In the last 30 days

• Open/close A new ¹³C breath test to detect vitamin B12 deficiency: a prevalent and poorly diagnosed health problem

  David A Wagner et al 2011 J. Breath Res. 5 046001 Tag this article

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  Vitamin B12 deficiency is emerging as a growing public health problem. The most commonly used diagnostic tests are limited in accuracy, sensitivity, and are non-specific for B12 deficiency. The aim of this study was to develop a simple B12 breath test (BBT) to more accurately evaluate vitamin B12 status as an alternative to the most common diagnostic test, serum B12 levels. The breath test is based on the metabolism of sodium 1- ¹³C-propionate to ¹³CO ₂ which requires B12 as a cofactor. We initially compared the BBT to current B12 diagnostic methods in 58 subjects. Subjects also received a second BBT 1–3 days after initial testing to evaluate reproducibility of results. Propionate dosage, fasting times, and collection periods were compared, respectively. The dose of sodium 1- ¹³C-propionate (10–50 mg) gave equivalent results while an 8 h fast was essential. Statistical analysis revealed that breath collection times could be reduced to just a baseline and 10 and 20 min following propionate dosing. We also measured the incidence of B12 deficiency with the BBT in 119 patients with chronic pancreatitis, Crohn's disease, small intestinal bacterial overgrowth, and subjects over 65 years of age. The BBT results agreed with previous publications showing a higher incidence of B12 deficiency in these patients. The BBT may provide clinicians with a non-invasive, accurate, reliable, and reproducible diagnostic test to detect vitamin B12 deficiency.

• Open/close Profile of eicosanoids in breath condensate in asthma and COPD

  Leandro Genehr Fritscher et al 2012 J. Breath Res. 6 026001 Tag this article

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  The collection of exhaled breath condensates (EBC) is a noninvasive method for obtaining samples from the lungs. Eicosanoids are lipid mediators implicated in the asthmatic inflammatory response. The objective of our study was to investigate whether the profile of eicosanoid lipid mediators in EBC can characterize the inflammation in asthma and chronic obstructive pulmonary disease (COPD). EBC samples were collected from 22 healthy controls (C), 25 mild intermittent asthmatics (MIA), 20 with moderate to severe asthma (MSA) and 20 with moderate to severe COPD. EBC samples were analyzed by unique tandem mass spectrometry that allows the quantification of up to 25 eicosanoid mediators simultaneously. No differences were found between MIA and C. Subjects with MSA and COPD had higher levels of 6-keto, PGE2, LTB4, 11–12 EET and AA, while lower levels of LXA4, 11DHyTxB2, 11HETE and 8,9EET, when compared to MSA and C ( p < 0.05). Our study shows that the analysis of EBC through mass spectrometry is mixed and has a similar response in MSA and COPD when compared to MIA and controls.

• Open/close LC-ESI-MS/MS method for oxidative stress multimarker screening in the exhaled breath condensate of asbestosis/silicosis patients

  K Syslová et al 2010 J. Breath Res. 4 017104 Tag this article

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  The sensitive assay method was developed for a parallel, rapid and precise determination of the most prominent oxidative stress biomarkers: 8- iso-prostaglandin F _2α a lipid oxidation biomarker, o-tyrosine an amino acid oxidation biomarker and 8-hydroxy-2'-deoxy-guanosine a nucleic acid oxidation biomarker. The method consisted of a pre-treatment part, freeze drying (lyophilization), serving the purpose of biomarkers concentration from the exhaled breath condensate and detection method LC-ESI-MS/MS, where the selected reaction-monitoring mode was used for its extremely high degree of selectivity and the stable-isotope-dilution assay for its high precision of quantification. The developed method is characterized by the following parameters: the precision was higher than 84.3% and the mean accuracy (relative error) was determined lower than 11.6%. The method was tested on samples obtained from patients diagnosed with asbestosis and silicosis, occupational diseases induced by oxidative stress, and then compared with samples from healthy subjects. The difference in biomarkers' concentration levels found between the two groups was statistically significant.

• Open/close A modeling-based evaluation of isothermal rebreathing for breath gas analyses of highly soluble volatile organic compounds

  J King et al 2012 J. Breath Res. 6 016005 Tag this article

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  Isothermal rebreathing has been proposed as an experimental technique for estimating the alveolar levels of hydrophilic volatile organic compounds (VOCs) in exhaled breath. Using the prototypic test compounds acetone and methanol, we demonstrate that the end-tidal breath profiles of such substances during isothermal rebreathing show a characteristic increase that contradicts the conventional pulmonary inert gas elimination theory due to Farhi. On the other hand, these profiles can reliably be captured by virtue of a previously developed mathematical model for the general exhalation kinetics of highly soluble, blood-borne VOCs, which explicitly takes into account airway gas exchange as a major determinant of the observable breath output. This model allows for a mechanistic analysis of various rebreathing protocols suggested in the literature. In particular, it predicts that the end-exhaled levels of acetone and methanol measured during free tidal breathing will underestimate the underlying alveolar concentration by a factor of up to 1.5. Moreover, it clarifies the discrepancies between in vitro and in vivo blood–breath ratios of hydrophilic VOCs and yields further quantitative insights into the physiological components of isothermal rebreathing and highly soluble gas exchange in general.

• Open/close Observing the human exposome as reflected in breath biomarkers: heat map data interpretation for environmental and intelligence research

  Joachim D Pleil et al 2011 J. Breath Res. 5 037104 Tag this article

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  Over the past decade, the research of human system biology and the interactions with the external environment has permeated all phases of environmental, medical and public health research. Similar to the fields of genomics and proteomics research, the advent of new instrumentation for measuring breath biomarkers and their associated meta-data also provide very useful, albeit complex, data structures. The biomarker research community is beginning to invoke tools from system biology to assess the impact of environmental exposures, as well as from internal health states, on the expression of suites of chemicals in exhaled breath. This new approach introduces the concept of the exposome as a complement to the genome in exploring the environment–gene interaction. In addition to answering questions regarding health status for the medical community, breath biomarker patterns are useful for assessing public health risks from environmental exposures. Furthermore, breath biomarker patterns can inform security risks from suspects via covert interrogation of blood borne chemical levels that reflect previous activities. This paper discusses how different classes of exhaled breath biomarker measurements can be used to rapidly assess patterns in complex data. We present exhaled breath data sets to demonstrate the value of the graphical 'heat map' approach for hypothesis development and subsequent guidance for stochastic and mixed effect data interpretation. We also show how to graphically interpret exhaled breath measurements of exogenous jet fuel components, as well as exhaled breath condensate measurements of endogenous chemicals.

• Open/close Volatile biomarkers in the breath of women with breast cancer

  Michael Phillips et al 2010 J. Breath Res. 4 026003 Tag this article

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  We sought biomarkers of breast cancer in the breath because the disease is accompanied by increased oxidative stress and induction of cytochrome P450 enzymes, both of which generate volatile organic compounds (VOCs) that are excreted in breath. We analyzed breath VOCs in 54 women with biopsy-proven breast cancer and 204 cancer-free controls, using gas chromatography/mass spectroscopy. Chromatograms were converted into a series of data points by segmenting them into 900 time slices (8 s duration, 4 s overlap) and determining their alveolar gradients (abundance in breath minus abundance in ambient room air). Monte Carlo simulations identified time slices with better than random accuracy as biomarkers of breast cancer by excluding random identifiers. Patients were randomly allocated to training sets or test sets in 2:1 data splits. In the training sets, time slices were ranked according their C-statistic values (area under curve of receiver operating characteristic), and the top ten time slices were combined in multivariate algorithms that were cross-validated in the test sets. Monte Carlo simulations identified an excess of correct over random time slices, consistent with non-random biomarkers of breast cancer in the breath. The outcomes of ten random data splits (mean (standard deviation)) in the training sets were sensitivity = 78.5% (6.14), specificity = 88.3% (5.47), C-statistic = 0.89 (0.03) and in the test sets, sensitivity = 75.3% (7.22), specificity = 84.8 (9.97), C-statistic = 0.83 (0.06). A breath test identified women with breast cancer, employing a combination of volatile biomarkers in a multivariate algorithm.

• Open/close Hydrogen sulfide increases hepatic differentiation in tooth-pulp stem cells

  Nikolay Ishkitiev et al 2012 J. Breath Res. 6 017103 Tag this article

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  The toxicity of hydrogen sulfide (H ₂S), an oral malodorous compound, is well reported. We have recently established an experimental model of hepatic differentiation from human tooth-pulp stem cells (HTPC) using serum-free medium. The objective of the present study is to determine the effect of H ₂S on hepatic differentiation. The CD117 positive cell fraction was obtained from deciduous HTPC using magnetic cell sorting. After 3–4 passages, cells were grown in Dulbecco's modified Eagle's medium supplemented with insulin-transferrin-selenium-x (ITS-x), embryotrophic factor (ETF) and hepatocyte growth factor (HGF) for hepatic commitment (five days). For hepatic differentiation the cells were cultured in Iscove's modified Dulbecco's medium supplemented with ITS-x, ETF, oncostatin, HGF and dexamethasone for 15 days in air containing 5% CO ₂, with or without H ₂S at 0.05 ng ml ⁻¹. Cells were assayed for the expression of hepatic markers α-fetoprotein, albumin or carbamoyl phosphate synthetase, and urea concentrations and glycogen synthesis were also determined. The panel of hepatic markers was expressed more in the test groups exposed to H ₂S than in the control groups. Urea and glycogen production were also increased, especially glycogen which was approximately five times greater compared to the control ( p < 0.01). We concluded that H ₂S at physiological concentrations increased the ability of HTPC to undergo hepatogenic differentiation.

• Open/close Advances in breath odor research: re-evaluation and newly-arising sciences

  Ken Yaegaki 2012 J. Breath Res. 6 010201 Tag this article

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  The articles in this special section describe the most recent advances in halitosis research presented at the Ninth International Conference on Breath Odor Research, a joint conference with the XXIV CONBRAPE (Brazilian Congress of Periodontology) held at Bahia Othon Palace Hotel in Salvador, Bahia, Brazil on 25–28 May 2011. It has been almost half a century since Joseph Tonzetich of the Faculty of Dentistry at the University of British Columbia, Vancouver, Canada (the first honorable member of the International Society for Breath Odor Research (ISBOR) who died in 2000, and is known as 'the godfather of halitosis research') published his first halitosis paper entitled 'Evaluation of volatile odoriferous components of saliva' in Archives of Oral Biology in 1964 [1]. This was the starting point for breath-odor research, long before ISBOR was established, although research in this area had declined by the time we convened global collaboration in halitosis research.

  One must ask the question; what progress have we made during the past half-century? Although a few bad-breath detectors have appeared on the market, organoleptic scoring is still likely to remain as the 'gold standard'. In the 21st century, people in modern dentistry or medicine are still sniffing their patients' breath in order to diagnose halitosis, a very subjective method! Halitosis is widely believed to be simple to diagnose and treat, but this is certainly not the case, considering we have not yet even completed an objective detection measurement protocol for oral malodor.

  In the treatment of halitosis, for many years before Tonzetich came into the field, tongue coating had been suspected to be the main cause, and this was scientifically proven a quarter of a century ago. However, people still visually and subjectively measure the amount of tongue coating to diagnose halitosis and an objective and more accurate method is required and needs to be developed. Those of us that work in this field employ mainly subjective protocols for diagnosis, but scientists are well aware that the data obtained by subjective procedures are not universal and therefore it is not possible to compare data obtained by a subjective measure with data from a different paper. It has been suggested that our procedures in halitosis clinics are not scientific and are almost the same as they were hundreds of years ago. Why have we not made progress in these fundamental measures for halitosis clinics? Everybody involved in halitosis clinics or the related sciences should ask themselves this question.

  Removing tongue coating (TC), which consists mostly of bacteria and exfoliated keratinized epithelial cells, is a radical remedy and is considered as the most effective way to treat halitosis. For many years, people employed mechanical tongue-cleaning methods, such as using a tongue scraper. In the early 1970s it was reported that mechanical stimulation promotes tongue cancer [2] . This hypothesis may not be absolutely correct, since most tongue cancers are found on the side (lateral margin) of middle third of the tongue, and so the relationship between tongue scraping and cancer has not yet been confirmed. However, there is still a possibility that mechanical stimulation is one of the causes of tongue cancer. To effectively and safely remove tongue coating there is no doubt that we must develop a novel technology without using mechanical stimulation, but no such research efforts have yet been reported since the early 1970s.

  The protocols for halitosis clinical research can be divided into two sub-classifications: short-term and long-term. For both groups, subjects must abstain from ingestion of food, drinking and oral hygiene for four hours prior to evaluation of oral malodor, as described in [3], since this is the best time to measure volatile sulfur compounds (VSCs), as defined by the ADA guidelines. A recent paper has suggested that this protocol might not be correct, since eating and oral hygiene may affect VSCs in mouth air for longer than four hours after these activities [4]. In long-term studies, three weeks' intervention is recommended by the ADA, during which time they measure malodor strength or VSC concentration at the baseline each day. The premise of this protocol is that the baseline of VSC concentration or malodor strength is constant over certain days, but there are those who doubt that the baseline is consistent.

  The organoleptic procedure is perceived as the gold standard for diagnosing oral malodor; however, for clinical work on halitosis, not only detection but also quantification is required. Organoleptic measurements do not require purpose-build apparatus, which explains why this has been a popular method among clinicians. But there are many drawbacks to this type of diagnosis. Quantification of odor sensations is very difficult, and the most difficult feature of the organoleptic procedures is stimulus presentation, while objective measurements directly determine the concentration of stimulus. Therefore, halitosis detectors should be the method of choice for clinicians.

  A number of halitosis detectors have been used in the past 30 years. The portable sulfide monitor was very popular, but it also reacts with other compounds which cannot be accurately detected. Recently, portable gas chromatographs (GCs) were introduced, but this exciting technology could only report a few evaluations. Even using portable or regular GCs, the ADA recommends that their protocols be employed in clinical research.

  The papers selected for this special section provide some answers to the above questions or demonstrate a novel aspect of halitosis pathology. Moreover, they illustrate the diversity of approaches to the pathological and physiological activities of VSCs. It is a challenging field.

  The main challenges, as noted by K Yeagaki et al [5], are that problems have been identified in current, widely-used protocols. (1) The baselines of VSC concentrations in mouth air varied considerably over the course of a week. (2) When subjects refrained from eating, drinking and oral hygiene, including mouth rinsing, the VSC concentrations remained constant until the subject began eating again. (3) Over a six-hour period after a meal and oral hygiene, VSC concentrations decreased significantly. The above data point to optimal times and conditions for sampling subjects. Yeagaki et al also compared measurements obtained using several portable devices with measurements obtained using GCs, showing that portable devices demonstrate capabilities similar to those of GCs. Thus, a recommended protocol has been established. The proposed protocol includes the following recommendations: (a) a short-term rather than long-term study is strongly recommended, since VSC concentrations are constant in the short term; (b) a crossover study would best avoid the effects of individual specificities on each clinical intervention; and (c) measurements of VSCs should preferably be carried out using either a GC or a portable GC.

  To control VSC production, removing the TC is essential for the maintenance of oral hygiene and tongue-brushing or a scraper is utilized for this purpose. Mechanical stimulation needs to be eliminated as much as possible for the reasons mentioned above or to avoid unpleasant side effects. Nohno et al [6] have developed candy tablets containing a protease, actinidine, and effect of long-term use of these on both TC accumulation and the concentration of VSCs in mouth air has been determined. This is a novel procedure that removes the TC safely. Although most researchers and clinicians evaluate TC accumulation subjectively and visually, this is neither scientific nor objective. Nohno et al have also demonstrated an objective method of evaluating TC using a digital camera and the software ImageJ (NIH, USA). Moreover, they suggest that a long-term research design might not be appropriate. To develop new halitosis sciences, ISBOR would never to nip new knowledge in the bud—we should nurture such a promising young bud.

  Tangerman et al [7] found no association between halitosis and H. pylori infection of the stomach, although H. pylori is believed to be a cause of extra-oral pathologic halitosis. Suzuki et al [8] found that the use of probiotics, a now popular way for controlling oral malodor, is effective in reducing TC accumulation, but they also described its limitations. Determining the limitations of a remedy is essential for both clinicians and patients. We must encourage the adoption of such a presentation style as demonstrated by Suzuki et al among breath-odor clinical scientists or clinicians.

  Possible chemosensory dysfunction can elicit halitosis complaints. Falc\~ao et al [9] found that chemosensory dysfunction may cause pseudo-halitosis that proves very difficult to treat.

  Aoyama et al [10] reviewed the role of p53 in the apoptosis of periodontal tissues caused by oral malodorous compounds, and emphasized its toxicity. This information could be very useful in enabling people to prevent halitosis. Ishkitiev et al [11] established the protocol for differentiation of human dental pulp stem cells to hepatic cells, and found that hydrogen sulfide increases hepatic differentiation. This is a positive effect of oral malodorous compounds. However, they still need to establish universally accepted standards for evaluating the toxicity or positive effects of VSCs as shown in their report, since those topics are not yet well understood among halitosis scientists.

  I would like to emphasise that this editorial represents only my own views on some of the most interesting findings in halitosis research. However, I must stress again that it is time to re-evaluate the halitosis clinical sciences, and to invest in the newly-arising sciences of halitosis. We look forward to our next ISBOR conference in two years' time.

  References

  [1] Tonzetich J and Richter V J 1964 Arch. Oral. Biol. 9 39–45

  [2] Yaegaki K, Coil J M, Kamemizu T, and Miyazaki H 2002 Int. Dent. J. 52 192–6

  [3] American Dental Association 2003 cceptance Program Guidelines: Products Used in the Management of Oral Malodor (Chicago, IL: American Dental Association) pp 1–14

  [4] Fukui Y, Yaegaki K, Murata T, Sato T, Tanaka T, Imai, T Kamoda T and Herai M 2008 nt. Dent. J. 58 159–66

  [5]Yaegaki K et al 2012 J. Breath Res. 6 017101

  [6] Nohno K, Yamaga T, Kaneko N and Miyazaki H 2012 J. Breath Res. 6 017107

  [7] Tangerman A, Winkel E G, de Laat L, van Oijen A H and de Boer W A 2012 J. Breath Res. 6 017102

  [8] Suzuki N, Tanabe K, Takeshita T, Yoneda M, Iwamoto T, Oshiro S, Yamashita Y and Hirofuji T 2012 J. Breath Res. 6 017106

  [9] Falcã o D P, Vieira C N and Batista de Amorim R F 2012 J. Breath Res. 6 017105

  [10] Aoyama I, Yaegaki K, Calenic B, Ii H, Ishkitiev N and Imai T 2012 J. Breath Res. 6 017104

  [11] Ishkitiev N, Calenic B, Aoyama I, Ii H, Yaegaki K and Imai T 2012 J. Breath Res. 6 017103

• Open/close Clinical study of multiple breath biomarkers of asthma and COPD (NO, CO₂, CO and N₂O) by infrared laser spectroscopy

  Joanne H Shorter et al 2011 J. Breath Res. 5 037108 Tag this article

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  Breath analysis is a powerful non-invasive technique for the diagnosis and monitoring of respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Exhaled nitric oxide (NO) and carbon monoxide (CO) are markers of airway inflammation and can indicate the extent of respiratory diseases. We have developed a compact fast response quantum cascade laser system for analysis of multiple gases by tunable infrared absorption spectroscopy. The ARI breath analysis instrument has been deployed in a study of exhaled breath from patients with asthma or COPD. A total of 173 subjects participated, including both adult and pediatric patients. Patients in asthma or COPD exacerbations were evaluated twice—during the exacerbation and at a follow-up visit—to compare variations in breath biomarkers during these events. The change in exhaled NO levels between exacerbation and 'well' visits is consistent with spirometry data collected. Respiratory models are important for understanding the exchange dynamics of nitric oxide and other species in the lungs and airways. At each patient's visit, tests were conducted at four expiratory flow rates. We have applied a trumpet model with axial diffusion to the multi-flow exhaled nitric oxide data, obtaining NO alveolar concentrations and airway fluxes. We found higher airway fluxes for those with more severe asthma and during exacerbation events. The alveolar concentrations from the model were higher in adults with asthma and COPD, but this trend was less clear among the pediatric subjects.

• Open/close Standardization of clinical protocols in oral malodor research

  Ken Yaegaki et al 2012 J. Breath Res. 6 017101 Tag this article

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  The objective of this study is to standardize protocols for clinical research into oral malodor caused by volatile sulfur compounds (VSCs). To detect VSCs, a gas chromatograph (GC) using a flame photometric detector equipped with a bandpass filter (at 393 nm) is the gold standard (sensitivity: 5 × 10 ⁻¹¹ gS s ⁻¹). The baselines of VSC concentrations in mouth air varied considerably over a week. When the subjects refrained from eating, drinking and oral hygiene including mouth rinsing, the VSC concentrations remained constant until eating. Over a 6 h period after a meal, VSC concentrations decreased dramatically ( p < 0.01). These results point to optimal times and conditions for sampling subjects. Several portable devices were compared with the measurements by the GCs. Portable GCs demonstrated capabilities similar to those of the GCs. We also applied the recommended protocols described below to clinical research testing the efficacy of ZnCl ₂ products, and confirmed that using the recommended protocols in a randomized crossover design would provide very clear results. Proposed protocols include: (a) a short-term study rather than a long-term study is strongly recommended, since the VSC concentrations are constant in the short term; (b) a crossover study would be the best design to avoid the effects of individual specificities on each clinical intervention; (c) measurements of VSCs should preferably be carried out using either a GC or portable GCs.