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171.
Uday Veer Singh Amar Abhishek Monika Bhaskar Neeraj Tandan Nasreen Ghazi Ansari Netra Pal Singh 《Bioinformation》2015,11(3):138-144
In this study, distribution of metal accumulation and their biological changes of Indian mustard plants (Brassica nigra L.) grown in
soil irrigated with different concentration of rayon grade paper effluent (RGPE, 25%, 50%, 75%, 100%, v/v) were studied. A
pronounced effect was recorded at 50% (v/v) RGPE on germination of seeds, amylase activity and other growth parameters in
Indian mustard plants. An increase in the chlorophyll and protein contents was also recorded at <50% (v/v) RGPE followed by a
decrease at higher concentrations of RGPE (>75%). A significant increase lipid peroxidation was recorded, which was evidenced by
the increased malondialdehyde (MDA) content in shoot, leaves and seeds in tested plant at all the concentrations of RGPE. This
Indian mustard plants (Brassica nigra L.) are well adapted for tolerance of significant amount of heavy metals due to increased level
of antioxidants (cysteine and ascorbic acid) in root shoot and leaves of treated plants at all concentration of RGPE. Moreover, it is
also important that RGPE should be treated to bring down the metal concentration well within the prescribed limit prior to use in
agricultural soil for ferti-irrigation. 相似文献
172.
微藻的闪光效应可以大幅提高微藻的光效率,提高微藻产量。通过在传统的板式光生物反应器中加入斜挡板以增强微藻的闪光效应。以小球藻为模型藻种,考察了新型板式光生物反应器内不同光强和不同进口流速对小球藻生长速率和光效率的影响。结果表明,当进口流速为0.16 m/s时,随着光强的提高,小球藻的细胞浓度逐渐增加,光效率逐渐降低;在500μmol/(m2·s)的光强条件下,小球藻细胞浓度和光效率均随着进口流速的提高而增加。新型板式光生物反应器内小球藻的细胞浓度比传统板式光生物反应器提高了39.23%,表明在传统板式光生物反应器内加入斜挡板可有效增强微藻的闪光效应。 相似文献
173.
Hee-Kyung Ahn Yong Won Kang Hye Min Lim Inhwan Hwang Hyun-Sook Pai 《Molecules and cells》2015,38(10):866-875
COPI vesicles are essential to the retrograde transport of proteins in the early secretory pathway. The COPI coatomer complex consists of seven subunits, termed α-, β-, β′-, γ-, δ-, ε-, and ζ-COP, in yeast and mammals. Plant genomes have homologs of these subunits, but the essentiality of their cellular functions has hampered the functional characterization of the subunit genes in plants. Here we have employed virus-induced gene silencing (VIGS) and dexamethasone (DEX)-inducible RNAi of the COPI subunit genes to study the in vivo functions of the COPI coatomer complex in plants. The β′-, γ-, and δ-COP subunits localized to the Golgi as GFP-fusion proteins and interacted with each other in the Golgi. Silencing of β′-, γ-, and δ-COP by VIGS resulted in growth arrest and acute plant death in Nicotiana benthamiana, with the affected leaf cells exhibiting morphological markers of programmed cell death. Depletion of the COPI subunits resulted in disruption of the Golgi structure and accumulation of autolysosome-like structures in earlier stages of gene silencing. In tobacco BY-2 cells, DEX-inducible RNAi of β′-COP caused aberrant cell plate formation during cytokinesis. Collectively, these results suggest that COPI vesicles are essential to plant growth and survival by maintaining the Golgi apparatus and modulating cell plate formation. 相似文献
174.
175.
G?k?e Güllü Irem Peker Aptullah Haholu Fatih Eren Zafer Kü?ükodaci Bülent Güle? Hüseyin Baloglu Can Erzik Ayse ?zer Mustafa Akkiprik 《Genetics and molecular biology》2015,38(1):21-29
The functional role of IGFBP5 in breast cancer is complicated. Experimental and
bioinformatics studies have shown that IGFBP5 is targeted by miR-140-5p and miR-193b,
although this has not yet been proven in clinical samples. The aim of this study was
to evaluate the expression of miR-140-5p and miR-193b in breast cancer and adjacent
normal tissue and assess its correlation with IGFBP5 and the clinicopathological
characteristics of the tumors. IGFBP5 protein expression was analyzed
immunohistochemically and IGFBP5, miR-140 and miR-193b mRNA expression levels were
analyzed with real-time RT-PCR. Tumor tissue had higher miR-140-5p expression than
adjacent normal tissue (p = 0.015). Samples with no immunohistochemical staining for
IGFBP5 showed increased miR-140-5p expression (p = 0.009). miR-140-5p expression was
elevated in invasive ductal carcinomas (p = 0.002), whereas basal-like tumors had
decreased expression of miR-140-5p compared to other tumors (p = 0.008). Lymph
node-positive samples showed an approximately 13-fold increase in miR-140-5p
expression compared to lymph node-negative tissue (p = 0.049). These findings suggest
that miR-140-5p, but not miR-193b, could be an important determinant of IGFBP5
expression and clinical phenotype in breast cancer patients. Further studies are
needed to clarify the expressional regulation of IGFBP5 by miR-140-5p. 相似文献
176.
《Arthropod Structure & Development》2015,44(5):455-467
Sternal pores are important features for identification of male thrips, especially within the subfamily Thripinae. They vary in shape, size and distribution even between species of one genus. Their functional role is speculated to be that of sex- and/or aggregation pheromone production. Yet, sexual aggregations are not reported in Echinothrips americanus, known to have sternal pores, while we observed aggregations in Megalurothrips sjostedti, previously reported to lack them.We examined the sternal glands and pores of the thripine species E. americanus and M. sjostedti males, in comparison with those of Frankliniella occidentalis using light microscopy, as well as scanning and transmission electron microscopy. Pore plates of F. occidentalis were ellipsoid and medial on sternites III–VII, while in E. americanus they were distributed as multiple micro pore plates on sternites III–VIII. In M. sjostedti they appeared as an extremely small pore in front of the posterior margin of each of sternites IV–VII. Pore plate and pore plate area were distributed similarly on sternites III–VII in F. occidentalis. However, in E. americanus the total pore plate area increased significantly from sternites III to VIII. Ultrastructure of cells associated with sternal glands showed typical characteristics of gland cells that differ in size, shape and number. The function of sternal glands is further discussed on the basis of morphological comparisons with other thrips species. 相似文献
177.
Gergely Groma Ivan Grskovic Sylvia SchaelHarald W.A. Ehlen Raimund Wagener Amanda FosangAttila Aszodi Mats Paulsson Bent Brachvogel Frank Zaucke 《Matrix biology》2011,30(4):275-280
The two aggrecanases ADAMTS-4 and ADAMTS-5 have been shown to not only play roles in the breakdown of cartilage extracellular matrix in osteoarthritis, but also mediate processing of matrilins in the secretory pathway. The matrilins are adaptor proteins with a function in connecting fibrillar and network-like components in the cartilage extracellular matrix. Cleavage resulting in processed matrilins with fewer ligand-binding subunits could make these less efficient in providing matrix cohesion. In this study, the processing and degradation of matrilin-4 during cartilage remodeling in the growth plate of the developing mouse long bones were studied in greater detail. We show that ADAMTS-5 and a matrilin-4 neoepitope, revealed upon ADAMTS cleavage, colocalize in prehypertrophic/hypertrophic chondrocytes while they are not detected in proliferating chondrocytes of the growth plate. ADAMTS-5 and the cleaved matrilin-4 are preferentially detected in vesicles derived from the Golgi apparatus. The matrilin-4 neoepitope was not observed in the growth plate of ADAMTS-5 deficient mice. We propose that in the growth plate ADAMTS-5, and not ADAMTS-4, has a physiological function in the intracellular processing of matrilins and potentially of other extracellular matrix proteins. 相似文献
178.
Endothelial dysfunction is associated with increase in oxidative stress and low NO bioavailability. The endothelial NO synthase (eNOS) uncoupling is considered an important factor in endothelial cell oxidative stress. Under increased oxidative stress, the eNOS cofactor tetrahydrobiopterin (BH4) is oxidized to dihydrobiopterin, which competes with BH4 for binding to eNOS, resulting in eNOS uncoupling and reduction in NO production. The importance of the ratio of BH4 to oxidized biopterins versus absolute levels of total biopterin in determining the extent of eNOS uncoupling remains to be determined. We have developed a computational model to simulate the kinetics of the biochemical pathways of eNOS for both NO and O2•− production to understand the roles of BH4 availability and total biopterin (TBP) concentration in eNOS uncoupling. The downstream reactions of NO, O2•−, ONOO−, O2, CO2, and BH4 were also modeled. The model predicted that a lower [BH4]/[TBP] ratio decreased NO production but increased O2•− production from eNOS. The NO and O2•− production rates were independent above 1.5 μM [TBP]. The results indicate that eNOS uncoupling is a result of a decrease in [BH4]/[TBP] ratio, and a supplementation of BH4 might be effective only when the [BH4]/[TBP] ratio increases. The results from this study will help us understand the mechanism of endothelial dysfunction. 相似文献
179.
A laboratory-scale anaerobic-anoxic-oxic (AAO) system was established to investigate the fate of DnBP. A removal kinetic model including sorption and biodegradation was formulated, and kinetic parameters were evaluated with batch experiments under anaerobic, anoxic, oxic conditions. However, it is highly complex and is difficult to confirm the kinetic parameters using conventional mathematical modeling. To correlate the experimental data with available models or some modified empirical equations, an artificial neural network model based on multilayered partial recurrent back propagation (BP) algorithm was applied for the biodegradation of DnBP from the water quality characteristic parameters. Compared to the kinetic model, the performance of the network for modeling DnBP is found to be more impressive. The results showed that the biggest relative error of BP network prediction model was 9.95%, while the kinetic model was 14.52%, which illustrates BP model predicting effluent DnBP more accurately than kinetic model forecasting. 相似文献
180.