A5012716855- Advanced Chemical Sensor Technologies
- Analytical Chemistry and Chromatography
- Mass Spectrometry Techniques and Applications
- Metabolomics and Mass Spectrometry Studies
- Analytical chemistry methods development
- Spectroscopy and Laser Applications
- Air Quality and Health Impacts
- Catalytic Processes in Materials Science
- Gas Sensing Nanomaterials and Sensors
- Inhalation and Respiratory Drug Delivery
- Analytical Chemistry and Sensors
- Biochemical Analysis and Sensing Techniques
- Chronic Obstructive Pulmonary Disease (COPD) Research
- Olfactory and Sensory Function Studies
- Liver Disease and Transplantation
- Fatty Acid Research and Health
- Liver Disease Diagnosis and Treatment
- Chemical Thermodynamics and Molecular Structure
- Carcinogens and Genotoxicity Assessment
- Trace Elements in Health
- Heme Oxygenase-1 and Carbon Monoxide
- Toxic Organic Pollutants Impact
- Vitamin C and Antioxidants Research
- Asthma and respiratory diseases
- Nuclear Physics and Applications
Johns Hopkins University
2012-2024
Committee on Publication Ethics
2002
Environmental Molecular Sciences Laboratory
2001
Johns Hopkins Medicine
1991
Morgan State University
1988
Shanghai Medical College of Fudan University
1988
University of Baltimore
1988
Pennsylvania State University
1974-1981
Imperial College London
1969-1971
Detection and analysis of volatile compounds in exhaled breath represents an attractive tool for monitoring the metabolic status a patient disease diagnosis, since it is non-invasive fast. Numerous studies have already demonstrated benefit clinical settings/applications encouraged multidisciplinary research to reveal new insights regarding origins, pathways, pathophysiological roles components. Many methods are currently available help explore these directions, ranging from mass spectrometry...
State-of-the-art quantum- and interband-cascade-based chemical sensors may be effective new tools for the identification quantification of trace gases in human breath clinical uses. Increased or decreased concentrations these molecules are associated with pathogenesis a large number diseases. Current technologies enable analyses to performed on single results available real time. Critical parameters including sensor sensitivity, selectivity, real-time monitoring capability, robustness, cost,...
Volatile organic compounds (VOCs) in exhaled breath originate from current or previous environmental exposures (exogenous compounds) and internal metabolic (anabolic catabolic) production (endogenous compounds). The origins of certain VOCs presumed to be endogenous have been proposed useful as preclinical biomarkers various undiagnosed diseases including lung cancer, breast cardio-pulmonary disease. usual approach is develop difference algorithms comparing VOC profiles nominally healthy...
Background —Free radical–mediated oxidative damage to lipids is thought be an important process in the pathogenesis of atherosclerosis. Although previous studies have demonstrated a beneficial impact antioxidant vitamin supplements on lipid peroxidation, effect dietary patterns peroxidation unknown. Methods and Results —During 3-week run-in period randomized trial, 123 healthy individuals were fed control diet, low fruits, vegetables, dairy products, with 37% calories from fat. Participants...
A computerized system has been developed to monitor tidal volume, respiration rate, mouth pressure, and carbon dioxide during breath collection. This was used investigate variability in the production of biomarkers over an 8-h period. Hyperventilation occurred when collected from spontaneously breathing study subjects (n = 8). Therefore, samples were whose paced at a rate 10 breaths/min volumes gauged according body mass. In this "paced breathing" group 16), end-tidal concentrations isoprene...
Chronic liver disease is initially occult, has multiple aetiologies, involves complex diagnostic questions, and requires follow-up because progression likely. Blood tests biopsies are generally used, but have disadvantages. We developed a new test for based on abnormal concentrations of metabolic products detected in exhaled breath. This can be conjunction with other clinically accepted protocols, to detect classify chronic diseases. Samples breath collected from spontaneously breathing...
Background Cigarette smoke may promote atherogenesis by producing oxygen-derived free radicals that damage lipids. However, evidence in support of this hypothesis is inconsistent because most studies did not control for aspects diet (antioxidants and lipid substrate) confound the association between smoking measures peroxidation. Methods Results The relationships cigarette two peroxidation, breath ethane (an vivo assay) thiobarbituric acid–reactive substances (TBARS, an vitro assay), were...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTUltratrace Metals in Some Environmental and Biological SystemsJoseph J. Dulka Terence H. RisbyCite this: Anal. Chem. 1976, 48, 8, 640A–641APublication Date (Print):July 1, 1976Publication History Published online24 May 2012Published inissue 1 July 1976https://pubs.acs.org/doi/10.1021/ac50002a711https://doi.org/10.1021/ac50002a711research-articleACS PublicationsRequest reuse permissionsArticle Views51Altmetric-Citations42LEARN ABOUT THESE...
Breath analysis has the potential to detect and monitor diseases as well reduce corresponding medical costs while improving quality of a patient's life. Herein, portable prototype, consisting commercial breath sampler modified work platform for solid-state gas sensors was developed. The sensor is placed close mouth (<10 cm) minimizes mouth-to-sensor path avoid contamination dilution target marker. Additionally with an appropriate cooling concept, even high operating temperatures (e.g. 350...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemical characterization of organic adsorbates on diesel particulate matterJames A. Yergey, Terence H. Risby, and Samuel S. LestzCite this: Anal. Chem. 1982, 54, 3, 354–357Publication Date (Print):March 1, 1982Publication History Published online1 May 2002Published inissue 1 March 1982https://pubs.acs.org/doi/10.1021/ac00240a003https://doi.org/10.1021/ac00240a003research-articleACS PublicationsRequest reuse permissionsArticle...
Cavity-enhanced tunable diode laser absorption spectroscopy is an attractive method for measuring small concentrations of gaseous species. Ethane a breath biomarker lipid peroxidation initiated by reactive oxygen A noninvasive means quickly quantifying oxidative stress status has the potential broad clinical application. We present simple, compact system using off-axis integrated cavity output with interband cascade and demonstrate its use in real-time measurements ethane. detection...
A continuous wave, thermoelectrically cooled, distributed feedback quantum cascade laser (DFB-QCL) based sensor platform for the quantitative detection of ammonia (NH3) concentrations present in exhaled human breath is reported. The NH3 concentration measurements are performed with a 2f wavelength modulation quartz enhanced photoacoustic spectroscopy (QEPAS) technique, which very well suited real time analysis, due to fast gas exchange inside compact QEPAS cell. An air-cooled DFB-QCL was...
Particulate matter (PM) is a major by-product from the combustion of fossil fuels. The biological target inhaled PM pulmonary epithelium and resident macrophages. In this study, we demonstrate that cultured macrophages (RAW 264.7 cells) exposed continously to well-defined model [benzo[a]pyrene adsorbed on carbon black (CB+BaP)] exhibit time-dependent expression release cytokine tumor necrosis factor-alpha (TNF-alpha). CB+BaP also evoked programmed cell death or apoptosis in as assessed by...
Background/Aims: Both hemorrhagic and cardiogenic shock are associated with hepatic gene expression at resuscitation.This study investigated the potential role of intravascular superoxide anion as a proximal trigger heat protein expression.Methods: Preanesthetized pigs were subjected to 120 m total warm iscbemia.The survival model consisted warm, ischemia reperfusion (with activt~ portal-systemic bypass) followed by for 3 days.Serial biopsy samples evaluated 72 (HSP-72) messenger RNA (mRNA)...
Breath biomarkers have the potential to offer information that is similar conventional clinical tests or they are entirely unique. Preliminary data support use of breath in study liver disease, particular non-alcoholic fatty disease (NAFLD). It was evaluated whether ethanol, ethane, sulfur compounds and acetone would be associated with hepatic histopathology amongst morbidly obese patients presenting for bariatric surgery. samples were collected during a preoperative visit compared biopsies...