9 research outputs found
Automated office blood pressure measurements in primary care are misleading in more than one third of treated hypertensives: The VALENTINE-Greece Home Blood Pressure Monitoring study
Abstract Background This study assessed the diagnostic reliability of automated office blood pressure (OBP) measurements in treated hypertensive patients in primary care by evaluating the prevalence of white coat hypertension (WCH) and masked uncontrolled hypertension (MUCH) phenomena. Methods Primary care physicians, nationwide in Greece, assessed consecutive hypertensive patients on stable treatment using OBP (1 visit, triplicate measurements) and home blood pressure (HBP) measurements (7 days, duplicate morning and evening measurements). All measurements were performed using validated automated devices with bluetooth capacity (Omron M7 Intelli-IT). Uncontrolled OBP was defined as â„140/90 mmHg, and uncontrolled HBP was defined as â„135/85 mmHg. Results A total of 790 patients recruited by 135 doctors were analyzed (age: 64.5 ± 14.4 years, diabetics: 21.4%, smokers: 20.6%, and average number of antihypertensive drugs: 1.6 ± 0.8). OBP (137.5 ± 9.4/84.3 ± 7.7 mmHg, systolic/diastolic) was higher than HBP (130.6 ± 11.2/79.9 ± 8 mmHg; difference 6.9 ± 11.6/4.4 ± 7.6 mmHg, p Conclusions In primary care, automated OBP measurements are misleading in approximately 40% of treated hypertensive patients. HBP monitoring is mandatory to avoid overtreatment of subjects with WCH phenomenon and prevent undertreatment and subsequent excess cardiovascular disease in MUCH
Development of an instrument for direct ozone production rate measurements: measurement reliability and current limitations
Ground-level ozone (O3) is an important pollutant that
affects both global climate change and regional air quality, with
the latter linked to detrimental effects on both human health and ecosystems.
Ozone is not directly emitted in the atmosphere but is formed from chemical
reactions involving volatile organic compounds (VOCs), nitrogen
oxides (NOxâ=ââŻNOâŻ+âŻNO2) and sunlight. The photochemical
nature of ozone makes the implementation of reduction strategies challenging
and a good understanding of its formation chemistry is fundamental in order
to develop efficient strategies of ozone reduction from mitigation measures
of primary VOCs and NOx emissions.
An instrument for direct measurements of ozone production rates (OPRs) was
developed and deployed in the field as part of the IRRONIC (Indiana Radical,
Reactivity and Ozone Production Intercomparison) field campaign. The OPR
instrument is based on the principle of the previously published MOPS
instrument (Measurement of Ozone Production Sensor) but using a different
sampling design made of quartz flow tubes and a different Ox (O3
and NO2) conversionâdetection scheme composed of an O3-to-NO2
conversion unit and a cavity attenuated phase shift spectroscopy (CAPS) NO2 monitor.
Tests performed in the laboratory and in the field, together with model
simulations of the radical chemistry occurring inside the flow tubes, were
used to assess (i)Â the reliability of the measurement principle and (ii)Â potential biases associated with OPR measurements.
This publication reports the first field measurements made using this
instrument to illustrate its performance. The results showed that a
photo-enhanced loss of ozone inside the sampling flow tubes disturbs the
measurements. This issue needs to be solved to be able to perform accurate
ambient measurements of ozone production rates with the instrument described
in this study. However, an attempt was made to investigate the OPR
sensitivity to NOx by adding NO inside the instrument. This type of
investigations allows checking whether our understanding of the turnover
point between NOx-limited and NOx-saturated regimes of ozone
production is well understood and does not require measuring ambient OPR but
instead only probing the change in ozone production when NO is added. During
IRRONIC, changes in ozone production rates ranging from the limit of
detection (3Ï) of 6.2âŻppbvâŻhâ1 up to 20âŻppbvâŻhâ1 were
observed when 6âŻppbv of NO was added into the flow tubes
Boleslaus Lukaszewski (Father Luke) Photographs. Roll 738, Image 005
Roll 738. Fr. Tom Thro, S. J. Image 5 of 9. (21 June 1961) [PHO 1.738.5]The Boleslaus Lukaszewski (Father Luke) Photographs contain more than 28,000 images of Saint Louis University people, activities, and events between 1951 and 1970. The photographs were taken by Boleslaus Lukaszewski (Father Luke), a Jesuit priest and member of the University's Philosophy Department faculty
Peroxy radical measurements by ethane - nitric oxide chemical amplification and laser-induced fluorescence during the IRRONIC field campaign in a forest in Indiana
Peroxy radicals were measured in a mixed deciduous forest atmosphere in Bloomington, Indiana, USA, during the Indiana Radical, Reactivity and Ozone Production Intercomparison (IRRONIC) during the summer of 2015. Total peroxy radicals ([XO]âĄ[HO]+ÎŁ[RO]) were measured by a newly developed technique involving chemical amplification using nitric oxide (NO) and ethane (CH) followed by NO detection by cavity-attenuated phase-shift spectroscopy (hereinafter referred to as ECHAMP â Ethane CHemical AMPlifier). The sum of hydroperoxy radicals (HO) and a portion of organic peroxy radicals ([HO]=[HO]+[RiO], 0<α<1) was measured by the Indiana University (IU) laser-induced fluorescenceâfluorescence assay by gas expansion instrument (LIF-FAGE). Additional collocated measurements include concentrations of NO, NO, O, and a wide range of volatile organic compounds (VOCs) and meteorological parameters. XO concentrations measured by ECHAMP peaked between 13:00 and 16:00 local time (LT), with campaign average concentrations of 41±15âppt (1Ï) at 14:00âLT. Daytime concentrations of isoprene averaged 3.6±1.9âppb (1Ï), whereas average concentrations of NO ([NO]â+â[NO]) and toluene were 1.2 and 0.1âppb, respectively, indicating a low impact from anthropogenic emissions at this site. We compared ambient measurements from both instruments and conducted a calibration source comparison. For the calibration comparison, the ECHAMP instrument, which is primarily calibrated with an acetone photolysis method, sampled the output of the LIF-FAGE calibration source which is based on the water vapor photolysis method and, for these comparisons, generated a 50â%â50â% mixture of HO and either butane or isoprene-derived RO. A bivariate fit of the data yields the relation [XO]=(0.88±0.02;[HO ]+[RO ])_{\textrm{IU_cal}}+(6.6±4.5)âppt. This level of agreement is within the combined analytical uncertainties for the two instruments' calibration methods. A linear fit of the daytime (09:00â22:00âLT) 30âmin averaged [XO] ambient data with the 1âmin averaged [HO] data (one point per 30âmin) yields the relation [XO]=(1.08±0.05)[HO]â(1.4±0.3). Day-to-day variability in the [XO]/[HO] ratio was observed. The lowest [XO ]/[HO] ratios between 13:00 and 16:00âLT were 0.8 on 13 and 18 July, whereas the highest ratios of 1.1 to 1.3 were observed on 24 and 25 July â the same 2âd on which the highest concentrations of isoprene and ozone were observed. Although the exact composition of the peroxy radicals during IRRONIC is not known, zero-dimensional photochemical modeling of the IRRONIC dataset using two versions of the Regional Atmospheric Chemistry Mechanism (RACM2 and RACM2 -LIM1) and the Master Chemical Mechanism (MCM 3.2 and MCM 3.3.1) all predict afternoon [XO]/[HO] ratios of between 1.2 and 1.5. Differences between the observed ambient [XO]/[HO] ratio and that predicted with the 0-D modeling can be attributed to deficiencies in the model, errors in one of the two measurement techniques, or both. Time periods in which the ambient ratio was less than 1 are definitely caused by measurement errors (including calibration differences), as such ratios are not physically meaningful. Although these comparison results are encouraging and demonstrate the viability in using the new ECHAMP technique for field measurements of peroxy radicals, further research investigating the overall accuracy of the measurements and possible interferences from both methods is warranted
Automated office blood pressure measurements in primary care are misleading in more than one third of treated hypertensives: The VALENTINE-Greece Home Blood Pressure Monitoring study
Background: This study assessed the diagnostic reliability of automated office blood pressure (OBP) measurements in treated hypertensive patients in primary care by evaluating the prevalence of white coat hypertension (WCH) and masked uncontrolled hypertension (MUCH) phenomena. Methods: Primary care physicians, nationwide in Greece, assessed consecutive hypertensive patients on stable treatment using OBP (1 visit, triplicate measurements) and home blood pressure (HBP) measurements (7 days, duplicate morning and evening measurements). All measurements were performed using validated automated devices with bluetooth capacity (Omron M7 Intelli-IT). Uncontrolled OBP was defined as â„140/90 mmHg, and uncontrolled HBP was defined as â„135/85 mmHg. Results: A total of 790 patients recruited by 135 doctors were analyzed (age: 64.5 ± 14.4 years, diabetics: 21.4%, smokers: 20.6%, and average number of antihypertensive drugs: 1.6 ± 0.8). OBP (137.5 ± 9.4/84.3 ± 7.7 mmHg, systolic/diastolic) was higher than HBP (130.6 ± 11.2/79.9 ± 8 mmHg; difference 6.9 ± 11.6/4.4 ± 7.6 mmHg, p < 0.001). WCH phenomenon (high OBP with low HBP) was observed in 22.7% of the patients, MUCH (low OBP with high HBP) in 15.8%, uncontrolled hypertension (high OBP with high HBP) in 29.9%, and controlled hypertension (low OBP with low HBP) in 31.6%. In multivariate logistic regression analysis, WCH was determined by stage-1 systolic hypertension (odds ratio [OR] 8.6, 95% confidence intervals [CI] 5.7, 13.1) and female gender (OR 1.6, 95% CI 1.1, 2.4), whereas MUCH was determined by high-normal systolic OBP (OR 6.2, 95% CI 3.8, 10.1) and male gender (OR 2.0, 95% CI 1.2, 3.1). Conclusions: In primary care, automated OBP measurements are misleading in approximately 40% of treated hypertensive patients. HBP monitoring is mandatory to avoid overtreatment of subjects with WCH phenomenon and prevent undertreatment and subsequent excess cardiovascular disease in MUCH. © 2019 Hellenic Society of Cardiolog