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121.
Reina M Ruiz-Mesia W Ruiz-Mesia L Martínez-Díaz R González-Coloma A 《Zeitschrift für Naturforschung. C, Journal of biosciences》2011,66(5-6):225-234
Five oxindole alkaloids, three plumerane-type alkaloids, subtype haplophitine, and one aspidospermatane-type alkaloid, subtype tubotaiwine, were isolated from the medicinal plants Aspidosperma rigidum and A. schultesii. One compound was identified as the transoid conformer of 18-oxo-O-methylaspidoalbine which was not previously described. The antiparasitic activity of all compounds against Trypanosoma cruzi and Leishmania infantum and their non-specific cytotoxicity against mammalian cells were also determined. 相似文献
122.
Yusuf Muhammad Noor Nurul Hidayah Samsulrizal Noor Azah Jema'on Kheng Oon Low Aizi Nor Mazila Ramli Noor Izawati Alias Siti Intan Rosdianah Damis Siti Fatimah Zaharah Mohd Fuzi Mohd Noor Mat Isa Abdul Munir Abdul Murad Mohd Firdaus Mohd Raih Farah Diba Abu Bakar Nazalan Najimudin Nor Muhammad Mahadi Rosli Md. Illias 《Gene》2014
Bacillus lehensis G1 is a Gram-positive, moderately alkalitolerant bacterium isolated from soil samples. B. lehensis produces cyclodextrin glucanotransferase (CGTase), an enzyme that has enabled the extensive use of cyclodextrin in foodstuffs, chemicals, and pharmaceuticals. The genome sequence of B. lehensis G1 consists of a single circular 3.99 Mb chromosome containing 4017 protein-coding sequences (CDSs), of which 2818 (70.15%) have assigned biological roles, 936 (23.30%) have conserved domains with unknown functions, and 263 (6.55%) have no match with any protein database. Bacillus clausii KSM-K16 was established as the closest relative to B. lehensis G1 based on gene content similarity and 16S rRNA phylogenetic analysis. A total of 2820 proteins from B. lehensis G1 were found to have orthologues in B. clausii, including sodium–proton antiporters, transport proteins, and proteins involved in ATP synthesis. A comparative analysis of these proteins and those in B. clausii and other alkaliphilic Bacillus species was carried out to investigate their contributions towards the alkalitolerance of the microorganism. The similarities and differences in alkalitolerance-related genes among alkalitolerant/alkaliphilic Bacillus species highlight the complex mechanism of pH homeostasis. The B. lehensis G1 genome was also mined for proteins and enzymes with potential viability for industrial and commercial purposes. 相似文献
123.
Michal Hlodák Peter Matúš Lucia Kořenková 《International journal of phytoremediation》2016,18(2):195-199
Heavy metal phytotoxicity assessments usually use soluble metal compounds in spiked soils to evaluate metal bioaccumulation, growth inhibition and adverse effects on physiological parameters. However, exampling mercury phytotoxicity for barley (Hordeum vulgare) this paper highlights unsuitability of this experimental approach. Mercury(II) in spiked soils is extremely bioavailable, and there experimentally determined bioaccumulation is significantly higher compared to reported mercury bioaccumulation efficiency from soils collected from mercury-polluted areas. Our results indicate this is not affected by soil sorption capacity, thus soil ageing and formation of more stable mercuric complexes with soil fractions is necessary for reasonable metal phytotoxicity assessments. 相似文献
124.
Sudden marine flooding within otherwise continental successions of the Triassic is unusual. The Tabular Cover of the SE paleomargin of the Iberian Massif is characterized by continental Triassic redbed facies composed of sandstones and siltstones, with gypsum-rich levels in the transition to Jurassic limestones. These Triassic deposits were developed in a fluvial-coastal system and they are 300 m thick in the Puente Génave-Villarrodrigo area, eastern Jaén Province, Spain. An unexpected sandstone-limestone unit in the lower part of this formation, recognized over more than 30 km, contains marine reptile bones in a storm bed or tsunami deposit. The lower part of this unit is characterized by a sandstone with sedimentary structures indicative of high-energy conditions as well as by fossil remains of marine reptiles. This bed ranges from 0 to 90 cm in thickness, and in some outcrops pinches out rapidly within a few meters. The upper part of the studied unit is a limestone with common trace fossils and abundant remains of marine reptiles, comprising isolated and fragmented pieces of sauropterygians (nothosaurs, pachypleurosaurs, and placodonts). Most abundant are vertebrae and ribs. In some outcrops, the top of this bed presents a dense accumulation of well-preserved small gastropods. The limestone is overlain by red siltstones and sandstones. The studied unit is interpreted as a marine deposit representing a high-energy event and records exceptional marine flooding in a distal fluvial environment, in fact the only open-marine deposit in the Villarrodrigo section. The sedimentary structures in the lower part of the unit are typical of high-energy deposits and indicate deposition in a single episode, probably related to a storm surge or a tsunami. The fragmentation, disarticulation, and dispersion of the vertebrate bones and the imbrication of bioclasts are consistent with a high-energy event that favored the concentration of bones according to size and density. 相似文献
125.
126.
María Florencia Gottardo Matías L. Pidre Camila Zuccato Antonela S. Asad Mercedes Imsen Gabriela Jaita Marianela Candolfi Víctor Romanowski Adriana Seilicovich 《Apoptosis : an international journal on programmed cell death》2018,23(2):143-151
Pituitary tumors are the most common primary intracranial neoplasms. Humanin (HN) and Rattin (HNr), a rat homolog of HN, are short peptides with a cytoprotective action. In the present study, we aimed to evaluate whether endogenous HNr plays an antiapoptotic role in pituitary tumor cells. Thus, we used RNA interference based on short-hairpin RNA (shRNA) targeted to HNr (shHNr). A plasmid including the coding sequences for shHNr and dTomato fluorescent reporter gene was developed (pUC-shHNr). Transfection of somatolactotrope GH3 cells with pUC-shHNr increased apoptosis, suggesting that endogenous HNr plays a cytoprotective role in pituitary tumor cells. In order to evaluate the effect of blockade of endogenous HNr expression in vivo, we constructed a recombinant baculovirus (BV) encoding shHNr (BV-shHNr). In vitro, BV-shRNA was capable of transducing more than 80% of GH3 cells and decreased HNr mRNA. Also, BV-shHNr increased apoptosis in transduced GH3 cells. Intratumor injection of BV-shHNr to nude mice bearing s.c. GH3 tumors increased the number of apoptotic cells, delayed tumor growth and enhanced survival rate, suggesting that endogenous HNr may be involved in pituitary tumor progression. These preclinical data suggests that the silencing of HN expression could have a therapeutic impact on the treatment of pituitary tumors. 相似文献
127.
This study aimed to understand the use of “invasive species” as a normative concept and discuss its implications in conservation science, using introduced ascidians worldwide as model species. A specific search in Web of Science was performed and articles suitable for analysis were selected. Each article was classified according to the type of environment, species under study, type of effects and spread that ascidians are linked to. Most of the 184 articles analysed did not consider dispersal or effects as study subject (82 and 71%, respectively). Most research was conducted in laboratory conditions (41%) or human-made environments (32%) or indicating few escapes to natural environments. Almost half of the articles (47%) were made with the six more conspicuous introduced ascidians and this raised to 70% while considering articles that worked with two or more (pooled) species. The normative use of “invasive” is widely used regarding introduced ascidians. Spread and effects, necessary conditions to consider a species as invasive, are notoriously understudied. Most research was not conducted in natural environments and over a few species, weakening the perception of introduced ascidians as a conservation problem. To discuss the extent of the normative use of invasion science is important to distinguish two phenomena: are some species intrinsically problematic for conservation (i.e. invasive) or is the movement of non-native species (i.e. biological invasion) the conservation problem? By using invasive as a normative concept, we risk ending with a weakened concept potentially hindering the progress of invasion science. 相似文献
128.
Katarzyna Grychowska Rafał Kurczab Paweł Śliwa Grzegorz Satała Krzysztof Dubiel Mikołaj Matłoka Rafał Moszczyński-Pętkowski Jerzy Pieczykolan Andrzej J. Bojarski Paweł Zajdel 《Bioorganic & medicinal chemistry》2018,26(12):3588-3595
Based on pyrroloquinoline scaffold bearing 5-HT2C agonists, a series of arylsulfonamide derivatives of 1H-pyrrolo[2,3-f]quinoline and 1H-pyrrolo[3,2-h]quinoline, substituted at position 3 with tetrahydropyridine, were synthesized and evaluated in vitro for their affinity for 5-HT6 receptors. A structure–activity relationship study showed that the 1H-pyrrolo[3,2-h]quinoline scaffold was more favorable for 5-HT6R binding than the 1H-pyrrolo[2,3-f]quinoline one, suggesting dependence upon the type of condensation of the pyrrole and quinoline rings. As revealed by quantum-chemical calculations and molecular dynamic studies, position of the quinoline nitrogen atom in the planar pyrroloquinoline skeleton might affect the spatial orientation of the arylsulfonyl fragment, as a result of structure stabilization by internal hydrogen bonds. 相似文献
129.
The chemical/osmotic conditions for growth and plumbagin accumulation of Drosophyllum lusitanicum Link. suspension cultures 总被引:1,自引:0,他引:1
Jozef Nahálka Peter Blanárik Peter Gemeiner Eva Matúsova Ivana Partlová 《Biotechnology letters》1996,18(12):1453-1458
Summary Optimal conditions for the growth of Drosophyllum lusitanicum Link. in suspension culture and for the production of plumbagin (5-hydroxy-2-methyl-3,4-naphthoquinone) were pH 3.5 with 10 g sucrose/l. 相似文献
130.