187 OVARIAN CYCLE LIPID DYNAMICS REVEALED BY DESI-MS IMAGING AND MORPHOLOGICALLY-DRIVEN MULTIVARIATE STATISTICS

2015 ◽  
Vol 27 (1) ◽  
pp. 184
Author(s):  
A. K. Jarmusch ◽  
C. R. Ferreira ◽  
L. S. Eberlin ◽  
V. Pirro
Keyword(s):  
Multivariate Statistics ◽  
Ovarian Tissue ◽  
Univariate Analysis ◽  
Ambient Ionization ◽  
Negative Ion ◽  
Corpora Lutea ◽  
Ionization Mass ◽  
Ms Imaging ◽  
Adrenic Acid ◽  
Desi Ms

Understanding the role of lipid metabolism in ovarian physiology is crucial for the progression of reproductive biotechnology. The aim in this work was to explore the lipid composition and dynamics of ovarian tissue, specifically the stroma, follicles, and corpora lutea. Desorption electrospray ionization–mass spectrometry (DESI-MS), an ambient ionization technique, was applied in this investigation, acquiring chemical and spatial information simultaneously. A morphologically-friendly solvent, dimethylformamide-acetonitrile (1 : 1), was used for DESI-MS imaging which allowed for ovarian lipid characterisation and subsequent staining (hematoxylin and eosin) providing morphological information. By this approach, regions-of-interest (ROI) were selected from bovine (n = 8), swine (n = 3), and mice (n = 5) ovaries (including pre-pubescent and cycling adults) based on the stained morphological structures. ROI for stroma (n = 54), follicles (n = 89), and corpora lutea (n = 61) were selected and chemically profiled. Tissue sections (20 μm) were thaw mounted onto glass microscope slides and stored at –80°C until analysis. A linear ion trap mass spectrometer equipped with a custom DESI-MS imaging stage was operated in the negative ion mode (m/z 200 to 1000). A 300 × 300 µm pixel size was used in DESI-MS imaging of ovarian tissue. Hyperspectral DESI images were reconstructed and processed by principal component analysis (PCA) that allowed visualisation of relationships among spatial (i.e. morphology) and chemical features. Ions indicated by PCA were analysed using univariate analysis (ANOVA), supporting the significance of particular lipids between morphological structures, e.g. adrenic acid (P = 1.7 × 10–8) and m/z 836 (P = 8.9 × 10–9) between corpora lutea and follicles. All morphological structures could be differentiated by multivariate statistics (>90% prediction rate) independent of the species, indicating conserved lipid constitution. Smaller differences in the lipid profiles were noted between species, poly-ovulatory and mono-ovulatory species, and reproductive maturation. A large variety and abundance of lipids was observed in corpora lutea and follicles, where steroidogenesis is a prominent physiological activity. Additional insight into ovarian physiology was gained with the detection of arachidonic and adrenic acid. The spatial relationship of arachidonic and adrenic acid with the corpora lutea – the former is a known prostaglandin precursor and key signalling molecule in steroidogenesis regulation and the latter is metabolized in the prostaglandin pathway by the same enzymes – suggests the latter may also have a role in steroidogenesis regulation, previously unseen in ovarian physiology. DESI-MS imaging with morphologically-driven statistical analysis proved efficient in relating and interpreting the chemical and morphological features. This methodology can by further applied to unravel complex ovarian-related physiological mechanisms and to other physiological and physiopathological models.

scholarly journals 662. Identification of Clinically Relevant Microbes with the MasSpec Pen

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S386-S387
Author(s):  
Sydney C Povilaitis ◽  
Ashish D Chakraborty ◽  
Rachel D Downey ◽  
Sarmistha Bhaduri Hauger ◽  
Livia Eberlin
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectrometer ◽  
Model Performance ◽  
Sample Surface ◽  
Clinical Analysis ◽  
Ambient Ionization ◽  
Rapid Identification ◽  
Negative Ion ◽  
Ionization Mass ◽  
Molecular Features

Abstract Background In the age of antimicrobial resistance, rapid identification of infectious agents is critical for antimicrobial stewardship and effective therapy. To this end, ambient ionization mass spectrometry techniques have been applied for rapid identification of microbes directly from culture isolates. We have developed a handheld, mass spectrometry-based device, the MasSpec Pen, that permits direct molecular analysis of a biological sample in seconds (Scheme 1). Here, we employ the MasSpec Pen to identify clinically relevant microbes directly from culture isolates. Methods Staphylococcus aureus, Staphylococcus epidermidis, Group A and B Streptococcus, Kingella kingae (K.k), and Pseudomonas aeruginosa (P.a) were cultured on 5% sheep’s blood nutrient agar at 37 °C overnight. Colonies were transferred to a glass slide where they were analyzed directly with the MasSpec Pen coupled to a Q Exactive mass spectrometer (Thermo Scientific) in negative ion mode. For MasSpec Pen analysis, a 10 µL droplet of water was held in contact with the sample surface for 3 seconds and then aspirated to the mass spectrometer for analysis. Data was normalized and the molecular features resulting from the analysis solvent and nutrient medium were removed. The least absolute shrinkage and selection operator (lasso) statistical method was used to build classification models for prediction of bacterial identity. Model performance was evaluated by leave-one-out cross-validation and a validation set of samples. Scheme 1: MasSpec Pen workflow Results Various small molecules were detected including metabolites and glycerophospholipid species. The mass spectral profiles for each species exhibited qualitative differences among them (Figure 1). Additionally, several quorum-sensing molecules were observed in P.a. including hydroxy-heptyl-quinoline (m/z 242.155). Lasso statistical classifiers were created to differentiate organisms at the level of Gram type, genus, and species with each model comprised of a sparse set of molecular features. Accuracies of 90% or greater were achieved for all lasso models and as high as 98% for the differentiation of Staphylococcus (Staph.) and Streptococcus (Strep.). Figure 1: Molecular profiles of species analyzed Figure 2: Statistical classification results Conclusion These results demonstrate the potential of the MasSpec Pen as a tool for clinical analysis of infected biospecimens. Disclosures Sydney C. Povilaitis, BA, MS Pen Technologies, Inc. (Other Financial or Material Support, Patent) Livia Eberlin, PhD, MS Pen Technolpogies, Inc. (Board Member, Shareholder)

scholarly journals Peptide and Protein Assays Using Customizable Bio-Affinity Arrays Combined with Ambient Ionization Mass Spectrometry

2021 ◽  
Author(s):  
xuemeng zhang ◽  
Wei Wang ◽  
Richard N. Zare ◽  
Qianhao Min
Keyword(s):  
Mass Spectrometry ◽  
High Throughput ◽  
Desorption Electrospray Ionization ◽  
Ambient Ionization ◽  
Ionization Mass Spectrometry ◽  
Ionization Mass ◽  
Label Free ◽  
Ambient Ionization Mass Spectrometry ◽  
Desi Ms ◽  
Protein Assays

High-throughput identification and quantification of protein/peptide biomarkers from biofluids in a label-free manner is achieved by interfacing bio-affinity arrays (BAAs) with nano-electrospray desorption electrospray ionization mass spectrometry (nano-DESI-MS). A wide...

Mammalian ovarian lipid distributions by desorption electrospray ionization–mass spectrometry (DESI-MS) imaging

2020 ◽  
Vol 412 (6) ◽  
pp. 1251-1262 ◽  
Author(s):  
Fernanda Bertuccez Cordeiro ◽  
Alan K. Jarmusch ◽  
Marisol León ◽  
Christina Ramires Ferreira ◽  
Valentina Pirro ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Ionization ◽  
Electrospray Ionization Mass Spectrometry ◽  
Desorption Electrospray Ionization ◽  
Ionization Mass Spectrometry ◽  
Ionization Mass ◽  
Ms Imaging ◽  
Desi Ms

229 RAPID, UNTARGETED LIPID DETERMINATION IN INDIVIDUAL BOVINE OOCYTES AND PRE-IMPLANTATION EMBRYOS BY HIGH-RESOLUTION DESORPTION ELECTROSPRAY IONIZATION MASS SPECTROMETRY

2013 ◽  
Vol 25 (1) ◽  
pp. 262 ◽  
Author(s):  
A. F. González-Serrano ◽  
C. R. Ferreira ◽  
V. Pirro ◽  
L. S. Eberlin ◽  
J. Heinzmann ◽  
...  
Keyword(s):  
High Resolution ◽  
Desorption Electrospray Ionization ◽  
Fatty Acyl ◽  
Glass Slide ◽  
Negative Ion ◽  
Ionization Mass ◽  
Desi Ms ◽  
Negative Ion Mode ◽  
Bovine Oocytes ◽  
Positive Ion

Lipid structural analysis in individual pre-implantation mammalian embryos is hampered by the small amount of biological material, such that most studies use staining methods or gas chromatography analysis generate information only on the fatty acyl residues. Recent developments in high-resolution desorption electrospray ionization mass spectrometry (DESI-MS) allow the analysis of free fatty acids (FA) and glycerophospholipids (PL) in individual bovine embryos. Here, we report on the use of DESI-MS for the sensitive analysis of triacylglycerol (TAG) species, profiles of FA and PL in individual bovine oocytes and embryos. Bovine oocytes (n = 40) and blastocysts (n = 42) were frozen in a minimal volume of PBS (2 to 5 µL). Samples were directly deposited on glass slides after thawing. After drying, a volume of 500 µL of methanol : water (1 : 1, vol/vol) was carefully deposited on the surface of the glass slide and removed by orienting the glass slide vertically to eliminate PBS salts. An Orbitrap mass spectrometer was used for the experiments. Parameters for the positive ion mode were as follows: acetonitrile (ACN) supplemented with 3 µL mL–1 of AgNO3 at a 5 µL min–1 flow rate, injection time of 1000 ms, and a mass-to-charge range of m/z 400 to 1500. For the negative ion mode, the solvent combination used was acetonitrile + dimethylformamide (1 : 1, vol/vol) at a 1.0 µL min–1 flow rate, a maximum injection time of 1000 ms, and a mass-to-charge range of m/z 150 to 1000. Positive ion mode data for the detection of TAG species were acquired first, followed by acquisition of FA and PL in the negative ion mode. Detection of TAG by DESI, which is extremely useful for bovine embryo cryopreservation and metabolism research, has been performed by adding AgNO3 in the DESI spray to obtain silver adducts, which are easily recognised by the characteristic 1 : 1 abundance ratio of the 107 : 109 Ag isotopes. The most abundant fatty acyl residues present in TAG species were palmitic (P), linoleic (L), oleic (O), and stearic (S) acids, such as TAG of m/z 937, PPL (50 : 2); m/z 965, POO (52 : 1); m/z 967, POS (52 : 2); m/z 989, OOL/LLS (54 : 4); and m/z 991, OOO, SOL (54 : 3). Free FA and PL profiles collected from the same samples in the negative ion mode were similar to those in our recent report (2012 J. Mass Spectrom. 47, 29–33). Lipid attribution has been performed based on high-resolution mass analysis. Multivariate statistics from this data set will allow visualisation of differences observed in the lipid profiles among samples. In conclusion, we report the use of DESI-MS for the sensitive analysis of TAG in individual bovine oocytes and embryos and the creation of profiles of FA, PL, and TAG species in the same sample by DESI-MS.

Rapid detection of Fusarium wilt in basil (Ocimum sp.) leaves by desorption electrospray ionization mass spectrometry (DESI MS) imaging

RSC Advances ◽  
2015 ◽  
Vol 5 (62) ◽  
pp. 50512-50522 ◽  
Author(s):  
R. G. Hemalatha ◽  
Hemanta R. Naik ◽  
Vasundhara Mariappa ◽  
T. Pradeep
Keyword(s):  
Mass Spectrometry ◽  
Spatial Distribution ◽  
Electrospray Ionization ◽  
Electrospray Ionization Mass Spectrometry ◽  
Rapid Detection ◽  
Desorption Electrospray Ionization ◽  
Ionization Mass ◽  
Ambient Conditions ◽  
Ms Imaging ◽  
Desi Ms

A rapid method to unravel the spatial distribution ofFusarium/other pathogen-contamination in asymptomatic leaves under ambient conditions.

59 LIPID DYNAMICS IN THE EARLY EMBRYONIC DEVELOPMENT OF ZEBRAFISH BY DESORPTION ELECTROSPRAY IONIZATION MASS SPECTROMETRY IMAGING AND NANOELECTROSPRAY–MASS SPECTROMETRY

2016 ◽  
Vol 28 (2) ◽  
pp. 159
Author(s):  
A. K. Jarmusch ◽  
C. T. Mahapatra ◽  
V. Pirro ◽  
C. R. Ferreira ◽  
M. S. Sepúlveda
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Ionization ◽  
Early Development ◽  
Electrospray Ionization Mass Spectrometry ◽  
Desorption Electrospray Ionization ◽  
Yolk Sac ◽  
Ionization Mass ◽  
Ms Imaging ◽  
Desi Ms ◽  
Positive Ion

This study introduces a combination of mass spectrometry-based analytical approaches with little or no sample preparation for the study of zebrafish (Danio rerio) lipid metabolism during early development (0 through 96 h post-fertilization, hpf). Desorption electrospray ionization mass spectrometry (DESI-MS) imaging and nanoelectrospray (nESI) MS were used. Embryos (N = 107) were placed onto filter paper squares and analysed by DESI-MS imaging. Embryos were arranged in rows with each one corresponding to a different developmental time, so that each DESI-MS image contained arrays of samples at different hpf. After completion of DESI-MS acquisition, the arrays were cut into strips of paper, isolating each embryo, which was subsequently inserted into a nESI tip and analysed. All experiments were performed using a linear ion trap mass spectrometer. DESI-MS images were acquired in the positive ion mode using acetonitrile doped with 10 ppm AgNO3, which allowed for the detection of cytosolic neutral lipids, such as cholesteryl esters (CE), diacylglicerols (DAG), triacylglycerols (TAG), squalene, and ubiquinone. For the nESI, experiments were run in full mass scan and MS/MS, in both negative and positive ion mode, using a mixture of dimethylformamide and acetonitrile to detect membrane phospholipids (e.g. phosphatidylcholines and phosphatidylglycerols). Principal component analysis was used to explore DESI-MS images and nESI data in an unsupervised fashion. The combination of DESI-MS imaging, providing chemical and spatial location, and nanoESI, providing a broader and more extensive structural information, showed that the lipid content changes dramatically over the first days of development. Accumulation of DAG and TAG, which are usually concentrated in the embryos yolk sac as an important storage for early development, were observed between 0 and 48 hpf. Embryos at the intermediate phase of development (24 hpf) were distributed between those of 0 and 48 hpf, reflecting the dynamics associated with development and might be correlated with TAG consumption and de novo synthesis. After 72 and 96 hpf, samples differed from prior developmental stages by the content of squalene, ubiquinone, and CE 22 : 5 (overexpressed), while the TAG content decreased. Further decrease of TAGs and ubiquinone occurred between 72 and 96 hpf. These observations indicated that zebrafish embryos rely entirely on the yolk sac for the nutrients needed to sustain growth and survival during the first four days of development. Yolk lipids are the likely source of TAGs, as well as cholesterol, a required component of cell membranes and a precursor for bile acids. The abundance of ubiquinone can be tied to zebrafish embryo growth, differentiation and organogenesis, and activation of mitochondria.

Distinctive lipid profiles of human breast cancer and adjacent normal tissues by desorption electrospray ionization mass spectrometry imaging.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 1132-1132
Author(s):  
Diana L. Caragacianu ◽  
Xiaohui Liu ◽  
Isaiah Norton ◽  
Jennifer Ide ◽  
Andrea Richardson ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Mass Spectrometry ◽  
Normal Tissue ◽  
Mass Spectrometry Imaging ◽  
Desorption Electrospray Ionization ◽  
Cancer Tissue ◽  
Ionization Mass ◽  
Proof Of Concept ◽  
Ms Imaging ◽  
Desi Ms

1132 Background: Routine intra-operative distinction between normal breast tissue and tumor is currently not possible in breast conserving surgery (BCS). This limitation affects the success of surgery, resulting in up to 40% requiring more than one operative procedure. Desorption electrospray ionization mass spectrometry (DESI MS) has been successfully used to discriminate between normal and cancerous human tissues from anatomical sites such as the liver and brain. The aim of this proof of concept study was to determine the feasibility of using DESI MS imaging for tissue identification and differentiation of breast cancer versus normal tissue. Methods: DESI MS imaging was carried out on 14 human invasive breast cancer samples. Breast cancer and adjacent normal paired human tissue sections (margin of tumor, 2cm and 5 cm from tumor) from 14 patients undergoing mastectomy were flash frozen in liquid nitrogen, sectioned, and thaw mounted to glass slides. All samples were imaged using DESI MS at 200 μm imaging resolution. DESI MS images were overlaid and compared with hematoxylin and eosin (H&E) images of the same sections. Results: Discrimination between cancer and adjacent normal tissue was achieved on the basis of the spatial distribution and varying intensities of particular fatty acids and lipid species. Several fatty acids such as oleic acid (m/z 281) and arachidonic acid (m/z 303) displayed much greater signal intensities in the cancer specimen compared to low or undetectable intensities in normal tissue. The cancer margins delineated by the DESI MS images of these molecules were consistent with H and E images of the tumor edge. Cancerous tissue was distinguished from normal tissue based on the qualitative assessment of molecular signatures and the distinction was in agreement with expert histopathology evaluation in 85% of samples. Conclusions: Our findings offer proof of concept that examination and classification of breast normal and cancer tissue by mass spectrometry imaging is highly accurate. The results are encouraging for development of a MS-based method that could be utilized intra-operatively for rapid detection of residual cancer tissue in the lumpectomy bed in BCS.

scholarly journals Molecular Imaging of Endometriosis Tissues using Desorption Electrospray Ionization Mass Spectrometry

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Clara L. Feider ◽  
Spencer Woody ◽  
Suzanne Ledet ◽  
Jialing Zhang ◽  
Katherine Sebastian ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Ionization ◽  
Desorption Electrospray Ionization ◽  
Test Sample ◽  
Ionization Mass ◽  
Imaging Data ◽  
Tissue Samples ◽  
Metabolic Markers ◽  
Ms Imaging ◽  
Desi Ms

Abstract Endometriosis is a pathologic condition affecting approximately 10% of women in their reproductive years. Characterized by abnormal growth of uterine endometrial tissue in other body areas, endometriosis can cause severe abdominal pain and/or infertility. Despite devastating consequences to patients’ quality of life, the causes of endometriosis are not fully understood and validated diagnostic markers for endometriosis have not been identified. Molecular analyses of ectopic and eutopic endometrial tissues could lead to enhanced understanding of the disease. Here, we apply desorption electrospray ionization (DESI) mass spectrometry (MS) imaging to chemically and spatially characterize the molecular profiles of 231 eutopic and ectopic endometrial tissues from 89 endometriosis patients. DESI-MS imaging allowed clear visualization of endometrial glandular and stromal regions within tissue samples. Statistical models built from DESI-MS imaging data allowed classification of endometriosis lesions with overall accuracies of 89.4%, 98.4%, and 98.8% on training, validation, and test sample sets, respectively. Further, molecular markers that are significantly altered in ectopic endometrial tissues when compared to eutopic tissues were identified, including fatty acids and glycerophosphoserines. Our study showcases the value of MS imaging to investigate the molecular composition of endometriosis lesions and pinpoints metabolic markers that may provide new knowledge on disease pathogenesis.

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