A peptide immunoaffinity LC–MS/MS strategy for quantifying the GPCR protein, S1PR1 in human colon biopsies

Background: S1PR1, a G protein-coupled receptor (GPCR) protein, is a therapeutic target for treatment of autoimmune diseases. As a potential biomarker for drug effect and patient stratification, it is of great significance to measure it in biological samples. However, due to the hydrophobic nature of S1PR1 and the difficulties in extraction and solubilization, as well as low expression levels, quantitative determination of S1PR1 remains challenging. Results: In this work, a peptide immunoaffinity LC–MS/MS method was developed to quantify S1PR1 in biopsy-sized colon samples with an LLOQ of 7.81 pM. Conclusion: Peptide immunoaffinity LC–MS/MS based strategy has achieved the desired sensitivity for low abundance S1PR1, and the same strategy could be applied to quantify S1PR1 in multiple species and other GPCR proteins.

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Advances in LC–MS/MS Methods for Allergen Testing, Meat Speciation, and Gelatin Speciation

Journal of AOAC International ◽

10.1093/jaoac/102.5.1309 ◽

2019 ◽

Vol 102 (5) ◽

pp. 1309-1315

Author(s):

Jianru Stahl-Zeng ◽

Ashley Sage ◽

Philip Taylor ◽

Jeremy Dietrich Netto ◽

Tuo Zhang

Keyword(s):

Mass Spectrometer ◽

Multiple Reaction Monitoring ◽

Proteome Analysis ◽

Food Product ◽

Transition Analysis ◽

Tandem Quadrupole Mass Spectrometer ◽

Signature Peptides ◽

Unique Markers ◽

Multiple Species

Abstract Background: Food authenticity is demanded by the consumer at all times. The consumer places trust in the manufacturer that the food product is genuine in terms of what is recorded on the packaging label. Objective: Recent advancements in LC–tandem MS methodology in the detection of allergens, meat, and gelatin speciation in raw food products and processed foods are detailed in this paper. Method: For each of the three methods, initial proteome analysis and the screening leading to the determination of unique tryptic peptides were conducted using a high-resolution, accurate tandem mass spectrometer. Having identified the unique markers, the method was transferred to a tandem quadrupole mass spectrometer for a higher-sensitivity quantitative study, multiple reaction monitoring transition analysis. Results: For the allergens method a detection limit of at least 10 ppm was attained across the 12 allergen peptides in this workflow. In the gluten workflow the resulting chromatograms show good detection down to 5 ppm, with no interference from the food matrices. The meat speciation method details that signature peptides could be readily identified at 1% w/w with no matrix interference. Conclusions: These single-injection workflows with cycle-time optimization enable wide coverage of analytes to identify multiple species within challenging matrix samples.

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O XVII B.2 Determination of endogenous DNA damage, oxidated DNA bases and oxidative stress in primary human colon cells and modulation by plant ingredients

Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis ◽

10.1016/s0027-5107(97)83211-3 ◽

1997 ◽

Vol 379 (1) ◽

pp. S171

Author(s):

Beatrice L. Pool-Zobel ◽

Salomon L. Abrahamse ◽

Daniela Oberreuther ◽

Sylvia Treptow-van Lishaut ◽

Gerhard Rechkemmer

Keyword(s):

Oxidative Stress ◽

Dna Damage ◽

Human Colon ◽

Dna Bases ◽

Colon Cells ◽

And Oxidative Stress

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Comparison of Three Solid Phase Materials for the Extraction of Carboxylic Acids from River Water Followed by 2D GC × GC-TOFMS Determination

International Journal of Analytical Chemistry ◽

10.1155/2016/6396938 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

G. O. Bosire ◽

J. C. Ngila ◽

H. Parshotam

Keyword(s):

Carboxylic Acid ◽

Carboxylic Acids ◽

Natural Organic Matter ◽

Solid Phase ◽

Cooling Water ◽

Raw Water ◽

Aliphatic Carboxylic Acid ◽

Hydrophobic Nature ◽

Relationship Of

The extraction and determination of aliphatic and aromatic carboxylic acids as well as their influence on the aromaticity and molecularity relationship of natural organic matter (NOM) in water are reported in this study. Three solid phase extraction (SPE) sorbents were used and their extraction efficiencies evaluated after chromatographic determinations (using gas chromatography with a time of flight mass spectrometer (GC × GC-TOFMS) and liquid chromatography with organic carbon detector (LC-OCD)). More than 42 carboxylic acids were identified in raw water from the Vaal River, which feeds the Lethabo Power Generation Station, South Africa, with cooling water. The aromatic carboxylic acid efficiency (28%) was achieved by using Strata™X SPE while the highest aliphatic carboxylic acid efficiency (92.08%) was achieved by silica SPE. The hydrophobic nature of NOM in water depends on the nature of organic compounds in water, whether aromatic or aliphatic. The LC-OCD was used to assess the hydrophobicity levels of NOM as a function of these carboxylic acids in cooling water. The LC-OCD results showed that the aromatic nature of NOM in SPE filtered water followed the order Silica>Strata X>C-18. From the results, the hydrophobicity degree of the samples depended on the type and number of carboxylic acids that were removed by the SPE cartridges.

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Is there a relation between serum methylarginine levels and infertility?

Hormone Molecular Biology and Clinical Investigation ◽

10.1515/hmbci-2020-0083 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Yasin Saygın ◽

Abdullah Sivrikaya ◽

Turan Akdağ ◽

Duygu Dursunoğlu ◽

Mehmet Kaynar ◽

...

Keyword(s):

Sperm Concentration ◽

Reproductive Period ◽

Healthy Individuals ◽

Adma Level ◽

Chromatography Tandem Mass Spectrometry ◽

Potential Biomarker ◽

Liquid Chromatography Tandem Mass ◽

Arginine Residues ◽

Dimethyl Arginine

Abstract Objectives Infertility is defined as the absence of pregnancy within the reproductive period despite regular sexual intercourse. Methylarginines are formed as a result of methylation of arginine residues in proteins and formed in three forms as asymmetric dimethyl arginine (ADMA), symmetrical dimethyl arginine (SDMA) and monomethylarginine (L-NMMA). So, here, we aimed to evaluate arginine and their derivatives levels in fertile and infertile individuals. Methods Present study were consist of 30 oligozoospermia patients (proven by spermiogram analysis) and 30 healthy individuals with normozoospermia group who were applied to the urology department. With blood samples taken from individuals, serum methylarginine and its derivatives levels were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Clinic data and demographic characteristics of individuals were also recorded at the same time. Results The serum ADMA level (0.38 ± 0.07) of the oligozoospermia group was found to be significantly higher than the normozoospermia group (0.35 ± 0.05) (p=0.046). A positive correlation were observed between ADMA and SDMA (r=0.686, p=0.000), HArg and SDMA (r=0.611, p=0.001), citrulline and L-NMMA (r=0.595, p=0.001) in patients with oligosospermia. The increase in SDMA, arginine and HArg levels and a decrease in L-NMMA and citrulline levels were not significant as statistically. Also, the ADMA level was found to be high in individuals with low sperm concentration. Conclusions Consequently, serum ADMA levels of individuals with oligozoospermia were statistically significantly higher than those with normozoospermia. As proposal, determination of ADMA levels may be a potential biomarker parameter in terms of early diagnosis of fertility and infertility.

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Determination of cell death induced by lovastatin on human colon cell line HT29 using comet assay

Toxicology Letters ◽

10.1016/j.toxlet.2011.05.419 ◽

2011 ◽

Vol 205 ◽

pp. S116-S117

Author(s):

M. Rezaei ◽

H. Kalantari ◽

M. HashemiTabar ◽

M. Jafari ◽

Z. Bahadori

Keyword(s):

Cell Death ◽

Comet Assay ◽

Cell Line ◽

Human Colon ◽

Human Colon Cell Line ◽

Colon Cell ◽

Colon Cell Line

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Down-Regulation of LncRNA DGCR5 Correlates with Poor Prognosis in Hepatocellular Carcinoma

Cellular Physiology and Biochemistry ◽

10.1159/000452582 ◽

2016 ◽

Vol 40 (3-4) ◽

pp. 707-715 ◽

Cited By ~ 45

Author(s):

Ruyi Huang ◽

Xiaochen Wang ◽

Wenjie Zhang ◽

Guangyan Zhangyuan ◽

Kangpeng Jin ◽

...

Keyword(s):

Roc Curve ◽

Cox Regression ◽

Cancer Specific Survival ◽

Term Survival ◽

Diagnosis And Prognosis ◽

Kaplan Meier ◽

High Expression Group ◽

Negative Prognostic Factor ◽

Potential Biomarker ◽

Low Expression

Background/Aims: Long non-coding RNAs (lncRNAs) have been reported to play pivotal roles in multiple tumors and can act as tumor biomarkers. In this study, we explored the association of the expression of an lncRNA, DGCR5 with clinicopathological features and prognosis in HCC. Methods: Expression levels of DGCR5 were detected by quantitative real-time PCR (qRT-PCR) and the clinical data was obtained, including basic information, data of clinicopathology and cancer specific survival rate. Receiver operating characteristic (ROC) curve, Kaplan-Meier methods and multivariable Cox regression models were used to analyze predictive efficiency, long-term survival outcomes and risk factors. Results: DGCR5 was found down-regulated in HCC tissues (P<0.001) and serum (P = 0.0035) and low expression of DGCR5 was correlated with a poor cancer specific survival (CSS) (P = 0.0019), as the overall 5-year CSS rates were 10.3% (low expression group) and 36.6% (high expression group), respectively. A stratified analysis demonstrated that low DGCR5 expression was an independent negative prognostic factor for HCC. In addition, the area under the ROC curve was 0.782 with a sensitivity of 0.633 and a specificity of 0.833. Conclusions: Our results suggest that DGCR5 may be a participator in HCC and can serve as potential biomarker for the diagnosis and prognosis in HCC.

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Out-of-the-groove transport of lipids by TMEM16 and GPCR scramblases

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1806721115 ◽

2018 ◽

Vol 115 (30) ◽

pp. E7033-E7042 ◽

Cited By ~ 20

Author(s):

Mattia Malvezzi ◽

Kiran K. Andra ◽

Kalpana Pandey ◽

Byoung-Cheol Lee ◽

Maria E. Falzone ◽

...

Keyword(s):

Polyethylene Glycol ◽

G Protein ◽

Credit Card ◽

Protein Families ◽

G Protein Coupled Receptor ◽

Physiological Processes ◽

Phospholipid Scrambling ◽

Conformational Rearrangements ◽

G Protein Coupled ◽

Gpcr Protein

Phospholipid scramblases externalize phosphatidylserine to facilitate numerous physiological processes. Several members of the structurally unrelated TMEM16 and G protein-coupled receptor (GPCR) protein families mediate phospholipid scrambling. The structure of a TMEM16 scramblase shows a membrane-exposed hydrophilic cavity, suggesting that scrambling occurs via the ‟credit-card” mechanism where lipid headgroups permeate through the cavity while their tails remain associated with the membrane core. Here we show that afTMEM16 and opsin, representatives of the TMEM16 and GCPR scramblase families, transport phospholipids with polyethylene glycol headgroups whose globular dimensions are much larger than the width of the cavity. This suggests that transport of these large headgroups occurs outside rather than within the cavity. These large lipids are scrambled at rates comparable to those of normal phospholipids and their presence in the reconstituted vesicles promotes scrambling of normal phospholipids. This suggests that both large and small phospholipids can move outside the cavity. We propose that the conformational rearrangements underlying TMEM16- and GPCR-mediated credit-card scrambling locally deform the membrane to allow transbilayer lipid translocation outside the cavity and that both mechanisms underlie transport of normal phospholipids.

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