Jamil Khirbek Jamil Khirbek

Exhalomics as a noninvasive method for assessing rumen fermentationin dairy cows: Can exhaled-breath metabolomics replace rumen sampling?

M. Z. Islam, S. E. Räisänen, A. Schudel, K. Wang, T. He, C. Kunz, Y. Li, X. Ma, A. M. Serviento, Z. Zeng, F. Wahl, R. Zenobi, S. Giannoukos, and M. Niu.

Previously, we used secondary electrospray ionization-mass spectrometry (SESI-MS) to investigate the diurnal patterns and signal intensities of exhaled (EX) volatile fatty acids (VFA) of dairy cows. The current study aimed to validate the potential of an exhalomics approach for evaluating rumen fermentation. The experiment was conducted in a switchback design, with 3 periods of 9 d each, including 7 d for adaptation and 2 d for sampling. Four rumen-cannulated original Swiss Brown (Braunvieh) cows were randomly assigned to 1 of 2 diet sequences (ABA or BAB): (A) low starch (LS; 6.31% starch on a dry matter basis) and (B) high starch (HS; 16.2% starch on a dry matter basis). Feeding was once per day at 0830 h. Exhalome (with the GreenFeed System), and rumen samples were collected 8 times to represent every 3 h of a day, and EX-VFA and ruminal (RM)-VFA were analyzed using SESI-MS and HPLC, respectively. Furthermore, the VFA concentration in the gas phase (HR-VFA) was predicted based on RMVFA and Henry’s Law (HR) constants….

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Jamil Khirbek Jamil Khirbek

Preservation of exhaled breath samples for analysis by off-line SESI-HRMS: proof-of-concept study

Rosa A Sola-Martínez, Jiafa Zeng, Mo Awchi, Amanda Gisler, Kim Arnold, Kapil Dev Singh, Urs Frey, Manuel Cánovas Díaz, Teresa de Diego Puente, Pablo Sinues

Secondary electrospray ionization-high resolution mass spectrometry (SESI-HRMS) is an established technique in the field of breath analysis characterized by its short analysis time, as well as high levels of sensitivity and selectivity. Traditionally, SESI-HRMS has been used for real-time breath analysis, which requires subjects to be at the location of the analytical platform. Therefore, it limits the possibilities for an introduction of this methodology in day-to-day clinical practice. However, recent methodological developments have shown feasibility on the remote sampling of exhaled breath in Nalophan® bags prior to measurement using SESI-HRMS…

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Jamil Khirbek Jamil Khirbek

Prediction of systemic free and total valproic acid by off-line analysis of exhaled breath in epileptic children and adolescents

Mo Awchi, Kapil Dev Singh, Patricia E Dill, Urs Frey, Alexandre N Datta, and Pablo Sinues.

Therapeutic drug monitoring (TDM) of medications with a narrow therapeutic window is a common clinical practice to minimize toxic effects and maximize clinical outcomes. Routine analyses rely on the quantification of systemic blood concentrations of drugs. Alternative matrices such as exhaled breath are appealing because of their inherent non-invasive nature. This is especially the case for pediatric patients. We have recently

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Jamil Khirbek Jamil Khirbek

Data Collection of" Analysis of volatile short-chain fatty acids in the gas phase using secondary electrospray ionization coupled to mass spectrometry"

Cedric Wüthrich, Stamatios Giannoukos

The mass spectrometer used in this study was an Orbitrap Q-Exactive Plus (Thermo Scientific) operated with the manufacturer’s standard control software (ExactiveTune, version 2.9, Thermo Scientific) and Xcalibur (version 4.1. 31.9, Thermo Scientific). Mass calibration was done according to the instrument manual and was always more recent than seven days according to specifications.

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Jamil Khirbek Jamil Khirbek

Metabolic Insights Related to Sleep and Circadian Clocks from Mass Spectrometry-Based Analysis of Blood and Breath

Nora Kristina Nowak

Most physiological processes in humans are synchronized with their environment by socalled circadian clocks. These molecular time-keeping machineries are present in almost every cell. While light is the most important external stimulus to reset the circadian clocks, they can also be entrained by other stimuli, such as feeding or rest/activity cycles. Sleep is both, one of the major outputs of circadian clocks and also an independently regulated recuperative neurobiological process.

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Jamil Khirbek Jamil Khirbek

On-line Breath Metabolomics with Ambient High-Resolution Mass Spectrometry

Martin Thomas Gaugg

Respiratory diseases are among the leading causes of death worldwide and pose a great financial burden on the health care system. During the last decades the medical community has started to recognize that a patient’s individual set of genes, along with environmental factors, are immensely important for the diagnosis and treatment of diseases. This has led to a strong drive towards further developments in personalized and evidencebased medicine. Understanding the underlying metabolic fundamentals of diseases is crucial to provide the appropriate patient care.One of the fastest methods to obtain new insights in this regard is to analyze metabolites in exhaled breath, which offers a non-invasive window into human metabolism, and which can be monitored in real time.

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Jamil Khirbek Jamil Khirbek

Novel strategies for online detection of doping compounds in breath using secondary electrospray ionization mass spectrometry

Lukas Christian Meier

It has been known for years that breath analysis has the potential of becoming a powerful tool to acquire information on the health status of individuals. Using mass spectrometry (MS) for breath analysis would allow for the detection of hundreds of compounds simultaneously and even render real time (online) monitoring of the individual’s health status possible. Unfortunately, the efficient transfer of breath into mass spectrometers is difficult to achieve. Therefore, only very volatile organic compounds (VOCs) being present in breath at high concentrations have been measured so far. The work presented in this thesis intends to extend the range of compounds being detected in breath towards higher masses, less volatile and less concentrated compounds…

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