Nitric Oxide Concentration Research Articles

Effect of Whole-Body Cryotherapy on Oxidant-Antioxidant Imbalance in Women with Multiple Sclerosis.

The aim of the study was to investigate whether 20 whole-body cryotherapy treatments have an effect on oxidative-antioxidant imbalances in women with multiple sclerosis. Fifty women aged 30-55 were examined: study group-15 women with multiple sclerosis, subjected to whole-body cryotherapy; first control group-20 women with multiple sclerosis who did not receive cryotherapy intervention; second control group-15 healthy women who participated in cryotherapy treatments. Blood from the examined women was collected twice (before and after the series of 20 cryotherapy sessions). An insignificant increase in the total antioxidant capacity (study group: p = 0.706; second control group: p = 0.602) was observed after the whole-body cryotherapy intervention. After the series of cryotherapy sessions, the total oxidative status/total oxidative capacity value was insignificantly decreased among the multiple sclerosis patients (decrease by 14.03%, p = 0.495). In women with multiple sclerosis, no significant cryotherapy impact was demonstrated on changes in the oxidant-antioxidant imbalance or concentrations of nitric oxide, uric acid, or matrix metalloproteinase-9.

Assessment of CI Engine Performance Utilizing Palm Oil Biodiesel Blend

Experiment was explores vegetable oils as potential future fuels for internal combustion engines, particularly compression ignition engines designed for diesel. However, these oils have distinct properties from diesel, requiring modifications for direct use. Integration approaches include adjusting oil properties or adapting engines. Commonly, transesterification aligns oil properties, but using biodiesel often affects engine performance. In this study palm oil biodiesel as a diesel substitute, evaluating engine performance and emissions. In a short-term test, engine performance and emission traits by employing biodiesel blends of 0, 20, and 50 % with diesel at full load. Findings indicated that B20 and B50 exhibited 2.40% and 3.88% lower brake power than pure diesel. Volumetric efficiency percentages were 82.44 for B20, 81.64 for B50, and 82.93 for diesel. Notably, B20 and B50 showed 9.35% and 10.70 % decreased brake thermal efficiency compared to diesel. Interestingly, B20 and B50 displayed 1.09 and 2.44 % higher mechanical efficiency than diesel. Exhaust gas temperature was notably elevated in B20 and B50 blends. Nitric oxide concentrations were 98.74 ppm for diesel, 105.48 ppm for B20, and 111.78 ppm for B50. Carbon dioxide levels decreased by 4.14% for B20 and 7.86% for B50 relative to diesel. Carbon monoxide concentrations were 0.082% for B20 and 0.080% for B50, in contrast to diesel's 0.10%.

Oxidative stress associated with proteomic and fatty acid profiles of sperm from Nellore bulls at rest†.

Sexual rest is a transient condition, which compromises conception rates, characterized by large volumes of ejaculate with high percentages of dead sperm observed in bulls. The biochemical mechanisms leading to this ejaculate pattern are not fully understood. Six adult resting Nellore bulls were submitted to Breeding Soundness Evaluation by four consecutive semen collections through the electroejaculation method during a 30min period. Each ejaculate had its semen phenotypic parameters; morphology and physical aspects were evaluated. To assess enzymatic activity (superoxide dismutase, catalase, and glutathione S-transferase), lipid peroxidation (concentrations of malondialdehyde and nitric oxide), fatty acid, and proteomic profile aliquots of spermatozoa from the first and fourth ejaculates were used. All sperm parameters differed between the first and fourth ejaculates. Spermatozoa from the first ejaculate showed lower enzymatic activity and a higher concentration of lipid peroxidation markers. Among the 19 identified fatty acids, 52.7% are polyunsaturated. Relative abundance analysis showed that C12:0 and C18:0 fatty acids differed between the first and fourth ejaculates, being the fourth ejaculate richer in spermatozoa. The proteomics analysis identified a total of 974 proteins in both sample groups (first and fourth ejaculates). The majority of identified proteins are related to cellular processes and signaling. Quantitative proteomics showed 36 differentially abundant proteins, 6 up-regulated proteins in the first ejaculate, and 30 up-regulated proteins in the fourth ejaculate. Spermatozoa from bulls at sexual rest have less antioxidant capacity, causing changes in their fatty acid composition and protein profile, which generates the observed sperm pattern and lower fertilization capacity.

PROFILING OF PHYLLANTHUS AMARUS PHYTOCHEMICAL CONSTITUENTS AND EVALUATION OF ASSOCIATED ANTIMALARIAL ACTIVITY AND ANTIOXIDANT POTENTIAL IN EXPERIMENTAL MICE

The failing curative ability of antimalarials has prompted an open discussion for the use of antioxidants in combination with antimalarials for effective chemotherapy. This study profiled the phytochemical constituents of Phyllanthus amarus and evaluated their antimalarial and antioxidant activities. Phytochemical screening, antimalarial and acute oral toxicity were determined according to standard procedures. Blood antioxidant activity was assessed by measuring antioxidant enzymes and nitric oxide (NO), concentrations of malarial infected mice treated with P. amarus phytochemicals. Alkaloids, the most abundant phytochemical, demonstrated the highest malarial parasite chemosuppression and greatly improved NO concentration in infected mice. However, flavonoid extract demonstrated the highest antioxidant potential with most significant impact on catalase and malondialdehyde activity. Alkaloid may function as antimalarial agent by inhibiting haem polymerization to hemozoin as judged by its increased effect on NO concentration which bears an reverse relationship with hemozoin.

Synthesis and secretion of Nerve Growth Factor is regulated by Nitric Oxide in bladder cells in vitro under a hyperglycemic environment

Urine samples of female patients with overactive bladder (OAB) are characterized by low levels of nerve growth factor (NGF) and elevated concentrations of nitric oxide (NO) compared to healthy controls. We therefore examined how NO might regulate NGF synthesis using rat bladder smooth muscle (SMCs) and urothelial (UROs) cells in culture. In UROs, incubation in hyperglycemic conditions to mimic insulin insensitivity present in the OAB cohort increased secretion of NO and concomitantly decreased NGF, except when the NO synthase inhibitor, l-NAME (1 mM) was present. Sodium nitroprusside (SNP) (300 μM, 24 h), a NO generator, decreased NGF levels and decreased cyclic GMP (cGMP) content, a process validated by the cGMP synthase inhibitor ODQ (100 μM). Alternatively, SNP increased mRNA of both NGF and matrix metalloproteinase-9 (MMP-9). MMP-9 knockout of UROs by Crispr-Cas9 potently decreased the effect of SNP on NGF, implying a dependent role of NO on MMP-9. On the other hand, matrix metalloproteinase-7 (MMP-7) activity was increased by SNP, which taken together with increase in NGF mRNA, suggests a compensatory mechanism. In SMCs, hyperglycemic conditions had the same effect on extracellular content of NO and NGF than in UROs. SNP also decreased NGF secretion but increased cGMP content. Stable permeable analogs of cGMP 8-(4-Chlorophenylthio)-cGMP (1 mM) and N2,2′-O-Dibutyryl-cGMP (3 mM) inhibited NGF release. NGF and MMP-9 mRNA expression was unchanged by SNP. Deletion of MMP-9 in SMCs by Crispr-Cas9 did not alter the effect of SNP. Finally, SNP decreased MMP-7 activity, diminishing the conversion of proNGF to NGF. These results demonstrate that enhanced NO secretion triggered by high glucose decreases NGF secretion through pathways unique for each cell type that involve cGMP and proteases MMP-7 and MMP-9. These results might help to explain our observations from the urine from patients with OAB associated with metabolic syndrome.

Influence of Atherosclerotic Risk Factors on the Effectiveness of Therapeutic Ultrasound Cavitation for Flow Augmentation

Shear created by inertial cavitation of microbubbles by ultrasound augments limb and myocardial perfusion and can reverse tissue ischemia. Our aim was to determine whether this therapeutic bioeffect is attenuated by atherosclerotic risk factors that are known to impair shear-mediated vasodilation and adversely affect microvascular reactivity. In mice, lipid-stabilized decafluorobutane microbubbles (2×108) were administered intravenously while exposing a proximal hind limb to ultrasound (1.3MHz, 1.3 mechanical index, pulsing interval 5seconds) for 10 minutes. Murine strains included wild-type mice and severely hyperlipidemic mice at 15, 35, or 52 weeks of age as a model of aging and elevated cholesterol, and obese db/db mice (≈15weeks) with severe insulin resistance. Quantitative contrast-enhanced ultrasound perfusion imaging was performed to assess microvascular perfusion in the control and ultrasound-exposed limb. An in situ electrochemical probe and invivo biophotonic imaging were used to assess limb nitric oxide (NO) and adenosine triphosphosphate concentrations, respectively. Microvascular perfusion was significantly increased by several fold in the cavitation-exposed limb versus control limb for all murine strains and ages (P<.001). In wild-type and hyperlipidemic mice, hyperemia from cavitation was attenuated in the 2 older age groups (P<.01). In young mice (15weeks), perfusion in cavitation-exposed muscle was less in both the hyperlipidemic mice and the obese db/db mice compared with corresponding wild-type mice. Using young hyperlipidemic mice as a model for flow impairment, limb NO production after cavitation was reduced but adenosine triphosphosphate production was unaltered when compared with age-matched wild-type mice. In mice, ultrasound cavitation of microbubbles increases limb perfusion by several fold even in the presence of traditional atherosclerotic risk factors. However, older age, hyperlipidemia, and insulin resistance modestly attenuate the degree of flow augmentation, which could impact the degree of flow response in current clinical trials in patients with critical limb ischemia.

Association between endothelial nitric oxide synthase (eNOS) gene variants and nitric oxide production in preeclampsia: a case–control study in Ghana

Evidence suggests that a major cause of PE is endothelial dysfunction emanating from the reduced bioavailability of Nitric oxide (NO). Variants of endothelial nitric oxide synthase (eNOS) gene may lead to decreased NO levels. We explored the association between eNOS gene variants and nitric oxide levels among preeclamptic women in the Ghanaian population. This case–control study included 75 preeclamptic women and 75 healthy normotensive pregnant women attending antenatal care at the Nkawie-Toase Government Hospital, Ghana. A well-structured questionnaire was used to collect socio-demographic, obstetric and clinical data. Blood was obtained for DNA extraction; the gene variants were determined using PCR and RFLP. Preeclamptic women had significantly lower NO concentration compared to the normotensives (p < 0.0001) and was significantly different between VNTR variants (p < 0.0001). A significant difference in VNTR intron 4 distribution was also observed between the preeclamptic and normotensive women with 4c4c” (12.0%) and “4a4c” (1.3%) genotypes found predominantly in preeclamptic women (p < 0.0001). There was significantly higher distribution of “TC” genotype in preeclamptic women (44.0%) compared to normotensives (22.7%) (p = 0.019). However, possessing “4a4b” (cOR: 0.17, 95% CI 0.04–0.64) and “4b4b” (cOR: 0.09, 95% CI 0.02–0.38) significantly decreased the likelihood of experiencing preeclampsia by 83% and 91% respectively. Nitric oxide is reduced in preeclamptic women. NO levels in preeclampsia are altered by VNTR intron 4 variants but not T786C variants. Possessing VNTR intron 4 “4b” allele decreases the risk of PE while the “4c” allele increases the risk of PE. There is the need for eNOS variant screening and nitric oxide estimation among pregnant women for early prediction of women at risk of preeclampsia.

Spatiotemporal variations and dominated environmental parameters of nitrous oxide (N2O) concentrations from cascade reservoirs in southwest China.

Anthropogenic activity has caused rivers and reservoirs to become sources of nitrous oxide (N2O), which is thought to play an important role in global climate change. There are thermal and DO stratification in deep-water reservoirs with long hydraulic retention time, which change N2O production mechanism compared with shallow-water reservoirs. To promote our understanding of the relationship of N2O production in reservoirs at different depths, spatiotemporal variations in water environmental factors and N2O from cascade reservoirs of Chaishitan (CST), Longtan (LT), Yantan (YT) and Dahua (DH) reservoirs in the Zhujiang River were detected, and the LT and YT reservoirs were compared as representatives of deep-water and shallow-water reservoirs in April and July 2019. The average N2O concentrations in the LT and YT reservoirs were 22.82 ± 2.21 and 21.55 ± 1.65nmol L-1, respectively. During spring and summer, the WT (water temperature) and DO (dissolved oxygen) concentrations in the YT reservoir were well mixed. In contrast, the LT reservoir, as a deep-water reservoir, had thermal and DO stratifications in both the shallow and middle water, especially in the summer when the solar radiation intensity was high. During summer stratification, the DO concentration in the LT reservoir showed obvious spatial variation, ranging from 1.23 to 9.84mg L-1, while the DO concentration in the YT reservoir showed very little variation, ranging from 6.45 to 7.09mg L-1. Structural equation modeling results showed that NH4+ was the main determinant of the N2O concentration in the YT reservoir, and DO was the most influential factor of the N2O concentration in the LT reservoir. These results suggest significant variations in the factors influencing N2O concentration among reservoirs. Additionally, the mechanisms of N2O production differ between deep-water and shallow-water reservoirs. This study highlights the spatio-temporal variations and influential factors contributing to N2O concentration. Furthermore, it discusses the production mechanisms of N2O in different types of reservoirs. These findings contribute to our understanding of N2O distribution in hydropower systems and provide valuable data for the management of hydropower facilities and research on greenhouse gas emissions.

Soluble guanylate cyclase mediates the relaxation of healthy and inflamed bladder smooth muscle by aqueous nitric oxide.

Introduction: Due to its chemical properties, functional responses to nitric oxide (NO) are often difficult to examine. In the present study, we established a method to produce NO in an aqueous solution and validated its capacity to evoke functional responses in isolated rat bladders. Furthermore, we compared the NO responses to the commonly used NO donor sodium nitroprusside (SNP). We also investigated the impact of ongoing inflammation on the involvement of soluble guanylate cyclase (sGC) dependent signaling in NO relaxation. Methods: A setup to produce an aqueous NO solution was established, allowing the production of an aqueous solution containing a calculated NO concentration of 2mM. Sixty male Sprague-Dawley rats received either no treatment (controls) or cyclophosphamide (CYP; 100mg*kg-1 i.p., 60h prior to the experiment) to induce experimental cystitis. Bladder strip preparations were mounted in organ baths and studied at basal tension or pre-contracted with methacholine (3μM). Aqueous NO solution (40-400μL; 2mM corresponding to 4-40μM) or SNP (1-1,000μM) was added cumulatively in increasing concentrations. Relaxation to aqueous NO was also studied in the presence of the sGC inhibitor ODQ (0.25-25μM). The expression of sGC was investigated by immunohistochemical analysis. Results: The NO solution caused functional relaxations in both controls and inflamed bladder preparations. NO-induced relaxations were significantly greater in inflamed bladder strips at basal tension, whereas no differences were seen in methacholine pre-contracted strips. In the presence of the sGC inhibitor ODQ in a high concentration, the NO-evoked relaxations were abolished in both control and inflamed preparations. At a lower concentration of ODQ, only NO relaxations in inflamed preparations were attenuated. Immunohistochemical analysis showed that sGC was expressed in the detrusor and mucosa, with a significantly lower expression in the inflamed detrusor. Conclusion: In the present study, we found that aqueous NO solution induces relaxation of the rat detrusor by activating soluble guanylate cyclase in both control and inflamed bladder strips. Induction of inflammation conceivably leads to decreased sGC expression in the detrusor, which may explain the different susceptibility towards inhibition of sGC in inflamed versus control tissue. The use of an aqueous NO solution should be further considered as a valuable complement to the pharmacological tools currently used.

Effects of nitric oxide on the phytoremediation of swine wastewater by Pistia stratiotes under copper stress

Nitric oxide (NO) is widely present in wastewater. As a signaling molecule, NO influences many aspects of phytoremediation, especially in response to heavy metal stress. The current understanding of the impact of NO on the tolerance of Pistia stratiotes and other plants to Cu2+ in swine wastewater is limited. This study aimed to investigate the impact of NO on the physiological response of Pistia stratiotes and its efficacy in removing pollutants from swine wastewater under varying concentrations of Cu2+ ranging from 1~4 mg/L. The findings showed that NO treatment reduced copper stress at 2~4 mg/L Cu2+ while increasing oxidative stress at 1 mg/L Cu2+. According to an analysis of physiological parameters and copper concentrations, the results found a significant correlation between increased copper tolerance and elevated levels of antioxidants and transport coefficients. The morphology of copper and the results of the principal component analysis indicate that NO facilitated the humification process of the dissolved organic matter. The investigation found that the removal efficiencies of NH3–N, NO3–N, and total phosphorus in NO treatment were enhanced to 95.76%, 88.72%, and 91.89%, respectively. Collectively, it was determined that NO is a regulator of phytoremediation to copper in wastewater via promoting antioxidative, copper transport, DOM bound, nutrients uptake, thus adequate amount could improve the tolerance of Pistia stratiotes to Cu2+. This study is expected to provide a theoretical basis for rationally regulating NO concentration and effectively improving the removal efficiency of copper in swine wastewater.

Effect of Resistance Training with Blood Flow Restriction on Sitruin-1, Visfatin, and Nitric Oxide Levels in Elite Male Athletes Following Anterior Cruciate Ligament Reconstruction

Background and Aims Blood flow restriction (BFR) training has been suggested as an effective method to improve muscle hypertrophy and for rehabilitation. The present study aims to investigate the effect of resistance training (RT) with BFR on serum levels of sirtuin-1 (SIRT-1), visfatin, and nitric oxide (NO) in elite male athletes after anterior cruciate ligament (ACL) reconstruction. Methods Twenty elite male athletes voluntarily participated in the study and were randomly divided into two groups of RT-BFR (n=10) and RT (n=10). Subjects in both groups participated in 12 weeks of RT at an intensity of 30-70% of 10-repetition maximum (2-4 sets). The subjects in the RT-BFR group performed resistance training by placing a blood pressure cuff in the upper thigh with a pressure of 120-180 mm Hg. Blood samples were collected before and 48 hours after the last training session to measure serum levels of blood markers. Data analysis was done by the analysis of covariance (ANCOVA) and paired t-test. P&lt;0.05 was considered statistically significant. Results Twelve weeks of RT-BFR significantly increased serum levels of SIRT-1 (P&lt;0.001(, visfatin (P=0.02), and NO (P=0.01) in the post-test phase, compared to the pre-test phase. Furthermore, the between-group analysis results showed that RT-BFR significantly increased serum levels of SIRT-1 (P&lt;0.001) and NO (P=0.002) compared to the RT group. Conclusion The RT combined with BFR can increase the serum concentrations of SIRT-1 and NO in elite athletes after ACL reconstruction, compared to the RT alone

Electrochemically-mediated reactive separation of nitric oxide into nitrate using iron chelate

Valorization of nitric oxide is a promising solution for addressing the environmental and resource issues related to the nitrogen cycle. However, low concentrations of nitric oxide combined with impurities in exhaust streams limit its potential, and it requires extensive energy to produce high-purity nitric oxide. Here, we propose a synergistic reactive separation system that combines iron-chelate selective absorption with an electrochemical reaction to convert nitric oxide to nitrate. Among the iron-based chelates tested, EDTA was found to be the most effective in capturing gas-phase nitric oxide. Direct electrochemical oxidation of Fe-EDTA-NO solution exhibited Faradaic efficiency and a partial current density toward nitrate of 70% and 30.1 mA cm−2 at 2.2 V vs RHE and pH 7, resulting in a 43-fold enhancement of nitrate partial current density and a 2-fold improvement in Faradaic efficiency compared to simple purging without selective absorbent. Nitrate was then selectively recovered from the Fe-EDTA system using simple polarity reversal following electrooxidation with a separation factor of 13 over background sulfate. This study offers a new approach to gas-phase NO remediation and valorization using an electrified means.

Effects of dietary vitamin E supplementation on growth performance, slaughter performance, antioxidant capacity and meat quality characteristics of finishing bulls

This study was conducted to investigate the effects of dietary supplementation of vitamin E (VE) on growth performance, slaughter performance, antioxidant capacity and meat quality characteristics of finishing bulls. Twenty Yanbian cattle (bulls) with initial body weight (BW) 485 ± 42 kg were randomly divided into two groups (control and treatment groups) and participated in a100-day finishing trial. The control group (CON) was fed a basal diet (total mixed ration, TMR). The treatment group was fed a basal diet supplemented with VE (provided as α-tocopherol acetate, 700 IU/bull/day). VE supplementation significantly increased the average daily gain (ADG) of finishing bulls, the beef marbling score, meat color parameters (a* [redness]), intramuscular fat content, the concentration of catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), VE and matrix metalloproteinases (MMP-13) in the serum and muscle tissue (P < 0.05). VE supplementation significantly decreased drip loss and cooking loss of the beef, the concentration of nitric oxide (NO) in the serum and muscle tissue, the concentration of malondialdehyde in the muscle tissue (P < 0.05), and tended to decrease the feed: gain (P = 0.077) and shear force (P = 0.062) of the beef. In conclusion, VE supplementation can improve the meat quality parameters of finishing bulls, especially the improvement of beef tenderness. The improvement of beef tenderness by VE supplementation may be related to the increase of MMPs concentration, and a potential mechanism for the secretion of MMPs by VE supplementation may be related to its antioxidant capacity.

Influence of different LED wavelengths on retinal melatonin levels - A rodent study

BackgroundRetinal melatonin is crucial for neuroprotection. Exposure to light-emitting diodes (LEDs) affects retinal neurons, possibly influencing retinal melatonin levels. Hence, we aimed to quantify the retinal melatonin level with different LED wavelengths. MethodA total of 24 Sprague Dawley (SD) male rats were divided into four groups (n = 6 in each group) as normal controls (NC), blue light (BL), white light (WL), and yellow light (YL). The rats in the experimental groups were exposed to different wavelengths of LEDs for 28 days (12:12 h light-dark cycle) with uniform illumination of 450–500 lx. Following exposure, the rats were subjected to behavioral tests such as passive avoidance and elevated plus maze tests. Following the behavior tests, the rats were sacrificed, eyes were enucleated, and retinal tissue was stored at −80 °C. The homogenized retina was used for reactive oxygen species (ROS) and melatonin quantification using an enzyme-linked immunosorbent assay (ELISA) kit. ResultsPassive avoidance test revealed a significant difference across the groups (p < 0.0004). The BL exposure group demonstrated increased latency to enter the dark compartment (DC) and impaired motor memory. The elevated plus maze test revealed a significant difference across all the groups (p < 0.012), where the time spent in the closed arm was greater in the BL exposure group. Comparison of ROS levels revealed a significant difference across the groups (p < 0.0001), with increased nitric oxide concentrations in the experimental groups. Melatonin levels were significantly decreased in the light exposure groups (p < 0.0001) compared to the NC group. ConclusionCumulative exposure to different LED wavelengths resulted in increased anxiety with impaired motor activity. This was also complemented by the addition of oxidative stress leading to decreased melatonin levels in the retina, which might trigger retinal neuronal damage.

Design, Synthesis, and Biological Evaluation of Esculetin-Furoxan-DEAC Ternary Hybrids for Anti-Triple Negative Breast Cancer.

Twelve new hybrid compounds of Esculetin with nitric oxide (NO) donors and/or mitochondrial targeting groups were designed, synthesized, and evaluated for their anti-tumor activity and mechanism in vitro and in vivo. Notably, the most potent compound A11 exhibited nanomolar antiproliferative activity on triple-negative breast cancer (TNBC) MDA-MB-231 cells (IC50 = 8 nM) with a strikingly selective inhibitory effect. The mechanism of A11 involves targeting MDA-MB-231 cells' mitochondria, releasing a high NO concentration, and increasing the expression of cyclophilin D (CypD), leading to increased reactive oxygen species (ROS) and triggering cancer cell apoptosis. Additionally, A11 could arrest the cell cycle at the G2/M phase to achieve anti-tumor effects. Moreover, A11 demonstrated a superior TNBC inhibition rate and diminished toxicity relative to doxorubicin (DOX) in vivo. In summary, A11 serves as a noteworthy contender for TNBC treatment with high potency and minimal toxicity.

Alveolar nitric oxide concentration has a potential value in the diagnosis and differential diagnosis of interstitial lung diseases

To investigate the value of exhaled nitric oxide (eNO) in the diagnosis and differential diagnosis of interstitial lung disease (ILD). This study was conducted among 45 patients with interstitial lung disease, including 18 with connective tissue disease-related ILD (CTD-ILD) and 27 with non-CTD-ILD, with 68 healthy subjects as the control group. According to European Respiratory Association Guidelines, alveolar nitric oxide (CaNO) concentration and fractional exhaled nitric oxide (FeNO) level were measured at the flow rates of 50 and 200 mL/s. The predictive level of CaNO was analyzed using receiver-operating characteristic curve (ROC), and the correlations between CaNO and pulmonary function indicators were examined in the patients with ILD. CaNO, FeNO50, and FeNO200 levels were significantly higher in patients with ILD than in the healthy controls. Logistic regression analysis showed that lowered levels of CaNO and FeNO200 were risk factors for ILD. ROC curve analysis showed that the area under the curve (AUC) of CaNO combined with FeNO200 was 0.829 (95% CI: 0.752-0.906) for the diagnosis of ILD. In patients with ILD, CaNO levels were negatively correlated with DLCO%pred (r=-0.471, P < 0.05). Subgroup comparison showed a significantly higher CaNO level in CTD-ILD group than in non-CTD-ILD group. The AUC for CaNO to discriminate CTD-ILD from non-CTD-ILD was 0.725 (95% CI: 0.576 to 0.875). CaNO has a potential value in the diagnosis of ILD and differential diagnosis of CTD-ILD.

L-Aminoguanidine Induces Imbalance of ROS/RNS Homeostasis and Polyamine Catabolism of Tomato Roots after Short-Term Salt Exposure.

Polyamine (PA) catabolism mediated by amine oxidases is an important process involved in fine-tuning PA homeostasis and related mechanisms during salt stress. The significance of these amine oxidases in short-term responses to salt stress is, however, not well understood. In the present study, the effects of L-aminoguanidine (AG) on tomato roots treated with short-term salt stress induced by NaCl were studied. AG is usually used as a copper amine oxidase (CuAO or DAO) inhibitor. In our study, other alterations of PA catabolism, such as reduced polyamine oxidase (PAO), were also observed in AG-treated plants. Salt stress led to an increase in the reactive oxygen and nitrogen species in tomato root apices, evidenced by in situ fluorescent staining and an increase in free PA levels. Such alterations were alleviated by AG treatment, showing the possible antioxidant effect of AG in tomato roots exposed to salt stress. PA catabolic enzyme activities decreased, while the imbalance of hydrogen peroxide (H2O2), nitric oxide (NO), and hydrogen sulfide (H2S) concentrations displayed a dependence on stress intensity. These changes suggest that AG-mediated inhibition could dramatically rearrange PA catabolism and related reactive species backgrounds, especially the NO-related mechanisms. More studies are, however, needed to decipher the precise mode of action of AG in plants exposed to stress treatments.

Oral and nasal provocation test in chicken egg allergy—case report

IntroductionAllergy to chicken egg protein is a common form of food allergy. The most common clinical presentation includes gastrointestinal, skin, and respiratory symptoms. Differential diagnosis, including provocative tests, is critical in diagnosis.Case descriptionWe present a case of a 21-year-old patient with egg allergy, who underwent a double-blind food provocation test with placebo (evaluating subjective complaints from the gastrointestinal tract) and a titrated nasal provocation test using dry chicken egg content. We assessed the response of the nasal mucosa in the provocation test using the visual analogue scale (VAS), acoustic and optical rhinometry, as well as measurements of nitric oxide concentration in the exhaled air. During the provocation test, we measured the changes in the transverse section of the nasal passages, which were accompanied by subjective complaints measured with the VAS scale, using objective techniques. In the nasal provocation test with a dose of 20 µg of chicken egg protein, we observed an increase in the reactivity of the nasal mucosa and a decrease in the level of nitric oxide in the exhaled air from the upper airways (920 ppb before the provocation test and up to 867 ppb during the early stage of the allergic reaction). During the provocation tests, we recorded typical symptoms associated with the early stage of the allergic reaction; including nasal obstruction (1.2 cm), leakage of watery discharge (0.8 cm) in the food test, and itchy nose (1.1 cm) in the food test vs. the nasal test: 4.6, 2.8, and 3.5 cm, respectively.ConclusionsThe nasal mucosa provides convenient conditions for evaluation of the severity of allergy to common food allergens, including chicken egg allergens.

Mound architecture and season affect concentrations of CO2, CH4 and N2O in nests of African fungus‐growing termites

Abstract Termites are a significant natural source of greenhouse gases (GHGs), but quantifying emissions especially from large termite mounds is problematic as they rarely fit in measurement chambers. Predicting fluxes based on internal and atmospheric concentrations could provide an indirect way to assess mound emissions, but developing such models necessitates better understanding of the concentration levels and their variance. We used gas chromatography to measure carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) concentrations within nests of two co‐occurring species of fungus‐growing termites in both dry and wet seasons in Kenya, with termite Macrotermes michaelseni building mounds with a closed and Macrotermes subhyalinus with an open ventilation system. Gas concentrations were 3–100 times higher in mounds than the global averages in atmosphere, implying that termite mounds are sources of all three GHGs. Carbon dioxide concentrations were higher in closed than in open mounds. Methane concentrations remained constant in open mounds, whereas closed mounds exhibited considerable variation between nests and across seasons. Concentrations of both CH4 and N2O correlated positively with mound volume during the wet season, whereas interactions with mound size were not observed in CO2 concentrations or during the driest sampling period. These findings underline that among fungus‐growing termites, mound size, ventilation type and precipitation affect nest gas concentrations and with this likely the magnitude of mound GHG emissions. Potential reasons behind the observed relationships are discussed, including differences in population size, biomass of fungus gardens and CH4 oxidation.

N-Nitrosation Based Fluorescence Turn-On Nitric Oxide Probe: Kinetic and Cell Imaging Studies.

Nitric oxide (NO) is a ubiquitous messenger molecule playing a key role in various physiological and pathological processes. However, producing a selective turn-on fluorescence response to NO is a challenging task due to (a) the very short half-life of NO (typically in the range of 0.1-10 s) in the biological milieu and (b) false positive responses to reactive carbonyl species (RCS) (e.g., dehydroascorbic acid and methylglyoxal etc.) and some other reactive oxygen/nitrogen species (ROS/RNS), especially with o-phenylenediamine (OPD) based fluorosensors. To avoid these limitations, NO sensors should be designed in such a way that they react spontaneously with NO to give turn-on response within the time frame of t1/2 (typically in the range of 0.1-10 s) of NO and λem in the visible wavelength along with good cell permeability to achieve biocompatibility. With these views in mind, a N-nitrosation based fluorescent sensor, NDAQ, has been developed that is highly selective to NO with ∼27-fold fluorescence enhancement at λem = 542 nm with high sensitivity (LOD = 7 ± 0.4 nM) and shorter response time, eliminating the interference of other reactive species (RCS/ROS/RNS). Furthermore, all the photophysical studies with NDAQ have been performed in 98% aqueous medium at physiological pH, indicating its good stability under physiological conditions. The kinetic assay illustrates the second-order dependency with respect to NO concentration and first-order dependency with respect to NDAQ concentration. The biological studies reveal the successful application of the probe to track both endogenous and exogenous NO in living organisms.