Measurement Of Nitric Oxide Research Articles

Investigation of non-target gas interferences on a multi-gas cavity ring-down spectrometer

Emissions from agriculture are a worldwide problem as it is the major anthropogenic source of ammonia, methane, and nitrous oxide. Several efforts have been made to mitigate emissions. To achieve this, reliable measuring techniques are necessary to quantify the impact of the emissions. Different techniques relying on different principles are available. Generally, these techniques demonstrate good agreement on their measurements but there is a lack of studies that thoroughly investigate cross-interferences. In this work, three different models of Cavity Ring-Down Spectrometers measuring ammonia, nitrous oxide, and methane were tested in parallel for potential biases due to interference from ammonia, water vapor, and twelve volatile organic compounds commonly present in agricultural environments. Our results showed a small negative bias with increasing humidity on nitrous oxide and minor interferences of ammonia on nitrous oxide and methane. None of the tested volatile organic compounds interfered with ammonia, methane, or nitrous oxide measurements. Overall, concentration measurements of ammonia, nitrous oxide, and methane with cavity ring-down spectrometry have proven reliable under typical agricultural conditions. Minor interferences were only observed under exceptional conditions.

Elevated Saliva Pepsin Concentration as a Risk Factor for Asthma in Children with Allergic Rhinitis: A Preliminary Study.

This study aimed to explore whether saliva pepsin concentration (SPC) could be regarded as a risk factor for the occurrence and unfavorable control of asthma in children with allergic rhinitis. A prospective study was conducted on a group of 20 consecutive children newly diagnosed with allergic rhinitis and asthma (referred to as the asthma group). All these children underwent fractional exhaled nitric oxide (FeNO) measurement, lung function tests, and assessment of asthma control using the 7-item Childhood Asthma Control Test (C-ACT) score. Simultaneously, a control group consisting of 20 children with simple allergic rhinitis, matched for baseline characteristics, was included. SPC measurement was performed in the two groups. The SPC value was significantly higher in the asthma group than that in the control group (165.0 ± 82.8 ng/mL vs 68.4 ± 34.5 ng/mL) (P < 0.001). In the asthma group, SPC was independently associated with FeNO, the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC), and forced expiratory flow at 50% and 75% of FVC (FEF50 and FEF75) (all P < 0.05). The severity of nasal symptoms evaluated by the visual analogue scale (N-VAS) was independently associated with FEF75, the maximal mid-expiratory flow (MMEF), and C-ACT score (P < 0.05). Direct pepsin exposure and uncontrolled nasal symptoms may play crucial roles in the pathogenesis and progression of childhood allergic asthma. The SPC value can be considered as a risk factor for asthma in children with allergic rhinitis.

Diagnosis and therapy of patients with asthma in Germany. Results of the care study RELEVANT

Diagnostic and therapeutic options for asthma have improved with asthma control and remission being of central importance. The RELEVANT study aimed for a nationwide snapshot of current asthma diagnosis and treatment in general practice and specialty care for identification of further aspects for optimization. RELEVANT is a nationwide cross-sectional study using a structured questionnaire. This comprised 14 questions on asthma-related topics covering diagnostics and therapy. Participants were general practitioners/internal medicine specialists and pulmonologists. A total of 1,558 persons took part in the survey. Regarding relevant specific diagnostic procedures for asthma, GPs/internists almost exclusively mentioned pulse oximetry. Among the pulmonologists, fractional exhaled nitric oxide (FeNO) measurement was mentioned, among others. FeNO and blood eosinophils were only mentioned by the pulmonologists as diagnostic and treatment-relevant markers. A total of more than 60% of the GPs/internists surveyed stated that only around 25% or fewer of their patients would voluntarily report restrictions in their everyday lives. Regarding drug treatment, the majority stated that they recognized differences between various ICS/LABA combination therapies. The results indicate a need for optimization, particularly regarding asthma control. This involves both a better assessment by patients' everyday life restrictions and modern ways of assessing asthma control in cooperation between GPs/internal medicine specialists and pulmonologists. One fifth of respondents do not see any differences between various ICS/LABA combinations in daily practice, although there are pharmacodynamic and pharmacokinetic differences.

Post-fire soil greenhouse gas fluxes in boreal Scots pine forests–Are they affected by surface fires with different severities?

Although forest fires are one of the main natural disturbance types in boreal forests, there is limited information regarding surface fires (dominant in Northern Europe), and how surface fires of different severities could affect post-fire soil greenhouse gas emissions. The results of our study show that fire severity, time since fire and post-fire changes in soil temperature were the main factors driving soil carbon dioxide (CO2) flux (forest floor ecosystem respiration) from burned boreal forest soils. Approximately two hours after the fire, soil CO2 emissions from burned areas were significantly higher compared to pre-fire conditions, and areas with high-severity fires had significantly higher soil CO2 emissions compared to those with low-severity fires. Later (days, months) after the fire, the unburned control areas always had higher soil CO2 emission values compared to burned areas. In the case of methane (CH4), time since fire and post-fire changes in soil temperatures were the main factors driving soil CH4 fluxes. Unburned study areas were sinks of CH4 through the entire measurement period, while immediately after the fire, the burned areas turned from CH4 sink to CH4 source. For nitrous oxide (N2O) measurements, time since fire was the only factor that significantly affected soil N2O fluxes. Shortly after the fire, N2O emissions increased significantly from both low- and high-intensity study plots. Two days after the fire, post-fire soil C and N content decreased in the O-horizon and increased within the first 5 cm of the soil mineral layer, and the trend was visible both in low- and high-severity fire plots. Samples collected four months after the fire, showed similar total soil C and N content as there was before the fire.

Propionyl-l-carnitine mitigates ischemia-reperfusion injury in rat epigastric island flaps

BackgroundIschemia-reperfusion injury presents a substantial concern in various medical scenarios, notably in reconstructive surgery involving tissue flaps. Despite reports on the protective benefits of Propionyl-l-carnitine against ischemia-reperfusion injury, a thorough assessment of its efficacy in epigastric island flap models is currently lacking. MethodsSixteen male Sprague-Dawley rats underwent epigastric island flap surgery and were divided into two groups: a Propionyl-l-carnitine group that received intraperitoneal Propionyl-l-carnitine prior to ischemia induction and a sham group that received saline treatment. A comprehensive evaluation was performed including macroscopic, biochemical and histological assessments encompassing measurements of flap survival areas, lipid peroxidation (malondialdehyde), glutathione, myeloperoxidase, nitric oxide and peripheral neutrophil counts. ResultsThe Propionyl-l-carnitine group demonstrated significantly increased flap survival areas when compared to the sham group. Administration of Propionyl-l-carnitine led to reduced malondialdehyde levels and elevated glutathione levels indicating a reduction in oxidative stress. Furthermore, the Propionyl-l-carnitine group exhibited lower myeloperoxidase levels, higher nitric oxide levels and reduced peripheral neutrophil counts, suggesting a decrease in the inflammatory response. Histopathological analysis revealed decreased levels of inflammation, necrosis, polymorphonuclear leukocyte infiltration and edema in the Propionyl-l-carnitine group. Additionally, vascularity was enhanced in the Propionyl-l-carnitine group. ConclusionThis study provides compelling evidence that Propionyl-l-carnitine administration effectively mitigates the deleterious effects of ischemia-reperfusion injury in epigastric island flaps. This is substantiated by the improved flap survival, diminished oxidative stress and inflammation, as well as the enhanced vascularity observed. Propionyl-l-carnitine emerges as a promising therapeutic intervention to enhance tissue flap survival in reconstructive surgery, warranting further exploration through larger-scale investigations.

Inequalities in urban air pollution in sub-Saharan Africa: an empirical modeling of ambient NO and NO2 concentrations in Accra, Ghana.

Road traffic has become the leading source of air pollution in fast-growing sub-Saharan African cities. Yet, there is a dearth of robust city-wide data for understanding space-time variations and inequalities in combustion related emissions and exposures. We combined nitrogen dioxide (NO2) and nitric oxide (NO) measurement data from 134 locations in the Greater Accra Metropolitan Area (GAMA), with geographical, meteorological, and population factors in spatio-temporal mixed effects models to predict NO2 and NO concentrations at fine spatial (50 m) and temporal (weekly) resolution over the entire GAMA. Model performance was evaluated with 10-fold cross-validation (CV), and predictions were summarized as annual and seasonal (dusty [Harmattan] and rainy [non-Harmattan]) mean concentrations. The predictions were used to examine population distributions of, and socioeconomic inequalities in, exposure at the census enumeration area (EA) level. The models explained 88% and 79% of the spatiotemporal variability in NO2 and NO concentrations, respectively. The mean predicted annual, non-Harmattan and Harmattan NO2 levels were 37 (range: 1-189), 28 (range: 1-170) and 50 (range: 1-195) µg m-3, respectively. Unlike NO2, NO concentrations were highest in the non-Harmattan season (41 [range: 31-521] µg m-3). Road traffic was the dominant factor for both pollutants, but NO2 had higher spatial heterogeneity than NO. For both pollutants, the levels were substantially higher in the city core, where the entire population (100%) was exposed to annual NO2 levels exceeding the World Health Organization (WHO) guideline of 10 µg m-3. Significant disparities in NO2 concentrations existed across socioeconomic gradients, with residents in the poorest communities exposed to levels about 15 µg m-3 higher compared with the wealthiest (p < 0.001). The results showed the important role of road traffic emissions in air pollution concentrations in the GAMA, which has major implications for the health of the city's poorest residents. These data could support climate and health impact assessments as well as policy evaluations in the city.

MONITORING IN VITRO AND EX VIVO INFLAMMATION USING SINGLE-WALLED CARBON NANOTUBES (SWCNTS) SENSOR TECHNOLOGY

Osteoarthritis (OA) is a degenerative joint disease affecting millions worldwide. Early detection of OA and monitoring its progression is essential for effective treatment and for preventing irreversible damage. Although sensors have emerged as a promising tool for monitoring analytes in patients, their application for monitoring the state of pathology is currently restricted to specific fields (such as diabetes). In this study, we present the development of an optical sensor system for real-time monitoring of inflammation based on the measurement of nitric oxide (NO), a molecule highly produced in tissues during inflammation.Single-walled carbon nanotubes (SWCNT) were functionalized with a single-stranded DNA (ssDNA) wrapping designed using an artificial intelligence approach and tested using S-nitroso-N-acetyl penicillamine (SNAP) as a standard released-NO marker. An optical SWIR reader with LED excitation at 650 nm, 730 nm and detecting emission above 1000 nm was developed to read the fluorescence signal from the SWCNTs. Finally, the SWCNT was embedded in GelMa to prove the feasibility of monitoring the release of NO in bovine chondrocyte and osteochondral inflamed cultures (1–10 ng/ml IL1β) monitored over 48 hours. The stability of the inflammation model and NO release was indirectly validated using the Griess and DAF-FM methods. A microfabricated sensor tag was developed to explore the possibility of using ssDNA-SWCNT in an ex vivo anatomic set-up for surgical feasibility, the limit of detection, and the stability under dynamic flexion.The SWCNT sensor was sensitive to NO in both in silico and in vitro conditions during the inflammatory response from chondrocyte and osteochondral plug cultures. The fluorescence signal decreased in the inflamed group compared to control, indicating increased NO concentration. The micro-tag was suitable and stable in joints showing a readable signal at a depth of up to 6 mm under the skin.The ssDNA-SWCNT technology showed the possibility of monitoring inflammation continuously in an in vitro set-up and good stability inside the joint. However, further studies in vivo are needed to prove the possibility of monitoring disease progression and treatment efficacy in vivo.Acknowledgments: The project was co-financed by Innosuisse (grant nr. 56034.1 IP-LS)

Measurement of Reactive Oxygen Species and Nitric Oxide from Tomato Plants in Response to Abiotic and Biotic Stresses.

Nitric oxide (NO) is a free radical molecule that has been known to influence several cellular processes such as plant growth, development, and stress responses. NO together with reactive oxygen species (ROS) play a role in signaling process. Due to extremely low half-life of these radicals in cellular environment, it is often difficult to precisely monitor them. Each method has some advantages and disadvantages; hence, it is important to measure using multiple methods. To interpret the role of each signaling molecule in numerous biological processes, sensitive and focused methods must be used. In addition to this complexity, these Reactive Oxygen Species (ROS) and NO react with each other leads to nitro-oxidative stress in plants. Using tomato as a model system here, we demonstrate stepwise protocols for measurement of NO by chemiluminescence, DAF fluorescence, nitrosative stress by western blot, and ROS measurement by NBT and DAB under stress conditions such as osmotic stress and Botrytis infection. While describing methods, we also emphasized on benefits, drawbacks, and broader applications of these methods.

Total airway mechanics and fractional exhaled nitric oxide levels of children living in banjihas (semi-basements).

The ISAAC phase III study in Korea found a higher incidence of wheezing illnesses among residents in basements or semi-basements. This study investigates the link between living in banjihas (semi-basements) and airway resistance and Th2 airway inflammation in Korean children, compared to those on higher floors. We assessed 575 fifth- and sixth-grade students (aged 10-12) in an inner-city area of South Korea. The study utilized impulse oscillometry to measure small and total airway resistance (Rrs20-5 and Rrs0, respectively) and Fractional Exhaled Nitric Oxide (FeNO) measurements to evaluate airway inflammation. We also considered a range of biological and environmental factors, including allergen sensitization, serum 25-hydroxyvitamin D levels, and urinary metabolites like VOCs, bisphenol, and triclosan. Participants were categorized by living floors: banjihas, first-fifth floors, and sixth floors or higher. Twenty-five children (4.3%) lived in banjihas, 311 (54.1%) on the first to fifth floor, and 239 (41.6%) on the sixth floor or above. Despite similar levels of allergen sensitization and urinary pollutant metabolite levels across all groups, banjiha dwellers showed significantly higher total airway resistance (adjusted &1: 0.633, 95%CI: 0.156, 1.109; P = 0.009) and a greater prevalence of elevated FeNO levels (> 35 ppb) (P = 0.033). These findings persisted after adjusting for critical factors like height, gender, BMI z-score, and birth conditions. Children in banjihas exhibit elevated airway resistance and FeNO levels independently of allergen sensitization or pollution exposure, underscoring the necessity for enhanced focus on their respiratory health in such living conditions.

Development of an automated, high-throughput assay to detect angiotensin AT2-receptor agonistic compounds by nitric oxide measurements in vitro

Angiotensin AT2-receptor (AT2R) agonists have shown a wide range of protective effects in many preclinical disease models. However, the availability of AT2R-agonists is very limited due to the lack of high-throughput assays for AT2R-agonist identification. Therefore, we aimed to design and validate an assay for high-throughput screening of AT2R-agonist candidates. The assay is based on nitric oxide (NO) release measurements in primary human aortic endothelial cells (HAEC), in AT2R-transfected CHO cells (AT2R-CHO) or in non-transfected CHO cells (Flp-CHO) using the fluorescent probe DAF-FM diacetate. It is run in 96-well plates and fluorescence signals are semi-automatically quantified. The assay was tested for sensitivity (recognition of true positive results), selectivity (recognition of true negative results), and reliability (by calculating the repeatability coefficient (RC)). The high-throughput, semi-automated method was proven suitable, as the NO-releasing agents C21, CGP42112A, angiotensin-(1−7) and acetylcholine significantly increased NO release from HAEC. The assay is sensitive and selective, since the established AT2R-agonists C21, CGP42112A and angiotensin II significantly increased NO release from AT2R-CHO cells, while the non-AT2R-agonists angiotensin-(1−7) and acetylcholine had no effect. Assay reliability was shown by high-throughput screening of a library comprised of 40 potential AT2R-agonists, of which 39 met our requirements for reliability (RC ≤ 20% different from RC for C21). Our newly developed high-throughput method for detection of AT2R-agonistic activity was proven to be sensitive, selective, and reliable. This method is suitable for the screening of potential AT2R-agonists in future drug development programs.

Device comparison study to measure nasal nitric oxide in relation to primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a genetic respiratory disease characterized by chronic cough, recurrent respiratory infections, and rhinosinusitis. The measurement of nasal nitric oxide (nNO) against resistance has been suggested as a sensitive screening method. However, current recommendations argue for the use of expensive, chemiluminescence devices to measure nNO. This study aimed to compare nNO measurement using three different devices in distinguishing PCD patients from healthy controls and cystic fibrosis (CF) patients and to evaluate their diagnostic precision. The study included 16 controls, 16 PCD patients, and 12 CF patients matched for age and sex. nNO measurements were performed using a chemiluminescence device (Eco Medics CLD 88sp), and two devices based on electrochemical sensors (Medisoft FeNO+ and NIOX Vero) following standardized guidelines. Correlation estimation, Bland–Altman, ROC curve, and one-way ANOVA were used to assess device differences and diagnostic performance. Significantly lower nNO output values were observed in PCD and CF patients compared to controls during exhalation against resistance. The correlation analysis showed high agreement among the three devices. ROC curve analysis demonstrated 100% sensitivity and specificity at different cut-off values for all devices in distinguishing PCD patients from controls (optimal cut-offs: EcoMedics 73, Medisoft 92 and NIOX 87 (nl min−1 )). Higher nNO output values were obtained with the Medisoft and NIOX devices as compared to the EcoMedics device, with a bias of−19 nl min−1 (95% CI: −73–35) and −21 nl min−1 (−73–31) accordingly. These findings indicate that all three tested devices can potentially serve as diagnostic tools for PCD if device specific cut-off values are used. This last-mentioned aspect warrants further studies and consideration in defining optimal cut-offs for individual device.

Measurements of methane and nitrous oxide in human breath and the development of UK scale emissions

Exhaled human breath can contain small, elevated concentrations of methane (CH4) and nitrous oxide (N2O), both of which contribute to global warming. These emissions from humans are not well understood and are rarely quantified in global greenhouse gas inventories. This study investigated emissions of CH4 and N2O in human breath from 104 volunteers in the UK population, to better understand what drives these emissions and to quantify national-scale estimates. A total of 328 breath samples were collected, and age, sex, dietary preference, and smoking habits were recorded for every participant. The percentage of methane producers (MPs) identified in this study was 31%. The percentage of MPs was higher in older age groups with 25% of people under the age of 30 classified as MPs compared to 40% in the 30+ age group. Females (38%) were more likely to be MPs than males (25%), though overall concentrations emitted from both MP groups were similar. All participants were found to emit N2O in breath, though none of the factors investigated explained the differences in emissions. Dietary preference was not found to affect CH4 or N2O emissions from breath in this study. We estimate a total emission of 1.04 (0.86–1.40) Gg of CH4 and 0.069 (0.066–0.072) Gg of N2O in human breath annually in the UK, the equivalent of 53.9 (47.8–60.0) Gg of CO2. In terms of magnitude, these values are approximately 0.05% and 0.1% of the total emissions of CH4 and N2O reported in the UK national greenhouse gas inventories.

Dietary inflammation index association with serum levels of nitric oxide, prostacyclin, and thromboxane B2 among prinzmetal angina patients and healthy persons

Background and aimThis study aimed to assess the association between dietary inflammation index with serum Nitric oxide, Prostacyclin, and Thromboxane B2 among Prinzmetal angina patients and healthy persons. Methods and resultsThis case-control study was conducted among 120 Prinzmetal angina patients and 120 healthy persons referred to the Ardabil Imam Khomeini Hospital between 2021 and 2022. Blood samples were gained from all study participants for measurement of serum Nitric oxide, Prostacyclin, and Thromboxane B2. The serum Nitric oxide in patients who had higher DII was less than in patients with less dietary inflammation index (β = −0.75 p = 0.02). The serum Prostacyclin level in patients with greater dietary inflammation index was 0.68 ng/ml less than in patients with less dietary inflammation index (β = −0.68 p = 0.04). The level of serum Thromboxane B2 had a positive association with dietary inflammation index (β = 0.81 p = 0.04). ConclusionIn Prinzmetal angina patients, more dietary inflammation index can increase the serum Thromboxane B2 and decrease the serum Nitric oxide and Prostacyclin. More clinical trial study is needed to confirm these results.

Association of inflammatory cytokines with obesity and pulmonary function testing.

The World Health Organization (WHO) reported that the prevalence of obesity in the Kingdom of Saudi Arabia (KSA) is 33.7% (women 39.5% and men 29.5%), respectively. The effects of obesity on airway inflammation and respiratory mechanics as well as the function of adipose tissue has a key role in the development of various lung diseases. Therefore, this study aimed to compare the level of cytokines between obese (BMI ≥ 30) and non-obese participants and to assess their association with BMI, airways inflammation and pulmonary function. One-hundred and seven non-smoking students (18-25 years of age) were recruited using convenience sampling technique for comparative cross-sectional study. Of them, 80 students were eligible and included in the analysis; 54 were non-obese (BMI<30) and 26 were obese (BMI ≥ 30). All the participants underwent anthropometric measurements, fractional exhaled nitric oxide (FeNO) measurement, spirometry and cytokines measurement (IL-6, IL-1β, GM-CSF, IL-7, IL-8 and IL-10). Measurements were compared between obese and non-obese groups. Then a correlation test was made between pro- and anti-inflammatory cytokines with BMI, pulmonary function test finding and FeNO. The prevalence of obesity was 32.5% in the study population. Levels of pro-inflammatory cytokine IL-6 levels was significantly higher in obese than non-obese participants (p = 0.044). The level of FeNO log was significantly higher in obese participants than non-obese (p = 0.002). The pro-inflammatory cytokine IL-6 showed positive correlation with BMI while GMCSF showed negative correlation with FVC (p<0.05). The levels of pro-inflammatory cytokine IL-6 was found to be significantly higher in obese participants than non-obese participants. Furthermore, it showed positive correlation with BMI whereas pro-inflammatory cytokine GMCSF showed negative correlation with FVC.

Pharmacological Evaluation of Anti-Diabetic Activity of Myricetin in Different Cell Lines

The aim of this research work was to perform pharmacological evaluation of Myricetin by using different cell lines. To check the short-term cytotoxic effect of Myricetin in HepG2 and L6 cells, a colorimetric based MTT assay was performed also the glucose utilization in both HepG2 and L6 cells was estimated in order to measure the in vitro anti-diabetic activity of Myricetin. For Lipid accumulation T3-L1 preadipocytes cells are used. For measurement of nitric oxide (NO) the RAW-264.7 cells are used. The alpha-amylase assay and alpha-glucosidase inhibition assay was performed to check if our drug is having effect in term of inhibiting α-amylase and α-glucosidase respectively. Western blot analysis was performed to check the expressions of iNOS protein in LPS treated RAW 264.7 cells before and after the exposure of Myricetin. The cytotoxicity data suggested that Myricetin displayed low level of cytotoxicity in HepG2 cells and in L6 myoblast cell lines. For glucose utilization experiment, it discovered that glucose uptake level was notably increase in HepG2 cells and in L6 myoblast cell lines with the increasing concentration of Myricetin. Myricetin increase lipid accumulation in 3T3-L1 preadipocytes and also inhibits nitric oxide production in RAW 264.7 cell lines. Research was found that Myricetin had no significant effect in order to alter the expression of alpha-amylase and alpha-glucosidase. Our research concludes that Myricetin can be used as a potent anti-diabetic agent.

Reduction of sewage sludge and N2O emissions by an Oxic Settling Anaerobic (OSA) process: The case study of Corleone (Italy) wastewater treatment plant

Biosolid management is becoming one of the most crucial issues for wastewater treatment plant (WWTP) operators. The application of the Oxic Settling Anaerobic (OSA) process allows the minimisation of excess sludge production. This study compares conventional activated sludge (CAS) and OSA layouts in a full-scale WWTP (namely, Corleone - Italy). Extensive monitoring campaigns were conducted to assess treatment performances regarding carbon and nutrient removal, greenhouse gas (GHG) emissions, excess sludge production, and biomass activity (by means of respirometric analysis). Results showed that the effluent quality consistently met the Italian discharge limits. However, with the implementation of the OSA process, there was a decrease in ammonium removal efficiency, which could be attributed to reduced nitrifier activity related to reduced biomass production and extended anaerobic conditions affecting the nitrification process. On the other hand, the OSA configuration significantly increased phosphorus removal, indicating a high phosphorus content in the resulting waste sludge. A worsening of the sludge settling properties was observed with the OSA configuration likely due to decreased EPS concentrations. The sludge production in the OSA configuration decreased by 17.3 % compared to CAS. Nitrous-oxide measurements did not show a variation between CAS and OSA configurations, confirming that the OSA process can be a suitable solution for reducing WWTP's carbon footprint.

Semidiurnal nonmigrating tides in low-latitude lower thermospheric NO: A climatology based on 20 years of Odin/SMR measurements

The Sub-Millimetre Radiometer (SMR) on board the Odin satellite provides almost 20 years of nitric oxide (NO) measurements in the mesosphere and lower thermosphere (MLT) at equatorial crossing local solar times (LSTs) of 6AM and 6PM. In this study, we use Odin/SMR observations to estimate how lower thermospheric NO mixing ratios at low latitudes are affected by solar nonmigrating tides. Most of the previous studies based on satellite data have focused on the signatures of diurnal tides in the MLT and above, while we concentrate here on nonmigrating semidiurnal tides. To study the contribution of these tides to NO mixing ratio variations, we average pairs of NO measurements along ascending and descending orbital tracks at 107 km altitude over latitudes between −40°and +40°. We consider monthly climatologies of these pair-averages and analyse residuals with respect to their zonal mean. In this way, it is possible to study the effect of nonmigrating even-numbered tidal components, albeit there is a non-tidal component arising largely from quasi-stationary planetary waves. Spectral wave amplitudes are extracted using a Fourier transform as function of (apparent) zonal wavenumber with a focus around −30°, −20°and 30°latitudes. From our analysis, it appears that the semidiurnal (apparent) zonal wavenumber 4 arising from the SW6 and SE2 tides is dominant close to the equator (e.g., at −20°), except during some boreal summer months (June, July, August). On the other hand, wave-1 plays a more prominent role at subtropical latitudes, especially in the southern hemisphere, where it surpasses wave-4 during 7 months (March and May-to-October) at −30°. There is little observational evidence to date documenting the presence of the semidiurnal nonmigrating tides in NO in the low-latitude MLT. Our results hence provide one of the first evidences of the climatological signature of these tides in NO, in an altitude range that remains poorly observed.

Evaluation of anti-inflammatory activity of kaurenol: Experimental evaluation and mechanistic insights.

Kaurenol, a diterpene alcohol found in Copaifera langsdorffii Desf. (known as "copaiba"), is historically used in traditional medicine for inflammatory conditions. This study aims to comprehensively assess the potential anti-inflammatory and antinociceptive properties of kaurenol. To this end, the following experiments were conducted to evaluated toxicity: locomotor performance and acute toxicity; nociception: acetic acid-induced writhing and formalin-induced antinociception; and anti-inflammatory activity: carrageenan and dextran-induced paw edema at 10, 20, and 40 mg/kg, and measurement of nitric oxide (NO), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) in macrophages at 1, 3, and 9 μg/ml. Kaurenol did not show significant locomotor changes, acute toxicity, and central analgesic activity in the first phase of formalin test at dosages tested. Kaurenol showed 53%, 64%, 64%, and 58% of inhibition in the acetic acid-induced writhing, second phase of formalin test, carrageenan and dextran-induced paw edema, respectively. The anti-inflammatory activity was associated with the regulation of NO release and probably with the regulation of mediators, such as serotonin and prostaglandin in vascular permeability, as well as by being associated with the regulation of IL-6 and IL-10. Kaurenol display anti-inflammatory activity but has no analgesic activity.

Diagnostic testing in people with primary ciliary dyskinesia: An international participatory study.

Diagnostic tests are important in primary ciliary dyskinesia (PCD), a rare disease, to confirm the diagnosis and characterize the disease. We compared diagnostic tests for PCD between countries worldwide, assessed whether people with PCD recall their tests, and identified factors associated with the use of tests. We used cross-sectional data from COVID-PCD-an international participatory cohort study collecting information directly from people with PCD. The baseline questionnaire inquired about tests used for PCD diagnosis. Using logistic regression, we investigated factors associated with measurement of nasal nitric oxide (nNO), biopsy for electron or video microscopy, and genetic testing. We included data from 747 participants (60% females) from 49 countries worldwide with median age 27 (interquartile range 12-44). Most (92%) reported diagnostic tests for PCD. Participants reported measurements of nNO (342; 49%), biopsy samples (561; 75%), and genetic tests (435; 58%). The reported use of individual tests, such as genetics, varied between countries from 38% in Switzerland to 68% in North America. Participant recall of test type also differed between countries with lowest recall in Switzerland. One-third (232; 36%) of participants reported all three tests (nNO, biopsy, and genetics). Recently diagnosed people reported more tests [nNO odds ratio (OR) 2.2, 95% Confidence Interval (CI) 1.5-3.2; biopsy OR 3.2, 95%CI 2.1-4.9; genetics OR 4.7, 95%CI 3.2-6.9] and those with situs abnormalities fewer tests (nNO OR 0.5, 95%CI 0.4-0.7; biopsy OR 0.5, 95%CI 0.4-0.8; genetics OR 0.7, 95%CI 0.5-0.94). Our results indicate PCD diagnostic testing differed widely around the world and many patients received incomplete diagnostic work-up based only on clinical features or single tests. People diagnosed long ago and those with situs abnormalities possibly benefit from supplementary testing to refine their diagnosis as a prerequisite for personalized medicine.

Simultaneous high-precision, high-frequency measurements of methane and nitrous oxide in surface seawater by cavity ring-down spectroscopy

An automated system was developed using commercially available Cavity Ring-Down Spectroscopy (CRDS) technology (Picarro LTD., G2508) which was interfaced to a custom-made system which automated the equilibration and analysis of seawater dissolved nitrous oxide (N2O) and methane (CH4). The combined system was deployed during two research cruises in the Atlantic Ocean, which combined covered 16,500 kms, one on a west to east transect between the United States and Europe at approximately 24°N, the second was a north to south transect which covered approximately 70° of latitude between the Tropic of Cancer and the Southern Ocean. Semi-continuous measurements using the CRDS (Approx. 73,000) were compared to discretely collected samples (n=156) which were analysed using gas chromatography (GC) with flame ionisation detection for CH4 and electron capture detection for N2O. Excellent agreement between the two approaches, though with an increase in analytical precision offered by CRDS compared to GC gives great confidence in the applicability of the CRDS system, whilst the significant (2 to 3 orders of magnitude) increase in measurement frequency offer an opportunity to greatly increase the number of dissolved N2O and CH4 data that are currently available. Whilst identifying a number of small-scale features, deployment during this study showed that whilst the surface of large areas of the Atlantic Ocean were in-balance with the overlying atmosphere with respect to N2O, the most of this region was offering a source of atmospheric CH4.