible to make easy and efficient the extraction process of the five parameters, without taking care of choosing a specific solver algorithm but simply by using any deterministic optimization/minimization technique.

Optimization and characterization of flavonoids extracted from Cannabis sativa fibers

2021 ◽  
pp. 004051752110277
Author(s):  
Qilu Cui ◽  
Jiawei Li ◽  
Chongwen Yu
Keyword(s):  
Chemical Structure ◽  
Cannabis Sativa ◽  
Ethanol Concentration ◽  
Extraction Process ◽  
Test Results ◽  
Hemp Fiber ◽  
Hemp Fibers ◽  
Structure Surface ◽  
Degumming Process

In this paper, the extraction process of flavonoids from hemp fibers was studied. Response surface methodology (RSM) analysis of the extraction parameters indicated that optimized results would be ethanol concentration 76 vol.%, bath ratio 1:50, and reaction time 139 min; therefore, an optimal extraction rate of flavonoids of 0.2275% can be obtained. The chemical structure, surface morphology and element composition of flavonoid extracts were analyzed. The test results indicated that hemp extract contains flavonoids, which can be used to extract flavonoids from hemp fiber, so as to comprehensively develop hemp fiber and reduce the discharge of waste liquid in the traditional degumming process.

scholarly journals Enzymatic Extraction and Characterization of Pectin from Cocoa Pod Husks (Theobroma cacao L.) Using Celluclast® 1.5 L

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1473
Author(s):  
Licelander Hennessey-Ramos ◽  
Walter Murillo-Arango ◽  
Juliana Vasco-Correa ◽  
Isabel Cristina Paz Astudillo
Keyword(s):  
Acid Content ◽  
Galacturonic Acid ◽  
Extraction Process ◽  
Chemical Extraction ◽  
Enzymatic Extraction ◽  
Acid Yield ◽  
Physicochemical Features ◽  
Enzyme Dosage ◽  
Cocoa Pod Husks

Cocoa pod husks are a waste generated during the processing of cocoa beans. We aimed to explore the enzymatic extraction of pectin using cellulases. The extraction process was optimized using a central composite design (CCD) and analyzed by response surface methodology (RSM). The parameters optimized were feedstock concentration (%), enzyme dosage (µL/g), and time (h). Three dependent variables were studied: pectin yield (g/100 g dry husk) (R2 = 97.02), galacturonic acid content (g/100 g pectin) (R2 = 96.90), and galacturonic acid yield (g/100 g feedstock) (R2 = 95.35). The optimal parameters were 6.0% feedstock concentration, 40 µL g−1 of enzyme, and 18.54 h, conditions that produced experimentally a pectin yield of 10.20 g/100 g feedstock, 52.06 g galacturonic acid/100 g pectin, and a yield 5.31 g galacturonic acid/100 g feedstock. Using the chemical extraction method, a yield of 8.08 g pectin/100 g feedstock and a galacturonic acid content of 60.97 g/100 g pectin were obtained. Using assisted sonication, a pectin yield of 8.28 g/100 g feedstock and a galacturonic acid content of 42.77 g/100 g pectin were obtained. Enzymatically optimized pectin has rheological and physicochemical features typical of this biomaterial, which provides an interesting alternative for the valorization of cocoa husks.

scholarly journals Graphene, an Interesting Nanocarbon Allotrope for Biosensing Applications: Advances, Insights, and Prospects

2021 ◽  
Vol 12 ◽  
pp. 117959722098382
Author(s):  
Farid Menaa ◽  
Yazdian Fatemeh ◽  
Sandeep K Vashist ◽  
Haroon Iqbal ◽  
Olga N Sharts ◽  
...  
Keyword(s):  
Cost Effective ◽  
Genetic Alterations ◽  
Multiplex Detection ◽  
Quantitative Characterization ◽  
Disease Biomarkers ◽  
Qualitative And Quantitative ◽  
Sensing Systems ◽  
Doped Graphene ◽  
Bioanalytical Applications

Graphene, a relatively new two-dimensional (2D) nanomaterial, possesses unique structure (e.g. lighter, harder, and more flexible than steel) and tunable physicochemical (e.g. electronical, optical) properties with potentially wide eco-friendly and cost-effective usage in biosensing. Furthermore, graphene-related nanomaterials (e.g. graphene oxide, doped graphene, carbon nanotubes) have inculcated tremendous interest among scientists and industrials for the development of innovative biosensing platforms, such as arrays, sequencers and other nanooptical/biophotonic sensing systems (e.g. FET, FRET, CRET, GERS). Indeed, combinatorial functionalization approaches are constantly improving the overall properties of graphene, such as its sensitivity, stability, specificity, selectivity, and response for potential bioanalytical applications. These include real-time multiplex detection, tracking, qualitative, and quantitative characterization of molecules (i.e. analytes [H2O2, urea, nitrite, ATP or NADH]; ions [Hg2+, Pb2+, or Cu2+]; biomolecules (DNA, iRNA, peptides, proteins, vitamins or glucose; disease biomarkers such as genetic alterations in BRCA1, p53) and cells (cancer cells, stem cells, bacteria, or viruses). However, there is still a paucity of comparative reports that critically evaluate the relative toxicity of carbon nanoallotropes in humans. This manuscript comprehensively reviews the biosensing applications of graphene and its derivatives (i.e. GO and rGO). Prospects and challenges are also introduced.

Preliminary Study of Alginates Extracted from Brown Algae (Sargassum sp.) Available in Madura Island as Composite Based Hydrogel Materials

2019 ◽  
Vol 964 ◽  
pp. 240-245 ◽  
Author(s):  
Amaliya Rasyida ◽  
Thalyta Rizkha Pradipta ◽  
Sigit Tri Wicaksono ◽  
Vania Mitha Pratiwi ◽  
Yeny Widya Rakhmawati
Keyword(s):  
Sodium Alginate ◽  
Brown Algae ◽  
Extraction Process ◽  
Composition Analysis ◽  
3D Printer ◽  
X Ray Diffraction ◽  
X Ray ◽  
3D Printed ◽  
Preliminary Study

Utilization of brown algae especially in Madura, where it’s close to Surabaya, only limited for food. This become a reference for developing and increasing the potential of this algae by extracting one of the ingredients, namely alginate. This paper deals with the characterization of sodium alginate extracted from sargassum sp. using modified-purified calcium routes. The extracted sodium alginate will be further used as composite hydrogel materials and compared with commercial sodium alginate. Hereafter, the synthesized composite is expected to be bio-ink for 3d printer. Chemical composition analysis were analyzed using X-Ray Fluorosense (XRF) followed by Fourier-transform infrared spectroscopy (FTIR) analysis to identify the functional group of composite and X-Ray Diffraction (XRD). Furthermore, viscosity bath is performed to compare the viscosity of extracted and commercial one. The result shows that modified-purified calcium routes in the extraction process of sodium alginate is desirable for improving their properties. Interestingly enough, with the goal of using it as bio-ink in 3d printed fabrication, the synthesized composite shows viscosity, 300 cSt, which meets the criteria for bio-ink in 3d printer.

scholarly journals Characterization of micro-RNA in women with different ovarian reserve

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masood Abu-Halima ◽  
Lea Simone Becker ◽  
Basim M. Ayesh ◽  
Simona Lucia Baus ◽  
Amer Hamza ◽  
...  
Keyword(s):  
Ovarian Reserve ◽  
Independent Set ◽  
Micro Rna ◽  
Mirna Array ◽  
Reverse Transcription Quantitative Pcr ◽  
Diagnostic Approaches ◽  
Auc Value ◽  
Mirna Abundance

AbstractWomen undergoing infertility treatment are routinely subjected to one or more tests of ovarian reserve. Therefore, an adequate assessment of the ovarian reserve is necessary for the treatment. In this study, we aimed to characterize the potential role of microRNAs (miRNAs) as biomarkers for women with different ovarian reserves. A total of 159 women were recruited in the study and classified according to their anti-Müllerian hormone (AMH) level into three groups: (1) low ovarian reserve (LAMH, n = 39), (2) normal ovarian reserve (NAMH, n = 80), and (3) high ovarian reserve (HAMH, n = 40). SurePrint Human miRNA array screening and reverse transcription-quantitative PCR (RT-qPCR) were respectively employed to screen and validate the miRNA abundance level in the three tested groups. Compared with NAMH, the abundance level of 34 and 98 miRNAs was found to be significantly altered in LAMH and HAMH, respectively. The abundance level of miRNAs was further validated by RT-qPCR in both, the screening samples as well as in an independent set of validation samples. The abundance levels of the validated miRNAs were significantly correlated with the AMH level. The best AUC value for the prediction of the increase and decrease in the AMH level was obtained for the miR-100-5p and miR-21-5p, respectively. The level of miRNAs abundance correlates with the level of AMH, which may serve as a tool for identifying women with a different ovarian reserve and may help to lay the ground for the development of novel diagnostic approaches.

scholarly journals Activation and activity of glycosylated KLKs 3, 4 and 11

2018 ◽  
Vol 399 (9) ◽  
pp. 1009-1022 ◽  
Author(s):  
Shihui Guo ◽  
Peter Briza ◽  
Viktor Magdolen ◽  
Hans Brandstetter ◽  
Peter Goettig
Keyword(s):  
Physiological Function ◽  
Periodic Acid ◽  
Hek293 Cells ◽  
Secretory Expression ◽  
Detailed Characterization ◽  
Periodic Acid Schiff ◽  
Clinical Biomarkers ◽  
Schiff Reaction

Abstract Human kallikrein-related peptidases 3, 4, 11, and KLK2, the activator of KLK3/PSA, belong to the prostatic group of the KLKs, whose major physiological function is semen liquefaction during the fertilization process. Notably, these KLKs are upregulated in prostate cancer and are used as clinical biomarkers or have been proposed as therapeutic targets. However, this potential awaits a detailed characterization of these proteases. In order to study glycosylated prostatic KLKs resembling the natural proteases, we used Leishmania (LEXSY) and HEK293 cells for secretory expression. Both systems allowed the subsequent purification of soluble pro-KLK zymogens with correct propeptides and of the mature forms. Periodic acid-Schiff reaction, enzymatic deglycosylation assays, and mass spectrometry confirmed the glycosylation of these KLKs. Activation of glycosylated pro-KLKs 4 and 11 turned out to be most efficient by glycosylated KLK2 and KLK4, respectively. By comparing the glycosylated prostatic KLKs with their non-glycosylated counterparts from Escherichia coli, it was observed that the N-glycans stabilize the KLK proteases and change their activation profiles and their enzymatic activity to some extent. The functional role of glycosylation in prostate-specific KLKs could pave the way to a deeper understanding of their biology and to medical applications.

Experimental Characterization of CO2 and CaCO3 Used in a Pyrometallurgical Vanadium-Extraction Process

JOM ◽  
2019 ◽  
Vol 71 (12) ◽  
pp. 4925-4930 ◽  
Author(s):  
Wei-Tong Du ◽  
Qi Jiang ◽  
Zhuo Chen ◽  
Xiao-Ping Liang ◽  
Yu Wang
Keyword(s):  
Extraction Process ◽  
Experimental Characterization ◽  
Vanadium Extraction

scholarly journals Hypoxia and Macrophages Act in Concert Towards a Beneficial Outcome in Colon Cancer

Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 818
Author(s):  
Flávia Martins ◽  
Rosa Oliveira ◽  
Bruno Cavadas ◽  
Filipe Pinto ◽  
Ana Patrícia Cardoso ◽  
...  
Keyword(s):  
Colon Cancer ◽  
Cancer Cells ◽  
Colon Cancer Cells ◽  
Immune Markers ◽  
Lung Cancers ◽  
Inflammatory Phenotype ◽  
Cellular Components ◽  
Beneficial Outcome ◽  
Cell Crosstalk

In colon cancer, the prognostic value of macrophages is controversial, and it is still unknown how hypoxia modulates macrophage–cancer cell crosstalk. To unravel this, co-cultures of human primary macrophages and colon cancer cells were performed at 20% and 1% O2, followed by characterization of both cellular components. Different colon cancer patient cohorts were analyzed for hypoxia and immune markers, and their association with patient overall survival was established. A positive correlation between HIF1A and CD68 in colon cancer patients was identified but, unexpectedly, in cases with higher macrophage infiltration, HIF1A expression was associated with a better prognosis, in contrast to breast, gastric, and lung cancers. Under hypoxia, co-cultures’ secretome indicated a shift towards a pro-inflammatory phenotype. These alterations occurred along with increased macrophage phagocytic activity and decreased SIRPα expression. Cancer cells were more invasive and exhibited higher CD47 expression. We hypothesize that the better prognosis associated with HIF1AHighCD68High tumors could occur due to macrophagic pro-inflammatory pressure. Indeed, we found that tumors HIF1AHighCD68High expressed increased levels of CD8A, which is positively correlated with HIF1A. In conclusion, we show that in colon cancer, hypoxia drives macrophages into a pro-inflammatory phenotype, concomitant with increased infiltration of anti-tumor immune cells, favoring better disease outcome.

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