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Background
The Blood Brain Barrier (BBB) maintains the homeostasis of central nervous system by preventing the free passage of macromolecules from the systemic circulation into the brain. This normal physiological function of the BBB presents a challenge for delivery of therapeutic compounds into the brain. Recent studies have shown that the application of focused ultrasound together with ultrasound contrast agent (microbubbles) temporarily increases the permeability of the BBB. This effect is associated with breakdown of tight junctions, the structures that regulate the paracellular permeability of the endothelial cell layer. The influence of this ultrasound effect on the activation of intracellular signaling proteins is currently not well understood. Therefore, the aim of this study was to investigate the activation of cell survival signaling molecules in response to ultrasound-mediated BBB opening; 相似文献154.
155.
Davood Shayegan Jalal Jalali Sendi Ahad Sahragard Arash Zibaee 《Physiological Entomology》2019,44(2):169-176
The present study investigates the effect of gibberellic acid (GA3), a terpenoid and phytohormone, on the digestive physiology and intermediary metabolism of the cotton bollworm Helicoverpa armigera Hübner (Lepidoptera, Noctuidae). Incorporation of GA3 (800 μg g?1 diet) in an artificial diet results in significant reductions in the rates of diet consumption and the efficiency of conversion of food consumption by by H. armigera larvae. The relative growth rate decreases as the concentration increases. The relative α‐amylase activity in sixth‐instar larvae of H. armigera decreases significantly after ingestion of four concentrations of GA3. Histological studies of the midgut in GA3‐treated larvae (800 μg g?1 diet) show degeneration of the epithelial cells. The alanine and aspartate aminotransferase activity decreases at the highest concentration. However, acid phosphatase, alkaline phosphatase, γ‐glutamyl transferase and lactate dehydrogenase activity increase significantly compared with the control. The results clearly demonstrate the adverse effects of GA3 on H. armigera via interruption of nutritional physiology and metabolism. 相似文献
156.
Yepuri Vijay Jalali Saakshi Kancharla Nagesh Reddy V. B. Arockiasamy S. 《Molecular biology reports》2020,47(7):5091-5099
Molecular Biology Reports - Jatropha curcas is a potential biodiesel crop and a highly adaptable species to various agro-climatic conditions. In this study, we have utilized transposable... 相似文献
157.
Five heavy metals (Cd, Cu, Ni, Pb, and Zn) in river sediments from Abshineh River, Hamedan, western Iran, were fractionated by a sequential extraction procedure. Cu, Ni, Pb, and Zn existed in sediments mainly in residual fraction (mean 92%, 86%, 77%, and 65%, respectively), whereas Cd occurred mostly as organic matter (mean 41%) and exchangeable (mean 25%) fractions. The mean percent of mobile fraction of Cd, Cu, Ni, Pb, and Zn in contaminated sediments was 25, 13, 4, 24, and 10, respectively, which suggests that the mobility and bioavailability of the five metals in sediments probably decline in the following order: Cd = Pb > Cu > Zn > Ni. The metal levels were also evaluated according to the contamination factor, which revealed significant anthropogenic pollution of Cd and Pb. 相似文献
158.
Abasalt Hosseinzadeh Colagar Fatemeh Shayanmehr Seyed Gholamali Jalali Habib Zare Nicholas P. Tippery 《分类学与生物多样性》2013,11(1):88-101
The taxonomy and phylogeny of Hyrcanian Alnus (eight taxa) were investigated using sequence data from the nuclear ribosomal ITS and the chloroplast trnH-psbA intergenic spacer. The mean nucleotide compositions of the ITS region were completely equal for two main Hyrcanian taxa, and the ITS1 region had fewer variable sites than the ITS2 region. Two relatively distinct types of ITS2 were identified for two main clades of Hyrcanian Alnus, the A. subcoradata complex and A. glutinosa. Two recently described species, A. dolichocarpa and A. djavanshirii, did not show any diagnostic sites and had a similar pattern with A. subcordata. Three recognized subspecies of A. glutinosa were distributed in the A. incana complex. In the analysis of trnH-psbA sequence data, the three subgenera of Alnus were poorly resolved relative to one another. Alnus glutinosa had minimal sequence divergence from A. incana and A. tenuifolia, and A. subcordata had a minimum distance from A. cordata and A. orientalis. A maximum pairwise distance also was observed between Hyrcanian species (A. glutinosa and A. subcordata) with A. pendula and A. sieboldiana, respectively. Ultimately, the molecular phylogeny of Alnus based on two DNA barcode markers was not congruent with recent morphological classifications, so additional DNA markers should be explored for identifying Alder taxa in the Hyrcanian forest. 相似文献