Chronic ozone exposure preferentially modifies root rather than foliar metabolism of date palm (Phoenix dactylifera) saplings

In their natural environment, date palms are exposed to chronic atmospheric ozone (O₃) concentrations from local and remote sources. In order to elucidate the consequences of this exposure, date palm saplings were treated with ambient, 1.5 and 2.0 times ambient O₃ for three months in a free-air controlled exposure facility. Chronic O₃ exposure reduced carbohydrate contents in leaves and roots, but this effect was much stronger in roots. Still, sucrose contents of both organs were maintained at elevated O₃, though at different steady states. Reduced availability of carbohydrate for the Tricarboxylic acid cycle (TCA cycle) may be responsible for the observed reduced foliar contents of several amino acids, whereas malic acid accumulation in the roots indicates a reduced use of TCA cycle intermediates. Carbohydrate deficiency in roots, but not in leaves caused oxidative stress upon chronic O₃ exposure, as indicated by enhanced malonedialdehyde, H₂O₂ and oxidized glutathione contents despite elevated glutathione reductase activity. Reduced levels of phenolics and flavonoids in the roots resulted from decreased production and, therefore, do not indicate oxidative stress compensation by secondary compounds. These results show that roots of date palms are highly susceptible to chronic O₃ exposure as a consequence of carbohydrate deficiency.

Exploring new strategies for ozone-risk assessment: A dynamic-threshold case study

Tropospheric ozone is a dangerous atmospheric pollutant for forest ecosystems when it penetrates stomata. Thresholds for ozone-risk assessment are based on accumulated stomatal ozone fluxes such as the Phytotoxic Ozone Dose (POD). In order to identify the effect of ozone on a Holm oak forest in central Italy, four flux-based ozone impact response functions were implemented and tested in a multi-layer canopy model AIRTREE and evaluated against Gross Primary Productivity (GPP) obtained from observations of Eddy Covariance fluxes of CO₂. To evaluate if a clear phytotoxic threshold exists and if it changes during the year, six different detoxifying thresholds ranging between 0 and 5 nmol O₃ m^-2 s^-1 were tested. The use of species-specific rather than more general response functions based on plant functional types (PFT) increased model accuracy (RMSE reduced by up to 8.5%). In the case of linear response functions, a threshold of 1 nmol m^-2 s^-2 produced the best results for simulations of the whole year, although the tolerance to ozone changed seasonally, with higher tolerance (5 nmol m^-2 s^-1 or no ozone impact) for Winter and Spring and lower thresholds in Summer and Fall (0-1 nmol m^-2 s^-1). A "dynamic threshold" obtained by extracting the best daily threshold values from a range of different simulations helped reduce model overestimation of GPP by 213 g C m^-2 y^-1 and reduce RMSE up to 7.7%. Finally, a nonlinear ozone correction based on manipulative experiments produced the best results when no detoxifying threshold was applied (0 nmol O₃ m^-2 s^-1), suggesting that nonlinear functions fully account for ozone detoxification. The evidence of seasonal changes in ozone tolerance points to the need for seasonal thresholds to predict ozone damage and highlights the importance of performing more species-specific manipulative experiments to derive response functions for a broad range of plant species.

Empagliflozin confers reno-protection in acute myocardial infarction and type 2 diabetes mellitus

AIMS

Although the reno-protective effects of sodium-glucose cotransporter 2 inhibitors are known in patients with heart failure or type 2 diabetes mellitus (T2DM), this effect has not been confirmed in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

The prospective, multicentre, randomized, double-blind, placebo-controlled EMBODY trial investigated patients with AMI and T2DM in Japan. The eligible patients included adults aged 20 years or older, diagnosed with AMI and T2DM, and who could be discharged within 2-12 weeks after the onset of AMI. One hundred and five patients were randomized (1:1) to receive once daily 10 mg empagliflozin or placebo within 2 weeks of AMI onset. In this sub-analysis, we investigated the time course of renal functional parameters such as serum creatinine levels and estimated glomerular filtration rate (eGFR) from baseline to Weeks 4, 12, and 24. Ninety-six patients (64 ± 11 years, 78 male) were included in the full analysis (n = 46 and 50 in the empagliflozin and placebo groups, respectively). We used serum creatinine and eGFR as indicators of renal function. In the placebo group, eGFR decreased from 66.14 mL/min/1.73 m2 at baseline to 62.77 mL/min/1.73 m2 by Week 24 (P = 0.023) but remained unchanged in the empagliflozin group (from 64.60 to 64.36 mL/min/1.73 m2 , P = 0.843). In the latter group, uric acid improved from 5.8 mg/dL at baseline to 4.9 mg/dL at Week 24 (P < 0.001). In the earlier analysis of 56 patients with eGFR ≥ 60 mL/min/1.73 m2 , the eGFR decreased and the serum creatinine increased from baseline to 24 weeks in the placebo group, significantly different to the empagliflozin group (-6.61 vs. +0.22 mL/min/1.73 m2 , P = 0.008 and +0.063 vs. -0.001 mg/dL, P = 0.030, respectively). The changes in serum creatinine and eGFR from baseline to Week 24 were significantly correlated with those in uric acid in the placebo group (r = 0.664, P < 0.001 and r = -0.675, P < 0.001, respectively) but not in the empagliflozin group.

CONCLUSIONS

Empagliflozin prevented the kidney functional decline in patients with AMI and T2DM, especially those with baseline eGFR ≥ 60 mL/min/1.73 m2 . Early administration of sodium-glucose cotransporter 2 inhibitors in these patients is considered desirable for renal protection.

Effect of Empagliflozin Versus Placebo on Body Fluid Balance in Patients With Acute Myocardial Infarction and Type 2 Diabetes Mellitus: Subgroup Analysis of the EMBODY Trial

BACKGROUND

The development of heart failure is associated with fluid balance, including that of extracellular water (ECW) and intracellular water (ICW). This study determined whether sodium-glucose cotransporter 2 inhibitors affect fluid balance and improve heart failure in patients after acute myocardial infarction.

METHODS AND RESULTS

EMBODY was a prospective, randomized, double-blinded, placebo-controlled trial of Japanese patients with acute myocardial infarction and type 2 diabetes. Overall, 55 patients who underwent bioelectrical impedance analysis were randomized to receive once daily 10 mg empagliflozin or placebo 2 weeks after acute myocardial infarction onset. We investigated the time course of body fluid balance measured using the bioelectrical impedance analysis device, InBody. The primary end points were changes in body fluid balance from weeks 0 to 24. Changes between baseline and week 24 in the empagliflozin and placebo groups were -0.21 L (P = .127) and +0.40 L (P = .001) in ECW (P = .001) and -0.23 L (P = .264) and +0.74 L (P < .001) in ICW (P < .001), respectively. In a stratified analysis, the rise in ECW and ICW was significantly attenuated in the empagliflozin group in contrast to the placebo group in participants with a body mass index of 25 or higher but not in those with a body mass index of less than 25.

CONCLUSIONS

Early sodium-glucose cotransporter 2 inhibitor administration may attenuate changes in ECW and ICW.

Effect of Empagliflozin Versus Placebo on Plasma Volume Status in Patients with Acute Myocardial Infarction and Type 2 Diabetes Mellitus

INTRODUCTION

Plasma volume status (PVS), a parameter of the discrepancy between actual plasma volume (PV) and ideal PV, has been recently evaluated as a prognostic marker in patients with heart failure. This subgroup analysis of the EMBODY trial was designed to determine whether a sodium-glucose cotransporter 2 (SGLT2) inhibitor affects the alleviation of heart failure and improvement of PVS in patients after acute myocardial infarction (AMI) with congestive heart failure (CHF).

METHODS

The EMBODY trial was a prospective, multicenter, randomized, double-blind, placebo-controlled trial to identify the effect of an SGLT2 inhibitor on cardiac sympathetic hyperactivity in patients with AMI and type 2 diabetes mellitus (T2DM) in Japan. In total, 105 patients were randomized (1:1) to receive 10 mg empagliflozin or a placebo (once daily), 2 weeks after the onset of AMI. In this subanalysis, we investigated the time-course of PVS at baseline and weeks 4, 12, and 24.

RESULTS

Overall, 96 patients were included in the subgroup analysis set (age 64.3 ± 10.9 years, 80.2% men; 46 in the empagliflozin group and 50 in the placebo group). Body weight and PVS decreased in the empagliflozin group compared with the placebo group at 24 weeks (- 2.2 vs. + 0.1 kg, P < 0.001, and - 5.1 vs. - 0.3%, P < 0.001, respectively). Decreased PVS, defined as a change in PVS of < - 4.5%, was associated with the administration of empagliflozin (odds ratio 2.61, 95% confidence interval 1.11-6.15, P = 0.028). N-terminal pro b-type natriuretic peptide levels decreased in both the empagliflozin and placebo groups (1028.7-370.3 pg/mL, P < 0.001, and 1270.6-673.7 pg/mL, P < 0.01, respectively).

CONCLUSION

Empagliflozin reduced the body weight and PVS. Early SGLT2 inhibitor administration in patients with AMI, CHF, and T2DM can therefore be effective in reducing the body weight and PVS.

TRIAL REGISTRATION

UMIN 000030158.

Effect of empagliflozin versus placebo on body composition in patients with acute myocardial infarction and type 2 diabetes mellitus: subgroup analysis of the EMBODY trial

Background

Prevention of heart failure is one of the most important challenges after acute myocardial infarction (AMI). The development of heart failure is closely associated with fluid balance which can be evaluated by the measurement of body composition such as total body water (TBW), extracellular water (ECW), and intracellular water (ICW). This subgroup analysis of the EMBODY trial was designed to determine whether the Sodium–glucose cotransporter 2 (SGLT2) inhibitor affect fluid balance and improve heart failure in patients after AMI.

Methods

The EMBODY trial was a prospective, multicenter, randomized, double-blind, placebo-controlled trial in patients with AMI and type 2 diabetes in Japan. A total of 105 patients were randomized (1:1) to receive once-daily 10 mg empagliflozin, an SGLT2 inhibitor or placebo 2 weeks after the onset of AMI. In this subanalysis, we investigated the time-course of body composition measured by a bioelectrical impedance analyzer “InBody®”. The primary endpoints were changes in every particular parameter of body composition at week 0, 4, 12, and 24. Secondary endpoints were changes in blood pressure (BP), body weight and N-terminal pro b-type natriuretic peptide (NT-proBNP).

Results

Overall, 55 patients were included in the full analysis set (67.2±10.0 years, male 78.2%, and n=30 in empagliflozin group and 25 in placebo group). Baseline characteristics were not significantly different between the two groups. The change between at baseline and 24 weeks in TBW was −0.44 L (P=0.19) in the empagliflozin group and +1.14 L (P=0.0002) in the placebo group, adjusted difference −1.58 L, 95% confidence interval (CI) −2.46 to −0.70 L (P=0.0006). The empagliflozin group showed significant decreases in the body weight, ECW, ICW and systolic BP compared with the placebo group (−2.2 kg vs, +0.01 kg, P=0.004, −0.21 L vs, +0.40 L, P=0.001, −0.23 L vs, +0.74 L, P=0.0007, and −11.0 mmHg vs, +5.0 mmHg, P&lt;0.0001, respectively). On the other hand, NT-Pro BNP levels significantly decreased in the empagliflozin group and placebo group (1028.7 pg/mL to 370.3 pg/ml, p=0.0001 and 1270.6 pg/mL to 673.7 pg/ml, p=0.006, respectively). In the multiple regression analysis of the change in TBW and ICW for the empagliflozin group, systolic BP was identified as a significant factor (P=0.001, and 0.003, respectively). In stratified analysis of BMI 25 kg/m2 or more, the empagliflozin group showed significant decreases in body weight, TBW, ECW and ICW compared with the placebo group, but not below BMI 25 kg/m2 group.

Conclusion

Empagliflozin reduced not only body weight, but also TBW, ECW and ICW. Interestingly, this tendency was remarkable at BMI 25 or more. This study suggested that early SGLT2 inhibitor administration in obesity patients with AMI and DM might be effective to reduce body weight and TBW.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Boehringer Ingelheim

Effects of empagliflozin versus placebo on cardiac sympathetic activity in acute myocardial infarction patients with type 2 diabetes mellitus: the EMBODY trial

Background

Protection from lethal ventricular arrhythmias leading to sudden cardiac death (SCD) is a crucial challenge after acute myocardial infarction (AMI). Cardiac sympathetic and parasympathetic activity can be noninvasively assessed using heart rate variability (HRV) and heart rate turbulence (HRT). The EMBODY trial was designed to determine whether the Sodium–glucose cotransporter 2 (SGLT2) inhibitor improves cardiac nerve activity.

Methods

This prospective, multicenter, randomized, double-blind, placebo-controlled trial included patients with AMI and type 2 diabetes mellitus (T2DM) in Japan; 105 patients were randomized (1:1) to receive once-daily 10-mg empagliflozin or placebo. The primary endpoints were changes in HRV, e.g., the standard deviation of all 5-min mean normal RR intervals (SDANN) and the low-frequency–to–high-frequency (LF/HF) ratio from baseline to 24 weeks. Secondary endpoints were changes in other sudden cardiac death (SCD) surrogate markers such as HRT.

Results

Overall, 96 patients were included (46, empagliflozin group; 50, placebo group). The changes in SDANN were + 11.6 and + 9.1 ms in the empagliflozin (P = 0.02) and placebo groups (P = 0.06), respectively. Change in LF/HF ratio was – 0.57 and – 0.17 in the empagliflozin (P = 0.01) and placebo groups (P = 0.43), respectively. Significant improvement was noted in HRT only in the empagliflozin group (P = 0.01). Whereas intergroup comparison on HRV and HRT showed no significant difference between the empagliflozin and placebo groups. Compared with the placebo group, the empagliflozin group showed significant decreases in body weight, systolic blood pressure, and uric acid. In the empagliflozin group, no adverse events were observed.

Conclusions

This is the first randomized clinical data to evaluate the effect of empagliflozin on cardiac sympathetic and parasympathetic activity in patients with T2DM and AMI. Early SGLT2 inhibitor administration in AMI patients with T2DM might be effective in improving cardiac nerve activity without any adverse events.

Trial Registration: The EMBODY trial was registered by the UMIN in November 2017 (ID: 000030158). UMIN000030158; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000034442.

Toward stomatal-flux based forest protection against ozone: The MOTTLES approach

European standards for the protection of forests from ozone (O₃) are based on atmospheric exposure (AOT40) that is not always representative of O₃ effects since it is not a proxy of gas uptake through stomata (stomatal flux). MOTTLES "MOnitoring ozone injury for seTTing new critical LEvelS" is a LIFE project aimed at establishing a permanent network of forest sites based on active O₃ monitoring at remote areas at high and medium risk of O₃ injury, in order to define new standards based on stomatal flux, i.e. POD_Y (Phytotoxic Ozone Dose above a threshold Y of uptake). Based on the first year of data collected at MOTTLES sites, we describe the MOTTLES monitoring station, together with protocols and metric calculation methods. AOT40 and POD_Y, computed with different methods, are then compared and correlated with forest-health indicators (radial growth, crown defoliation, visible foliar O₃ injury). For the year 2017, the average AOT40 calculated according to the European Directive was even 5 times (on average 1.7 times) the European legislative standard for the protection of forests. When the metrics were calculated according to the European protocols (EU Directive 2008/50/EC or Modelling and Mapping Manual LTRAP Convention), the values were well correlated to those obtained on the basis of the real duration of the growing season (i.e. MOTTLES method) and were thus representative of the actual exposure/flux. AOT40 showed opposite direction relative to PODY. Visible foliar O₃ injury appeared as the best forest-health indicator for O₃ under field conditions and was more frequently detected at forest edge than inside the forest. The present work may help the set-up of further long-term forest monitoring sites dedicated to O₃ assessment in forests, especially because flux-based assessments are recommended as part of monitoring air pollution impacts on ecosystems in the revised EU National Emissions Ceilings Directive.

Ozone-induced stomatal sluggishness changes stomatal parameters of Jarvis-type model in white birch and deciduous oak

Stomatal ozone flux is closely related to ozone injury to plants. Jarvis-type multiplicative model has been recommended for estimating stomatal ozone flux in forest trees. Ozone can change stomatal conductance by both stomatal closure and less efficient stomatal control (stomatal sluggishness). However, current Jarvis-type models do not account for these ozone effects on stomatal conductance in forest trees. We examined seasonal course of stomatal conductance in two common deciduous tree species native to northern Japan (white birch: Betula platyphylla var. japonica; deciduous oak: Quercus mongolica var. crispula) grown under free-air ozone exposure. We innovatively considered stomatal sluggishness in the Jarvis-type model using a simple parameter, s, relating to cumulative ozone uptake (defined as POD: phytotoxic ozone dose). We found that ozone decreased stomatal conductance of white birch leaves after full expansion (-28%). However, such a reduction of stomatal conductance by ozone fell in late summer (-10%). At the same time, ozone reduced stomatal sensitivity of white birch to VPD and increased stomatal conductance under low light conditions. In contrast, in deciduous oak, ozone did not clearly change the model parameters. The consideration of both ozone-induced stomatal closure and stomatal sluggishness improved the model performance to estimate stomatal conductance and to explain the dose-response relationship on ozone-induced decline of photosynthesis of white birch. Our results indicate that ozone effects on stomatal conductance (i.e. stomatal closure and stomatal sluggishness) are crucial for modelling studies to determine stomatal response in deciduous trees, especially in species sensitive to ozone.

BVOC responses to realistic nitrogen fertilization and ozone exposure in silver birch

Emission of BVOC (Biogenic Volatile Organic Compounds) from plant leaves in response to ozone exposure (O3) and nitrogen (N) fertilization is poorly understood. For the first time, BVOC emissions were explored in a forest tree species (silver birch, Betula pendula) exposed for two years to realistic levels of O3 (35, 48 and 69 ppb as daylight average) and N (10, 30 and 70 kg ha(-1) yr(-1), applied weekly to the soil as ammonium nitrate). The main BVOCs emitted were: α-pinene, β-pinene, limonene, ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and hexanal. Ozone exposure increased BVOC emission and reduced total leaf area. The effect on emission was stronger when a short-term O3 metric (concentrations at the time of sampling) rather than a long-term one (AOT40) was used. The effect of O3 on total leaf area was not able to compensate for the stimulation of emission, so that responses to O3 at leaf and whole-plant level were similar. Nitrogen fertilization increased total leaf area, decreased α-pinene and β-pinene emission, and increased ocimene, hexanal and DMNT emission. The increase of leaf area changed the significance of the emission response to N fertilization for most compounds. Nitrogen fertilization mitigated the effects of O3 exposure on total leaf area, while the combined effects of O3 exposure and N fertilization on BVOC emission were additive and not synergistic. In conclusion, O3 exposure and N fertilization have the potential to affect global BVOC via direct effects on plant emission rates and changes in leaf area.

Effects of long-term ambient ozone exposure on biomass and wood traits in poplar treated with ethylenediurea (EDU)

This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.

RUNX1, but not its familial platelet disorder mutants, synergistically activates PF4 gene expression in combination with ETS family proteins

BACKGROUND

Familial platelet disorder (FPD) is a rare autosomal dominant disease characterized by thrombocytopenia and abnormal platelet function. Causal mutations have been identified in the gene encoding runt-related transcription factor 1 (RUNX1) of FPD patients.

OBJECTIVES

To elucidate the role of RUNX1 in the regulation of expression of platelet factor 4 (PF4) and to propose a plausible mechanism underlying RUNX1-mediated induction of the FPD phenotype.

METHODS

We assessed whether RUNX1 and its mutants, in combination with E26 transformation-specific-1 (ETS-1), Core-binding factor subunit beta (CBFβ), and Friend leukemia virus integration 1 (FLI-1), cooperatively regulate PF4 expression during megakaryocytic differentiation. In an embryonic stem cell differentiation system, expression levels of endogenous and exogenous RUNX1 and PF4 were determined by real-time RT-PCR. Promoter activation by the transcription factors were evaluated by reporter gene assays with HepG2 cells. DNA binding activity and protein interaction were analyzed by electrophoretic mobility shift assay and immunoprecipitation assay with Cos-7 cells, respectively. Protein localization was analyzed by immunocytochemistry and Western blotting with Cos-7 cells.

RESULTS

We demonstrated that RUNX1 activates endogenous PF4 expression in megakaryocytic differentiation. RUNX1, but not its mutants, in combination with ETS-1 and CBFβ, or FLI-1, synergistically activated the PF4 promoter. Each RUNX1 mutant harbors various functional abnormalities, including loss of DNA-binding activity, abnormal subcellular localization, and/or alterations of binding affinities for ETS-1, CBFβ, and FLI-1.

CONCLUSIONS

RUNX1, but not its mutants, strongly and synergistically activates PF4 expression along with ETS family proteins. Furthermore, loss of the RUNX1 transcriptional activation function is induced by various functional abnormalities.

[The role and significance of acid suppressive drugs in the eradication of H. pylori]

Recently a new triple therapy with PPI and two antimicrobials is widely accepted instead of classical triple therapy. PPI has direct and indirect effects on H. pylori. Practically a single use of PPI is almost noneffective for eradication of H. pylori. In the combination therapy PPI is supposed to contribute to successful eradication through the inhibition of acid secretion. Because a raise of pH in stomach protects antimicrobials from the degradation by acidic environment. The decrease in the volume of gastric juice also contributes to concentrate antibiotics. Recently interaction between PPI and clarithromycin on metabolic enzyme in liver was reported that explains the synergistic effects of these drugs. The heterogeneity of genotype of metabolic enzyme was also elucidated which might be responsible for the difference in the effect of PPI between the patients. To accomplish successful eradication, full inhibition of acid secretion has to be done. To consider the interactions between PPI and antimicrobials and the heterogeneity of genotype of metabolic enzyme may improve eradication therapy of H. pylori.

Characterization of trace amounts of odorants (sulfur compounds, oxygenates, hydrocarbons, phenols and lower fatty acids) in air in an ICU room

Characterization of trace amounts of odorants in air in an ICU room (ca.257m2) was carried out by gas chromatography and atmospheric pressure ionization-mass spectrometry (API-MS). The concentrations and odor recognition threshold values of the detected odorants, acetaldehyde, ethanol, n-butyric acid, iso-valeric acid and n-valeric acid are as follows: 44.7 ppb and 15 ppb; 19710 ppb and 6100 ppb; 0.50 ppb and 0.4 ppb; 0.45 ppb and 0.4 ppb; 0.67 ppb and 0.5 ppb, respectively. The detected concentrations of these odorants were significantly higher than the odor recognition threshold values. The compounds may, therefore, be responsible for perception of such odors as mixed odors, body odor, and faint or recognizable alcoholic odor, disinfectant odor, and sour, pungent, and goat odors.

International comparison of odor threshold values of several odorants in Japan and in The Netherlands

The purpose of this paper is to compare the published odor threshold values of six odorants. In Japan, all of the odor threshold values used in the Offensive Odor Control Law (enacted in 1972) were determined in an odor-free room (4 m3) by a trained panel (20 men, ages 30-45 years who were perfumers) who sniffed the odors directly and made absolute judgments of odor quality and intensity. In The Netherlands, sensorial odor concentration measurements were made with an olfactometer in a mobile sniffing car with eight panelists, four men and four women, ages 18-40 years. Such presentations are repeated with different dilution ratios. Comparison of the threshold data for the six different compounds given as the barely perceptible concentration level revealed striking similarities for hydrogen sulfide (in Japan 0.0005 ppm/in The Netherlands 0.0003 ppm), phenol (0.012/0.010), styrene (0.033/0.016), toluene (0.92/0.99), and tetrachloroethylene (1.8/1.2) but not for m-xylene (0.012/0.12). Such a similarity was not found with any other literature sources.

Gas chromatographic determination of indoles in human mouth and saliva using a flameless alkali sensitized detector (nitrogen/phosphorous-specific detector, NPD)

A simple and sensitive NPD determination of the indoles in the mouth and saliva of a nonsmoker and a smoker was investigated. The present method using NPD detection was found to be suitable for the analysis of the odors in human mouth based on the indoles.

Simple circular odor chart for characterization of trace amounts of odorants discharged from thirteen odor sources

A simple circular odor chart is proposed for the explanation of the relationship between sensory responses (to odor quality and intensity) to odors and chemical analysis data of the odorants responsible for each odor discharged from thirteen odor sources. The odorants were classified into eight odorant groups and were analyzed by a systematic gas chromatographic (GC) technique. The characterization of the trace amounts of the odorants was carried out by using the values of a new proposed unit (pOU) based on the ratio of detected concentration to recognition threshold value. The calculated pOU values of the eight groups were plotted in circular charts. It was found that the shape and size of each circular odor chart represent the quality and the intensity of each odor.

Simultaneous gas chromatographic analysis of lower fatty acids, phenols and indoles using a glass capillary column

The simultaneous gas chromatographic separation of a mixture of 14 lower fatty acis, 11 phenols and 7 indoles has been effected by using a glass capillary column. Complete separation of the mixture has been obtained, except for phenol and o-cresol and o-ethylphenol and 3,5-xylenol whose peaks overlapped, and 2- and 3-methylindoles which were poorly separated. The optimum conditions are as follows: stationary phase, FFAP or PEG-20M; column (20 m X 0.28 mm I.D.) temperature, held for 1 min at 145 degrees (FFAP) or 130 degrees (PEG-20M); column oven, heated at 4 degrees/min from 145 or 130 to 180 degrees (FFAP) or 165 degrees (PEG-20M), maintained at 180 or 165 degrees for 30 min; carrier gas (helium) flow-rate, 0.6 ml/min (FFAP), 1.3 ml/min (PEG-20M); flame ionization detector. The method has been applied to the analysis of lower fatty acids, phenols and indoles in Japanese cigarette smoke, where the peaks were identified by the disappearance method using an alkaline pre-column.

Simple and rapid gas-liquid-solid chromatographic analysis of trace concentrations of acetaldehyde in urban air

A simple and rapid gas-liquid-solid chromatographic method for the analysis of trace concentrations of acetaldehyde in urban air (in the Nagoya area) was developed, with the use of cold trapping with liquid oxygen. In the analytical main column the conditions were: stationary phase, Triton X-100 (0.4%); support, Carbopack B (60-80 mesh); glass column, 1.5 m X 3 mm I.D.; column temperature, 75 degrees; carrier gas (nitrogen) flow-rate, 50-80 ml/min. In the cold trapping pre-column the conditions were: stationary phase, Tris (2-cyanoethoxy) propane (25%); support, Shimalite (AW, DMCS) (60-80 mesh); glass column, 31 cm X 4 mm I.D.; operating temperature for the trapping, -183 degrees (liquid oxygen temperature); operating temperature for injection of the condensed sample into the gas chromatograph, increased from -183 degrees to +100 degrees for 2 min. The acetaldehyde peak was identified by the disappearance method with a 2,4-dinitrophenylhydrazine-orthophosphoric acid-glass beads column. The ranges and average concentrations of acetaldehyde detected in 13 urban air samples were 1.5-9.6 and 4.7 ppb, respectively.

Gas chromatographic determination of styrene as its dibromide

The selective and sensitive gas chromatographic determination of trace amounts of styrene was studied. Styrene was converted into styrene dibromide by reaction with bromine, and the latter was detected with an electron-capture detector. The minimum detectable amount of the dibromide was about 0.01 ng and the sensitivity to the dibromide was about 500 times higher than the sensitivity of a flame-ionization detector to the styrene monomer. Dodecene-1 and o- and m-cresol gave the greatest interference, but the cresols could easily be removed by reaction with a small amount of a dilute aqueous alkaline solution. The application to a practical specimen, namely urban air, is described.

Gas chromatographic determination of sulphur compounds in town gas

The gas chromatographic (GC) determination of the sulphur compounds in town gas (in the Nagoya area) was studied by using a flame-photometric detector (FPD) and the cold-trap method with liquid oxygen. The column packings used were 25% TCEP on Shimalite (AW, DMCS), 25% TCP on Shimalite (AW, DMCS), 10% PPE on Shimalite TPA, Porapak Q and silica gel. The major components identified were carbonyl sulphide, hydrogen sulphide, carbon disulphide, thiophene and tetrahydrothiophene (THT). The identities of thiophene and THT were also confirmed by GC combined with the use of a quadrupole mass spectrometer. The average concentrations and standard deviations of thiophene and THT were 8.8 +/- 1.8and 124 +/- 35 ng per 0.051, respectively. The latter value corresponds to 0.7 ppm, which is relatively high for the concentration of an odorant.

Wolff-Parkinson-White syndrome: mechanocardiographic study on the mechanical consequences of ventricular pre-excitation

To elucidate the mechanical consequences of ventricular pre-excitation in patients with the W,W syndrome, electrical and mechanical events in the ventricles during anomalous pathway conduction and normal atrioventricular conduction were examined mechanocardiographically in 11 cases of Group A and 19 cases of Group B, in whom anomalous pathway conduction was stopped by procaine amide, resulting in normalization of conduction. Eight healthy persons were employed as a control group. In the control group, procaine amide had no significant effect on the mechanocardiographic values. In the WPW syndrome, significant prolongation of the P-X, P-J, P-T, P-C, P-I, P-Ao, and P-II intervals was induced by the drug. From the results of statistical analyses of measured values, it would appear that mechanical events in the ventricles were accelerated by ventricular pre-excitation but the extent of acceleration of the former was less than the extent of prematurity of the latter. The anomalous ventricular pre-excitation occurred earlier in cases of Group B than in those of Group A, while initiation of ventricular contraction, atrioventricular valve closure, and aortic vlave opening were accelerated more in Group A. In one case of Group B, electrical phenomena could not be related to mechanical events.