Spatial Lipidomics Maps Brain Alterations Associated with Mild Traumatic Brain Injury

Traumatic brain injury (TBI) is a global public health problem with 50-60 million incidents per year, most of which are considered mild (mTBI) and many of these repetitive (rmTBI). Despite their massive implications, the pathologies of mTBI and rmTBI are not fully understood, with a paucity of information on brain lipid dysregulation following mild injury event(s). To gain more insight on mTBI and rmTBI pathology, a non-targeted spatial lipidomics workflow utilizing ultrahigh resolution mass spectrometry imaging was developed to map brain region-specific lipid alterations in rats following injury. Discriminant multivariate models were created for regions of interest including the hippocampus, cortex, and corpus callosum to pinpoint lipid species that differentiated between injured and sham animals. A multivariate model focused on the hippocampus region differentiated injured brain tissues with an area under the curve of 0.994 using only four lipid species. Lipid classes that were consistently discriminant included polyunsaturated fatty acid-containing phosphatidylcholines (PC), lysophosphatidylcholines (LPC), LPC-plasmalogens (LPC-P) and PC potassium adducts. Many of the polyunsaturated fatty acid-containing PC and LPC-P selected have never been previously reported as altered in mTBI. The observed lipid alterations indicate that neuroinflammation, oxidative stress and disrupted sodium-potassium pumps are important pathologies that could serve to explain cognitive deficits associated with rmTBI. Therapeutics which target or attenuate these pathologies may be beneficial to limit persistent damage following a mild brain injury event.

Divergent Skeletal Muscle Metabolomic Signatures of Different Exercise Training Modes Independently Predict Cardiometabolic Risk Factors

We investigated the link between enhancement of SI (by hyperinsulinemic-euglycemic clamp) and muscle metabolites after 12 weeks of aerobic (high-intensity interval training [HIIT]), resistance training (RT), or combined training (CT) exercise in 52 lean healthy individuals. Muscle RNA sequencing revealed a significant association between SI after both HIIT and RT and the branched-chain amino acid (BCAA) metabolic pathway. Concurrently with increased expression and activity of branched-chain ketoacid dehydrogenase enzyme, many muscle amino metabolites, including BCAAs, glutamate, phenylalanine, aspartate, asparagine, methionine, and γ-aminobutyric acid, increased with HIIT, supporting the substantial impact of HIIT on amino acid metabolism. Short-chain C3 and C5 acylcarnitines were reduced in muscle with all three training modes, but unlike RT, both HIIT and CT increased tricarboxylic acid metabolites and cardiolipins, supporting greater mitochondrial activity with aerobic training. Conversely, RT and CT increased more plasma membrane phospholipids than HIIT, suggesting a resistance exercise effect on cellular membrane protection against environmental damage. Sex and age contributed modestly to the exercise-induced changes in metabolites and their association with cardiometabolic parameters. Integrated transcriptomic and metabolomic analyses suggest various clusters of genes and metabolites are involved in distinct effects of HIIT, RT, and CT. These distinct metabolic signatures of different exercise modes independently link each type of exercise training to improved SI and cardiometabolic risk.

ARTICLE HIGHLIGHTS

We aimed to understand the link between skeletal muscle metabolites and cardiometabolic health after exercise training. Although aerobic, resistance, and combined exercise training each enhance muscle insulin sensitivity as well as other cardiometabolic parameters, they disparately alter amino and citric acid metabolites as well as the lipidome, linking these metabolomic changes independently to the improvement of cardiometabolic risks with each exercise training mode. These findings reveal an important layer of the unique exercise mode-dependent changes in muscle metabolism, which may eventually lead to more informed exercise prescription for improving SI.

The unknown lipids project: harmonized methods improve compound identification and data reproducibility in an inter-laboratory untargeted lipidomics study

Untargeted lipidomics allows analysis of a broader range of lipids than targeted methods and permits discovery of unknown compounds. Previous ring trials have evaluated the reproducibility of targeted lipidomics methods, but inter-laboratory comparison of compound identification and unknown feature detection in untargeted lipidomics has not been attempted. To address this gap, five laboratories analyzed a set of mammalian tissue and biofluid reference samples using both their own untargeted lipidomics procedures and a common chromatographic and data analysis method. While both methods yielded informative data, the common method improved chromatographic reproducibility and resulted in detection of more shared features between labs. Spectral search against the LipidBlast in silico library enabled identification of over 2,000 unique lipids. Further examination of LC-MS/MS and ion mobility data, aided by hybrid search and spectral networking analysis, revealed spectral and chromatographic patterns useful for classification of unknown features, a subset of which were highly reproducible between labs. Overall, our method offers enhanced compound identification performance compared to targeted lipidomics, demonstrates the potential of harmonized methods to improve inter-site reproducibility for quantitation and feature alignment, and can serve as a reference to aid future annotation of untargeted lipidomics data.

The mitochondrial multi-omic response to exercise training across tissues

Mitochondria are adaptable organelles with diverse cellular functions critical to whole-body metabolic homeostasis. While chronic endurance exercise training is known to alter mitochondrial activity, these adaptations have not yet been systematically characterized. Here, the Molecular Transducers of Physical Activity Consortium (MoTrPAC) mapped the longitudinal, multi-omic changes in mitochondrial analytes across 19 tissues in male and female rats endurance trained for 1, 2, 4 or 8 weeks. Training elicited substantial changes in the adrenal gland, brown adipose, colon, heart and skeletal muscle, while we detected mild responses in the brain, lung, small intestine and testes. The colon response was characterized by non-linear dynamics that resulted in upregulation of mitochondrial function that was more prominent in females. Brown adipose and adrenal tissues were characterized by substantial downregulation of mitochondrial pathways. Training induced a previously unrecognized robust upregulation of mitochondrial protein abundance and acetylation in the liver, and a concomitant shift in lipid metabolism. The striated muscles demonstrated a highly coordinated response to increase oxidative capacity, with the majority of changes occurring in protein abundance and post-translational modifications. We identified exercise upregulated networks that are downregulated in human type 2 diabetes and liver cirrhosis. In both cases HSD17B10, a central dehydrogenase in multiple metabolic pathways and mitochondrial tRNA maturation, was the main hub. In summary, we provide a multi-omic, cross-tissue atlas of the mitochondrial response to training and identify candidates for prevention of disease-associated mitochondrial dysfunction.

Field detection devices for screening the quality of medicines: a systematic review

BACKGROUND

Poor quality medicines have devastating consequences. A plethora of innovative portable devices to screen for poor quality medicines has become available, leading to hope that they could empower medicine inspectors and enhance surveillance. However, information comparing these new technologies is woefully scarce.

METHODS

We undertook a systematic review of Embase, PubMed, Web of Science and SciFinder databases up to 30 April 2018. Scientific studies evaluating the performances/abilities of portable devices to assess any aspect of the quality of pharmaceutical products were included.

RESULTS

Forty-one devices, from small benchtop spectrometers to 'lab-on-a-chip' single-use devices, with prices ranging from US$20 000, were included. Only six devices had been field-tested (GPHF-Minilab, CD3/CD3+, TruScan RM, lateral flow dipstick immunoassay, CBEx and Speedy Breedy). The median (range) number of active pharmaceutical ingredients (APIs) assessed per device was only 2 (1-20). The majority of devices showed promise to distinguish genuine from falsified medicines. Devices with the potential to assay API (semi)-quantitatively required consumables and were destructive (GPHF-Minilab, PharmaChk, aPADs, lateral flow immunoassay dipsticks, paper-based microfluidic strip and capillary electrophoresis), except for spectroscopic devices. However, the 10 spectroscopic devices tested for their abilities to quantitate APIs required processing complex API-specific calibration models. Scientific evidence of the ability of the devices to accurately test liquid, capsule or topical formulations, or to distinguish between chiral molecules, was limited. There was no comment on cost-effectiveness and little information on where in the pharmaceutical supply chain these devices could be best deployed.

CONCLUSION

Although a diverse range of portable field detection devices for medicines quality screening is available, there is a vitally important lack of independent evaluation of the majority of devices, particularly in field settings. Intensive research is needed in order to inform national medicines regulatory authorities of the optimal choice of device(s) to combat poor quality medicines.

Prevalence of substandard and falsified artemisinin-based combination antimalarial medicines on Bioko Island, Equatorial Guinea

Introduction

Poor-quality artemisinin-containing antimalarials (ACAs), including falsified and substandard formulations, pose serious health concerns in malaria endemic countries. They can harm patients, contribute to the rise in drug resistance and increase the public’s mistrust of health systems. Systematic assessment of drug quality is needed to gain knowledge on the prevalence of the problem, to provide Ministries of Health with evidence on which local regulators can take action.

Methods

We used three sampling approaches to purchase 677 ACAs from 278 outlets on Bioko Island, Equatorial Guinea as follows: convenience survey using mystery client (n=16 outlets, 31 samples), full island-wide survey using mystery client (n=174 outlets, 368 samples) and randomised survey using an overt sampling approach (n=88 outlets, 278 samples). The stated active pharmaceutical ingredients (SAPIs) were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories.

Results

Content analysis showed 91.0% of ACAs were of acceptable quality, 1.6% were substandard and 7.4% falsified. No degraded medicines were detected. The prevalence of medicines without the SAPIs was higher for ACAs purchased in the convenience survey compared with the estimates obtained using the full island-wide survey-mystery client and randomised-overt sampling approaches. Comparable results were obtained for full island survey-mystery client and randomised overt.

However, the availability of purchased artesunate monotherapies differed substantially according to the sampling approach used (convenience, 45.2%; full island-wide survey-mystery client, 32.6%; random-overt sampling approach, 21.9%). Of concern is that 37.1% (n=62) of these were falsified.

Conclusion

Falsified ACAs were found on Bioko Island, with the prevalence ranging between 6.1% and 16.1%, depending on the sampling method used. These findings underscore the vital need for national authorities to track the scale of ineffective medicines that jeopardise treatment of life-threatening diseases and value of a representative sampling approach to obtain/measure the true prevalence of poor-quality medicines.

Quality of Artemisinin-based Combination Therapy for malaria found in Ghanaian markets and public health implications of their use

Background

Ghana changed their antimalarial drug policy from monotherapies to Artemisinin-based Combination Therapies in 2004 in order to provide more efficacious medicines for treatment of malaria. The policy change can be eroded if poor quality Artemisinin-based Combination Therapies are allowed to remain on the Ghanaian market unchecked by regulatory bodies and law enforcement agencies. The presence and prevalence of substandard and counterfeit Artemisinin-based Combination Therapies need to be determined on open markets in Ghana; a review of the current policy; identifying any gaps and making recommendations on actions to be taken in addressing gaps identified are essential as the data provided and recommendations made will help in ensuring effective control of malaria in Ghana.

Methods

A field survey of antimalarial drugs was conducted in the central part of Ghana. The amount of active pharmaceutical ingredient in each Artemisinin-based Combination Therapy sample identified in the survey was measured using high performance liquid chromatographic analyses. Active pharmaceutical ingredient within the range of 85–115 % was considered as standard and active pharmaceutical ingredient results out of the range were considered as substandard. All samples were screened to confirm stated active pharmaceutical ingredient presence using mass spectrometry.

Results

A total of 256 Artemisinin-based Combination Therapies were purchased from known medicine outlets, including market stalls, hospitals/clinics, pharmacies, drug stores. Artemether lumefantrine (52.5 %) and artesunate amodiaquine (43.2 %) were the predominant Artemisinin-based Combination Therapies purchased. Of the 256 Artemisinin-based Combination Therapies purchased, 254 were tested, excluding two samples of Artesunate-SP. About 35 % of Artemisinin-based Combination Therapies were found to be substandard. Nine percent of Artemisinin-based Combination Therapies purchased were past their expiry date; no counterfeit (falsified) medicine samples were detected by either high performance liquid chromatographic or mass spectrometry.

Conclusion

A high proportion of Artemisinin-based Combination Therapies sold in central Ghana were found to be substandard. Manufacturing of medicines that do not adhere to good manufacturing practices may have contributed to the poor quality of the Artemisinin-based Combination Therapies procured. A strict law enforcement and quality monitoring systems is recommended to ensure effective malaria case management as part of malaria control.

Comparison of clustering pipelines for the analysis of mass spectrometry imaging data

Mass spectrometry imaging (MSI) is valuable for biomedical applications because it links molecular and morphological information. However, MSI datasets can be very large, and analyzing them to identify important biological patterns is a challenging computational problem. Many types of unsupervised analysis have been applied to MSI data, and in particular, clustering has recently gained attention for this application. In this paper, we present an exploratory study of the performance of different analysis pipelines using k-means and fuzzy k-means clustering. The results indicate the effects of different pre-processing and parameter selections on identifying biologically relevant patterns in MSI data.

Abstract AS05: Metabolomic signatures in sera from early stage ovarian cancer patients

PURPOSE: Lack of symptoms as well as the deficiency of highly specific biomarkers has resulted in only a quarter of ovarian cancer cases being diagnosed in stage I. Early detection combined with conventional therapies has resulted in 5-year survival rates up to 90%, while 5-year overall survival is less than 30% for women with advanced stage ovarian cancer. An effective screening strategy for early diagnosis would be particularly advantageous for ovarian cancer patients. Investigation into characteristic metabolomic patterns for disease has the potential to detect changes in cells, tissues, and biofluids that can aid in diagnosis at an early stage.

METHODS: Serum samples were collected from early-stage serous papillary or endometrioid ovarian cancer (n=26) and normal patients (n=40) and analyzed using ultra high performance liquid chromatography coupled with high resolution mass spectrometry (UPLC-MS) and tandem mass spectrometry (MS/MS). Metabolites were extracted from blood serum by precipitating proteins with methanol, lyophilization, and solvent reconstitution prior to MS analysis in both positive and negative electrospray ionization modes. Metabolic features were extracted with MZmine software. Untargeted multivariate statistical analysis employing support vector machine (SVM) learning methods, genetic algorithms and recursive feature elimination (RFE) selected a panel of metabolites that differentiates between the age-matched samples with better than 92% sensitivity and 91% specificity in all cases tested.

RESULTS: Comparison of metabolic phenotypes of ovarian cancer with normal metabolic signatures revealed unique metabolite patterns for ovarian cancer. From multivariate statistical analysis, panels consisting of 17-35 metabolic features from serum samples were found to differentiate between early stage cancer and normal with very high accuracy, sensitivity, and specificity.

CONCLUSIONS: Poor early diagnosis complicates collection of large patient cohorts for more detailed studies. Our preliminary work demonstrated that metabolites in serum samples may be useful for detecting early-stage ovarian cancer and support conducting larger, more focused studies.

(Grant support: Marsha Rivkin Ovarian Cancer Challenge Grant; Ovarian Cancer Research Fund (OCRF))

Citation Format: David A. Gaul, Christina M. Jones, Maria Eugenia Monge, Long Q. Tran, Martin M. Matzuk, John F. McDonald*, Facundo M. Fernandez*. Metabolomic signatures in sera from early stage ovarian cancer patients [abstract]. In: Proceedings of the 10th Biennial Ovarian Cancer Research Symposium; Sep 8-9, 2014; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(16 Suppl):Abstract nr AS05.

Responding to the pandemic of falsified medicines

Over the past decade, the number of countries reporting falsified (fake, spurious/falsely labeled/counterfeit) medicines and the types and quantities of fraudulent drugs being distributed have increased greatly. The obstacles in combatting falsified pharmaceuticals include 1) lack of consensus on definitions, 2) paucity of reliable and scalable technology to detect fakes before they reach patients, 3) poor global and national leadership and accountability systems for combating this scourge, and 4) deficient manufacturing and regulatory challenges, especially in China and India where fake products often originate. The major needs to improve the quality of the world's medicines fall into three main areas: 1) research to develop and compare accurate and affordable tools to identify high-quality drugs at all levels of distribution; 2) an international convention and national legislation to facilitate production and utilization of high-quality drugs and protect all countries from the criminal and the negligent who make, distribute, and sell life-threatening products; and 3) a highly qualified, well-supported international science and public health organization that will establish standards, drug-quality surveillance, and training programs like the U.S. Food and Drug Administration. Such leadership would give authoritative guidance for countries in cooperation with national medical regulatory agencies, pharmaceutical companies, and international agencies, all of which have an urgent interest and investment in ensuring that patients throughout the world have access to good quality medicines. The organization would also advocate strongly for including targets for achieving good quality medicines in the United Nations Millennium Development Goals and Sustainable Development Goals.

Quality of antimalarials at the epicenter of antimalarial drug resistance: results from an overt and mystery client survey in Cambodia

Widespread availability of monotherapies and falsified antimalarials is thought to have contributed to the historical development of multidrug-resistant malaria in Cambodia. This study aimed to document the quality of artemisinin-containing antimalarials (ACAs) and to compare two methods of collecting antimalarials from drug outlets: through open surveyors and mystery clients (MCs). Few oral artemisinin-based monotherapies and no suspected falsified medicines were found. All 291 samples contained the stated active pharmaceutical ingredient (API) of which 69% were considered good quality by chemical analysis. Overall, medicine quality did not differ by collection method, although open surveyors were less likely to obtain oral artemisinin-based monotherapies than MCs. The results are an encouraging indication of the positive impact of the country's efforts to tackle falsified antimalarials and artemisinin-based monotherapies. However, poor-quality medicines remain an ongoing challenge that demands sustained political will and investment of human and financial resources.

Seaweed allelopathy against coral: surface distribution of a seaweed secondary metabolite by imaging mass spectrometry

Coral reefs are in global decline, with seaweeds increasing as corals decrease. Although seaweeds inhibit coral growth, recruitment, and survivorship, the mechanism of these interactions is poorly understood. Here, we used field experiments to show that contact with four common seaweeds induces bleaching on natural colonies of Porites rus. Controls in contact with inert, plastic mimics of seaweeds did not bleach, suggesting seaweed effects resulted from allelopathy rather than shading, abrasion, or physical contact. Bioassay-guided fractionation of the hydrophobic extract from the red alga Phacelocarpus neurymenioides revealed a previously characterized antibacterial metabolite, neurymenolide A, as the main allelopathic agent. For allelopathy of lipid-soluble metabolites to be effective, the compounds would need to be deployed on algal surfaces where they could transfer to corals on contact. We used desorption electrospray ionization mass spectrometry (DESI-MS) to visualize and quantify neurymenolide A on the surface of P. neurymenioides, and we found the molecule on all surfaces analyzed, with highest concentrations on basal portions of blades.

Poor quality drugs: grand challenges in high throughput detection, countrywide sampling, and forensics in developing countries

Throughout history, poor quality medicines have been a persistent problem, with periodical crises in the supply of antimicrobials, such as fake cinchona bark in the 1600s and fake quinine in the 1800s. Regrettably, this problem seems to have grown in the last decade, especially afflicting unsuspecting patients and those seeking medicines via on-line pharmacies. Here we discuss some of the challenges related to the fight against poor quality drugs, and counterfeits in particular, with an emphasis on the analytical tools available, their relative performance, and the necessary workflows needed for distinguishing between genuine, substandard, degraded and counterfeit medicines.

Deblurring molecular images using desorption electrospray ionization mass spectrometry

Traditional imaging techniques for studying the spatial distribution of biological molecules such as proteins, metabolites, and lipids, require the a priori selection of a handful of target molecules. Imaging mass spectrometry provides a means to analyze thousands of molecules at a time within a tissue sample, adding spatial detail to proteomic, metabolomic, and lipidomic studies. Compared to traditional microscopic images, mass spectrometric images have reduced spatial resolution and require a destructive acquisition process. In order to increase spatial detail, we propose a constrained acquisition path and signal degradation model enabling the use of a general image deblurring algorithm. Our analysis shows the potential of this approach and supports prior observations that the effect of the sprayer focuses on a central region much smaller than the extent of the spray.

Assessment of hand-held Raman instrumentation for in situ screening for potentially counterfeit artesunate antimalarial tablets by FT-Raman spectroscopy and direct ionization mass spectrometry

Pharmaceutical counterfeiting has become a significant public health problem worldwide and new, rapid, user-friendly, reliable and inexpensive methods for drug quality screening are needed. This work illustrates the chemical characterization of genuine and fake artesunate antimalarial tablets by portable Raman spectroscopy and validation by FT-Raman spectroscopy and ambient mass spectrometry. The applicability of a compact and robust portable Raman spectrometer (TruScan) for the in situ chemical identification of counterfeit tablets is reported.

Serum biomarker profiling by solid-phase extraction with particle-embedded micro tips and matrix-assisted laser desorption/ionization mass spectrometry

One of the main challenges in high-throughput serum profiling by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is the development of proteome fractionation approaches that allow the acquisition of reproducible profiles with a maximum number of spectral features and minimum interferences from biological matrices. This study evaluates a new class of solid-phase extraction (SPE) pipette tips embedded with different chromatographic media for fractionation of model protein digests and serum samples. The materials embedded include strong anion exchange (SAX), weak cation exchange (WCX), C18, C8, C4, immobilized metal affinity chromatography (IMAC) and zirconium dioxide particles. Simple and rapid serum proteome profiling protocols based on these SPE micro tips are described and tested using a variety of MALDI matrices. We show that different types of particle-embedded SPE micro tips provide complementary information in terms of the spectral features detected for beta-casein digests and control human serum samples. The effect of different sample pretreatments, such as serum dilution and ultrafiltration using molecular weight cut-off membranes, and the reproducibility observed for replicate experiments, are also evaluated. The results demonstrate the usefulness of these simple SPE tips combined with offline MALDI-TOF MS for obtaining information-rich serum profiles, resulting in a robust, versatile and reproducible open-source platform for serum biomarker discovery.

Performance, Resolving Power, and Radial Ion Distributions of a Prototype Nanoelectrospray Ionization Resistive Glass Atmospheric Pressure Ion Mobility Spectrometer

In this article, we describe and characterize a novel ion mobility spectrometer constructed with monolithic resistive glass desolvation and drift regions. This instrument is equipped with switchable corona discharge and nanoelectrospray ionization sources and a Faraday plate detector. Following description of the instrument, pulsing electronics, and data acquisition system, we examine the effects of drift gas flow rate and temperature, and of the aperture grid to anode distance on the observed resolving power and sensitivity. Once optimum experimental parameters are identified, different ion gate pulse lengths, and their effect on the temporal spread of the ion packet were investigated. Resolving power ranged from an average value of 50 ms/ms for a 400-micros ion gate pulse, up to an average value of 68 ms/ms for a 100-micros ion gate pulse, and a 26-cm drift tube operated at 383 V cm(-1). Following these experiments, the radial distribution of ions in the drift region of the spectrometer was studied by using anodes of varying sizes, showing that the highest ionic density was located at the center of the drift tube. Finally, we demonstrate the applicability of this instrument to the study of small molecules of environmental relevance by analyzing a commercially available siderophore, deferoxamine mesylate, in both the free ligand and Fe-bound forms. Ion mobility experiments showed a dramatic shift to shorter drift times caused by conformational changes upon metal binding, in agreement with previous reversed-phase liquid chromatography observations.

High-sensitivity detection of biological amines using fast Hadamard transform CE coupled with photolytic optical gating

Here, we report the first utilization of Hadamard transform CE (HTCE), a high-sensitivity, multiplexed CE technique, with photolytic optical gating sample injection of caged fluorescent labels for the detection of biologically important amines. Previous implementations of HTCE have relied upon photobleaching optical gating sample injection of fluorescent dyes. Photolysis of caged fluorescent labels reduces the fluorescence background, providing marked enhancements in sensitivity compared to photobleaching. Application of fast Hadamard transform CE (fHTCE) for fluorescein-based dyes yields a ten-fold higher sensitivity for photolytic injections compared to photobleaching injections, due primarily to the reduced fluorescent background provided by caged fluorescent dyes. Detection limits as low as 5 pM (ca. 18 molecules per injection event) were obtained with on-column LIF detection using fHTCE in less than 25 s, with the capacity for continuous, online separations. Detection limits for glutamate and aspartate below 150 pM (1-2 amol/injection event) were obtained using photolytic sample injection, with separation efficiencies exceeding 1 x 10(6) plates/m and total multiplexed separation times as low as 8 s. These results strongly support the feasibility of this approach for high-sensitivity dynamic chemical monitoring applications.

Strain and phase identification of the U.S. category B agent Coxiella burnetii by matrix assisted laser desorption/ionization time-of-flight mass spectrometry and multivariate pattern recognition

Accurate bacterial identification is important in diagnosing disease and in microbial forensics. Coxiella burnetii, a highly infective microorganism causative of the human disease Q fever, is now considered a U.S. category B potential bioterrorism agent. We report here an approach for the confirmatory identification of C. burnetii at the strain level which involves the combined use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and supervised pattern recognition via Partial Least Squares-Discriminant Analysis (PLS-DA). C. burnetii isolates investigated in this study included the following prototype strains from different geographical and/or historical origins and with different antigenic properties: Nine Mile I, Australian QD, M44, KAV, PAV, Henzerling, and Ohio. After culture and purification following standard protocols, linear MALDI-TOF mass spectra of pure bacterial cultures were acquired in positive ion mode. Mass spectral data were normalized, baseline-corrected, denoised, binarized and modeled by PLS-DA under crossvalidation conditions. Robustness with respect to uncontrolled variations in the sample preparation and MALDI analysis protocol was assessed by repeating the experiment on five different days spanning a period of 6 months. The method was validated by the prediction of unknown C. burnetii samples in an independent test set with 100% sensitivity and specificity for five out of six strain classes.

Combined Fourier-transform infrared imaging and desorption electrospray-ionization linear ion-trap mass spectrometry for analysis of counterfeit antimalarial tablets

This paper reports use of a combination of Fourier-transform infrared (FTIR) spectroscopic imaging and desorption electrospray ionization linear ion-trap mass spectrometry (DESI MS) for characterization of counterfeit pharmaceutical tablets. The counterfeit artesunate antimalarial tablets were analyzed by both techniques. The results obtained revealed the ability of FTIR imaging in non-destructive micro-attenuated total reflection (ATR) mode to detect the distribution of all components in the tablet, the identities of which were confirmed by DESI MS. Chemical images of the tablets were obtained with high spatial resolution. The FTIR spectroscopic imaging method affords inherent chemical specificity with rapid acquisition of data. DESI MS enables high-sensitivity detection of trace organic compounds. Combination of these two orthogonal surface-characterization methods has great potential for detection and analysis of counterfeit tablets in the open air and without sample preparation.

Ambient generation of fatty acid methyl ester ions from bacterial whole cells by direct analysis in real time (DART) mass spectrometry

Direct analysis in real time (DART) is implemented on a time-of-flight (TOF) mass spectrometer, and used for the generation of fatty acid methyl esters (FAMEs) ions from whole bacterial cells.

Characterization of counterfeit artesunate antimalarial tablets from southeast Asia

In southeast Asia, the widespread high prevalence of counterfeits tablets of the vital antimalarial artesunate is of great public health concern. To assess the seriousness of this problem, we quantified the amount of active ingredient present in artesunate tablets by liquid chromatography coupled to mass spectrometry. This method, in conjunction with analysis of the packaging, classified tablets as genuine, substandard, or fake and validated results of the colorimetric Fast Red TR test. Eight (35%) of 23 fake artesunate samples contained the wrong active ingredients, which were identified as different erythromycins and paracetamol. Raman spectroscopy identified calcium carbonate as an excipient in 9 (39%) of 23 fake samples. Multivariate unsupervised pattern recognition results indicated two major clusters of artesunate counterfeits, those with counterfeit foil stickers and containing calcium carbonate, erythromycin, and paracetamol, and those with counterfeit holograms and containing starch but without evidence of erythromycin or paracetamol.

Protein identification via surface-induced dissociation in an FT-ICR mass spectrometer and a patchwork sequencing approach

Surface-induced dissociation (SID) and collision-induced dissociation (CID) are ion activation techniques based on energetic collisions with a surface or gas molecule, respectively. One noticeable difference between CID and SID is that SID does not require a collision gas for ion activation and is, therefore, directly compatible with the high vacuum requirement of Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometers. Eliminating the introduction of collision gas into the ICR cell for collisional activation dramatically shortens the acquisition time for MS/MS experiments, suggesting that SID could be utilized for high-throughput MS/MS studies in FT-ICR MS. We demonstrate for the first time the utility of SID combined with FT-ICR MS for protein identification. Tryptic digests of standard proteins were analyzed using a hybrid 6-tesla FT-ICR mass spectrometer with SID and CID capabilities. SID spectra of mass-selected singly and doubly charged peptides were obtained using a diamond-coated target mounted at the rear trapping plate of the ICR cell. The broad internal energy distribution deposited into the precursor ion following collision with the diamond surface allowed a variety of fragmentation channels to be accessed by SID. Composition and sequence qualifiers produced by SID of tryptic peptides were used to improve the statistical significance of database searches. Protein identification MASCOT scores obtained using SID were comparable or better than scores obtained using sustained off-resonance irradiation collision-induced dissociation (SORI-CID), the conventional ion activation technique in FT-ICR MS.

Fast Hadamard Transform Capillary Electrophoresis for On-Line, Time-Resolved Chemical Monitoring

We report a new approach for collecting and deconvoluting the data in Hadamard transform capillary electrophoresis, referred to as fast Hadamard transform capillary electrophoresis (fHTCE). Using fHTCE, total analysis times can be reduced by up to 48% per multiplexed separation compared to conventional Hadamard transform capillary electrophoresis (cHTCE) while providing comparable signal-to-noise ratio enhancements. In fHTCE, the sample is injected following a pseudorandom pulsing sequence derived from the first row of a simplex matrix (S-matrix) in contrast to cHTCE, which utilizes a sequence of twice the length. In addition to the temporal savings provided by fHTCE, a 50% reduction in sample consumption is also realized due to the decreased number of sample injections. We have applied fHTCE to the analysis of mixtures of neurotransmitters and related compounds to yield improved signal-to-noise ratios with a total analysis time under 10 s. In addition, we demonstrate the capability of fHTCE to perform time-resolved monitoring of changes in the concentration of model neurochemical compounds.

Direct high-resolution peptide and protein analysis by desorption electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

We report the first coupling of a desorption electrospray ionization (DESI) ion source to Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS) for high-resolution protein analysis. The DESI FT-ICR-MS source design is described in detail along with preliminary data obtained on peptides and proteins ranging from 1 to 5.7 kDa.

Passive protection to bovine rotavirus (BRV) infection induced by a BRV VP8* produced in plants using a TMV-based vector

We have previously reported on the use of a tobacco mosaic virus (TMV) vector TMV-30B to express foreign viral antigens for use as experimental immunogens. Here we describe the development of an improved TMV-30B vector that adds a sequence of 7 histidine residues to the C-terminus of recombinant proteins expressed in the vector. We used this TMV-30B-HISc vector to express the VP8* fragment of the VP4 protein from bovine rotavirus (BRV) strain C-486 in plants. Recombinant VP8* protein was purified from N. benthamiana leaves at 7 days post-inoculation by immobilized metal affinity chromatography. The plant-produced VP8* was initially detected using anti-His tag mAb and its antigenic nature was confirmed using both monoclonal and polyclonal specific antisera directed against BRV. Adult female mice, inoculated by the intraperinoteal route with an immunogen containing 4 microg of recombinant VP8*, developed a specific and sustained response to the native VP8* from the homologous BRV. Eighty five percent of suckling mice from immunized dams that were challenged with the homologous virus at the fifth day of age were protected from virus as compared to 35% of the pups from mothers immunized with a control protein. These results demonstrate that the plant-produced VP8* was able to induce passive protection in the new born through the immunization of dams. This suggests that the technology presented here provides a simple method for using plants as an inexpensive alternative source for production of recombinant anti-rotavirus antigens.

Domestic violence: effect on pregnancy outcome

A predominantly white, suburban, indigent population of pregnancy women were followed up to determine the incidence of domestic violence and its effect on preterm delivery, low birth weight, and outcome of pregnancy (infant admission to the neonatal intensive care unit. A total of 489 gravidas were screened for domestic violence and drug and alcohol abuse. Patients were assigned to the control group if they had no substance abuse and no domestic violence and to the study group if they had no substance abuse but were victims of domestic violence. Of the total study population, 20% were victims of domestic violence. Among patients suffering domestic violence, 22% had preterm deliveries as compared with 9% of patients without domestic violence (P = .002). Sixteen percent of patients in the study group had low-birth-weight babies compared with 6% of women in the control group (P = .002). No significant relationship was found between domestic violence and admission to the neonatal intensive care unit. Therefore, domestic violence is a risk factor for preterm delivery and low-birth-weight infants.

Passive immunity to bovine rotavirus in newborn calves fed colostrum supplements from cows immunized with recombinant SA11 rotavirus core-like particle (CLP) or virus-like particle (VLP) vaccines

Heterotypic passive immunity to IND (P/5/G6) bovine rotavirus (BRV) was evaluated. Three groups of calves (n = 5 per group) were fed 1% pooled colostrum supplements (birth to 7 days of age) from BRV seropositive cows vaccinated with recombinant SA11(P/2/G3) rotavirus-like particles (VLPs), recombinant SA11 rotavirus core-like particles (CLPs), or inactivated SA11 rotavirus (SA11). Control calves (n = 5 per group) received either pooled colostrum from unvaccinated (BRV field exposure seropositive) control cows, or no colostrum. IgG1 antibody titers to IND BRV for the pooled colostrum were: 1,048,576 (VLP); 1,048,576 (CLP); 262,144 (SA11); and 16,384 (control colostrum). Elevated titers of BRV neutralizing (VN) antibodies were present in VLP colostrum (98,000), and SA11 colostrum (25,000), but not in CLP colostrum (1400), compared to colostrum from nonvaccinates (2081). Calves were orally inoculated with virulent IND BRV at 2 days of age and challenged at post-inoculation day (PID) 21. Calves were monitored daily for diarrhea and faecal BRV shedding through PID 10 and post-challenge day (PCD) 10. After colostrum feeding, the IgG1 antibody titers were highest in serum and faeces of calves fed VLP and CLP colostrum, but VN and IgA antibodies were highest in calves fed VLP colostrum. After BRV inoculation, calves fed colostrum from vaccinated cows had significantly fewer days of BRV-associated diarrhea and BRV shedding than control calves. All calves fed VLP colostrum were protected from diarrhea after BRV inoculation; two calves shed BRV. In the CLP colostrum group, one calf developed BRV-associated diarrhea and all calves shed virus. In the SA11 colostrum group, three calves developed BRV-associated diarrhea and four calves shed virus. BRV-associated diarrhea and shedding occurred in 9 of 10 control calves. Active IgM antibody responses occurred in faeces and/or serum of most calves after BRV inoculation. However, the highest active antibody responses (IgM and IgG1 in serum, and IgM, IgG1 or IgA in faeces) after BRV inoculation were in calves fed control or no colostrum, in association with clinical diarrhea in most of these calves. After challenge at PID 21, BRV-associated diarrhea and shedding were of short duration or absent, in all groups. These results demonstrate the efficacy of colostrum from VLP vaccinated cows to provide heterologous, passive protection against BRV diarrhea and shedding in calves. In comparison, calves fed CLP or SA11 colostrum were only partially protected against BRV diarrhea or shedding.

Isotype-specific antibody responses to rotavirus and virus proteins in cows inoculated with subunit vaccines composed of recombinant SA11 rotavirus core-like particles (CLP) or virus-like particles (VLP)

The isotype antibody responses to bovine IND P5, G6 and simian SA11 P2, G3 rotavirus and SA11 rotavirus proteins (VP4, VP6 and VP7) in serum, colostrum and milk were analysed by ELISA in three groups of vaccinated cows and nonvaccinated controls. Pregnant cows were vaccinated intramuscularly and intramammarily with recombinant baculovirus-expressed SA11 rotavirus VLP (triple-layered virus-like particles containing rotavirus VP2, VP4, VP6 and VP7); CLP (double-layered core-like particles containing rotavirus VP2 and VP6); or inactivated SA11 rotavirus, respectively. Rotavirus antigen titers were highest (30-200-fold) in ELISA in the VLP vaccine compared to the inactivated SA11 vaccine. The IgG1, IgG2 and IgM geometric mean antibody titers (GMT) to rotavirus (titers to bovine rotavirus vs SA11 rotavirus did not differ significantly for any isotype or group) and the IgG2 GMT to VP6 in serum at calving in the vaccinated groups were significantly (P < 0.05) higher than in the control group. In colostrum, IgG1 and IgA rotavirus antibody titers were significantly elevated for VLP (IgG1 GMT 832225; IgA GMT 16384), CLP (IgG1 GMT 660561; IgA GMT 10321) and SA11 (IgG1 GMT 131072; IgA GMT 1448) vaccinated cows compared to control cows (IgG1 GMT 11585; IgA GMT 45). The IgG1 and IgA GMT to rotavirus were significantly elevated (6-100-fold) in milk of VLP and CLP vaccinated cows compared to SA11 vaccinated or control cows. The isotype antibody responses to VP6 in serum, colostrum and milk paralleled the responses to rotavirus, but titers were approximately 2-10-fold lower. Only cows vaccinated with VLP had significantly enhanced serum, colostral and milk antibody titers to rotavirus VP4 and VP7. These results demonstrate that rotavirus antibody titers in serum, colostrum and milk are significantly enhanced by use of non-infectious VLP, CLP and inactivated SA11 rotavirus vaccines, but the VLP or CLP vaccines induced the highest antibody responses, corresponding to their higher rotavirus antigen titers measured by ELISA.

Group A rotavirus veterinary vaccines

Group A rotaviruses cause diarrhea in young livestock and poultry; consequently, vaccination strategies have focused on induction of active or passive immunity. Gnotobiotic pigs and calves serve as useful models to evaluate induction of active immunity by candidate animal or human rotavirus vaccines. However, live attenuated rotavirus vaccines lacked efficacy when administered orally to calves and pigs in the field, presumably because colostral antibodies inhibited vaccine virus replication. The widespread occurrence of rotavirus antibodies in colostrum led to strategies for maternal rotavirus vaccination to boost lactogenic immunity and transfer passive antibodies to the neonate via colostrum and milk. The variable success of maternal rotavirus vaccines in the field is influenced by vaccine dose, strain, inactivating agent, adjuvant, route of administration, and environmental rotavirus exposure levels. The use of genetically engineered rotavirus-like particle vaccines in cows to boost antibodies in mammary secretions shows promise. Such subunit vaccines possess potential advantages over existing vaccines.

Recognition of B and T cell epitopes by cattle immunized with a synthetic peptide containing the major immunogenic site of VP1 FMDV 01 Campos

The precise location of B and T cell epitopes have been established in a peptide containing the major immunogenic site (residues 135-160) of FMDV strain 01 Campos (01C) VP1. The peptide (p135-160), administered free or conjugated to bovine serum albumin, induced complete protection in guinea pigs and a strong neutralizing antibody (NAb) response in cattle. Using a set of partially overlapping peptides it was shown that although several B cell epitopes were distributed along the p135-160, the residues responsible for the induction of NAb were restricted to the amino acids 135-144. In addition, bovines immunized with the p135-160 showed a strong proliferative response to this peptide but a very poor response against purified virus. Two T-epitopes were located in the 135-160 sequence: one on the region 135-144 and the other in the region 150-160. The immunodominance of these two T cell epitopes was confirmed in cattle immunized with inactivated virus vaccines.

Indirect immunofluorescence and immunodiffusion tests in the detection of antibodies to foot-and-mouth disease virus

The antibody response detected by indirect immunofluorescence (IIF) as well as that directed against 140 S and virus infection associated antigen (VIA), as detected by agar immunodiffusion, was studied in three mammal species susceptible to Foot and Mouth Disease Virus, after challenge with living virus, immunization and hyperimmunization with inactivated virus, and immunization followed by challenge. By spot indirect immunofluorescence, antibodies were detected only in animals undergoing an active infection, and were not detected in immunized or hyperimmunized animals. This behaviour was similar to that of the anti-VIA antibodies in the same groups of animals and differed from that of anti-140 S antibodies. It appeared that spot indirect immunofluorescence for the detection of VIA antigen is comparable to the immunodiffusion test, but the speed of IIF and the possibility of handling many samples make it more practical.