scholarly journals Composition of Sexual Fluids in Cycas revoluta Ovules During Pollination and Fertilization

Author(s):  
Patrick von Aderkas ◽  
Stefan Little ◽  
Massimo Nepi ◽  
Massimo Guarnieri ◽  
Madeline Antony ◽  
...  

AbstractThe composition of fluids that mediate fertilization in cycads is described for the first time. Using tandem mass spectrometry, proteomes of two stages of fluid production, megagametophyte fluid and archegonial chamber fluid production, are compared in Cycas revoluta. These were compared with the proteome of another sexual fluid produced by ovules, the pollination drop proteins. Cycad ovules produce complex liquids immediately prior fertilization. Compared with the pollination drops that mainly had few proteins in classes involved in defense and carbohydrate modification, megagametophyte fluid and archegonial chamber fluid had larger proteomes with many more protein classes, e.g. proteins involved in programmed cell death. Using high-performance liquid chromatography, megagametophyte fluid and archegonial chamber fluid were shown to have elevated concentrations of smaller molecular weight molecules including glucose, pectin and glutamic acid. Compared to megagametophyte fluid, archegonial chamber fluid had elevated pH as well as higher osmolality.

2019 ◽  
Author(s):  
Kent Griffith ◽  
Clare Grey

Nb18W8O69 (9Nb2O5×8WO3) is the tungsten-rich end-member of the Wadsley–Roth crystallographic shear (cs) structures within the Nb2O5–WO3 series. It has the largest block size of any known, stable Wadsley–Roth phase, comprising 5 ´ 5 units of corner-shared MO6 octahedra between the shear planes, giving rise to 2 nm ´ 2 nm blocks. Rapid lithium intercalation is observed in this new candidate battery material and 7Li pulsed field gradient nuclear magnetic resonance spectroscopy – measured in a battery electrode for the first time at room temperature – reveals superionic lithium conductivity. In addition to its promising rate capability, Nb18W8O69 adds a piece to the larger picture of our understanding of high-performance Wadsley–Roth complex metal oxides.


2019 ◽  
Vol 15 (6) ◽  
pp. 568-573
Author(s):  
Soheil Sedaghat ◽  
Ommoleila Molavi ◽  
Akram Faridi ◽  
Ali Shayanfar ◽  
Mohammad Reza Rashidi

Background: Signal transducer and activator of transcription 3 (STAT3), an oncogenic protein found constitutively active in many types of human malignancies, is considered to be a promising target for cancer therapy. Objective: In this study for the first time, a simple and accurate method has been developed for the determination of a STAT3 dimerization inhibitor called stattic in aqueous and plasma samples. Methods: A reverse-phase high-performance liquid chromatography (RP-HPLC) composed of C18 column as stationary phase, and the mixture of acetonitrile (60%) and water (40%) as mobile phase with a UV detection at 215 nm were applied for quantification of stattic. The developed method was validated by Food and Drug Administration (FDA) guideline. Results: The method provided a linear range between 1-40 and 2.5-40 µg mL-1 for aqueous and plasma samples, respectively, with a correlation coefficient of 0.999. The accuracy (as recovery) of the developed method was found to be between 95-105% for aqueous medium and 85-115% for plasma samples. The precision (as relative standard deviation) for aqueous and plasma samples was less than 6% and 15%, respectively. The sensitivity of the developed method based on FDA guideline was 1 µg mL-1 for aqueous and 2.5 µg mL-1 for plasma samples. Conclusion: These results show that the established method is a fast and accurate quantification for stattic in aqueous and plasma samples.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4166
Author(s):  
Agata Konarska ◽  
Elżbieta Weryszko-Chmielewska ◽  
Anna Matysik-Woźniak ◽  
Aneta Sulborska ◽  
Beata Polak ◽  
...  

The aim of this study was to conduct a histochemical analysis to localize lipids, terpenes, essential oil, and iridoids in the trichomes of the L. album subsp. album corolla. Morphometric examinations of individual trichome types were performed. Light and scanning electron microscopy techniques were used to show the micromorphology and localization of lipophilic compounds and iridoids in secretory trichomes with the use of histochemical tests. Additionally, the content of essential oil and its components were determined using gas chromatography-mass spectrometry (GC-MS). Qualitative analyses of triterpenes carried out using high-performance thin-layer chromatography (HPTLC) coupled with densitometric detection, and the iridoid content expressed as aucubin was examined with spectrophotometric techniques. We showed the presence of iridoids and different lipophilic compounds in papillae and glandular and non-glandular trichomes. On average, the flowers of L. album subsp. album yielded 0.04 mL/kg of essential oil, which was dominated by aldehydes, sesquiterpenes, and alkanes. The extract of the L. album subsp. album corolla contained 1.5 × 10−3 ± 4.3 × 10−4 mg/mL of iridoid aucubin and three triterpenes: oleanolic acid, β-amyrin, and β-amyrin acetate. Aucubin and β-amyrin acetate were detected for the first time. We suggest the use of L. album subsp. album flowers as supplements in human nutrition.


Author(s):  
Irshad Mohammad ◽  
Lucie Blondeau ◽  
Eddy Foy ◽  
Jocelyne Leroy ◽  
Eric Leroy ◽  
...  

Following the trends of alloys as negative electrodes for Na-ion batteries, the sodiation of the InSb intermetallic compound was investigated for the first time. The benefit of coupling Sb with...


Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 129
Author(s):  
Charlotte Cuerq ◽  
Claire Bordat ◽  
Charlotte Halimi ◽  
Emilie Blond ◽  
Marion Nowicki ◽  
...  

(1) Background: vitamin E is often supplemented in the form of tocopherol acetate, but it has poor bioavailability and can fail to correct blood tocopherol concentrations in some patients with severe cholestasis. In this context, α-tocopheryl polyethylene glycol succinate 1000 (TPGS) has been of value, but very little is known about the mechanisms of its absorption. The aim of our work was to evaluate the mechanisms of absorption/secretion of TPGS compared to tocopherol acetate (TAC) and α-tocopherol by human enterocyte-like Caco-2 TC7 cells. (2) Methods: two weeks post-confluence Caco-2 cells were incubated with tocopherol- or TAC- or TPGS-rich mixed micelles up to 24 h and, following lipid extraction, TAC and tocopherol amounts were measured by high performance liquid chromatography (HPLC) in apical, cellular, and basolateral compartments. (3) Results: at equivalent concentrations of tocopherol in the apical side, the amounts of tocopherol secreted at the basolateral pole of Caco-2 cells are (i) significantly greater when the tocopherol is in the free form in the micelles; (ii) intermediate when it is in the TAC form in the micelles (p < 0.001); and (iii) significantly lower with the TPGS form (p < 0.0001). Interestingly, our results show, for the first time, that Caco-2 cells secrete one or more esterified forms of the vitamin contained in TPGS at the basolateral side.


2014 ◽  
Vol 2 (15) ◽  
pp. 5427-5433 ◽  
Author(s):  
Shugang Li ◽  
Zhongcheng Yuan ◽  
Jianyu Yuan ◽  
Ping Deng ◽  
Qing Zhang ◽  
...  

An expanded isoindigo unit (IBTI) has been incorporated into a donor–acceptor conjugated polymer for the first time. The PCE of the solar cell device based on the new polymer reached 6.41% with a fill factor of 0.71.


RSC Advances ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 6798-6803
Author(s):  
Linchao Zeng ◽  
Jianhui Zhu ◽  
Minsu Liu ◽  
Peixin Zhang

Antimony nanosheet modified separator is prepared for high performance Li–S batteries for the first time.


2017 ◽  
Vol 41 (21) ◽  
pp. 12901-12909 ◽  
Author(s):  
Chunfeng Shao ◽  
Ziqiang Wang ◽  
Errui Wang ◽  
Shujun Qiu ◽  
Hailiang Chu ◽  
...  

Guanine was, for the first time, used as a nitrogen source during the synthesis of nitrogen-doped porous carbons (NMCs) with enhanced electrochemical performance.


Author(s):  
Inese Mierina ◽  
Rasma Seržaneļ ◽  
Maija Strele ◽  
Jūlija Moskaļuka ◽  
Elga Ivdre ◽  
...  

Abstract Various extracts of Japanese quince (Chaenomeles japonica) seeds obtained using organic solvents were studied for their polyphenol content and antiradical activity. It was established that petroleum ether, hexane, ethyl acetate, acetone, as well as toluene and chloroform extracts, in comparison to synthetic antioxidant butylated hydroxytoluene (BHT), demonstrate better (or comparable) activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Methods for detoxification of seeds, meals and press-cakes are proposed. Phenolic composition of different extracts (80% ethanol, 70% acetone), both acid and alkali hydrolysates of seeds, as well as seed oil methanol/water extract were analysed by means of high performance liquid chromatography (HPLC): chlorogenic acid was found for the first time in seed extract; protocatechuic acid predominated in all extracts. The content of other major phenolic acids was detected; it was found that seed oil contains syringic acid. It was determined that Japanese quince seeds contain almost ten times more α -tocopherol than barley grain. Due to the presence of α -tocopherol and phenolic compounds, seed oil and lipophilic extracts of seeds could serve as antioxidants.


2015 ◽  
Vol 3 (31) ◽  
pp. 8074-8079 ◽  
Author(s):  
Changyong Lan ◽  
Chun Li ◽  
Yi Yin ◽  
Huayang Guo ◽  
Shuai Wang

Single-crystalline GeS nanoribbons were synthesized by chemical vapor deposition for the first time. The nanoribbon photodetectors respond to the entire visible incident light with a response edge at around 750 nm and a high responsivity, indicating their promising application for high performance broadband visible-light photo-detection.


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