scholarly journals Sensitive Detection of Heregulin-α from Biological Samples Using a Disposable Stochastic Sensor Based on Plasma Deposition of GNPs–AgPs’ Nanofilms on Silk

Life ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 894
Author(s):  
Sorin Sebastian Gheorghe ◽  
Catalina Cioates Negut ◽  
Marius Badulescu ◽  
Raluca Ioana Stefan-van Staden
Keyword(s):  
Cold Plasma ◽  
Plasma Deposition ◽  
Screening Method ◽  
High Sensitivity ◽  
Active Surface ◽  
Screening Tests ◽  
Silver Particles ◽  
Tissue Samples ◽  
Disposable Sensor ◽  
Limit Of Determination

A composite material comprised of graphene nanoplatelet and silver particles (GNPs–AgPs) was used for the deposition of GNPs–AgPs’ nanofilms with cold plasma on silk. α-Cyclodextrin was used as a modifier of the active surface of the disposable sensor. The disposable stochastic sensor was used in screening tests for the assay of heregulin-α in whole blood and tissue samples. The disposable stochastic sensor showed a low limit of determination (4.10 fg mL−1) and can be used with high sensitivity on a wide concentration range (4.10 fg mL−1–0.04 µg mL−1). The screening method was validated against ELISA when good correlations (confirmed also by the t-test) were obtained.

scholarly journals Detection of enrofloxacine residues by microbiological screening method

2019 ◽  
Vol 35 (1) ◽  
pp. 49-59
Author(s):  
Jelena Petrovic ◽  
Brankica Kartalovic ◽  
Radomir Ratajac ◽  
Jasna Prodanov-Radulovic ◽  
Igor Stojanov ◽  
...  
Keyword(s):  
Screening Test ◽  
Screening Method ◽  
Detection Limits ◽  
Cost Effective ◽  
Antimicrobial Drug ◽  
Poultry Meat ◽  
Screening Tests ◽  
Tissue Samples ◽  
E Coli ◽  
Chicken Tissue

The usage of microbiological screening tests is widespread in control of presence of antimicrobial drug residues in meat samples. Screening tests must be capable to detect antimicrobial drug residue of interest and detection limits must comply with MRL (Maximum Residue Limit). The aim of this study was to examine the performance of a microbiological screening test with E. coli as test microorganism: capability of detecting enrofloxacina and it?s main metabolite ciprofloxacine at MRL levels in both fortified and incurred chicken tissue samples. Detection limits of microbiological screening test with E. coli was 50 ng/g for enrofloxacin and 25 ng/g for ciprofloxacin. Screening test had positive results in all samples of fortified and incurred meat with residue concentrations above MRL level. The results of this examinations shows that microbiological screening test with E. coli, as simple and cost effective test, is capable to detect enrofloxacine and it?s metabolite ciprofloxacine in treated poultry at MRL level ie test is capable to detect unsafe poultry meat.

A Novel Method for Microsatellite Instability Detection by Liquid Biopsy Based on Next- Generation Sequencing

2020 ◽  
Vol 15 ◽  
Author(s):  
Zheng Jiang ◽  
Hui Liu ◽  
Siwen Zhang ◽  
Jia Liu ◽  
Weitao Wang ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Microsatellite Instability ◽  
Liquid Biopsy ◽  
Tumor Tissue ◽  
High Sensitivity ◽  
Next Generation ◽  
Tissue Samples ◽  
Next Generation Sequencing Technology ◽  
Medication Selection ◽  
Generation Sequencing

Background: Microsatellite instability (MSI) is a prognostic biomarker used to guide medication selection in multiple cancers, such as colorectal cancer. Traditional PCR with capillary electrophoresis and next-generation sequencing using paired tumor tissue and leukocyte samples are the main approaches for MSI detection due to their high sensitivity and specificity. Currently, patient tissue samples are obtained through puncture or surgery, which causes injury and risk of concurrent disease, further illustrating the need for MSI detection by liquid biopsy. Methods: We propose an analytic method using paired plasma/leukocyte samples and MSI detection using next-generation sequencing technology. Based on the theoretical progress of oncogenesis, we hypothesized that the microsatellite site length in plasma equals the combination of the distribution of tumor tissue and leukocytes. Thus, we defined a window-judgement method to identify whether biomarkers were stable. Results: Compared to traditional PCR as the standard, we evaluated three methods in 20 samples (MSI-H:3/MSS:17): peak shifting method using tissue vs. leukocytes, peak shifting method using plasma vs. leukocytes, and our method using plasma vs. leukocytes. Compared to traditional PCR, we observed a sensitivity of 100%, 0%, and 100%, and a specificity of 100.00%, 94.12%, and 88.24%, respectively. Conclusion: Our method has the advantage of possibly detecting MSI in a liquid biopsy and provides a novel direction for future studies to increase the specificity of the method.

scholarly journals Cold Plasma Deposition of Polymeric Nanoprotrusion, Nanoparticles, and Nanofilm Structures on a Slide Glass Surface

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 99
Author(s):  
Sun-Woo Yi ◽  
In-Keun Yu ◽  
Woon-Jung Kim ◽  
Seong-Ho Choi
Keyword(s):  
Contact Angle ◽  
Visible Light ◽  
Methyl Methacrylate ◽  
Cold Plasma ◽  
Plasma Deposition ◽  
Vinyl Monomers ◽  
Glass Slides ◽  
Structure Surface ◽  
One Step ◽  
Coated Surface

In this study, we coated the surface of glass slides with nanoprotrusion, nanoparticles, and nanofilm structures by one-step plasma deposition of three vinyl monomers. Three functional vinyl monomers with symmetrical polarity sites were used: methyl methacrylate (MMA), trifluoro methylmethacrylate (TFMA), and trimethylsilyl methyl methacrylate (TSMA). The TSMA/MMA (80/20, mol-%) nanoprotrusion-coated surface of slide glass was superhydrophobic, with a 153° contact angle. We also evaluated the transmittance (%) of the slide glass with nanoprotrusions in the infrared (IR) (940 nm), ultraviolet (365 nm) and visible light (380–700 nm) regions. The obtained nanoprotrusion structure surface of slide glass created by plasma deposition transmits more than 90% of visible light.

scholarly journals Assessment of a change of protocol of prenatal screening by inclusion of non-invasive prenatal diagnosis

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Rocío Cabra-Rodríguez ◽  
Guadalupe Bueno Rodríguez ◽  
Cristina Santos Rosa ◽  
Miguel Ángel Castaño López ◽  
Sonia Delgado Muñoz ◽  
...  
Keyword(s):  
Prenatal Screening ◽  
Chromosomal Abnormalities ◽  
Screening Program ◽  
High Sensitivity ◽  
Maternal Blood ◽  
Screening Tests ◽  
Loss To Follow Up ◽  
Non Invasive ◽  
Second Trimester Screening ◽  
Trimester Screening

AbstractObjectivesNon-invasive prenatal screening (NIPS) is a test for the detection of major fetal chromosomal abnormalities in maternal blood during pregnancy. The purpose of this study was to assess the performance of NIPS implemented within the framework of the Screening Program for Congenital Abnormalities of the Andalusian Health System.MethodsA retrospective observational study was undertaken to determine the number of NIPS tests performed since its introduction. The number of invasive diagnostic tests done after the implementation of NIPS in the patients included in the program between March 2016 and August 2017 was also quantified.ResultsA total of 6,258 combined first- and second trimester screening tests were performed, covering 95% of the population. In total, 250 subjects were identified as high risk, of whom 200 underwent NIPS after loss to follow-up. NIPS showed a sensitivity of 100% (95% CI: 76.84–100%) and a specificity of 99.46% (95% CI: 97.04–99.99%).ConclusionsThis test has proven to have a very high sensitivity and specificity. The results obtained demonstrate that the incorporation of NIPS in clinical practice minimizes the rate of miscarriages and reduces the frequency of invasive procedures by 70%.

scholarly journals Linking a rapid throughput plate-assay with high-sensitivity stable-isotope label LCMS quantification permits the identification and characterisation of low β-L-ODAP grass pea lines

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Peter M. F. Emmrich ◽  
Martin Rejzek ◽  
Lionel Hill ◽  
Paul Brett ◽  
Anne Edwards ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Internal Standard ◽  
High Sensitivity ◽  
Spectrophotometric Assay ◽  
Rapid Screening ◽  
Grass Pea ◽  
Stable Isotope Label ◽  
Tissue Samples ◽  
Plate Assay ◽  
Accurate Quantification

Abstract Background Grass pea (Lathyrus sativus) is an underutilised crop with high tolerance to drought and flooding stress and potential for maintaining food and nutritional security in the face of climate change. The presence of the neurotoxin β-L-oxalyl-2,3-diaminopropionic acid (β-L-ODAP) in tissues of the plant has limited its adoption as a staple crop. To assist in the detection of material with very low neurotoxin toxin levels, we have developed two novel methods to assay ODAP. The first, a version of a widely used spectrophotometric assay, modified for increased throughput, permits rapid screening of large populations of germplasm for low toxin lines and the second is a novel, mass spectrometric procedure to detect very small quantities of ODAP for research purposes and characterisation of new varieties. Results A plate assay, based on an established spectrophotometric method enabling high-throughput ODAP measurements, is described. In addition, we describe a novel liquid chromatography mass spectrometry (LCMS)-based method for β-L-ODAP-quantification. This method utilises an internal standard (di-13C-labelled β-L-ODAP) allowing accurate quantification of β-L-ODAP in grass pea tissue samples. The synthesis of this standard is also described. The two methods are compared; the spectrophotometric assay lacked sensitivity and detected ODAP-like absorbance in chickpea and pea whereas the LCMS method did not detect any β-L-ODAP in these species. The LCMS method was also used to quantify β-L-ODAP accurately in different tissues of grass pea. Conclusions The plate-based spectrophotometric assay allows quantification of total ODAP in large numbers of samples, but its low sensitivity and inability to differentiate α- and β-L-ODAP limit its usefulness for accurate quantification in low-ODAP samples. Coupled to the use of a stable isotope internal standard with LCMS that allows accurate quantification of β-L-ODAP in grass pea samples with high sensitivity, these methods permit the identification and characterisation of grass pea lines with a very low ODAP content. The LCMS method is offered as a new ‘gold standard’ for β-L-ODAP quantification, especially for the validation of existing and novel low- and/or zero-β-L-ODAP genotypes.

scholarly journals High sensitivity sanger sequencing detection of BRAF mutations in metastatic melanoma FFPE tissue specimens

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lauren Y. Cheng ◽  
Lauren E. Haydu ◽  
Ping Song ◽  
Jianyi Nie ◽  
Michael T. Tetzlaff ◽  
...  
Keyword(s):  
Sanger Sequencing ◽  
Limit Of Detection ◽  
False Negative ◽  
High Sensitivity ◽  
Ffpe Tissue ◽  
Braf Mutations ◽  
Tissue Samples ◽  
Ffpe Samples ◽  
Droplet Pcr ◽  
Tissue Specimens

AbstractMutations in the BRAF gene at or near the p. V600 locus are informative for therapy selection, but current methods for analyzing FFPE tissue DNA generally have a limit of detection of 5% variant allele frequency (VAF), or are limited to the single variant (V600E). These can result in false negatives for samples with low VAFs due to low tumor content or subclonal heterogeneity, or harbor non-V600 mutations. Here, we show that Sanger sequencing using the NuProbe VarTrace BRAF assay, based on the Blocker Displacement Amplification (BDA) technology, is capable of detecting BRAF V600 mutations down to 0.20% VAF from FFPE lymph node tissue samples. Comparison experiments on adjacent tissue sections using BDA Sanger, immunohistochemistry (IHC), digital droplet PCR (ddPCR), and NGS showed 100% concordance among all 4 methods for samples with BRAF mutations at ≥ 1% VAF, though ddPCR did not distinguish the V600K mutation from the V600E mutation. BDA Sanger, ddPCR, and NGS (with orthogonal confirmation) were also pairwise concordant for lower VAF mutations down to 0.26% VAF, but IHC produced a false negative. Thus, we have shown that Sanger sequencing can be effective for rapid detection and quantitation of multiple low VAF BRAF mutations from FFPE samples. BDA Sanger method also enabled detection and quantitation of less frequent, potentially actionable non-V600 mutations as demonstrated by synthetic samples.

PREOPERATIVE ASSESSMENT OF VARIABLES TO PREDICT DIFFICULT INTUBATION IN PATIENTS UNDERGOING SURGERIES UNDER GENERAL ANAESTHESIA

2021 ◽  
pp. 68-71
Author(s):  
Veena Chatrath ◽  
Leena Mahajan ◽  
Gagandeep Kaur ◽  
Ankita Taneja ◽  
Ranjana Khetarpal ◽  
...  
Keyword(s):  
General Anaesthesia ◽  
Predictive Value ◽  
Prospective Observational Study ◽  
Risk Index ◽  
Preoperative Assessment ◽  
High Sensitivity ◽  
Screening Tests ◽  
Failed Intubation ◽  
Upper Lip ◽  
Number Of Patients

Background- Advance prediction of difcult airway provides us ample time for optimal preparation of equipment and participation of experienced anaesthesiologist to handle difcult airway. The present study was designed to evaluate the efcacy of Upper Lip Bite Test (ULBT), Ratio of neck circumference (NC) and thyromental distance (TMD) and Arne Risk Index in predicting difcult airway. Material and methods-This prospective observational study was conducted on 250 patients, aged 18-60 years of ASAgrade I and II scheduled for surgeries under general anaesthesia. Three screening tests i.e. ULBT, NC/TMD and Arne Risk Index were used to predict difcult airway. Number of patients successfully intubated, number of attempts taken for intubation and time taken for intubation was noted. Difcult intubation was calculated using Intubation Difculty Score (IDS). All the three screening tests were compared for their sensitivity, specicity, negative predictive value (NPV) and Positive predictive value (PPV) to predict difcult airway. Result- The incidence of difcult intubation was found to be 6.8%. 233 (95.2%) patients were intubated in rst attempt and 12 (4.8%) patients were intubated in second attempt and there was no failed intubation. Arne Risk Index had high sensitivity (88.23%), high specicity (88.84%), highest NPV (99.04%) and PPV of 36.58%. ULBThas sensitivity of 76.47%, specicity of 88.41%, NPV of 98.09% and PPV of 32.50% and NC/TMD has sensitivity of 47.05%, specicity of 87.98%, PPVof 22.22% and NPVof 95.79% in predicting difcult airway. Conclusion- Arne Risk index, a multivariate clinical risk index had highest sensitivity, specicity, NPVand PPVto predict difcult airway.

scholarly journals Evaluation of sodium lauryl sulfate for the development of cow-side mastitis screening test

2021 ◽  
pp. 2290-2295
Author(s):  
Nobonita Sarker Tanni ◽  
Md. Shafiul Islam ◽  
Mojahidul Kabir ◽  
Mst. Sonia Parvin ◽  
Md. Amimul Ehsan ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Sodium Lauryl Sulfate ◽  
Early Stage ◽  
High Sensitivity ◽  
Subclinical Mastitis ◽  
Screening Tests ◽  
Bromocresol Purple ◽  
Lauryl Sulfate ◽  
Operating Characteristics ◽  
Milk Samples

Background and Aim: Subclinical mastitis (SCM) is an economically important disease for dairy cattle worldwide; therefore, regular screening is imperative to detect SCM at an early stage so as to control it. The study was conducted to compare the test characteristics of sodium lauryl sulfate (SLS) as a test reagent to detect SCM in dairy cows. Materials and Methods: First, 106 milk samples of dairy cows were subjected to available indirect screening tests (white side test [WST], surf field mastitis test, Leucocytest, and Immucell) considering somatic cell count (SCC) as gold standard test. Then 273 milk samples were allowed to react with different concentrations of SLS with or without sodium hydroxide (NaOH) and indicators (bromothymol blue [BTB] and bromocresol purple [BCP]). Results: SLS with or without NaOH yielded best reaction with the milk samples similar to Leucocytest. It was observed that the reaction of milk samples with SLS added with indicators (BTB and BCP) was easier to visualize than without indicators. SLS 3%+NaOH 1.5% with BTB and SLS 2% with BCP had high sensitivity, specificity, and substantial agreement with SCC. The area under the receiver operating characteristics curve of SLS 2% with BCP and SLS 3%+NaOH 1.5% with BTB was 0.917 and 0.875, respectively. Conclusion: It may be concluded that SLS 3%+NaOH 1.5% with BTB and SLS 2% with BCP may be the potential reagents for the development of an effective cow-side test to detect SCM, as the main ingredient SLS is considerably cheap and readily available in developing countries.

scholarly journals Imaging Amyloid-β Deposits In Vivo

2002 ◽  
Vol 22 (9) ◽  
pp. 1035-1041 ◽  
Author(s):  
Brian J. Bacskai ◽  
William E. Klunk ◽  
Chester A. Mathis ◽  
Bradley T. Hyman
Keyword(s):  
Single Photon ◽  
Senile Plaques ◽  
Photon Emission ◽  
Multiphoton Microscopy ◽  
Amyloid Β ◽  
Neuronal Loss ◽  
High Sensitivity ◽  
Emission Computed Tomography ◽  
Tissue Samples

Alzheimer disease (AD) is an illness that can only be diagnosed with certainty with postmortem examination of brain tissue. Tissue samples from afflicted patients show neuronal loss, neurofibrillary tangles (NFTs), and amyloid-β plaques. An imaging technique that permitted in vivo detection of NFTs or amyloid-β plaques would be extremely valuable. For example, chronic imaging of senile plaques would provide a readout of the efficacy of experimental therapeutics aimed at removing these neuropathologic lesions. This review discusses the available techniques for imaging amyloid-β deposits in the intact brain, including magnetic resonance imaging, positron emission tomography, single photon emission computed tomography, and multiphoton microscopy. A variety of agents that target amyloid-β deposits specifically have been developed using one or several of these imaging modalities. The difficulty in developing these tools lies in the need for the agents to cross the blood-brain barrier while recognizing amyloid-β with high sensitivity and specificity. This review describes the progress in developing reagents suitable for in vivo imaging of senile plaques.

scholarly journals Prevalence and Characterization of Heterogeneous Vancomycin-Intermediate Staphylococcus aureus Isolates from 14 Cities in China

2009 ◽  
Vol 53 (9) ◽  
pp. 3642-3649 ◽  
Author(s):  
Wenjia Sun ◽  
Hongbin Chen ◽  
Yudong Liu ◽  
Chunjiang Zhao ◽  
Wright W. Nichols ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Population Analysis ◽  
Screening Method ◽  
Estimation Method ◽  
Area Under The Curve ◽  
Brain Heart Infusion ◽  
Screening Tests ◽  
Screening Methods ◽  
Large Numbers ◽  
Screening Cascade

ABSTRACT The prevalence of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) among 1,012 vancomycin-susceptible methicillin (meticillin)-resistant S. aureus isolates collected from 14 cities in China from 2005 to 2007 was 13 to 16%, as determined by a combination of (i) measurement by the modified population analysis profile-area under the curve method (PAP-AUC) and (ii) estimation from the measured sensitivity and specificity of a screening method. Two hundred isolates from blood were chosen as a subset for measurement of the sensitivities and the specificities of several previously described screening methods by using the results of PAP-AUC as the reference. During this testing, one isolate was found to be a vancomycin-intermediate S. aureus (VISA) strain so was not used in the evaluation of the screening tests. Of the other 199 isolates, 26 (13.1%) were hVISA, as assessed by PAP-AUC. A screening cascade of culturing the isolates on brain heart infusion agar containing teicoplanin (5 mg/liter) and then subjecting the positive isolates to a macro-Etest method was applied to the 812 non-blood isolates, yielding 149 positive results. From these results and by adjusting for sensitivity (0.423) and specificity (0.861), the prevalence was estimated to be 15.7%. The precision of that estimate was assessed by reapplying the screening cascade to 120 randomly selected isolates from the 812 non-blood isolates and simultaneously determining their heterogeneous vancomycin-intermediate susceptibility status by PAP-AUC. Because PAP-AUC is impractical for use with large numbers of isolates, the screening-based estimation method is useful as a first approximation of the prevalence of hVISA. Of the 27 VISA or hVISA isolates from blood, 22.2% and 74.1% were staphylococcal chromosome cassette mec types II and III, respectively, while 77.8% and 22.2% were agr type 1 and agr type 2, respectively; the MIC ranges were 0.5 to 4 mg/liter for vancomycin and 0.25 to 1 mg/liter for daptomycin.

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