Nutrient supplementation-induced metabolic profile changes and early appearance of free N-glycans in nutrient deficient tomato plants revealed by mass spectrometry.

Inorganic fertilizers are routinely used in large scale crop production for the supplementation of nitrogen, phosphorus, and potassium in nutrient poor soil. To explore metabolic changes in tomato plants grown on humic sand under different nutritional conditions, matrix-assisted laser desorption ionization (MALDI) mass spectrometry was utilized for the analysis of xylem sap. Variations in the abundances of metabolites and oligosaccharides, including free N-glycans (FNGs), were determined. Statistical analysis of the sample-related peaks revealed significant differences in the abundance ratios of multiple metabolites, including oligosaccharides, between the control plants, grown with no fertilizers, and plants raised under "ideal" and "nitrogen deficient" nutritional conditions, i.e., under the three treatment types. Among the 36 spectral features tentatively identified as oligosaccharides, the potential molecular structures for 18 species were predicted based on their accurate masses and isotope distribution patterns. To find the spectral features that account for most of the differences between the spectra corresponding to the three different treatments, multivariate statistical analysis was carried out by orthogonal partial least squares-discriminant analysis (OPLS-DA). They included both FNGs and non-FNG compounds that can be considered as early indicators of nutrient deficiency. Our results reveal that the potential nutrient deficiency indicators can be expanded to other metabolites beyond FNGs. The m/z values for 20 spectral features with the highest variable influence on projection (VIP) scores were ranked in the order of their influence on the statistical model.

Determination of field capacity in the Chibunga and Guano rivers micro-basins.

Background: The micro-basins of the Chibunga and Guano rivers are located within the sub-basin of the Chambo River, which starts at the thaw of the Chimborazo, crosses the cities of Guano and Riobamba, and ends in the Chambo River. These rivers are considered fluvial hydrological forces and geological limits of the aquifer, located in this sub-basin. For this reason, our investigation addressed the field capacity in the micro-basins of Chibunga and Guano rivers, to determine the maximum retention potential, i.e., the saturation of water in the soil. Methods: We investigated the change of precipitation to runoff through the correlations between the characteristics of the soil and its vegetation. We applied the Curve Number (CN) method introduced by the United States Soil Conservation Service (USSCS); this represents an empirical model, which relates the vegetation cover to the geological and topographic conditions of the soil. Along with the geographic information system, the model allows to represent the variation of runoffs for each micro-basin, according to the different land use categories, over the time frame from 2010 to 2014. Results: We found that the maximum retention potential is directly affected by CN values, representing the runoff potential. Highest values of 100 belong to the wetlands, urban area, snow, and water, as rain is converted directly into runoff, being impervious areas. The Guano river micro-basin possesses clay soil with CN of 78, the soil texture for eucalyptus forest is clay loam, and its CN value, 46, is the lowest of the data set. Knowledge of field capacity allows to properly evaluate the storage capacity of soil and water conservation. Conclusions: Results of this work will be useful in the quantification of the water balance, to determine the water supply and demand.

Translating Scientific Knowledge to Government Decision Makers Has Crucial Importance in the Management of the COVID-19 Pandemic.

In times of epidemics and humanitarian crises, it is essential to translate scientific findings into digestible information for government policy makers who have a short time to make critical decisions. To predict how far and fast the disease would spread across Hungary and to support the epidemiological decision-making process, a multidisciplinary research team performed a large amount of scientific data analysis and mathematical and socioeconomic modeling of the COVID-19 epidemic in Hungary, including modeling the medical resources and capacities, the regional differences, gross domestic product loss, the impact of closing and reopening elementary schools, and the optimal nationwide screening strategy for various virus-spreading scenarios and R metrics. KETLAK prepared 2 extensive reports on the problems identified and suggested solutions, and presented these directly to the National Epidemiological Policy-Making Body. The findings provided crucial data for the government to address critical measures regarding health care capacity, decide on restriction maintenance, change the actual testing strategy, and take regional economic, social, and health differences into account. Hungary managed the first part of the COVID-19 pandemic with low mortality rate. In times of epidemics, the formation of multidisciplinary research groups is essential for policy makers. The establishment, research activity, and participation in decision-making of these groups, such as KETLAK, can serve as a model for other countries, researchers, and policy makers not only in managing the challenges of COVID-19, but in future pandemics as well.

Determination of complex type free, non-conjugated oligosaccharide glucose unit values in tomato xylem sap for early detection of nutrient deficiency.

Although knowledge on glycan biosynthesis and processing is continuously maturing, there are still a limited number of studies that examine biological functions of N-glycan structures in plants, which remain virtually unknown. Here, the statistical correlation between nutrient (nitrogen) deficiency symptoms of crops and changes in 8-aminopyrene-1,3,6-trisulfonic acid (APTS)-labeled complex type free oligosaccharides is reported. While deficiency symptoms are predicted by multispectral images and Kjeldahl digestion, APTS-labeled complex type free oligosaccharides are identified by their glucose unit (GU) values in tomato xylem sap, using capillary electrophoresis with laser induced fluorescence detection (CE-LIF). Given the limited number of structures obtained from plants, archived in the literature, in the future, it is intended to create an open access database of promising indicators, namely, glycan structures that are presumably responsible for the nutrient deficiency caused stress in plants (http://glycoplants.org).

Soluble nitrogen forms in sand soil of Pallag: a quantitative report.

Nitrogen (N) is a crop macronutrient of major importance, which affects both plant growth and yield. In this paper we discuss the humus content (%) and various soluble N forms (NO 3-, total N, nitrate-N, ammonium-N, and organic nitrogen) available in humus sand soil samples originating from the Pallag Experimental Station of Horticulture at the University of Debrecen, Hungary. We found 45.4% nitrate-N and 13.8% nitrite-N of total N content present in the soil. Considering the percentage distribution of soluble N forms present at the Pallag Experimental Station, we recommend using this soil in further pot experiments, given that this has optimal nutrient supply capacity. In addition, we examined possible statistical correlations between humus% and N forms.

Effect of herbicides on soil respiration: a case study conducted at Debrecen-Látókép Plant Cultivation Experimental Station.

Measuring the effect of herbicides on the natural environment is essential to secure sustainable agriculture practices. Amount of carbon dioxide released by soil microorganisms (soil respiration) is one of the most important soil health indicators, known so far. In this paper we present a comprehensive quantifying study, in which we measured the effect of 14 herbicides on soil respiration over 16 years, from 1991 to 2017, at Debrecen-Látókép Plant Cultivation Experimental Station. Investigated herbicides contained different active ingredients and were applied in various doses. It was found that 11 out of the examined 14 herbicides had a detrimental effect on soil respiration.

Effects of Cinnamaldehyde on Smooth Muscle Preparations.

The effects of cinnamaldehyde (CNA), known as a transient receptor potential ankyrin 1 (TRPA1) agonist, on guinea-pig ileum and urinary bladder were studied in isolated organ experiments. Contractile effects were found to be present on both preparations. In the ileum, both cholinergic and purinergic (pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid tetrasodium salt-sensitive) mechanisms are involved; the TRPA1 antagonist A967079 (1 µmol/L) significantly reduced the response. The contractile response to CNA in the bladder, but not in the ileum, was significantly reduced by in vitro capsaicin desensitization. In the bladder A967079 or the TRPV1 antagonist, BCTC failed to reduce the response. A direct relaxation on the smooth muscle was detected in the precontracted ileum. In the precontracted urinary bladder, CNA also caused relaxation that was insensitive to capsaicin pretreatment. It is suggested that CNA excites the muscles of the bladder via activation of capsaicin-sensitive nerves; in the ileum, it may interact with TRPA1 located on tissue elements that initiate both purinergic and cholinergic mechanisms. The relaxant effects of CNA may be due to the direct inhibition of the smooth muscles.

Effects of the venom of the brown bullhead catfish (Ameiurus nebulosus) on isolated smooth muscles.

Aqueous extract of the spines of the brown bullhead catfish (Ameiurus nebulosus Lesueur, 1819) caused contraction of the guinea-pig small intestine in vitro, a widely-used preparation in pharmacology. The action is dependent on extracellular Ca2+, and probably takes place on the smooth muscle cells. Mouse gastrointestinal preparations were also contracted by the extract. Stings by the spines of this fish species causes a painful sensation in man. We tested the effect of an extract of spines in isolated organ experiments on innervated smooth muscle preparations. In the guinea-pig ileum, the response to the extract was abolished by the Ca2+-channel blocker nifedipine, but only slightly reduced by atropine (a muscarine receptor antagonist) or tetrodotoxin (TTX; a blocker axonal conduction) or antagonists for P2X purinoceptors. Blocking of serotonin or histamine H1 receptors, tachykinin NK1 receptors, functional impairment of capsaicin-sensitive sensory nerve endings or inhibition of cyclo-oxygenases failed to influence the contractile effect of the extract. No inhibitory action of the extract was detected on the ileum subject to electrical motor nerve stimulation.

Evidence Supports Tradition: The in Vitro Effects of Roman Chamomile on Smooth Muscles.

The dried flowers of Chamaemelum nobile (L.) All. have been used in traditional medicine for different conditions related to the spasm of the gastrointestinal system. However, there have been no experimental studies to support the smooth muscle relaxant effect of this plant. The aim of our research was to assess the effects of the hydroethanolic extract of Roman chamomile, its fractions, four of its flavonoids (apigenin, luteolin, hispidulin, and eupafolin), and its essential oil on smooth muscles. The phytochemical compositions of the extract and its fractions were characterized and quantified by HPLC-DAD, the essential oil was characterized by GC and GC-MS. Neuronally mediated and smooth muscle effects were tested in isolated organ bath experiments on guinea pig, rat, and human smooth muscle preparations. The crude herbal extract induced an immediate, moderate, and transient contraction of guinea pig ileum via the activation of cholinergic neurons of the gut wall. Purinoceptor and serotonin receptor antagonists did not influence this effect. The more sustained relaxant effect of the extract, measured after pre-contraction of the preparations, was remarkable and was not affected by an adrenergic beta receptor antagonist. The smooth muscle-relaxant activity was found to be associated with the flavonoid content of the fractions. The essential oil showed only the relaxant effect, but no contracting activity. The smooth muscle-relaxant effect was also detected on rat gastrointestinal tissues, as well as on strip preparations of human small intestine. These results suggest that Roman chamomile extract has a direct and prolonged smooth muscle-relaxant effect on guinea pig ileum which is related to its flavonoid content. In some preparations, a transient stimulation of enteric cholinergic motoneurons was also detected. The essential oil also had a remarkable smooth muscle relaxant effect in this setting. Similar relaxant effects were also detected on other visceral preparations, including human jejunum. This is the first report on the activity of Roman chamomile on smooth muscles that may reassure the rationale of the traditional use of this plant in spasmodic gastrointestinal disorders.

Serotonin or the Mucosa Do Not Mediate the Motor Effect of Allyl Isothiocyanate in the Guinea-Pig Small Intestine.

BACKGROUND: Serotonin (5-hydroxytryptamine, 5-HT), originating from the enterochromaffin cells has been reported to mediate the contractile effect of the sensory stimulant and TRPA1 activator allyl isothiocyanate (AITC) in the guinea-pig small intestine [Nozawa et al: Proc Natl Acad Sci U S A 2009;106:3408-3413]. SUMMARY: In the present experiments, the nerve-mediated contraction of this preparation due to AITC was not inhibited by a combination of methysergide (broad-spectrum 5-HT antagonist; 0.3 µmol/l), Y 25130 (azasetron, 5-HT3 receptor antagonist; 1 µmol/l) and SB 204070 (5-HT4 receptor antagonist; 2 µmol/l) or by 5-HT receptor desensitization, that is, pretreatments that practically abolished contractions of similar size in response to exogenous 5-HT, without causing nonspecific effects. AITC also contracted longitudinal muscle-myenteric plexus preparations, an effect also fully resistant to the combination of 5-HT receptor antagonists. The pharmacology of AITC in strip preparations matched that in the whole ileum. Key Messages: It is concluded that neither endogenous 5-HT nor the gut mucosa contributes to the excitatory effect of AITC in the guinea-pig small intestine. The combination of 5-HT antagonists elaborated is suitable for studying the possible involvement of 5-HT in motor responses of the guinea-pig intestine.

The TRPA1 Activator Allyl Isothiocyanate (AITC) Contracts Human Jejunal Muscle: Pharmacological Analysis.

The contractile effect of AITC (300 µM) on human jejunal longitudinal strips was inhibited by the TRPA1 antagonist HC 030031 and atropine or scopolamine, but was insensitive to tetrodotoxin, purinoceptor antagonists or capsaicin desensitization. It is concluded that TRPA1 activation stimulates a cholinergic mechanism in a tetrodotoxin-resistant manner.

High-Concentration Piperine: Capsaicin-Sensitive and -Insensitive Effects on Isolated Organs.

Piperine (P), a sensory stimulant in black pepper, is an agonist on TRPV1 receptors. Earlier work has showed capsaicin-sensitive and -insensitive mechanisms of the contractile action of P on the intestine. The current isolated organ study in the guinea-pig ileum, urinary bladder and trachea (a) confirms the presence of such components of effect (ileum and bladder); (b) indicates TRPV1 involvement in the effect of 5 or 30 µmol/l of P on the basis of an inhibitory action of the antagonist BCTC (ileum); (c) indicates that HC 030031-sensitive TRPA1 receptors and nifedipine-sensitive Ca(2+) channels contribute to the capsaicin-resistant contraction to 30 µmol/l P (ileum) and (d) shows that the contractile effect of P up to 100 µmol/l (guinea-pig trachea) or 30 µmol/l (guinea-pig urinary bladder) is capsaicin-sensitive and mediated by TRPV1 receptors/channels.

Dual excitatory and smooth muscle-relaxing effect of Sideritis montana extract on guinea-pig ileum.

The neuronal and smooth muscle effects of a methanol extract prepared from the air-dried flowering aerial parts of Sideritis montana L. (SME) was tested in vitro on Guinea-pig ileum. The chemical composition of the investigated extract was analysed by HPLC-MS, and chrysoeriol, chlorogenic acid and caffeic acid were detected as main constituents. The isolated organ assay showed that S. montana extract caused an immediate contraction and a more slowly developing inhibitory response in the ileum. The SME-induced contractions were strongly inhibited by the acetylcholine muscarinic receptor antagonist atropine (0.5 µM), but not by either the Na+ channel blocker tetrodotoxin (TTX; 0.5 µM) or the histamine H1 receptor antagonist chloropyramine (0.5 µM). Selective desensitization of capsaicin-sensitive neurons by the sensory neuron stimulant and blocker capsaicin did not influence the contractile effect of SME. As to the spasmolytic effect, SME inhibited the effects of electrical field stimulation, exogenous acetylcholine, and histamine. These smooth muscle-relaxing effects were reversible in 40 min by repeated renewals of the bathing solution.

Smooth muscle-depressant activity of AP-18, a putative TRPA1 antagonist in the guinea pig intestine.

AP-18, a putative antagonist at TRPA1 receptor/ion channel, caused smooth muscle relaxation at 10-100 µmol/l. It inhibited cholinergic twitch responses evoked by electrical field stimulation of cholinergic nerves as well as contractions in response to acetylcholine and histamine in the guinea pig small intestine. AP-18 (30 µmol/l) blocked spontaneous contractions of longitudinal strips of human jejunum. It is concluded that AP-18 may have limited value in studying TRPA1-mediated responses in smooth muscles and should probably be used with care in other preparations because of possible nonspecific effects.

Trojans in habitable zones.

With the aid of numerical experiments we examined the dynamical stability of fictitious terrestrial planets in 1:1 mean motion resonance with Jovian-like planets of extrasolar planetary systems. In our stability study of the so-called "Trojan" planets in the habitable zone, we used the restricted three-body problem with different mass ratios of the primary bodies. The application of the three-body problem showed that even massive Trojan planets can be stable in the 1:1 mean motion resonance. From the 117 extrasolar planetary systems only 11 systems were found with one giant planet in the habitable zone. Out of this sample set we chose four planetary systems--HD17051, HD27442, HD28185, and HD108874--for further investigation. To study the orbital behavior of the stable zone in the different systems, we used direct numerical computations (Lie Integration Method) that allowed us to determine the escape times and the maximum eccentricity of the fictitious "Trojan planets."