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61.
Sepideh Valimehr Forough Sanjarian Haleh Hashemi sohi Ali Sharafi Farzaneh Sabouni 《Physiology and Molecular Biology of Plants》2014,20(3):351-356
Nepeta pogonosperma is an important medicinal plant with anti-inflammatory effects. An efficient and reliable transformation system for this plant was developed through optimization of several factors which affected the rate of Agrobacterium rhizogenes mediated transformation. Five bacterial strains, A4, ATCC15834, LBA9402, MSU440 and A13, two explant types, leaves and stems, and several co-cultivation media were examined. The maximum rate of hairy root induction was obtained from stem explants using MSU440 and ATCC15834 bacterial strains. A drastic increase in the frequency of transformation (91 %) was observed when MS medium lacking NH4NO3, KH2PO4, KNO3 and CaCl2. Hairy root lines were confirmed by polymerase chain reaction (PCR) using primers of the rolB gene. According to Southern blot analysis, one T-DNA copy was inserted into each of the hairy root lines. In the present study, transgenic hairy roots have been obtained trough genetic transformation by A. rhizogenes harbouring two plasmids, the Ri plasmid and pBI121 binary vector harbouring gus reporter gene. Expression of the gus gene in transgenic hairy root was confirmed by histochemical GUS assay. 相似文献
62.
Kevin M. Wood Anisa Zeqja H. Frederik Nijhout Michael C. Reed Janet Best Parastoo Hashemi 《Journal of neurochemistry》2014,130(3):351-359
The neurotransmitter serotonin underlies many of the brain's functions. Understanding serotonin neurochemistry is important for improving treatments for neuropsychiatric disorders such as depression. Antidepressants commonly target serotonin clearance via serotonin transporters and have variable clinical effects. Adjunctive therapies, targeting other systems including serotonin autoreceptors, also vary clinically and carry adverse consequences. Fast scan cyclic voltammetry is particularly well suited for studying antidepressant effects on serotonin clearance and autoreceptors by providing real‐time chemical information on serotonin kinetics in vivo. However, the complex nature of in vivo serotonin responses makes it difficult to interpret experimental data with established kinetic models. Here, we electrically stimulated the mouse medial forebrain bundle to provoke and detect terminal serotonin in the substantia nigra reticulata. In response to medial forebrain bundle stimulation we found three dynamically distinct serotonin signals. To interpret these signals we developed a computational model that supports two independent serotonin reuptake mechanisms (high affinity, low efficiency reuptake mechanism, and low affinity, high efficiency reuptake system) and bolsters an important inhibitory role for the serotonin autoreceptors. Our data and analysis, afforded by the powerful combination of voltammetric and theoretical methods, gives new understanding of the chemical heterogeneity of serotonin dynamics in the brain. This diverse serotonergic matrix likely contributes to clinical variability of antidepressants.
63.
Shaghayegh Pezeshki Payam Hashemi Alireza Salimi Sheida Ebrahimi Mandana Javanzad Amir Monfaredan 《Reports of Biochemistry & Molecular Biology》2021,10(2):224
Background:Prostate cancer (PC) is one of the most abundant cancers among men, and In Iran, has been responsible for 6% of all deaths from cancer in men. NUF2 and GMNN genes are considered as loci of susceptibility to tumorigenesis in humans. Alterations in expression of these genes have been reported in various malignancies. The aim of our study was to test whether different NUF2 and GMNN expression levels are associated with PC incidence and hence, might be considered as new molecular tools for PC screening.Methods:Biopsy samples from 40 PC patients and 41 healthy Iranian men were used to determine the relative gene expression. After RNA extraction and cDNA synthesis, samples were analyzed using TaqMan Quantitative Real time PCR. Patients’ background information, included smoking habits and family histories of PC, were recorded. Stages and grades of their PC were classified by the TNM tumor, node, metastasis (TMN) staging system based on standard guidelines.Results:NUF2 expression did not significantly differ between the groups, while GMNN expression was significantly greater in the PC specimens than in the controls.Conclusion:Regarding the significant role of GMNN in various tumor phenotypes, and its importance in PC progression, the alteration in GMNN expression in PC samples vs. controls indicate that the genetic profiling of this cancer might be considered to personalize therapy for each patient in the future.Key Words: Family history, Geminin (GMNN), Tumor staging, NUF2, Prostate cancer 相似文献
64.
The Mouse GalR2 Galanin Receptor: Genomic Organization, cDNA Cloning, and Functional Characterization 总被引:1,自引:1,他引:1
Ling Pang Tanaz Hashemi Hu-Jung J. Lee Maureen Maguire Michael P. Graziano Marvin Bayne Brian Hawes Gwendolyn Wong Suke Wang 《Journal of neurochemistry》1998,71(6):2252-2259
Abstract: The diverse physiological actions of galanin are thought to be mediated through activation of galanin receptors (GalRs). We report the genomic and cDNA cloning of a mouse GalR that possesses a genomic structure distinct from that of GalR1 and encodes a functional galanin receptor. The mouse GalR gene consists of two exons separated by a single intron within the protein-coding region. The splicing site for the intron is located at the junction between the third transmembrane domain and the second intracellular loop. The cDNA encodes a 370-amino acid putative G protein-coupled receptor that is markedly different from human GalR1 and rat GalR3 (38 and 57%) but shares high homology with rat GalR2 (94%). In binding studies utilizing membranes from COS-7 cells transfected with mouse GalR2 cDNA, the receptor displayed high affinity ( K D = 0.47 n M ) and saturable binding with 125 I-galanin ( B max = 670 fmol/mg). The radioligand binding can be displaced by galanin and its analogues in a rank order: galanin ⋍ M40 ⋍ M15 ⋍ M35 ⋍ C7 ⋍ galanin (2–29) ⋍ galanin (1–16) ≫ galanin (10–29) ⋍ galanin (3–29), which resembles the pharmacological profile of the rat GalR2. Receptor activation by galanin in COS-7 cells stimulated phosphoinositide metabolism, which was not reversed by pertussis toxin. Thus, the galanin receptor encoded in the cloned mouse GalR gene is the type 2 galanin receptor and is active in both ligand binding and signaling assays. 相似文献
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67.
P R Ganz J S Atkins D S Palmer A K Dudani S Hashemi F Luison 《Biochemical and biophysical research communications》1991,180(1):231-237
Factor VIII and von Willebrand factor are two plasma proteins essential for effective hemostasis. In vivo, they form a non-covalent complex whose association appears to be metal ion dependent. However, a precise definition of the nature of the molecular forces governing their association remains to be defined, as does their binding affinity. In this paper we have determined the dissociation constant and stoichiometry for Factor VIII binding to immobilized von Willebrand factor. The data demonstrate that these proteins interact saturably and with relatively high affinity. Computer assisted analyses of the Scatchard data favour a two site binding model. The higher affinity site was found to have a Kd of 62 (+/- 13) x 10(-12) M while that of the lower affinity site was 380 (+/- 92) x 10(-12) M. The density of Factor VIII binding sites (Bmax) present on von Willebrand factor was 31 (+/- 3) pM for the high affinity binding site and 46 (+/- 6) pM for the lower site, corresponding to a calculated Factor VIII: von Willebrand factor binding ratio of 1:33 and 1:23, respectively. 相似文献
68.
Maryam Fard Maryam Akhavan-Tavakoli Sayeh Khanjani Sona Zare Haleh Edalatkhah Shaghayegh Arasteh Davood Mehrabani Amir-Hassan Zarnani Somaieh Kazemnejad Reza Shirazi 《Molecular biotechnology》2018,60(2):100-110
The skin provides a dynamic barrier separating and protecting human body from the exterior world, and then immediate repair and rebuilding of the epidermal barrier is crucial after wound and injury. Wound healing without scars and complete regeneration of skin tissue still remain as a clinical challenge. The demand to engineer scaffolds that actively promote regeneration of damaged areas of the skin has been increased. In this study, menstrual blood-derived stem cells (MenSCs) have been induced to differentiate into keratinocytes-like cells in the presence of human foreskin-derived keratinocytes on a bilayer scaffold based on amniotic membrane and silk fibroin. Based on the findings, newly differentiated keratinocytes from MenSCs successfully expressed the keratinocytes specific markers at both mRNA and protein levels judged by real-time PCR and immunostaining techniques, respectively. We could show that the differentiated cells over bilayer composite scaffolds express the keratinocytes specific markers at higher levels when compared with those cultured in conventional 2D culture system. Based on these findings, bilayer amniotic membrane/nano-fibrous fibroin scaffold represents an efficient natural construct with broad applicability to generate keratinocytes from MenSCs for stem cell-based skin wounds healing and regeneration. 相似文献
69.
4‐bp insertion/deletion (rs3783553) polymorphism within the 3′UTR of IL1A contributes to the risk of prostate cancer in a sample of Iranian population 下载免费PDF全文
70.
F1 hybrids obtained from crosses between the rubber-bearing species, Parthenium argentatum Gray (commonly known as guayule), and P. schottii Greenman ex Millspaugh and Chase, a nonrubber-producing species from southern Mexico, were morphologically variable. They were generally intermediate between the two species with respect to leaf size, head size, number of disk florets per head, and the length of the peduncles. Like the parental species, the hybrids had 2n = 36 chromosomes. They averaged 14.56 bivalents, 3.92 univalents, 0.56 trivalents, and 0.32 quadrivalents, indicating a high degree of homeology between the genomes of the two species. The observation of one quadrivalent at diakinesis in 32% of the PMCs and the frequent occurrence of a bridge accompanied by a fragment at late anaphase I of the F, hybrids suggested that the two species differ in a reciprocal translocation and a paracentric inversion. The ease of hybridization, the partial fertility of the hybrids, and their high degree of chromosome pairing indicate that P. schottii and P. argentatum are closely related in spite of their distinct morphological features and geographical distributions. This close relationship provides an opportunity to transfer genes from P. schottii to guayule for desirable characteristics, such as high biomass production and resistance to Verticillium dahliae Kleb, by means of interspecific hybridization. 相似文献