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601.
Many of the plants found in serpentine areas are endemics and they may accumulate Ni at high concentration. High accumulation of Cr is rare, or in some views, never properly demonstrated. Generally, a very small proportion of any serpentine flora shows high accumulation of Ni, in some serpentine areas Ni accumulators are completely absent. There are approximately 570 hyperaccumulator plant species found on earth, 450 of them are Ni hyperaccumulators. A few of the Ni accumulators have potential for phytoremediation or phytomining. In the present study, 19 different Brassicaceae members growing in serpentine habitats in the district of Yahyal?, Kayseri province, Turkey viz., members of genera Aethionema, Alyssum, Arabis, Heldreichia, Hesperis, Iberis, Isatis, Microthlaspi, Odontarrhena, Pseudosempervivum and Thlaspi were investigated. Nickel concentrations in the soil and underground and aboveground parts of plants were determined by using ICP-OES. It was observed that Ni concentrations of seven taxa (Odontarrhena muralis, O. oxycarpa, Isatis cappadocica subsp. cappadocica, Microthlaspi perfoliatum, Pseudosempervivum sempervivum, Thlaspi triangulare, Thlaspi rosulare) reach the threshold criterion of 1,000 mg kg?1 for Ni hyperaccumulation. In this study Ni concentrations in aboveground tissues of I. cappadocica subsp. cappadocica are determined as 5,587 mg kg?1 (in dry weight). Accordingly, it is suggested that this taxon be added to the list of Ni hyperaccumulator plants. 相似文献
602.
Triclosan (TCS), a chemical used for its antibacterial properties, is an ingredient in many detergents, soaps, deodorants, cosmetics, antimicrobial creams, toothpastes, and an additive in various plastics and textiles. The behavioral changes at different TCS concentrations (0.001–0.002–0.005–0.01–0.02–0.05–0.1–0.2–0.5 mg/L) were determined for the each test organisms in the study. The synthetic freshwater has temperature 20 ± 2°C, dissolved oxygen 7.0 ± 2 mg/L, pH 7.0–8.0. All experiments were replicated three times, in 14 h light, 10 h dark incubations, 10 fishes were put to each aquarium. In hourly and daily observations, times of dead and number for Poecilia reticulata, Danio rerio were recorded. Behavioral changes of Poecilia reticulata and Danio rerio were observed, such as fast-moving, uncontrolled swimming, trying to escape out of the water, vertical action to the water surface, loss of balance, respiratory difficulties, chills, and inversion. 相似文献
603.
Quorum sensing (QS) is a widespread mechanism utilized by both Gram (+) and Gram (?) bacteria for communication and regulation of specific virulence traits and phenotypes due to population density. Plants are known to produce a number of compounds that can inhibit this communication and most of them have been discovered through well-known Chromobacterium violaceum biomonitor strains assays. In this study, we have analyzed 36 extracts, from 26 Turkish plant species, for their effects on bacterial growth and inhibition or induction of QS in the said biomonitoring assay. Four of the crude plant extracts from Tanacetum balsamita L. subsp. balsamitoides (Compositaceae), Epilobium angustifolium L. (Onograceae), Quercus frainetto Ten. (Fagaceae) and Quercus robur L. (Fagaceae) showed QS inhibitory activity and significantly reduced violacein production in C. violaceum. Particularly, ethyl acetate soluble compounds extracted from leaves of Quercus spp. were efficient in QS inhibition without any apparent increase in bacterial growth. On the other hand, extracts from Mentha longifolia subsp. longifolia and Hypericum orientale showed enhanced violacein production, thus increasing QS-dependent behaviour. Our results clearly demonstrate the QS-inhibitory effects of Q. frainetto Ten., E. angustifolium and T. balsamita L. extracts, while two other species showed QS-inducing effects, for the first time. 相似文献
604.
Ayşen Melda Çolak 《Saudi Journal of Biological Sciences》2018,25(6):1242-1246
Not many chemical hormone studies does exist in our country especially in berry fruits. Foliar application of melatonin and gibberellic acid hormones was performed in 2016 and 2017 in order to analyze the effects of different doses of hormone applications on fruit quality and yield. Pheonologic, pomological and some bioactive content analyses of these hormones were studied. According to the research results, while M?+?GA10 ppm (240.50; 3.9) and M?+?GA 5?ppm (226.50; 3.6) applications have the highest fruit number and weight (g), the highest fruit size was obtained from GA 5?ppm (21.21?mm fruit length, 16.56?mm fruit width) and M 10?ppm (21.10?mm fruit length, 16.20?mm fruit width) chemical applications in Jumbo blackberry species. The highest values in Ph, soluble solid content (SSC) and titratable acidity averages were obtained from GA 5?ppm (3.69; 10.80; 2.42) and GA 10?ppm (3.68; 10.70; 2.40) applications; the highest total antioxidant activity in bioactive characteristics averages was found in G 10?ppm 143.21?mg/g, the highest total phenolics was identified in G 5?ppm 72.68?ppm/GAE and the highest total flavonoids was determined in G 10?ppm 4925.75?ppm/QE. 相似文献
605.
606.
İsmail Gökhan Deniz İlker Genç Ayşe Gül Ince Candan Aykurt Safinaz Elmasulu Hüseyin Sümbül Sahriye Sönmez Sedat Çitak 《Biologia》2013,68(3):373-383
The first specimens of Allium elmaliense were collected in Elmal? (Antalya/Turkey) in 2001 and were described as new species in 2004. However, Allium elmaliense was claimed as synonym of Allium cyrilli in 2006. This study was undertaken to reveal the differences between these taxa utilizing morphological, palynological, and chromosome characters and genomic differences based on the DNA analyses along with the ecological preference studies conducted during 2006 and 2011. The results clearly indicated differences between these two taxa in terms of morphological characters, pollen, seed surfaces and niche preferences. Chromosome morphology and Td-DAMD-PCR fingerprinting studies revealed that Allium elmaliense Deniz & Sümbül is a distinct species and not a synonym of A. cyrilli Ten. 相似文献
607.
Erkan Yula Toğrul Nagiyev Özlem Aycan Kaya Melek İnci M. Murat Çelik Fatih Köksal 《Folia microbiologica》2013,58(2):141-146
Helicobacter pylori was examined in 110 patients (82 (74.5) with gastritis, 18 (16.4) with duodenitis, six (5.5) with duodenal ulcer and gastroesophageal reflux, and four (3.6 %) with normal) with gastrointestinal problems living in rural area, no history of macrolide use, and detected by culture (71.8) or direct detection from gastric biopsies by PCR (82.7 %). Also, cagA gene was identified using PCR and was found positive in 68/91 (74.7 %) strains. The prevalence of clarithromycin-resistant H. pylori was investigated by two methods including PCR–RFLP (7.7 (A2142G 1.1 and A2143G 6.6 %)) and twofold agar dilution (8.9 %) to detect phenotypic and genotypic status simultaneously. Among all the H. pylori positive patients, eight (8.8 %) isolates were found to be resistant to clarithromycin by at least one of the AD and/or PCR–RFLP methods. H. pylori positive rates were significantly correlated with patients' sex, age, and endoscopic findings (p?=?0.040, <0.001 and <0.001, respectively). There were no differences in gender or endoscopic findings related to cagA + and cagA ? patients. The gene of cagA was not significantly helpful in predicting the clinical outcome of H. pylori infection alone. In conclusion, we revealed that there was a low prevalence of primer clarithromycin resistance in patients living in rural area with no history of macrolide use. The prevalence of mutant strains among the macrolide-resistant H. pylori varies even geographically between close provinces. 相似文献
608.
Yavuz Dodurga Yeşim Oymak Cumhur Gündüz N. Lale Satıroglu-Tufan Canan Vergin Nazan Çetingül Çığır Biray Avci Nejat Topçuoğlu 《Molecular biology reports》2013,40(4):3043-3048
The aim of the study is to the determine the profiles of cell cycle genes and a new candidate oncogene of URG4/URGCP which play role in leukemia, establishing the association between the early prognosis of cancer and the quantitation of genetic changes, and bringing a molecular approach to definite diagnosis. In this study, 36 newly diagnosed patients’ with ALL-AML in the range of 0–18 years and six control group patients’ bone marrow samples were included. Total RNA was isolated from samples and then complementary DNA synthesis was performed. The obtained cDNAs have been installed 96 well plates after prepared appropriate mixtures and assessed with LightCycler® 480 Real-Time PCR quantitatively. CHEK1, URG4/URGCP, CCNG1, CCNC, CDC16, KRAS, CDKN2D genes in the T-ALL group; CCND2, ATM, CDK8, CHEK1, TP53, CHEK2, CCNG2, CDK4, CDKN2A, E2F4, CCNC, KRAS genes in the precursor B-ALL group and CCND2, CDK6 genes in the AML group have shown significant increase in mRNA expression level. In the featured role of acute leukemia the regulating signaling pathways of leukemogenesis partially defined, although identification of new genetic markers in acute leukemia subgroups, will allow the development of early diagnostic and new treatment protocols. 相似文献
609.
Alper Özorak Mustafa Nazıroğlu Ömer Çelik Murat Yüksel Derviş Özçelik Mehmet Okan Özkaya Hasan Çetin Mehmet Cemal Kahya Seyit Ali Kose 《Biological trace element research》2013,156(1-3):221-229
The present study was designed to determine the effects of both Wi-Fi (2.45 GHz)- and mobile phone (900 and 1800 MHz)-induced electromagnetic radiation (EMR) on oxidative stress and trace element levels in the kidney and testis of growing rats from pregnancy to 6 weeks of age. Thirty-two rats and their 96 newborn offspring were equally divided into four different groups, namely, control, 2.45 GHz, 900 MHz, and 1800 MHz groups. The 2.45 GHz, 900 MHz, and 1,800 MHz groups were exposed to EMR for 60 min/day during pregnancy and growth. During the fourth, fifth, and sixth weeks of the experiment, kidney and testis samples were taken from decapitated rats. Results from the fourth week showed that the level of lipid peroxidation in the kidney and testis and the copper, zinc, reduced glutathione (GSH), glutathione peroxidase (GSH-Px), and total antioxidant status (TAS) values in the kidney decreased in the EMR groups, while iron concentrations in the kidney as well as vitamin A and vitamin E concentrations in the testis increased in the EMR groups. Results for fifth-week samples showed that iron, vitamin A, and β-carotene concentrations in the kidney increased in the EMR groups, while the GSH and TAS levels decreased. The sixth week results showed that iron concentrations in the kidney and the extent of lipid peroxidation in the kidney and testis increased in the EMR groups, while copper, TAS, and GSH concentrations decreased. There were no statistically significant differences in kidney chromium, magnesium, and manganese concentrations among the four groups. In conclusion, Wi-Fi- and mobile phone-induced EMR caused oxidative damage by increasing the extent of lipid peroxidation and the iron level, while decreasing total antioxidant status, copper, and GSH values. Wi-Fi- and mobile phone-induced EMR may cause precocious puberty and oxidative kidney and testis injury in growing rats. 相似文献
610.