Utilizing plasma-generated N2O5 gas from atmospheric air as a novel gaseous nitrogen source for plants

Fixing atmospheric nitrogen for use as fertilizer is a crucial process in promoting plant growth and enhancing crop yields in agricultural production. Currently, the chemical production of nitrogen fertilizer from atmospheric N2 relies on the energy-intensive Haber-Bosch process. Therefore, developing a low-cost and easily applicable method for fixing nitrogen from the air would provide a beneficial alternative. In this study, we tested the utilization of dinitrogen pentoxide (N2O5) gas, generated from oxygen and nitrogen present in ambient air with the help of a portable plasma device, as a nitrogen source for the model plant Arabidopsis thaliana. Nitrogen-deficient plants supplied with medium treated with N2O5, were able to overcome nitrogen deficiency, similar to those provided with medium containing a conventional nitrogen source. However, prolonged direct exposure of plants to N2O5 gas adversely affected their growth. Short-time exposure of plants to N2O5 gas mitigated its toxicity and was able to support growth. Moreover, when the exposure of N2O5 and the contact with plants were physically separated, plants cultured under nitrogen deficiency were able to grow. This study shows that N2O5 gas generated from atmospheric nitrogen can be used as an effective nutrient for plants, indicating its potential to serve as an alternative nitrogen fertilization method for promoting plant growth.

Chronic total occlusion (CTO) revascularization a comparison from Japanese and European expert CTO operators registries

Background

Development of different strategies and devices improved CTO revascularization. However, technical and procedural success might be influenced by several factors including geographical expertise.

Methods

A total of 4412 CTO coronary treated lesions (Japan 1531 Europe 2881) (mean age 64.5±10.7, male 85.2%, JCTO score 2.09±1.24) were analyzed in European and Japanese registries during the year 2016. The primary endpoint was to assess technical success rate of CTO-PCI cases and procedural outcomes.

Results

Primary Antegrade approach and success rate were 71.5% and 90.8% respectively in Japan while 77.0% and 94.1%, respectively in Europe, (p<0001). Primary Retrograde approach and success rate were 28.5% and 84.0% respectively in Japan, while 22.6% and 69.2%, in Europe (p<0001). There were no differences in technical success rate between Japan and Europe (89.9% vs 88.5%, p=0.13). Procedural time was higher in Japan than in Europe 156.3±1.8 vs 107.1±1.3 mins (p<0.001), but contrast media volume resulted the opposite 209.6±3.2 ml vs 267.5±2.4 ml, (p<0.001). Procedural complications were higher in Japan than Europe (death: 0.4% vs 0.07%, p=0.024, myocardial infarction: 1.2% vs 0.57% p=0.045, coronary artery occlusion: 0.26% vs 0.07% p=0.026, coronary perforation: 4.22% vs 3.04% p=0.045). A multivariate analysis showed that independent predictors of failed procedure were both for Japan and Europe unsuccessful retrograde crossing channel, severe lesion calcification and occlusion length>20mm.

Conclusions

Technical success rate was similar between Japan and Europe, but more retrograde approach was common in Japan. Unsuccessful retrograde crossing channel, severe lesion calcification and occlusion length>20mm were independent predictors of failed procedures for both countries. Procedural complications were higher in Japan probably because of longer procedural time and higher frequency of retrograde approach.

Funding Acknowledgement

Type of funding source: None

Two molecular forms of plasma adrenomedullin during tilt test in healthy subjects

There is accumulating evidence suggesting that adrenomedullin (AM) may participate in the regulation of circulatory homeostasis and pathophysiology of cardiovascular disease. A recent study revealed that two molecular forms of AM, an active form of mature AM (AM-m) and an intermediate inactive form of glycine-extended AM (AM-Gly), circulate in human plasma. The object of the present study was to evaluate the effect of orthostasis on a time course of two molecular forms of plasma AM and to compare them with the behavior of other vasoactive hormones. Twelve healthy male volunteers were studied. The experimental protocol consisted of 20 min of supine rest, tilting at 70 degrees for 20 min, and then 20 min of supine rest. Blood pressure and heart rate were measured every minute. Blood samples were obtained before, at 2 and 18 min during the tilt test, and 2 and 18 min after the test for the measurements of vasoacting hormones and hematocrit. Blood pressure and heart rate were slightly increased earlier during tilting and then remained elevated until the end of the test. The increase in heart rate and blood pressure returned to normal levels early after the tilt test. Plasma epinephrine and norepinephrine significantly increased during the tilt test. These hormones returned to normal levels 18 min after the test. The plasma renin activity, antidiuretic hormone and dopamine were also increased by the end of the tilt test, whereas plasma atrial natriuretic peptide was significantly decreased after the tilt test. Hematocrit increased slightly in the early phase of the tilt test and was further increased by the end of the test. In contrast, plasma AM-Gly or AM-m did not change during the tilt test or the recovery period. Nitric oxide metabolites did not change, either. There were no significant relationships between plasma catecholamines and AM. Plasma brain natriuretic peptide did not change during the tilt test or the recovery period, either. These results suggest that the two molecular forms of AM, AM-m and AM-Gly in plasma, did not respond to the short term tilting stress. These findings may support the hypothesis that plasma AM is secreted in a constitutive manner from the vascular wall.

Evaluation of the percutaneous intramyocardial injection for local myocardial treatment

Therapeutic angiogenesis requires the induction of new blood vessel formation for the treatment of peripheral vascular and coronary artery disease. Efficacious application of this new therapy requires optimizing multiple factors, including the therapeutic agent, dosing, frequency of administration, and delivery modality. In this study, a helical needle drug infusion catheter was applied for optimal application of percutaneous intramyocardial delivery (PIMD). (125)Iodine-labeled albumin was injected by PIMD into the left ventricle myocardium in eight swine. After 1 hr, PIMD resulted in a high concentration of radiolabel at the treatment site; 16.4% +/- 2.1% of delivered and 81.4% +/- 2.6% of the total cardiac activity was concentrated at the site of delivery. The depth of needle penetration correlated with the myocardial retention of delivered protein. The myocardial retention of radiolabel in animals with shallow injections was 10.1% +/- 0.8%, compared to 18.9% +/- 3.3% retention after deep injections. The specific activity at the treatment site (radioactive counts per gram of tissue) was 115 +/- 36, 226 +/- 55, and 47 +/- 10 times higher compared to liver, lung, and kidney, respectively. Continuous coronary sinus and aortic blood sampling indicates that within 15 min following intramyocardial injection, a significant amount of nonretained protein is found within the coronary sinus. This study defines some of the parameters that can affect optimal application of PIMD and demonstrates that PIMD is a safe and efficient method for local drug delivery.