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121.
Ayşegül Akpinar Hülya Arslan Serap Kırmızı Ümran Seven Erdemİr Şeref Güçer 《International journal of phytoremediation》2015,17(6):546-555
Verbascum olympicum Boiss. (Scrophulariaceae) were studied as a candidate plant for remediating the Ni polluted soils. The metabolic responses, such as nitrate assimilation (nitrate reductase and glutamine synthetase activity) and antioxidant system activity [superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity], of this species exposed to nickel in Hoagland's nutrient medium were investigated as remediation performance parameters. The accumulation of nickel and the variations in the content of some elements (B, Cu, Fe, Mg, Mn, Mo and Zn) and some growth parameters, such as the water content, biomass production, and contents of chlorophyll and soluble protein, were also examined. The accumulation of Ni in both the roots and leaves varied depending on the exposure times and doses. Increased oxidative stress was suggested by the increases in the activities of SOD, CAT and APX. Although some element contents were inhibited by Ni treatments, these inhibitory effects was decreased depending on the time, and even these elements are accumulated in roots. These results are the novelties in the use of this species in biotechnology. 相似文献
122.
Nitrate reductase activity (NRA) in different compartments (leaves, inflorescence stalks, flowers and tuberous roots) of Asphodelus aestivus Brot. (Liliaceae) and actual mineral nitrogen (NO3−-N and NH4+-N) in soil surrounding the roots were investigated over one year. Although the highest NRA was found in the leaves, the other plant compartments, such as flowers and tuberous roots, also have nitrate assimilation capacity. High nitrate assimilation capacity under suitable conditions is considered to be a good strategy for development and dominance of this species in Mediterranean environments. There was a seasonal variation in nitrate assimilation in leaves and actual NO3−-N content of soils. Depending on actual nitrate content of soils, nitrate assimilation increased in winter. 相似文献
123.
We investigated the germination requirements of the species Stachys germanica L. subsp. bithynica (Boiss.) Bhattacharjee (Lamiaceae). We studied the effects of scarification, short-time moist chilling (+4 °C) for 15 and 30 days, and various doses of gibberellic acid (GA3; 0, 100, 150 and 250 ppm), Kinetin (KIN; 50 ppm) and a combination of 250 ppm GA3 and 50 ppm KIN. The hormone and moist chilling treatments were carried out under both continuous darkness (20 °C) and photoperiodic (20/10 °C; 12/12 h, respectively) conditions. Seeds failed to germinate in response to short-time moist chilling treatments with distilled water under both continuous darkness and photoperiodic conditions. Seeds were found to have dormancy. Treatments with GA3 or a combination of GA3 and KIN were successful at breaking seed dormancy. A maximum of 37% of the seeds germinated after GA3 application in all series. When only KIN was applied at a 50 ppm concentration, germination (12%) was found only with moist chilling for 30 days under continuous darkness. The highest germination rates were found in seeds treated with combination of 250 ppm GA3 and 50 ppm KIN. In the combination treatments, while the moist chilling treatments for 15 days resulted in 68 and 73% germination, respectively, these rates were up to 95% in the moist chilling treatments for 30 days under continuous darkness and photoperiodic conditions. Mean germination time (MGT) in GA3 and KIN combinations was lower than in other treatments. Scarification with 80% sulphuric acid did not promote germination. The characteristics of physiological dormancy of S. germanica ssp. bithynica seeds are consistent with conditions of existence in the in alpine habitat of this species. 相似文献
124.
Sengezer-Inceli M Murathanoglu O Castillo SS Sancar-Bas S Kaptan E 《Acta biologica Hungarica》2011,62(4):349-360
The role of prolactin in the regulation of frog skin functions is still unclear particularly during environmental changes. In this study, prolactin receptor (PRLR) was detected in active and hibernating frog dorsal skin using immunohistochemical method. PRLR immunoreactivity in active frogs was observed in the epidermis, in the secretory epithelium of granular glands and the secretory channel cells of the glands. Myoepithelial cells of granular glands that started accumulating secretory material or those with a full lumen were PRLR immunoreactive, while some myoepithelial cells of empty granular glands were negative for PRLR. In hibernating frogs, this immunoreactivity was observed in the same regions; however, immunoreactivity was more intense than that in active frogs. PCNA was employed for detection of proliferative activity of PRL in the dorsal skin, and immunoreactivity was detected in the nuclei of a few epidermis cells and in the duct of glands of active frogs. The number of immunoreactive nuclei in these regions increased in hibernating and in prolactin injected groups. We conclude that prolactin provides morphological and functional integrity of skin stimulating the proliferation and regulating the function of granular glands and plays an important role in the adaptation of amphibians to the long winter period. 相似文献
125.
In vitro culture is an important aid for ex situ conservation of rare, endemic or threatened plants. In this work, we establish an efficient method for the seed germination,
seedling development, and axillary shoot propagation of Centaurea zeybekii Wagenitz. The seeds, collected from a wild population, were surface sterilised and cultured on various in vitro germination media. The effects of photoperiod and temperature on seed germination were also investigated. Germinations were
obtained after 6 weeks in culture and the radicle emergence was evaluated as a main indicator. A high frequency of germination
was obtained on distilled water supplemented with vitamines and 1 mg/L GA3. Although the seed germination frequencies were not affected by photoperiod, the highest germination frequency was obtained
at 24 ± 2°C. A high frequency of axillary shoot proliferation was produced on MS medium supplemented with 1 mg/L BA. Then,
the axillary shoots were separated and transferred to MS medium with or without plant growth regulators for rooting. Rhizogenezis
was promoted after 6 weeks only in MS and 1/2 MS media containing 0.5 mg/L IBA. The rooting process was very slow and the
percentage of shoot rooting was also very low (15%).
The present study not only enables reinforcement of wild plant populations using ex situ growth of individuals, but it also helps to large number of aseptic seedling to use it in clonaly micropropagation studies. 相似文献
126.
Mitochondrial barcodes are diagnostic of shared refugia but not species in hybridizing oak gallwasps
Mitochondrial DNA barcodes provide a simple taxonomic tool for systematic and ecological research, with particular benefit for poorly studied or species-rich taxa. Barcoding assumes genetic diversity follows species boundaries; however, many processes disrupt species-level monophyly of barcodes leading to incorrect classifications. Spatial population structure, particularly when shared across closely related and potentially hybridizing taxa, can invalidate barcoding approaches yet few data exist to examine its impacts. We test how shared population structure across hybridizing species impacts upon mitochondrial barcodes by sequencing the cytochrome b gene for 518 individuals of four well-delimited Western Palaearctic gallwasp species within the Andricus quercuscalicis species group. Mitochondrial barcodes clustered individuals into mixed-species clades corresponding to refugia, with no difference in within- and between-species divergence. Four nuclear genes were also sequenced from 4 to 11 individuals per refugial population of each species. Multi-locus analyses of these data supported established species, with no support for the refugial clustering across species seen in mitochondrial barcodes. This pattern is consistent with mitochondrial introgression among populations of species sharing the same glacial refugium, such that mitochondrial barcodes identify a shared history of population structure rather than species. Many taxa show phylogeographic structure across glacial refugia, suggesting that mitochondrial barcoding may fail when applied to other sets of co-distributed, closely related species. Robust barcoding approaches must sample extensively across population structure to disentangle spatial from species-level variation. Methods incorporating multiple unlinked loci are also essential to accommodate coalescent variation among genes and provide power to resolve recently diverged species. 相似文献
127.
128.
Insect-borne diseases exact a high public health burden and have a devastating impact on livestock and agriculture. To date, control has proved to be exceedingly difficult. One such disease that has plagued sub-Saharan Africa is caused by the protozoan African trypanosomes (Trypanosoma species) and transmitted by tsetse flies (Diptera: Glossinidae). This presentation describes the biology of the tsetse fly and its interactions with trypanosomes as well as its symbionts. Tsetse can harbor up to three distinct microbial symbionts, including two enterics (Wigglesworthia glossinidia and Sodalis glossinidius) as well as facultative Wolbachia infections, which influence host physiology. Recent investigations into the genome of the obligate symbiont Wigglesworthia have revealed characteristics indicative of its long co-evolutionary history with the tsetse host species. Comparative analysis of the commensal-like Sodalis with free-living enterics provides examples of adaptations to the host environment (physiology and ecology), reflecting genomic tailoring events during the process of transitioning into a symbiotic lifestyle. From an applied perspective, the extensive knowledge accumulated on the genomic and developmental biology of the symbionts coupled with our ability to both express foreign genes in these microbes in vitro and repopulate tsetse midguts with these engineered microbes now provides a means to interfere with the host physiological traits which contribute to vector competence promising a novel tool for disease management. 相似文献
129.
RE Symula JS Beadell M Sistrom K Agbebakun O Balmer W Gibson S Aksoy A Caccone 《PLoS neglected tropical diseases》2012,6(7):e1728
Trypanosoma brucei rhodesiense (Tbr) and T. b. gambiense (Tbg), causative agents of Human African Trypanosomiasis (sleeping sickness) in Africa, have evolved alternative mechanisms of resisting the activity of trypanosome lytic factors (TLFs), components of innate immunity in human serum that protect against infection by other African trypanosomes. In Tbr, lytic activity is suppressed by the Tbr-specific serum-resistance associated (SRA) protein. The mechanism in Tbg is less well understood but has been hypothesized to involve altered activity and expression of haptoglobin haemoglobin receptor (HpHbR). HpHbR has been shown to facilitate internalization of TLF-1 in T.b. brucei (Tbb), a member of the T. brucei species complex that is susceptible to human serum. By evaluating the genetic variability of HpHbR in a comprehensive geographical and taxonomic context, we show that a single substitution that replaces leucine with serine at position 210 is conserved in the most widespread form of Tbg (Tbg group 1) and not found in related taxa, which are either human serum susceptible (Tbb) or known to resist lysis via an alternative mechanism (Tbr and Tbg group 2). We hypothesize that this single substitution contributes to reduced uptake of TLF and thus may play a key role in conferring serum resistance to Tbg group 1. In contrast, similarity in HpHbR sequence among isolates of Tbg group 2 and Tbb/Tbr provides further evidence that human serum resistance in Tbg group 2 is likely independent of HpHbR function. 相似文献
130.
Meltem Yolal Serap Basoglu Hakan Bektas Serpil Demirci Sengul Alpay-Karaoglu Ahmet Demirbas 《Russian Journal of Bioorganic Chemistry》2012,38(5):539-549
3-Fluoro-4-(4-phenylpiperazin-l-yl)aniline (II) prepared from 3,4-difluoro nitrobenzene was converted to the corresponding Schiff bases (III) and (IV) by treatment with 4-methoxybenzaldehyde and indol-3-carbaldehyde, respectively. Treatment of amine (II) with 4-fluorophenyl isothiocyanate afforded the corresponding thiourea derivative (V). Compound (V) was converted to thiazolidinone and thiazoline derivatives (VI) and (VII) by cyclocondensation with ethylbromoacetate or 4-chlorophenacylbromide, respectively. The synthesis of carbothioamide derivative (X) was performed starting from compound (II) by three steps. Treatment of compound (X) with sodium hydroxide, sulfuric acid, or chlorophenacyl bromide generated the corresponding 1,2,4-triazole (XI), 1,3,4-thiadiazole (XII), and 1,3-thiazolidinone (XIII) derivatives, respectively. The structural assignments of new compounds were based on their elemental analysis and spectral (IR, 1H-NMR, 13C-NMR, and LC-MS) data. In the antimicrobial activity study all the compounds revealed high anti-Mycobacterium smegmatis activity. 相似文献