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[Display omitted] • The rod-like CaCl 2 @Cu NPs@MIL53(Al)–NH 2 was modified Au screen-printed electrodes. • Ionic liquids were used as electrolytes constructing a planar ammonia sensor. • A novel electrochemical platform for exhaled ammonia analysis was designed. • The prepared sensor has excellent resistance to high humidity and interference. Exhaled gas analysis is an effective and non-invasive method for disease diagnosis. However, due to the complexity of the exhaled gases, this is a challenge for most sensing devices. Herein, CaCl 2 -Cu NPs-MIL53(Al)–NH 2 composites modified with screen-printed electrodes (SPEs) and ionic liquids [BMIM][BF 4 ] were used as electrolytes to construct a novel electrochemical ammonia sensor. CaCl 2 -Cu NPs-MIL53(Al)–NH 2 /SPEs possessed excellent performance, exhibiting good linearity in the range of 0.5–500 ppm with a low limit of detection (0.25 ppm) and a fast response time for 10 ppm ammonia (5.4 s). Most importantly, CaCl 2 -Cu NPs-MIL53(Al)–NH 2 /SPEs showed excellent resistance to high humidity and interference, which is required for exhaled gas analysis. Furthermore, compared to standard spectrophotometry, this method also can provide satisfactory recovery (101.43–103.98 %), suggesting that this sensor is promising for the detection of exhaled gases in the future. [ABSTRACT FROM AUTHOR]

Due to various biochemical fractionation processes during lipid synthesis, the lipid molecules in the body contain substantially lower concentrations of 13 C than the nonlipid molecules. Because of the isotopic differences between these two endogenous nutrient pools, any shift toward nonlipid fuel oxidation would be expected to increase in the δ 13 C of the exhaled breath. Interestingly, the possibility of whether or not an exercise-induced change actually occurs has been debated in literature for over two decades and researchers have still not reached a consensus. We measured ventilatory and metabolic variables before, during, and after exercise in forty-eight adults (n = 25 females, n = 23 males; 20.1 ± 1.9 years) assigned to either a resting treatment or one of three exercising treatments where they maintained a heart rate of 130, 150, or 170 bpm for 56 min. We found that the mean metabolic rates of the exercising groups increased 4.4-fold, 6.1-fold, and 7.7-fold above resting values, respectively. Exercise caused small increases in respiratory exchange ratios (e.g., from 0.83 ± 0.08 to 0.86 ± 0.10) indicative of increased carbohydrate oxidation, but these changes were too variable to be reliably correlated with exercise intensity. In contrast, the δ 13 C of the exhaled breath increased by 0.62 ± 0.19‰, 1.14 ± 0.29‰, and 1.79 ± 0.50‰, respectively, for the three groups and was significantly correlated with the intensity of exercise. We also show that the isotopic difference of the lipid and nonlipids of the body is similar (~ 2.7‰) even when consuming bulk diets that are isotopically distinct (> 8‰). If not corrected for, these exercise-induced changes in δ 13 C of the breath would be sufficiently large to skew the results of studies investigating the oxidative fates of exogenous nutritional supplements. [ABSTRACT FROM AUTHOR]

Abstract: Many animals undergo extended periods of fasting. During these fasts, animals oxidize a ratio of macronutrients dependent on the nutritional, energetic, and hydric requirements of the fasting period. In this study, we use Japanese quail (Coturnix coturnix japonica), a bird with natural intermediate fasting periods, to examine macronutrient use during a 6d fast. We raised groups of quail on isotopically labeled materials (13C-1-leucine, 13C-U-glucose, or 13C-1-palmitic acid) with the intent of labeling specific macronutrient/tissue pools in each treatment, and then traced their use as fuels by measuring the δ13C values of breath CO2. Based on changes in δ13C values during the fast, it appears that the carbohydrate label,13C-U-glucose, was largely incorporated into the lipid pool and thus breath samples ultimately reflected lipid use rather than carbohydrate use. In the lipid treatment, the 13C-1-palmitic acid faithfully labeled the lipid pool and was reflected in the kinetics δ13C values in breath CO2 during the fast. Endogenous lipid oxidation peaked after 24h of fasting and remained constantly elevated thereafter. The protein label,13C-1-leucine, showed clear diurnal periods of protein sparing and degradation, with maximal rates of protein oxidation occurring at night and the lowest rates occurring during the day time. This stable isotope tracer method provides a noninvasive approach to study the nutrient dynamics of fasting animals and should provide new insights into how different types of animals use specific nutrient pools during fasting and possibly other non-steady physiological states. [Copyright &y& Elsevier]

Abstract: There is a perceived tradeoff between the ease of measuring alcohol in the body and the accuracy of the result. Direct tests of blood alcohol concentrations are considered the most accurate, desktop stationary breath testers based on electro-chemical infra-red technology are slightly less accurate, but accepted for evidentiary purposes in most jurisdictions, and quick portable breath testers based on fuel-cell technology are the easiest to administer but not acceptable in many courts. This study compared the accuracy of an evidentiary portable breath tester and an evidentiary desktop breath tester relative to blood alcohol concentrations. Inverse regressions were used to obtain confidence limits for the alcohol levels as read by the breath testers that would provide tradeoffs of false positives and false negatives for three levels of confidence: 95%, 96%, and 98%; corresponding to false positive values of 2.5%, 2%, and 1%, respectively. A decision tree model is offered for the optimal use of the three measures, so that portable breath testers can be sufficient for high level BrAC, stationary breath testers can be sufficient for medium level BrAC, and blood tests are recommended for still lower BrACs. The model provides quantitative BrAC threshold levels for the two most common BAC levels used to imply DWI: 50mg/dl and 80mg/dl. [Copyright &y& Elsevier]

Abstract: At present drugs of abuse testing using exhaled breath as specimen is only possible for alcohol. However, we recently discovered that using modern liquid chromatography–mass spectrometry technique amphetamine and methamphetamine is detectable in exhaled breath following intake in drug addicts. We therefore undertook to develop a method for determination of methadone in exhaled breath from patients undergoing methadone maintenance treatment. Exhaled breath was collected from 13 patients after intake of the daily methadone dose. The compounds were trapped by filtering the air through a C18 modified silica surface. After elution of any trapped methadone the extract was analysed by a combined liquid chromatography–tandem mass spectrometry method. Recovery of trapped methadone from the filter surface was 96%, no significant matrix effect was observed, and the quantification using methadone-d3 as an internal standard was accurate (<10% bias) and precise (coefficient of variation 1.6–2.0%). Methadone was indisputably identified by means of the mass spectrometry technique in exhaled breath samples from all 13 patients. Identification was based on monitoring two product ions in selected reaction monitoring mode with correct relative ratio (±20%) and correct retention time. Excretion rates ranged from 0.39 to 78ng/min. No methadone was detected in 10 control subjects. This finding confirms that breath testing is a new possibility for drugs of abuse testing. Collection of exhaled breath specimen is likely to be more convenient and safe as compared to other matrices presently in use. [ABSTRACT FROM AUTHOR]

Abstract: The 13C-urea breath test provides non-invasive testing for Helicobacter pylori infection with the possibility of analysis at the point of care. Point of care tests require accurate and efficient desktop instrumentation. Objective: : To compare results obtained from a new infrared spectrophotometer (10 kg, 2 min sample measurement) to the previously approved UBiT®-IR300 (22.5 kg, 5–6 min sample measurement). Design and methods: : Adults underwent urea breath testing; breath samples were analyzed using the new and the predicate instruments. Results: : There were 220 adults enrolled (age range 18–74 years; M/F = 35:65); with 86 UBT positive and 134 negative cases. The overall agreement between instruments was 99.6% (95% C.I. = 97.6 to 99.9); the positive agreement was 100%. Conclusion: : Technical performance of the new instrument was excellent. [Copyright &y& Elsevier]

This paper evaluates three approaches to compulsory breath testing (CBT) where all drivers stopped are tested: (1) intensive, moderate-profile CBT (plus zero alcohol tolerance for drivers under age 20, which was implemented simultaneously, remains in effect, and unavoidably is commingled with CBT in the effectiveness estimates); (2) CBT plus an enhanced media campaign; and (3) shifting to aggressively visible booze buses, which also streamlined drunk-driver processing, plus enhanced community campaigns against drunk-driving. Approaches 1 and 2 were implemented throughout New Zealand (NZ) in 1993 and 1995. Booze buses and community programs were added for about one-third of the country in late 1996. ARIMA time series models estimated the impact on serious and fatal injury crashes between 10 p.m. and 3 a.m., a proxy for alcohol-related crashes. A benefit–cost analysis assessed return on investment. Cost savings were analyzed from four perspectives: societal, governmental, drunk-drivers’, and people other than drunk-drivers (external cost). CBT plus zero tolerance reduced expected night-time crashes by 22.1% and enhanced media by 13.9%. Booze buses yielded a further 27.4% reduction where implemented. The program and associated crash reduction persisted until at least 2001 (the most recent data available). Estimated societal benefit–cost ratios were 14 for CBT, 19 for CBT plus enhanced media, and 26 for the comprehensive package. Government saved more than it spent on the program, especially with booze buses. Aggressive CBT plus zero alcohol tolerance for youth, media blitzes, and booze buses proved dramatically effective. Together, these four interventions halved late night serious and fatal injury crashes. Sustained effort seems to be critical. Better outcomes may be achieved with staged, increasingly visible and inescapable checkpoints than with an “ideal” initial program. It appears CBT is best implemented in conjunction with broader community-centered efforts to reduce drunk-driving. [Copyright &y& Elsevier]

The modified relative dose response (MRDR) test is widely used in public health research to assess vitamin A (VA) status of populations and individuals. However, method adjustments intended to make the test more useful in large field studies and/or less invasive have not been systematically verified. To compare the similarity between modified tests and the standard MRDR test, and validate both modified and standard tests against liver reserves of VA, we used a piglet model. Following the typical MRDR procedure, piglets (n = 10) were dosed with 5.3 micromol 3,4-didehydroretinyl acetate. Method adjustments were made to the postdose blood sample collection time to decrease both the amount of serum analyzed and sample throughput time. We collected 3 blood samples/piglet at 3, 5, and 7 h or 4, 6, and 8 h postdose. Postdose blood samples obtained between 4 and 7 h gave MRDR values that did not differ. Serum volumes as small as 200 microL, half the volume of the standard method, yielded accurate MRDR values. Method adjustments to reduce sample throughput time require further investigation. In conclusion, because 200 microL of serum can be used in the test, only 0.5 mL, as opposed to 1 mL of blood has to be collected from an individual. This adjustment allows for easier application of the test to individuals, especially infants, from whom it is difficult to obtain a large venous blood sample, thus increasing the utility of the test for researchers. [ABSTRACT FROM AUTHOR]

Background: Research on the effects of restricting bar opening hours and alcohol sales in middle-income countries is very limited. We assessed compliance with and possible effects of a law enacted in Zacatecas, Mexico on December 30, 2017 and implemented in 2018 and 2019 that established a 2 AM bar closing time and 10 PM cut-off for alcohol sales by off-premises stores.Methods: Monthly observations of bars and off-premises stores and alcohol mystery shopping visits from 2018 to early 2020 were conducted to assess compliance with the law. Breath tests were conducted in 2018 and 2019 with samples of pedestrians in the nighttime entertainment districts of Zacatecas and a comparison city (Aguascalientes). Surveys of bar owners/managers and staff, emergency medical personnel (EMP), and police officers were conducted in Zacatecas in 2018 and 2019 to assess awareness and support of the law and possible effects of the law on alcohol-related problems such as violence and injuries.Results: Monthly observations indicated that a substantial percentage of bars and off-premises package stores did not comply with the law. Pedestrian breath tests in 2018 and 2019 indicated significant reductions in blood alcohol concentration and heavy drinking among pedestrians in Zacatecas from 11 PM to 2 AM compared to Aguascalientes, but not after 2 AM. Surveys of bar owners/managers indicated that most were aware and supportive of the law. EMP surveys indicated reductions in incidents of physical fighting and drunk or injured customers during the annual September fair in Zacatecas.Conclusions: This study suggests that restricting bar opening hours and alcohol sales may not result in full compliance by bars and off-premises stores, but may help to reduce excessive alcohol use and related harms in a middle-income country. A more rigorous evaluation with pre-intervention data is needed, however, to fully address this latter question. [ABSTRACT FROM AUTHOR]

Abstract: A total of seventeen subjects were administered breath tests with alcohol dosed tobacco to see if there was an interference with the evidentiary breath testing. Fourteen subjects provided one set of two breath samples without the dosed tobacco followed by a set of two breath samples with the dosed tobacco. The other three subjects provided one breath sample without the dosed tobacco and then one breath sample with the dosed tobacco within the same testing sequence. Eight subjects had breath test readings of 0.00g/210L with the dosed tobacco. Mouth alcohol was detected with the dosed tobacco in six of the subjects, and a reading of 0.01g/210L, 0.04g/210L, and 0.05g/210L were found in five of the subjects. If the officer follows the directive of checking the mouth for a foreign substance and following a 15–20min observation/deprivation period, a false positive result will likely be avoided. If the officer does not find tobacco when checking the mouth for a foreign substance, and dosed tobacco is present during the breath test, most likely there would not be a measurable amount of alcohol to report or there would be a mouth alcohol reading from the sample. [Copyright &y& Elsevier]