519 resultados para Exhaled breath


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Background: Monitoring alcohol use is important in numerous situations. Direct ethanol metabolites, such as ethyl glucuronide (EtG), have been shown to be useful tools in detecting alcohol use and documenting abstinence. For very frequent or continuous control of abstinence, they lack practicability. Therefore, devices measuring ethanol itself might be of interest. This pilot study aims at elucidating the usability and accuracy of the cellular photo digital breathalyzer (CPDB) compared to self-reports in a naturalistic setting. Method: 12 social drinkers were included. Subjects used a CPDB 4 times daily, kept diaries of alcohol use and submitted urine for EtG testing over a period of 5 weeks. Results: In total, the 12 subjects reported 84 drinking episodes. 1,609 breath tests were performed and 55 urine EtG tests were collected. Of 84 drinking episodes, CPDB detected 98.8%. The compliance rate for breath testing was 96%. Of the 55 EtG tests submitted, 1 (1.8%) was positive. Conclusions: The data suggest that the CPDB device holds promise in detecting high, moderate, and low alcohol intake. It seems to have advantages compared to biomarkers and other Monitoring devices. The preference for CPDB by the participants might explain the high compliance. Further studies including comparison with biomarkers and transdermal devices are needed.

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BACKGROUND The heart is subject to structural and functional changes with advancing age. However, the magnitude of cardiac age-dependent transformation has not been conclusively elucidated. METHODS This retrospective cardiac magnetic resonance (CMR) study included 183 subjects with normal structural and functional ventricular values. End systolic volume (ESV), end diastolic volume (EDV), and ejection fraction (EF) were obtained from the left and the right ventricle in breath-hold cine CMR. Patients were classified into four age groups (20-29, 30-49, 50-69, and ≥70 years) and cardiac measurements were compared using Pearson's rank correlation over the four different groups. RESULTS With advanced age a slight but significant decrease in ESV (r=-0.41 for both ventricles, P<0.001) and EDV (r=-0.39 for left ventricle, r=-0.35 for right ventricle, P<0.001) were observed associated with a significant increase in left (r=0.28, P<0.001) and right (r=0.27, P<0.01) ventricular EF reaching a maximal increase in EF of +8.4% (P<0.001) for the left and +6.1% (P<0.01) for the right ventricle in the oldest compared to the youngest patient group. Left ventricular myocardial mass significantly decreased over the four different age groups (P<0.05). CONCLUSIONS The aging process is associated with significant changes in left and right ventricular EF, ESV and EDV in subjects with no cardiac functional and structural abnormalities. These findings underline the importance of using age adapted values as standard of reference when evaluating CMR studies.

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AIM: To determine the feasibility of evaluating surgically induced hepatocyte damage using gadoxetate disodium (Gd-EOB-DTPA) as a marker for viable hepatocytes at magnetic resonance imaging (MRI) after liver resection. MATERIAL AND METHODS: Fifteen patients were prospectively enrolled in this institutional review board-approved study prior to elective liver resection after informed consent. Three Tesla MRI was performed 3-7 days after surgery. Three-dimensional (3D) T1-weighted (W) volumetric interpolated breath-hold gradient echo (VIBE) sequences covering the liver were acquired before and 20 min after Gd-EOB-DTPA administration. The signal-to-noise ratio (SNR) was used to compare the uptake of Gd-EOB-DTPA in healthy liver tissue and in liver tissue adjacent to the resection border applying paired Student's t-test. Correlations with potential influencing factors (blood loss, duration of intervention, age, pre-existing liver diseases, postoperative change of resection surface) were calculated using Pearson's correlation coefficient. RESULTS: Before Gd-EOB-DTPA administration the SNR did not differ significantly (p = 0.052) between healthy liver tissue adjacent to untouched liver borders [59.55 ± 25.46 (SD)] and the liver tissue compartment close to the resection surface (63.31 ± 27.24). During the hepatocyte-specific phase, the surgical site showed a significantly (p = 0.04) lower SNR (69.44 ± 24.23) compared to the healthy site (78.45 ± 27.71). Dynamic analyses revealed a significantly lower increase (p = 0.008) in signal intensity in the healthy tissue compared to the resection border compartment. CONCLUSION: EOB-DTPA-enhanced MRI may have the potential to be an effective non-invasive tool for detecting hepatocyte damage after liver resection.

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Purpose The sedimentation sign (SedSign) has been shown to discriminate well between selected patients with and without lumbar spinal stenosis (LSS). The purpose of this study was to compare the pressure values associated with LSS versus non-LSS and discuss whether a positive SedSign may be related to increased epidural pressure at the level of the stenosis. Methods We measured the intraoperative epidural pressure in five patients without LSS and a negative SedSign, and in five patients with LSS and a positive SedSign using a Codman TM catheter in prone position under radioscopy. Results Patients with a negative SedSign had a median epidural pressure of 9 mmHg independent of the measurement location. Breath and pulse-synchronous waves accounted for 1–3 mmHg. In patients with monosegmental LSS and a positive SedSign, the epidural pressure above and below the stenosis was similar (median 8–9 mmHg). At the level of the stenosis the median epidural pressure was 22 mmHg. A breath and pulse-synchronous wave was present cranial to the stenosis, but absent below. These findings were independent of the cross-sectional area of the spinal canal at the level of the stenosis. Conclusions Patients with LSS have an increased epidural pressure at the level of the stenosis and altered pressure wave characteristics below. We argue that the absence of sedimentation of lumbar nerve roots to the dorsal part of the dural sac in supine position may be due to tethering of affected nerve roots at the level of the stenosis.

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Compared with term-born infants, preterm infants have increased respiratory morbidity in the first year of life. We investigated whether lung function tests performed near term predict subsequent respiratory morbidity during the first year of life and compared this to standard clinical parameters in preterms.The prospective birth cohort included randomly selected preterm infants with and without bronchopulmonary dysplasia. Lung function (tidal breathing and multiple-breath washout) was measured at 44 weeks post-menstrual age during natural sleep. We assessed respiratory morbidity (wheeze, hospitalisation, inhalation and home oxygen therapy) after 1 year using a standardised questionnaire. We first assessed the association between lung function and subsequent respiratory morbidity. Secondly, we compared the predictive power of standard clinical predictors with and without lung function data.In 166 preterm infants, tidal volume, time to peak tidal expiratory flow/expiratory time ratio and respiratory rate were significantly associated with subsequent wheeze. In comparison with standard clinical predictors, lung function did not improve the prediction of later respiratory morbidity in an individual child.Although associated with later wheeze, noninvasive infant lung function shows large physiological variability and does not add to clinically relevant risk prediction for subsequent respiratory morbidity in an individual preterm.

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Over the last two decades, imaging of the aorta has undergone a clinically relevant change. As part of the change non-invasive imaging techniques have replaced invasive intra-arterial digital subtraction angiography as the former imaging gold standard for aortic diseases. Computed tomography (CT) and magnetic resonance imaging (MRI) constitute the backbone of pre- and postoperative aortic imaging because they allow for imaging of the entire aorta and its branches. The first part of this review article describes the imaging principles of CT and MRI with regard to aortic disease, shows how both technologies can be applied in every day clinical practice, offering exciting perspectives. Recent CT scanner generations deliver excellent image quality with a high spatial and temporal resolution. Technical developments have resulted in CT scan performed within a few seconds for the entire aorta. Therefore, CT angiography (CTA) is the imaging technology of choice for evaluating acute aortic syndromes, for diagnosis of most aortic pathologies, preoperative planning and postoperative follow-up after endovascular aortic repair. However, radiation dose and the risk of contrast induced nephropathy are major downsides of CTA. Optimisation of scan protocols and contrast media administration can help to reduce the required radiation dose and contrast media. MR angiography (MRA) is an excellent alternative to CTA for both diagnosis of aortic pathologies and postoperative follow-up. The lack of radiation is particularly beneficial for younger patients. A potential side effect of gadolinium contrast agents is nephrogenic systemic fibrosis (NSF). In patients with high risk of NSF unenhanced MRA can be performed with both ECG- and breath-gating techniques. Additionally, MRI provides the possibility to visualise and measure both dynamic and flow information.

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As Death of a Salesman opens, Willy Loman returns home “tired to the death” (p. 13). Lost in reveries about the beautiful countryside and the past, he's been driving off the road; and now he wants a cheese sandwich. But Linda's suggestion that he try a new American-type cheese — “It's whipped” (p. 16) — irritates Willy: “Why do you get American when I like Swiss?” (p. 17). His anger at being contradicted unleashes an indictment of modern industrialized America: The street is lined with cars. There's not a breath of fresh air in the neighborhood. The grass don't grow any more, you can't raise a carrot in the back yard. (p. 17). In the old days, “This time of year it was lilac and wisteria.” Now: “Smell the stink from that apartment house! And another one on the other side…” (pp. 17–18). But just as Willy defines the conflict between nature and industry, he pauses and simply wonders: “How can they whip cheese?” (p. 18). The clash between the old agrarian ideal and capitalistic enterprise is well documented in the literature on Death of a Salesman, as is the spiritual shift from Thomas Jefferson to Andrew Carnegie to Dale Carnegie that the play reflects. The son of a pioneer inventor and the slave to broken machines, Willy Loman seems to epitomize the victim of modern technology.

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The aim of this study was to test the effect of cardiac output (CO) and pulmonary artery hypertension (PHT) on volumetric capnography (VCap) derived-variables. Nine pigs were mechanically ventilated using fixed ventilatory settings. Two steps of PHT were induced by IV infusion of a thromboxane analogue: PHT25 [mean pulmonary arterial pressure (MPAP) of 25 mmHg] and PHT40 (MPAP of 40 mmHg). CO was increased by 50 % from baseline (COup) with an infusion of dobutamine ≥5 μg kg(-1) min(-1) and decreased by 40 % from baseline (COdown) infusing sodium nitroglycerine ≥30 μg kg(-1) min(-1) plus esmolol 500 μg kg(-1) min(-1). Another state of PHT and COdown was induced by severe hypoxemia (FiO2 0.07). Invasive hemodynamic data and VCap were recorded and compared before and after each step using a mixed random effects model. Compared to baseline, the normalized slope of phase III (SnIII) increased by 32 % in PHT25 and by 22 % in PHT40. SnIII decreased non-significantly by 4 % with COdown. A combination of PHT and COdown associated with severe hypoxemia increased SnIII by 28 % compared to baseline. The elimination of CO2 per breath decreased by 7 % in PHT40 and by 12 % in COdown but increased only slightly with COup. Dead space variables did not change significantly along the protocol. At constant ventilation and body metabolism, pulmonary artery hypertension and decreases in CO had the biggest effects on the SnIII of the volumetric capnogram and on the elimination of CO2.

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Clinical investigations on patients suffering from halitosis clearly reveal that in the vast majority of cases the source for an offensive breath odor can be found within the oral cavity (90%). Based on these studies, the main sources for intra-oral halitosis where tongue coating, gingivitis/periodontitis or a combination of the two. Thus, it is perfectly logical that general dental practitioners (GDPs) should be able to manage intra-oral halitosis under the conditions found in a normal dental practice. However, GDPs who are interested in diagnosing and treating halitosis are challenged to incorporate scientifically based strategies for use in their clinics. Therefore, the present paper summarizes the results of a consensus workshop of international authorities held with the aim to reach a consensus on general guidelines on how to assess and diagnose patients' breath odor concerns and general guidelines on regimens for the treatment of halitosis.

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PURPOSE Hodgkin lymphoma (HL) is a highly curable disease. Reducing late complications and second malignancies has become increasingly important. Radiotherapy target paradigms are currently changing and radiotherapy techniques are evolving rapidly. DESIGN This overview reports to what extent target volume reduction in involved-node (IN) and advanced radiotherapy techniques, such as intensity-modulated radiotherapy (IMRT) and proton therapy-compared with involved-field (IF) and 3D radiotherapy (3D-RT)- can reduce high doses to organs at risk (OAR) and examines the issues that still remain open. RESULTS Although no comparison of all available techniques on identical patient datasets exists, clear patterns emerge. Advanced dose-calculation algorithms (e.g., convolution-superposition/Monte Carlo) should be used in mediastinal HL. INRT consistently reduces treated volumes when compared with IFRT with the exact amount depending on the INRT definition. The number of patients that might significantly benefit from highly conformal techniques such as IMRT over 3D-RT regarding high-dose exposure to organs at risk (OAR) is smaller with INRT. The impact of larger volumes treated with low doses in advanced techniques is unclear. The type of IMRT used (static/rotational) is of minor importance. All advanced photon techniques result in similar potential benefits and disadvantages, therefore only the degree-of-modulation should be chosen based on individual treatment goals. Treatment in deep inspiration breath hold is being evaluated. Protons theoretically provide both excellent high-dose conformality and reduced integral dose. CONCLUSION Further reduction of treated volumes most effectively reduces OAR dose, most likely without disadvantages if the excellent control rates achieved currently are maintained. For both IFRT and INRT, the benefits of advanced radiotherapy techniques depend on the individual patient/target geometry. Their use should therefore be decided case by case with comparative treatment planning.

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BACKGROUND Multiple breath washout (MBW) derived Scond is an established index of ventilation inhomogeneity. Time-consuming post hoc calculations of the expirogram's slope of alveolar phase III (SIII) and the lack of available software hampered widespread application of Scond. METHODS Seventy-two school-aged children (45 with cystic fibrosis; CF) performed 3 nitrogen MBW. We tested a new automated algorithm for Scond analysis (Scondauto ) which comprised breath selection for SIII detection, calculation and reporting of test quality. We compared Scondauto to (i) standard Scond analysis (Scondmanual ) with manual breath selection and to (ii) pragmatic Scond analysis including all breaths (Scondall ). Primary outcomes were success rate and agreement between different Scond protocols, and Scond fitting quality (linear regression R(2) ). RESULTS Average Scondauto (0.06 for CF and 0.01 for controls) was not different from Scondmanual (0.06 for CF and 0.01 for controls) and showed comparable fitting quality (R(2) 0.53 for CF and 0.13 for controls vs. R(2) 0.54 for CF and 0.13 for controls). Scondall was similar in CF and controls but with inferior fitting quality compared to Scondauto and Scondmanual . CONCLUSIONS Automated Scond calculation is feasible and produces robust results comparable to the standard manual way of Scond calculation. This algorithm provides a valid, fast and objective tool for regular use, even in children. Pediatr Pulmonol. © 2014 Wiley Periodicals, Inc.

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An organoleptic assessment of an odor is defined as a method that can measure the strength of target odors and expresses the value in terms of a point or number with reference to a pre-defined organoleptic scale. Organoleptic assessments are performed using different scales and are used widely in industry (e.g. for measuring the effectiveness of anti-odor agents), in research (to discover relationships between bad breath and microbiology of the tongue, or the generation of particular volatile compounds), but it is also a prerequisite for the diagnosis of halitosis in individual patients required before directing appropriate treatment. An organoleptic assessment of halitosis patients may be carried out in specialized institutions but--based on the fact that in most cases the odor originates from oral structures--also by dental professionals including general dental practitioners (GDPs). Thus, this paper describes the scientific background for recommendations on how a GDP or dental hygienist or general practitioner with cases of bad breath should use organoleptic methods as a valid approach to assess malodor in patients, with a view to diagnosis and treatment, and subsequent treatment monitoring.

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AIMS: Testing for inducible myocardial ischaemia is one of the most important diagnostic procedures and has a strong impact on clinical decision-making. Current standard protocols are typically limited by the required infusion of vasodilatory substances. Recent data indicate that changes of myocardial oxygenation induced by hyperventilation and breath-holds can be monitored by oxygenation-sensitive (OS) cardiovascular magnetic resonance (CMR) and may be useful for assessing coronary vascular function. As tests using breathing manoeuvres may be safer, easier, and more comfortable than vasodilator stress agent infusion, we compared its impact on myocardial oxygenation with that of a standard adenosine infusion protocol. METHODS AND RESULTS: In 20 healthy volunteers, we assessed changes of myocardial oxygenation using OS-CMR at 3 T during adenosine infusion (140 µg/kg/min, i.v.) and during voluntary breathing manoeuvres: a maximal breath-hold following normal breathing and a maximal breath-hold following 60 s of hyperventilation. The study was successfully completed in 19 subjects. There was a significantly stronger myocardial response for hyperventilation (decrease of -10.6 ± 7.8%) and the following breath-hold (increase of 14.8 ± 6.6%) than adenosine (3.9 ± 6.5%), whereas a simple maximal voluntary breath-hold yielded a similar signal intensity increase (3.1 ± 3.9%). Subjective side effects occurred significantly more often with adenosine, especially in females. CONCLUSIONS: Hyperventilation combined with a subsequent long breath-hold and hyperventilation alone both have a greater impact on myocardial oxygenation changes than an intravenous administration of a standard dose of adenosine, as assessed by OS-CMR. Breathing manoeuvres may be more efficient, safer, and more comfortable than adenosine for the assessment of the coronary vasomotor response.

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The paper is a comparative inquiry into the roles of Ilia Chavchavadze (1837-1907) and Taras Shevchenko (1818-1861) as national poets and anti-colonial (anti-Tsarist) intellectuals within the context of their respective national traditions (Georgia and Ukraine). During the period of their activity (19th and the beginning of 20th century) both Ukraine and Georgia were under Tsarist imperial rule, albeit the two poets lived in different periods of Russian empire history. Through their major works, each called on their communities to ‘awaken’ and ‘revolt’ against oppression, rejected social apathy caused by Tsarist subjugation and raised awareness about the historical past of their nations. The non-acceptance of present and belief in an independent future was one of the dominant themes in the poetry and prose of both. Their contemporary importance is illustrated in political discourse both after Orange Revolution in Ukraine (2004), and Rose Revolution in Georgia (2003) where both poets are referred “as founding fathers of national ideology”, the history textbooks alluding to them as “symbols of anti-colonial resistance”. To this day, however, there has been surprisingly little academic writing in the West endeavoring to compare the works and activities of the two poets and their impact on national mobilization in Tsarist Ukraine and Georgia, even though their countries are often mentioned in a same breath by commentators on contemporary culture and politics. The paper attempts to fill this gap and tries to understand the relationship between literature and social mobilization in 19th century Russian Empire. By reflecting on Taras Shevchenko’s and Ilia Chavchavadze’s poetry, prose and social activism, I will try to explain how in different periods of Russian imperial history, the two poets helped to develop a modern form of political belonging among their compatriots and stimulated an anti-colonial mobilization with different political outcomes. To theorize on the role of poets and novelists in anti-colonial national movement, I will reflect on the writings of Benedict Anderson (1991), John Hutchinson (1994; 1999), Rory Finnin (2005; 2011) and problematize Miroslav Hroch’s (1996) three phase model of the development of national movements. Overall, the paper would aim to show the importance of, what John Hutchinson called, ‘cultural nationalists’ in understanding contemporary nationalist discourse in Georgian and Ukrainian societies.