scholarly journals Synthetic Antigen Gels as Practical Controls for Standardized and Quantitative Immunohistochemistry

2019 ◽  
Vol 67 (5) ◽  
pp. 309-334 ◽  
Author(s):  
Kathy J. Hötzel ◽  
Charles A. Havnar ◽  
Hai V. Ngu ◽  
Sandra Rost ◽  
Scot D. Liu ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Line ◽  
Protein Domains ◽  
Tissue Microarrays ◽  
Negative Control ◽  
Quantitative Immunohistochemistry ◽  
Synthetic Protein ◽  
Protein Gels ◽  
Control Samples

Optimization and standardization of immunohistochemistry (IHC) protocols within and between laboratories requires reproducible positive and negative control samples. In many situations, suitable tissue or cell line controls are not available. We demonstrate here a method to incorporate target antigens into synthetic protein gels that can serve as IHC controls. The method can use peptides, protein domains, or whole proteins as antigens, and is compatible with a variety of fixation protocols. The resulting gels can be used to create tissue microarrays (TMAs) with a range of antigen concentrations that can be used to objectively quantify and calibrate chromogenic, fluorescent, or mass spectrometry-based IHC protocols. The method offers an opportunity to objectively quantify IHC staining results, and to optimize and standardize IHC protocols within and between laboratories. (J Histochem Cytochem 58:XXX–XXX, 2019)

scholarly journals Determination and Confirmation of Pirlimycin Residue in Bovine Milk and Liver by Liquid Chromatography/Thermospray Mass Spectrometry: Interlaboratory Study

1996 ◽  
Vol 79 (5) ◽  
pp. 1054-1061 ◽  
Author(s):  
David N Heller ◽  
Jean Matusik ◽  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Bovine Milk ◽  
Internal Standard ◽  
Negative Control ◽  
The Third ◽  
Coefficients Of Variation ◽  
Residue Concentration ◽  
Thermospray Mass Spectrometry ◽  
Control Samples

Abstract Three laboratories participated in trials of methods to determine and confirm pirlimycin residue in bovine milk and liver. The methods used liquid chromatography/ thermospray mass spectrometry (LC/MS) with an internal standard to measure residue concentration. The internal standard was isopirlimycin, a stereoisomer of pirlimycin, which was resolved chromatographically. Determinative procedures were validated by replicate analyses of negative control, fortified control, and residue-incurred milk. For the milk method, average corrected recoveries (and coefficients of variation, CVs) were 83- 113% (CV, 7.5-15.4%) at 0.2 ppm, 91-98% (CV, 3.4- 18.5%) at 0.4 ppm, and 89-102% (CV, 8.8-22.9%) at 0.8 ppm. For the liver method, average corrected recoveries were 94-103% (CV, 2.2-7.1%) at 0.25 ppm, 87-94% (CV, 4.8-10.3%) at 0.5 ppm, and 96-101% (CV, 5.5-6.9%) at 1.0 ppm. There were no interferences in control samples of either matrix. Pirlimycin was confirmed by matching the retention time and relative abundances of 4 ions from sample extracts to corresponding values obtained for pirlimycin standard. Pirlimycin was confirmed in all residue- incurred samples and all samples fortified at regulatory tolerances (0.4 ppm in milk and 0.5 ppm in liver) by 2 of the 3 laboratories and in most samples by the third laboratory

Confirmation of Leucogentian Violet in Chicken Fat by Gas Chromatography/Mass Spectrometry

1994 ◽  
Vol 77 (5) ◽  
pp. 1137-1142
Author(s):  
Roger T Wilson ◽  
John Wong ◽  
John Johnston ◽  
Robert Epstein ◽  
David N Heller
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Organic Phase ◽  
Negative Control ◽  
Gas Chromatography Mass Spectrometry ◽  
Chicken Fat ◽  
Relative Abundances ◽  
Liquid Chromatographic ◽  
Control Samples ◽  
Chromatographic Mass

Abstract A gas chromatographic/mass spectrometry (GC/MS) procedure for confirming the identity of leucogentian violet (LGV) in chicken fat was developed for regulatory application. The unused portion of the extract remaining from a determinative procedure was back-extracted into an organic phase, concentrated, and analyzed by GC/MS. Confirmation of the identity of LGV was based on matching the retention times and relative abundances of 6 ions in the extract to corresponding values obtained for the LGV standard. The procedure was validated by replicate analyses of negative control, fortified control, and residue-incurred chicken fat. The presence of LGV was confirmed by the GC/MS procedure in all samples found to contain LGV by prior liquid chromatographic analyses. There were no interferences in the control samples.

scholarly journals The effect of NPM1 silencing on the tumorigenesis of drug-resistant bladder cancer and related signaling pathway

2020 ◽  
Author(s):  
Chenshuo Luo ◽  
Ting Lei ◽  
Man Zhao ◽  
Qian Meng ◽  
Zhang Man
Keyword(s):  
Mass Spectrometry ◽  
Bladder Cancer ◽  
Cell Line ◽  
Signaling Pathway ◽  
Nude Mice ◽  
Negative Control Group ◽  
Negative Control ◽  
Control Group ◽  
Migration Ability ◽  
Significant Difference

Abstract Background: NPM1 can provide abundant information of bladder cancer changes, but the effect of NPM1 differential expression on tumor and tumor related molecular mechanism has not been elucidated.Methods: NPM1 silencing cell line was established by lentivirus. The tumorigenic ability was judged by wound-healing assay, transwell invasion assay and nude mice tumorigenicity assay. The proteome of NPM1 deficient bladder cancer cell line was analyzed by Liquid Chromatography Mass Spectrometry (LC-MS). The results of mass spectrometry are comprehensively analyzed by bioinformatics analysis for tumor related molecules. The signal pathways involved in tumor related molecules will be verified by KEGG and UniProt databases.Results: Compared with the corresponding negative control group, NPM1 silencing cell line T24/DDP Lv-NPM1 showed strong migration ability and high invasive ability. There was no significant difference in migration ability and the invasive cells proportion between NPM1 overexpressing cell line and related negative control group. The tumorigenesis in nude mice also showed that NPM1 silencing tumor had larger tumor volume. Among all differential proteins analyzed by mass spectrometry, 20 proteins with signal transduction activity showed the most significant difference (Fold change > 1.5). 6 of them were associated with NF-κB signaling pathway, which may play an important role in the development of tumor.Conclusions: The loss of NPM1 may indicate the poor outcome of bladder cancer. Abnormal expression of NF-κB signaling pathway is an important factor in the progression of bladder cancer. Monitoring NPM1 expression can effectively adjust the treatment strategy of bladder cancer.

scholarly journals Automated Western immunoblotting detection of anti-SARS-CoV-2 serum antibodies

2021 ◽  
Author(s):  
Sophie Edouard ◽  
Rita Jaafar ◽  
Nicolas Orain ◽  
Philippe Parola ◽  
Philippe Colson ◽  
...  
Keyword(s):  
Negative Control ◽  
Cross Reactivity ◽  
Spike Protein ◽  
Rt Pcr ◽  
Substantial Agreement ◽  
Western Immunoblotting ◽  
Elisa Kit ◽  
Line Test ◽  
Serologic Assay ◽  
Control Samples

AbstractELISA and chemiluminescence serological assays for COVID-19 are currently incorporating only one or two SARS-CoV-2 antigens. We developed an automated Western immunoblotting as a complementary serologic assay for COVID-19. The JessTM Simple Western system, an automated capillary-based assay, was used, incorporating an inactivated SARS-CoV-2 lineage 20a strain as the source of antigen, and total immunoglobulins (IgG, IgM, IgA) detection. In total, 602 sera were tested including 223 from RT-PCR-confirmed COVID-19 patients, 76 from patients diagnosed with seasonal HCoVs and 303 from coronavirus-negative control sera. We also compared this assay with the EUROIMMUN® SARS-CoV-2 IgG ELISA kit. Among 223 sera obtained from RT-PCR-confirmed COVID-19 patients, 180/223 (81%) exhibited reactivity against the nucleocapsid and 70/223 (31%) against the spike protein. Nucleocapsid reactivity was further detected in 9/76 (14%) samples collected from patients diagnosed with seasonal HCoVs and in 15/303 (5%) coronavirus-negative control samples. In the subset of sera collected more than 2 weeks after the onset of symptoms, the sensitivity was 94% and the specificity 93%, the latter value probably reflecting cross-reactivity of SARS-CoV-2 with other coronaviruses. The automated Western immunoblotting presented a substantial agreement (90%) with the compared ELISA (Cohen’s Kappa=0.64). Automated Western immunoblotting may be used as a second line test to monitor exposure of people to HCoVs including SARS-CoV-2.

Gas chromatography-mass spectrometry fingerprint and in vitro cytotoxic studies of Rubus steudneri leaf fractions against michigan cancer foundation-7 breast cancer cell line

2021 ◽  
Vol 17 (5) ◽  
pp. 54
Author(s):  
RaghavendraLakshmana Shetty Hallur ◽  
ChaitanyaV. N L. Motamarri ◽  
PrashithKekuda T. Ramamoorthy ◽  
ChetanD Murthy ◽  
RavikumarPatil H. Siddappa ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Cell Line ◽  
Breast Cancer Cell ◽  
Breast Cancer Cell Line ◽  
Cancer Cell Line ◽  
Gas Chromatography Mass Spectrometry ◽  
Cytotoxic Studies

scholarly journals An Easily Overlooked Contamination of Syringes in Newborn Screening by Tandem Mass Spectrometry

2021 ◽  
Vol 8 ◽  
Author(s):  
Yanyun Wang ◽  
Yun Sun ◽  
Tao Jiang
Keyword(s):  
Mass Spectrometry ◽  
Quality Control ◽  
Tandem Mass Spectrometry ◽  
Newborn Screening ◽  
Retrospective Analysis ◽  
Tandem Mass ◽  
Patient Sample ◽  
Important Test ◽  
Control Samples

Background: Tandem mass spectrometry becomes a common and important test in newborn screening, but potential contamination of the equipment has largely been ignored.Methods: The source of contamination through Biosan quality control samples was examined prospectively, and further confirmed by retrospective analysis of patient samples.Results: We found that the source of contamination came from a syringe in the Biosan quality control samples. Furthermore, we found that a large number of indicators in the patient sample were interfered by syringe contamination in our center, and also in two other newborn screening centers, but the affected indicators were different in different screening centers.Conclusion: Syringe contamination will affect the detection of patient samples by tandem mass spectrometry and should be monitored carefully and immediately.

scholarly journals Ircinal E, a New Manzamine Derivative from the Indonesian Marine Sponge Acanthostrongylophora ingens

2015 ◽  
Vol 10 (11) ◽  
pp. 1934578X1501001 ◽  
Author(s):  
Mousa AlTarabeen ◽  
Georgios Daletos ◽  
Weaam Ebrahim ◽  
Werner E. G. Müller ◽  
Rudolf Hartmann ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Cell Line ◽  
Marine Sponge ◽  
High Resolution Mass Spectrometry ◽  
Two Dimensional ◽  
Meoh Extract ◽  
L5178y Cell ◽  
Resolution Mass

Chemical investigation of the MeOH extract of the sponge Acanthostrongylophora ingens afforded the new manzamine derivative ircinal E (1), in addition to six known metabolites (2–7). The structure of the new compound was unequivocally elucidated using one- and two-dimensional NMR spectroscopy, as well as high-resolution mass spectrometry. Compounds 1–6 exhibited strong to moderate cytotoxicity against the murine lymphoma L5178Y cell line with IC50 values ranging from 2.8 to 21.7 μM.

scholarly journals Anti-Bacterial Effect and Cytotoxicity Assessment of Lipid 430 Isolated from Algibacter sp.

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3991
Author(s):  
Yannik K.-H. Schneider ◽  
Kine Ø. Hansen ◽  
Johan Isaksson ◽  
Sara Ullsten ◽  
Espen H. Hansen ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Line ◽  
Melanoma Cell ◽  
Melanoma Cell Line ◽  
Barents Sea ◽  
Bioactive Compound ◽  
Active Principle ◽  
Resonance Spectroscopy ◽  
Nuclear Resonance Spectroscopy ◽  
Cytotoxicity Assessment

Two bacterial isolates from the Barents Sea, both belonging to the genus Algibacter, were found to yield extracts with anti-bacterial bioactivity. Mass spectrometry guided dereplication and purification of the active extracts lead to the isolation of the same active principle in both extracts. The structure of the bioactive compound was identified via mass spectrometry and nuclear resonance spectroscopy and it turned out to be the known lipopeptide Lipid 430. We discovered and determined its previously unknown anti-bacterial activity against Streptococcus agalactiae and revealed a cytotoxic effect against the A2058 human melanoma cell line at significantly lower concentrations compared to its anti-bacterial concentration. Flow cytometry and microscopy investigations of the cytotoxicity against the melanoma cell line indicated that Lipid 430 did not cause immediate cell lysis. The experiments with melanoma cells suggest that the compound functions trough more complex pathways than acting as a simple detergent.

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