Agronomic Investigation of Spray Dispersion of Metal-Based Nanoparticles on Sunflowers in Real-World Environments.

In environmental and agronomic settings, even minor imbalances can trigger a range of unpredicted responses. Despite the widespread use of metal-based nanoparticles (NPs) and new bio-nanofertilizers, their impact on crop production is absent in the literature. Therefore, our research is focused on the agronomic effect of spray application of gold nanoparticles anchored to SiO2 mesoporous silica (AuSi-NPs), zinc oxide nanoparticles (ZnO-NPs), and iron oxide nanoparticles (Fe3O4-NPs) on sunflowers under real-world environments. Our findings revealed that the biosynthetically prepared AuSi-NPs and ZnO-NPs were highly effective in enhancing sunflower seasonal physiology, e.g., the value of the NDVI index increased from 0.012 to 0.025 after AuSi-NPs application. The distribution of leaf trichomes improved and the grain yield increased from 2.47 t ha-1 to 3.29 t ha-1 after ZnO-NPs application. AuSi-NPs treatment resulted in a higher content of essential linoleic acid (54.37%) when compared to the NPs-free control (51.57%), which had a higher determined oleic acid. No NPs or residual translocated metals were detected in the fully ripe sunflower seeds, except for slightly higher silica content after the AuSi-NPs treatment. Additionally, AuSi-NPs and NPs-free control showed wide insect biodiversity while ZnO-NPs treatment had the lowest value of phosphorus as anti-nutrient. Contradictory but insignificant effect on physiology, yield, and insect biodiversity was observed in Fe3O4-NPs treatment. Therefore, further studies are needed to fully understand the long-term environmental and agricultural sustainability of NPs applications.

Effects of Foliar Application of ZnO Nanoparticles on Lentil Production, Stress Level and Nutritional Seed Quality under Field Conditions.

Nanotechnology offers new opportunities for the development of novel materials and strategies that improve technology and industry. This applies especially to agriculture, and our previous field studies have indicated that zinc oxide nanoparticles provide promising nano-fertilizer dispersion in sustainable agriculture. However, little is known about the precise ZnO-NP effects on legumes. Herein, 1 mg·L-1 ZnO-NP spray was dispersed on lentil plants to establish the direct NP effects on lentil production, seed nutritional quality, and stress response under field conditions. Although ZnO-NP exposure positively affected yield, thousand-seed weight and the number of pods per plant, there was no statistically significant difference in nutrient and anti-nutrient content in treated and untreated plant seeds. In contrast, the lentil water stress level was affected, and the stress response resulted in statistically significant changes in stomatal conductance, crop water stress index, and plant temperature. Foliar application of low ZnO-NP concentrations therefore proved promising in increasing crop production under field conditions, and this confirms ZnO-NP use as a viable strategy for sustainable agriculture.

Foliar Application of Low Concentrations of Titanium Dioxide and Zinc Oxide Nanoparticles to the Common Sunflower under Field Conditions.

Nano-fertilisers have only recently been introduced to intensify plant production, and there still remains inadequate scientific knowledge on their plant-related effects. This paper therefore compares the effects of two nano-fertilisers on common sunflower production under field conditions. The benefits arising from the foliar application of micronutrient-based zinc oxide fertiliser were compared with those from the titanium dioxide plant-growth enhancer. Both the zinc oxide (ZnO) and titanium dioxide (TiO2) were delivered by foliar application in nano-size at a concentration of 2.6 mg·L-1. The foliar-applied nanoparticles (NPs) had good crystallinity and a mean size distribution under 30 nm. There were significant differences between these two experimental treatments in the leaf surfaces' trichomes diversity, ratio, width, and length at the flower-bud development stage. Somewhat surprisingly, our results established that the ZnO-NPs treatment induced generally better sunflower physiological responses, while the TiO2-NPs primarily affected quantitative and nutritional parameters such as oil content and changed sunflower physiology to early maturation. There were no differences detected in titanium or zinc translocation or accumulation in the fully ripe sunflower seeds compared to the experimental controls, and our positive results therefore encourage further nano-fertiliser research.

Effect of Foliar Spray Application of Zinc Oxide Nanoparticles on Quantitative, Nutritional, and Physiological Parameters of Foxtail Millet (Setaria italica L.) under Field Conditions.

It has been shown that the foliar application of inorganic nano-materials on cereal plants during their growth cycle enhances the rate of plant productivity by providing a micro-nutrient source. We therefore studied the effects of foliarly applied ZnO nanoparticles (ZnO NPs) on Setaria italica L. foxtail millet's quantitative, nutritional, and physiological parameters. Scanning electron microscopy showed that the ZnO NPs have an average particle size under 20 nm and dominant spherically shaped morphology. Energy dispersive X-ray spectrometry then confirmed ZnO NP homogeneity, and X-ray diffraction verified their high crystalline and wurtzite-structure symmetry. Although plant height, thousand grain weight, and grain yield quantitative parameters did not differ statistically between ZnO NP-treated and untreated plants, the ZnO NP-treated plant grains had significantly higher oil and total nitrogen contents and significantly lower crop water stress index (CWSI). This highlights that the slow-releasing nano-fertilizer improves plant physiological properties and various grain nutritional parameters, and its application is therefore especially beneficial for progressive nanomaterial-based industries.

Synthesis of 5α-androstane-3α,17ß-diol 17-O-glucuronide histaminyl conjugate for immunoassays.

Simple method of preparation of 5α-androstane-3α,17ß-diol 17-O-glucuronide N-histaminyl amide was developed for the construction of immunoanalytical kit. Improved method of glucuronide derivative synthesis was used, followed by hydroxybenzotriazole-dicyclohexylcarbodiimide coupling with histamine.

Novel approach to the preparation of hemisuccinates of steroids bearing tertiary alcohol group.

17ß-O-Hemisuccinates of typical representatives of Anabolic-Androgenic Steroids, 17ß-hydroxy-17-methylandrostan-4-en-3-one, 17ß-hydroxy-17-methyl-2-oxa-5α-androstan-3-one, 17ß-hydroxy-17-methyl-5α-androstano-[3,2-c]pyrazole, were prepared. Several methods for the hemisuccinate preparation were tested. The indirect method using 1-ethyl-3-(dimethylaminopropyl)carbodiimide coupling reagent to form an ester bond of steroid with 2-(trimethylsilyl)ethyl hydrogen butanedioate was finally applied. Using the selectively removable protecting group, the desired hemisuccinates of steroids bearing tertiary alcohol group were obtained.

Neuroactive steroids with perfluorobenzoyl group.

During an initial study in searching for the alternative derivatives suitable for photolabeling of neuroactive steroids, perfluorobenzoates and perfluorobenzamides in position 17 of 5ß-androstan-3α-ol were synthesized from the corresponding 17-hydroxy and 17-amino derivatives. After transformation into glutamates or sulfates, 17α-epimers had comparable inhibitory activity at NMDA receptors to the natural neurosteroid (20-oxo-5ß-pregnan-3ß-yl sulfate), however, were more potent (2- to 36-fold) than their 17ß-substituted analogs. In one case, fluorine in position 4' of perfluorobenzoate group was substituted with azide and activity of the final glutamate was retained comparing with the corresponding perfluorobenzoate. The series was expanded with perfluorobenzoyl derivatives of pregnanolone: Perfluorobenzamide of glutamate and perfluorobenzoate of 11α-hydroxy pregnanolone were prepared and tested. From nine tested compounds, four of them exhibit very good inhibition activity and can serve as promising leads for photolabeling experiments.

Azido analogs of neuroactive steroids.

Analogs of pregnanolone (3α-hydroxy-5ß-pregnan-20-one), modified in position 17 were prepared. Compounds with 20-keto pregnane side chain replaced completely by azide (17α- and 17ß-azido-5ß-androstan-3α-ol), compounds with its part replaced (20-azido-21-nor-5ß-pregnan-3α-ol), and compounds with keto group only replaced ((20R)- and (20S)-20-azido-5ß-pregnan-3α-ol) were synthesized using tosylate displacements with sodium azide or Mitsunobu reaction with azoimide. All five azido steroids were converted into corresponding sulfates. Subsequent tests for inhibition of glutamate induced response on NMDA receptors revealed that modification of pregnanolone sulfate side chain with azide did not disturb the activity and some of sulfates tested were more active than parent compound.

Stereoselectivity of sodium borohydride reduction of saturated steroidal ketones utilizing conditions of Luche reduction.

A series of keto steroids were reduced with sodium borohydride in the presence of cerium(III) chloride or samarium(III) iodide (Luche reduction). The ratios of axial and equatorial alcohols were determined by HPLC and the results were compared with those obtained by a standard sodium borohydride reduction. The best results were obtained with the 2-keto derivative 1, 7-keto derivatives 5 and 6, and 12-keto derivative 8 where the cerium(III) ion addition resulted in the inversion of the axial/equatorial ratios. The Luche reduction of the 20-keto derivative 11 improved the proportion of the (20S)-alcohol in a mixture of (20S)/(20R) alcohols up to 35% from 5% in a standard sodium borohydride reduction.

Steroids linked with amide bond-extended cholesterol.

New type of linear cholesterol-like molecules based on cholesterol extended by attachment of etienic acid derivatives was designed and oligosteroids with two to four units were synthesized. Amide bond was used for inter steroid connections and 1-hydroxybenzotriazole active ester method was adapted for their formations. Use of disteroids as larger building blocks was applied.

Steroid sulfatase and sulfuryl transferase activities in human brain tumors.

Neuroactive steroids (dehydroepiandrosterone, pregnenolone) and their sulfates act as modulators of glutamate and gamma-aminobutyrate type A receptors in the brain The physiological ratio of these neuromodulators is maintained by two enzymes present in the brain, namely, steroid sulfatase (STS) and steroid sulfuryl transferase (SULT). Following previous determination of their activities in monkey brains, their activities were evaluated in human brain tumors. Radioimmunoassay and GC-MS were used for determination of products. Both enzyme activities were measured in the 55 most frequent human brain tumors (glioblastomas, pituitary adenomas, meningiomas, astrocytomas). Significant differences were found in STS activity among investigated types of tumors except the pair of pituitary adenomas-glioblastomas, while significant differences were found in SULT activity among investigated types of tumors. Spontaneous tendency to form clusters was revealed when both enzyme activities were taken as coordinates. Clustering indicated an individual metabolic behavior of glioblastomas and 72.7% of pituitary adenomas. Astrocytomas, meningiomas and remaining 27.3% pituitary adenomas showed similarities in both enzymes' activities. Differences in STS and SULT activity did not depend on the sex or age of subjects.

Serum profiles of free and conjugated neuroactive pregnanolone isomers in nonpregnant women of fertile age.

BACKGROUND: Pregnanolone isomers (PI) with a hydroxy group in the 3alpha-position are neuroinhibitors operating via positive modulation of GABA(A) receptors. The 3beta-PI and sulfates of PI and pregnenolone exert the opposite effect. In addition to the brain's in situ synthesis, some circulating steroids can penetrate the blood-brain barrier. METHODS: To assess the physiological impact of peripheral endogenous neuroactive pregnanolone isomers and their polar conjugates in women, serum allopregnanolone (P3alpha5alpha), isopregnanolone (P3beta5alpha), pregnanolone (P3alpha5beta), epipregnanolone (P3beta5beta), pregnenolone, estradiol (including their polar conjugates), and additional steroids were measured in 16 women in the follicular and luteal phases of the menstrual cycle using gas chromatography/mass spectrometry and RIA for the analysis. Linear models and Spearman's correlations were used for data evaluation. RESULTS AND DISCUSSION: The levels of conjugated PI were from one to almost three orders of magnitude higher in comparison with the free steroids. The results indicate that a substantial proportion of the progesterone is metabolized in the sequence progesterone-->5beta-dihydroprogesterone-->P3alpha5beta-->conjugated P3alpha5beta. The sulfation of PI and particularly of P3alpha5beta moderates the levels of free PI and restrains estradiol biosynthesis via progesterone degradation. PI including the conjugates reflected changing progesterone formation during the menstrual cycle. In the follicular phase, the positive correlation with conjugated pregnenolone, the independence of progesterone, and the negative age relationships of PI indicate their adrenal origin. The dependence on progesterone and the independence of conjugated pregnenolone suggest a gonadal source of PI in the luteal phase. The neuroactivating PI prevailed over neuroinhibiting PI.

Syntheses of 19-[O-(carboxymethyl)oxime] haptens of epipregnanolone and pregnanolone.

O-(Carboxymethyl)oximes 1 and 2 derived from two epimeric 5beta-pregnanolones (3beta-hydroxy-5beta-pregnan-20-one and 3alpha-hydroxy-5beta-pregnan-20-one) in position 19 were prepared. Two synthetic routes were employed, both using protection of the 20-keto group after reduction into the (20R)-alcohol in the form of acetate. In the first route, (20R)-19-hydroxy-5beta-pregnan-3beta,20-diyl diacetate (3) was transformed into the corresponding 19-[O-(carboxymethyl)oxime] methyl ester 6, then deacetylated by acid and partially silylated with tert-butyldimethylsilyl chloride. The desired 3-O-silylated derivative 8 was separated, oxidized to the 20-ketone and protecting groups were sequentially removed to give the first title hapten 1. The second route started from (20R)-19-hydroxy-3-oxopregn-4-en-20-yl acetate (11), which was hydrogenated in the presence of base to the 5beta-pregnan-3-one derivative 12, protected in position 19 with tert-butyldimethylsilyl group and reduced with borohydride. The prevailing 3alpha-alcohol 15 was separated, protected in position 3 with a methoxymethyl group, deprotected in position 19 and transformed into the 19-[O-(carboxymethyl)oxime] 19. After deacetylation, esterification with diazomethane and oxidation in position 20, the pregnanolone skeleton was regenerated. Final deprotection steps gave the second title hapten 2. Both haptens, i.e., (19E)-3beta- and -3alpha-hydroxy-20-oxo-5beta-pregnan-19-al 19-[O-(carboxymethyl)oxime], were designed for the development of immunoassays of the corresponding parent neuroactive steroids.

Reinstatement of serum pregnanolone isomers and progesterone during alcohol detoxification therapy in premenopausal women.

BACKGROUND: Alcohol abuse is associated with menstrual irregularities related to the inhibition of progesterone secretion involved in regulation of the menstrual cycle. Reduced progesterone metabolites, including pregnanolone isomers (PIs), are efficient neuromodulators. The authors attempted to evaluate whether levels of PIs reflect impairment in progesterone biosynthesis in premenopausal women treated for alcohol addiction and whether alcohol detoxification therapy contributes to the restoration of their reproductive functions and psychosomatic stability by influencing steroid biosynthesis. METHODS: Serum allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one; P3alpha5alpha), pregnanolone (P3alpha5beta), isopregnanolone (P3beta5alpha), epipregnanolone (P3beta5beta), progesterone, pregnanolone sulfate (PregS), pregnanolone, and estradiol were measured in 20 women during therapy (at start, three days, 14 days, one month, and four months) by gas chromatography-mass spectrometry or radioimmunoassay. The results were evaluated by a linear mixed model for longitudinal data, with stage of the treatment and subject as categorical factors, phase of the menstrual cycle as a time-varying covariate, and age of the subject as a covariate and by regression in individual stages of the menstrual cycle. RESULTS: During detoxification treatment, progesterone increased in the luteal phase. P3alpha5alpha, P3beta5alpha, and P3beta5beta rose in both phases of the menstrual cycle. DISCUSSION: Given the similar mechanism in the effects of alcohol and steroids in activating gamma-aminobutyric acid A receptors, the restoration of progesterone and PIs during therapy could be explained by an adaptation to increasing requests for gamma-aminobutyric acid A-receptor activating substances owing to the cessation of alcohol intake or by the regeneration of progesterone formation. In conclusion, the reinstatement of progesterone, P3alpha5alpha, and P3beta5beta serum levels demonstrates the favorable effect of detoxification therapy on both reproductive functions and the psychosomatic stability of premenopausal women treated for alcohol addiction.

Altered profiles of serum neuroactive steroids in premenopausal women treated for alcohol addiction.

Long-term alcohol consumption results in menstrual irregularities due to the inhibition of progesterone secretion. Some progesterone metabolites, including three pregnanolone isomers (PI), abate, while pregnenolone sulfate (PregS) and dehydroepiandrosterone sulfate (DHEAS) increase, alcohol tolerance. The rationale of this study was to evaluate how the neuroactive steroids reflect the impaired progesterone formation in premenopausal women treated for alcohol addiction, and whether detoxification therapy could restore female reproductive functions and psychosomatic stability by reinstatement of the steroid biosynthesis. Accordingly, serum allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one (P3alpha5alpha)), pregnanolone (P3alpha5beta), isopregnanolone (P3beta5alpha) and epipregnanolone (P3beta5beta), progesterone, PregS, pregnenolone, 17alpha-hydroxy-pregnenolone (Preg17), 17alpha-hydroxy-progesterone (Prog17), DHEA, DHEAS, cortisol and estradiol were measured in 20 women during the therapy (start, 3 days, 14 days, 1 month, 4 months), and in 17 controls, using GC-MS or RIA and evaluated by age-adjusted ANCOVA with status and phase of the menstrual cycle (PMC) as factors, and status-PMC interaction. The patients exhibited depressed progesterone, Prog17, PI, and estradiol, a decreased progesterone/pregnenolone ratio, a decreased ratio of neuroinhibiting P3alpha5alpha to neuroactivating PregS, and an elevated PregS and PregS/pregnenolone ratio. The treatment mostly restored the indices. The reduction of neuroinhibiting pregnanolone isomers in the patients is primarily associated with the impairment in ovarian steroid biosynthesis. Nevertheless, changes in enzyme activities connected with the formation of PI and the influence of altered physiological requirements on the balance between endogenous neuroinhibiting and neuroactivating steroids are also likely. The reinstatement of serum estradiol, progesterone, and PI during the therapy demonstrates its favorable effect on both reproductive functions and the psychosomatic stability of the patients.

Etienic etienate as synthon for the synthesis of steroid oligoester gelators.

Linear oligoesters based on etienic acid (3beta-hydroxyandrost-5-ene-17beta-carboxylic acid) containing four steroid units were prepared using a 2+2 synthetic strategy in a successful synthesis of 3beta-{[3beta-({3beta-[(3beta-hydroxyandrost-5-ene-17beta-carbonyl)oxy]androst-5-ene-17beta-carbonyl}oxy)androst-5-ene-17beta-carbonyl]oxy}androst-5-ene-17beta-carboxylic acid. The main problems with deprotection were overcome by using orthogonal groups as O-nitrates and 2-(trimethylsilyl)ethyl ethers.

The identification and simultaneous quantification of 7-hydroxylated metabolites of pregnenolone, dehydroepiandrosterone, 3beta,17beta-androstenediol, and testosterone in human serum using gas chromatography-mass spectrometry.

7-Hydroxy-metabolites of dehydroepiandrosterone (DHEA) and 3beta,17beta-androstenediol (AD) possess immunomodulatory and neuroprotective properties; therefore, the measurement of these steroids in patients with autoimmune diseases or disturbances in the CNS may be of interest. A gas chromatography-mass spectrometry (GC-MS) method for the determination of 7-hydroxy-metabolites of pregnenolone, DHEA, AD, and testosterone including the parent steroids was applied to serum samples from 12 adult men (27-66 years), 13 male adolescents (13-20 years), 5 boys (6-10 years), 15 women in the follicular phase of the menstrual cycle (22-45 years), 17 women in the luteal phase (22-45 years), and 4 girls (6-10 years). The steroids were age and sex dependent, but independent of the menstrual cycle. The ratio of the 7alpha-hydroxy-metabolites to their parent steroids were age dependent, exhibiting an increasing trend (p < 0.0001, ANOVA) from pregnenolone (5%) to AD (20%). The ratio of 7beta- to 7alpha-metabolites ranged from 0.6 to 1. These results are consistent with models suggesting 7alpha-hydroxylation of the parent steroid, conversion to a 7-oxo-steroid and finally to the 7beta-hydroxylated-metabolite. Partial correlations suggested that 7-hydroxylation might reduce the concentration of circulating androgens. Despite the three times lower concentration of AD-metabolites, their antiglucocorticoid, immunomodulatory, and neuroprotective effects may be comparable to that of DHEA based on their reported greater biological activity.

Derivatives of 16alpha-hydroxy-dehydroepiandrosterone with an additional 7-oxo or 7-hydroxy substituent: synthesis and gas chromatography/mass spectrometry analysis.

Derivatives of 16alpha-hydroxy-dehydroepiandrosterone, which have an additional oxygen substituent at position 7 (oxo or hydroxy group), were synthesized. Firstly, 17,17-dimethoxyandrost-5-ene-3beta,16alpha-diyl diacetate was prepared and then oxidized with a complex of chromium(VI) oxide and 2,5-dimethylpyrazole to the respective 7-oxo derivative. This key intermediate was both deprotected or reduced by l-Selectride or sodium borohydride in the presence of cerium(III) chloride and then deprotected to give 7-oxo, 7alpha-hydroxy and 7beta-hydroxy derivatives of 16alpha-hydroxy-dehydroepiandrosterone. The target compounds were characterized by (1)H and (13)C NMR spectra and in the form of O-methyloxime-trimethylsilyl derivatives, by gas chromatography/mass spectrometry methods.

Neuroactive pregnanolone isomers during pregnancy.

The pregnanolone isomers (PI) allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one), pregnanolone (3alpha-hydroxy-5beta-pregnan-20-one), isopregnanolone (3beta-hydroxy-5alpha-pregnan-20-one), epipregnanolone (3beta-hydroxy-5beta-pregnan-20-one), progesterone, and estradiol were measured in 138 pregnant women. The sampling was carried out from the first through the 10th month of pregnancy. Gas chromatography-mass spectrometry analysis and RIA were used for the measurement of steroid levels. The ratios of individual PI were similar to those found previously around parturition: about 25:10:7:1 for allopregnanolone, pregnanolone, isopregnanolone, and epipregnanolone, respectively. All the PI showed a significant increase during pregnancy, which was more pronounced in the 3alpha-steroids. The results indicated changing ratios between 3alpha- and 3beta-PI and between 5alpha- and 5beta-PI throughout pregnancy. The constant allopregnanolone/isopregnanolone ratio found through pregnancy weakened the hypothesis of the role of isopregnanolone in the onset of parturition. The ratio of estradiol (stimulating uterine activity) to 5alpha-PI and epipregnanolone exhibited significant changes during pregnancy in favor of estradiol up to the sixth or seventh month, in contrast to the constant estradiol/pregnanolone ratio. A pregnancy-stabilizing role of pregnanolone, counterbalancing the stimulating effect of estradiol on the onset of parturition, was suggested.

15Alpha-hydroxyprogesterone in male sea lampreys, Petromyzon marinus L.

There is growing evidence that sea lampreys, Petromyzon marinus L., produce gonadal steroids differing from those of other vertebrates by possessing an additional hydroxyl group at the C15 position. Here we demonstrate that sea lamprey testes produce 15alpha-hydroxyprogesterone (15alpha-P) in vitro when incubated with tritiated progesterone, that 15alpha-P is present in the plasma of sea lampreys, and that plasma concentrations of immunoreactive (ir) 15alpha-P rise dramatically in response to injections of gonadotropin-releasing hormone (GnRH). The identity of the tritiated 15alpha-P produced in vitro was confirmed by co-elution with standard 15alpha-P on high performance liquid chromatography, co-elution with standard and acetylated 15alpha-P on thin layer chromatography, and specific binding to antibodies raised against standard 15alpha-P. The in vitro conversion was used to produce tritiated 15alpha-P label for a radioimmunoassay (RIA), which is able to detect 15alpha-P in amounts as low as 2 pg per tube. The RIA has been used to measure the plasma concentrations of 15alpha-P in males given two serial injections, 24 h apart, of either lamprey GnRH I or GnRH III (50, 100, or 200 microg/kg) or saline control, with plasma being sampled 8 and 24 h after the second injection. Plasma concentrations of ir-15alpha-P rose from < 1 to 36 ng/ml (mean of all treatments) 8 h after injection and declined within 24 h. This is the first time that an RIA has detected such high steroid concentrations in lampreys. This finding is suggestive of a role for 15alpha-P in control of reproduction in the sea lamprey.