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81.
Long non-coding RNAs (lncRNAs), which are longer than >?200 nt, perform various functions in a variety of important biological processes. The aim of this study is the investigation of relative expression levels of AK372815 putative pyridoxal reductase (PLR) gene and sense lncRNA AK370814 on four barley genotypes (Hasat, Beysehir 99, Konevi 98 and Tarm 92) in response to 150 mM salinity application during 3 days post-germination. Seeds were placed randomly in petri dishes containing (a) only H2O (control), (b) 150 mM NaCl, for 72 h. RNA isolation was carried out using TriPure® reagent from 150 mM salt-treated root and shoot samples. Relative expression levels of AK372815 PLR and sense lncRNA AK370814 were determined by qPCR. Results demonstrated that salinity affected the expression levels of both AK372815 PLR gene and sense lncRNA AK370814 during germination. Although expression levels of AK372815 PLR tended to be down-regulated under salinity, expression levels of sense lncRNA AK370814 were up-regulated. Another goal of this study is improvement of alternative approach to NGS technologies for determination of relative expression levels of sense lncRNAs under particular circumstances. This is the first report that demonstrates a relationship between lncRNA and vitamin B6 salvage pathway.  相似文献   
82.
Globally, forests are of great economic importance and play a vital role in maintaining friendly ecological environments, sustainability of eco-systems, and biodiversity. Harsh environments, human activities and climate warming have long threatened the diversity of forest genetic resources. Among all conservation strategies, cryopreservation is at present time considered an ideal means for long-term conservation of plant genetic resources. To date, studies on cryopreservation of forest trees have been far behind agricultural and horticultural crops. The present review provides a comprehensive and update information on recent advances in cryopreservation of shoot tips, somatic embryogenic callus and seeds of forest trees. Assessments of genetic stability in the regenerants following cryopreservation were also analyzed and addressed. Further studies on cryopreservation of forest trees are proposed and needed. By doing so, we expect to re-evoke research interests and promote further developments in forest tree cryobiotechnology, thus assisting to ensure maintenance of biodiversity of genetic resources of forest trees.  相似文献   
83.
Two new species of the mite genus Zercon C. L. Koch, 1836 have been found: Zercon ekizi sp. n. and Zercon emirdagicus sp. n. are described and illustrated from female specimens collected in Afyonkarahisar and Kütahya provinces, Turkey. The similarities and differences between the related species are discussed.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:7388D199-2D1D-49F7-9747-4F49E8810067  相似文献   

84.
85.
Mounting evidence suggests involvement of deregulated microRNA (miRNA) expression during the complex events of tumorigenesis. Among such deregulated miRNAs in cancer, miR-125b expression is reported to be consistently low in breast cancers. In this study, we screened a panel of breast cancer cell lines (BCCLs) for miR-125b expression and detected decreased expression in 14 of 19 BCCLs. Due to the heterogeneity of breast cancers, MCF7 cells were chosen as a model system for ERBB2 independent breast cancers to restore miR-125b expression (MCF7-125b) to investigate the phenotypical and related functional changes. Earlier, miR-125b was shown to regulate cell motility by targeting ERBB2 in ERBB2 overexpressing breast cancer cells. Here we showed decreased motility and migration in miR-125b expressing MCF7 cells, independent of ERBB2. MCF7-125b cells demonstrated profoundly decreased cytoplasmic protrusions detected by phalloidin staining of filamentous actin along with decreased motility and migration behaviors detected by in vitro wound closure and transwell migration assays compared to empty vector transfected cells (MCF7-EV). Among possible numerous targets of miR-125b, we showed ARID3B (AT-rich interactive domain 3B) to be a novel target with roles in cell motility in breast cancer cells. When ARID3B was transiently silenced, the decreased cell migration was also observed. In light of these findings, miR-125b continues to emerge as an interesting regulator of cancer related phenotypes.  相似文献   
86.
The effect of configuration of activated sludge systems on heavy metal toxicity was investigated. Two bench-scale completely mixed activated sludge systems were operated identically in order to determine the toxic effects of Cr(VI), Zn(II) and industrial wastewater on the activated sludge biomass. One system was operated with an aerobic selector and the other without. Batch experiments based on OECD 209 (Organisation for Economic Cooperation and Development) were performed using a respirometer to find out potential toxicity reduction effect of an aerobic selector. The IC50 (concentration of a chemical that exhibits 50% respiration inhibition) values of Cr(VI), Zn(II) and industrial wastewater in the activated sludge were determined. Results indicated that the heavy metals and industrial wastewater caused less inhibitory effect on the selector activated sludge system in comparison to the conventional activated sludge system. Cr(VI) was found to exert higher inhibition on both systems.  相似文献   
87.

Purpose

Migraine is a multifactorial and complex disorder, and any clear diagnostic marker to assess the status of the migraineurs has not been established, yet. Nonsteroidal anti-inflammatory drugs reduce production of prostanoids including PGE2 by inhibiting COX-1 and/or COX-2, and thereby suppress inflammatory pain in patients suffering from rheumatoid arthritis, osteoarthritis, and migraine. Thus, COX-2 regulation is important in the pathogenesis and treatment of migraine. We prospectively investigated COX-2-765G → C and COX-2-1195A → G gene polymorphisms which may account for an increased risk of migraine.

Methods

The present analyses are based on 144 case subjects with migraine disease and 123 non-case subjects. Genotyping of COX-2 gene polymorphisms (COX-2-765G → C, COX-2-1195A → G) was detected by PCR-RFLP.

Results

We, for the first time, demonstrated positive association of COX-2 gene variants with an increased risk for development of migraine. Carriers of COX-2-765 C + genotype in controls were higher than in the patients (57.7% and 36.1% respectively; P < 0.0001) and the frequencies of G + genotype in patients were higher than in the controls (97.9% and 88.6% respectively; P: 0.002). In addition, frequencies of COX-2-765 GG and GC genotypes in patients were higher than in the controls (P < 0.0001, P < 0.0001 respectively). It seems that COX-2-765 G + genotype had increased and COX-2-765 C + genotype had decreased risk for migraine. In COX-2-1195 polymorphism only AG genotype was statistically significantly different in patients than in the controls (P < 0.05).

Conclusions

Our findings have suggested that COX-2-765 G + genotype could facilitate the development of migraine disease.  相似文献   
88.
Phytoplankton species vary in their physiological properties, and are expected to respond differently to seasonal changes in water column conditions. To assess these varying distribution patterns, we used 412 samples collected monthly over 12 years (1991–2004) at the Bermuda Atlantic Time-Series Study site, located in the northwestern Sargasso Sea. We measured plastid 16S ribosomal RNA gene abundances with a terminal restriction fragment length polymorphism approach and identified distribution patterns for members of the Prymnesiophyceae, Pelagophyceae, Chrysophyceae, Cryptophyceae, Bacillariophyceae and Prasinophyceae. The analysis revealed dynamic bloom patterns by these phytoplankton taxa that begin early in the year, when the mixed layer is deep. Previously, unreported open-ocean prasinophyte blooms dominated the plastid gene signal during convective mixing events. Quantitative PCR confirmed the blooms and transitions of Bathycoccus, Micromonas and Ostreococcus populations. In contrast, taxa belonging to the pelagophytes and chrysophytes, as well as cryptophytes, reached annual peaks during mixed layer shoaling, while Bacillariophyceae (diatoms) were observed only episodically in the 12-year record. Prymnesiophytes dominated the integrated plastid gene signal. They were abundant throughout the water column before mixing events, but persisted in the deep chlorophyll maximum during stratified conditions. Various models have been used to describe mechanisms that drive vernal phytoplankton blooms in temperate seas. The range of taxon-specific bloom patterns observed here indicates that different ‘spring bloom'' models can aptly describe the behavior of different phytoplankton taxa at a single geographical location. These findings provide insight into the subdivision of niche space by phytoplankton and may lead to improved predictions of phytoplankton responses to changes in ocean conditions.  相似文献   
89.
A hundred and seventeen antibiotic-resistant Escherichia coli strains were isolated from public tap and spring waters which were polluted by fecal coliforms. There were no significant differences between two water sources as to the coliform pollution level (p> 0.05). All E. coli isolates were detected to be resistant to one or more antibiotics tested. Nearly 42% of the isolates showed multiresistant phenotype. Three (2.5%) of these isolates contained class 1 integron. Sequencing analysis of variable regions of the class 1 integrons showed two gene cassette arrays, dfr1-aadA1 and dhfrA17-aadA5. Resistance to ampicillin, tetracycline or trimethoprim-sulfamethoxazole was transferable according to the results of conjugation experiments. The rate of tetracycline resistance was 15%. tet(A)-mediated tetracycline resistance was widespread among tetracycline-resistant E. coli isolates. Genotyping by BOX-polymerase chain reaction (BOX-PCR) showed that some of the strains were epidemiologically related. This is the first report on the prevalence and characterization of class 1 integron-containing E. coli isolates of environmental origin in Turkey.  相似文献   
90.
Cisplatin is one of the most active cytotoxic agents in the treatment of cancer. High doses of cisplatin have also been known to produce hepatotoxicity. Several studies suggest that supplementation with an antioxidant can influence cisplatin-induced hepatotoxicity. The present study was designed to determine the effects of cisplatin on the liver oxidant/antioxidant system, and the possible protective effects of caffeic acid phenethyl ester (CAPE) on liver toxicity induced by cisplatin. Twenty-four adult female Wistar albino rats were divided into four groups of six rats each: control, cisplatin, CAPE, and cisplatin+CAPE. Cisplatin and CAPE were injected intraperitoneally. Liver tissue was removed to study the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), myeloperoxidase (MPO), xanthine oxidase (XO), adenosine deaminase (ADA), and the levels of malondialdehyde and nitric oxide (NO). The activities of SOD and GSH-Px increased in the cisplatin+CAPE and CAPE groups compared with the cisplatin group. CAT activity was higher in the cisplatin +CAPE group than the other three groups. XO activity was lower in the cisplatin group than the control group. MPO activity was also increased in the cisplatin group compared to the control and CAPE groups. It can be concluded that CAPE may prevent cisplatin-induced oxidative changes in liver by strengthening the antioxidant defence system by reducing reactive oxygen species and increasing antioxidant enzyme activities.  相似文献   
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