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991.
Terrence L. Nicholson Ashfaq Mahmood Alan Davison Alun G. Jones 《Inorganica chimica acta》2011,365(1):484-486
The reaction of the Tc(I) complex [Tc(NO)Cl2(HOMe)(PPh3)2] with stoichiometric amounts of 2-mercatopyridine and a proton scavenger yields [Tc(NO)Cl(Spy)(PPh3)2] or [Tc(NO)(Spy)2(PPh3)], depending upon quantities of ligands employed. These two complexes have been structurally characterized. The small bite angles of the bidentate mercaptopyridine ligands cause significant deviation from octahedral coordination geometry. 相似文献
992.
Ahmadabad HN Hassan ZM Safari E Bozorgmehr M Ghazanfari T Moazzeni SM 《Cellular immunology》2011,269(2):90-95
Garlic is used all over the world for treatment of different diseases. A wide range of biological activities of garlic has been verified in vitro and in vivo. One of major proteins of garlic which has been isolated and purified is the 14 kDa protein. This protein has been shown to have immunomodulatory effects. In this study, the effect of the 14 kDa protein isolated from aged garlic extract (AGE) was investigated on maturation and immunomodulatory activity of dendritic cells (DC). Proteins were purified from AGE by biochemical method; the semi-purified 14 kDa protein was run on gel filtration Sephadex G50 and its purity was checked by SDS–PAGE. DC were isolated from spleen of BALB/c mice by Nycodenz centrifugation and their adhesiveness to plastic dish. 14 kDa protein from AGE was added to overnight culture of DC medium and the expression percentage of CD40, CD86, and MHC-II was evaluated by flowcytometric analysis. Also, proliferation of T-cells was measured by allogenic mixed lymphocyte reaction (MLR) test. The purified 14 kDa protein isolated from AGE increased the expression of CD40 molecule on DC, but it did not influence CD86 and MHCII molecules. Furthermore, no significant differences were noticed in the pulsed-DC with 14 kDa protein and non-pulsed DC on the MLR. 相似文献
993.
Adwan TS Ohm AM Jones DN Humphries MJ Reyland ME 《The Journal of biological chemistry》2011,286(41):35716-35724
PKCδ translocates into the nucleus in response to apoptotic agents and functions as a potent cell death signal. Cytoplasmic retention of PKCδ and its transport into the nucleus are essential for cell homeostasis, but how these processes are regulated is poorly understood. We show that PKCδ resides in the cytoplasm in a conformation that precludes binding of importin-α. A structural model of PKCδ in the inactive state suggests that the nuclear localization sequence (NLS) is prevented from binding to importin-α through intramolecular contacts between the C2 and catalytic domains. We have previously shown that PKCδ is phosphorylated on specific tyrosine residues in response to apoptotic agents. Here, we show that phosphorylation of PKCδ at Tyr-64 and Tyr-155 results in a conformational change that allows exposure of the NLS and binding of importin-α. In addition, Hsp90 binds to PKCδ with similar kinetics as importin-α and is required for the interaction of importin-α with the NLS. Finally, we elucidate a role for a conserved PPxxP motif, which overlaps the NLS, in nuclear exclusion of PKCδ. Mutagenesis of the conserved prolines to alanines enhanced importin-α binding to PKCδ and induced its nuclear import in resting cells. Thus, the PPxxP motif is important for maintaining a conformation that facilitates cytosplasmic retention of PKCδ. Taken together, this study establishes a novel mechanism that retains PKCδ in the cytoplasm of resting cells and regulates its nuclear import in response to apoptotic stimuli. 相似文献
994.
Mahmood F Hansen RH Agerholm-Larsen B Jensen KS Iversen HK Gehl J 《The Journal of membrane biology》2011,240(3):131-138
Clinical electroporation (EP) is a rapidly advancing treatment modality that uses electric pulses to introduce drugs or genes
into, e.g., cancer cells. The indication of successful EP is an instant plasma membrane permeabilization in the treated tissue.
A noninvasive means of monitoring such a tissue reaction represents a great clinical benefit since, in case of target miss,
retreatment can be performed immediately. We propose diffusion-weighted magnetic resonance imaging (DW-MRI) as a method to
monitor EP tissue, using the concept of the apparent diffusion coefficient (ADC). We hypothesize that the plasma membrane
permeabilization induced by EP changes the ADC, suggesting that DW-MRI constitutes a noninvasive and quick means of EP verification.
In this study we performed in vivo EP in rat brains, followed by DW-MRI using a clinical MRI scanner. We found a pulse amplitude–dependent
increase in the ADC following EP, indicating that (1) DW-MRI is sensitive to the EP-induced changes and (2) the observed changes
in ADC are indeed due to the applied electric field. 相似文献
995.
Muhammad?Arshad Rafiq Andreas?W. Kuss Lucia Puettmann Abdul Noor Annapoorani Ramiah Ghazanfar Ali Hao Hu Nadir?Ali Kerio Yong Xiang Masoud Garshasbi Muzammil?Ahmad Khan Gisele?E. Ishak Rosanna Weksberg Reinhard Ullmann Andreas Tzschach Kimia Kahrizi Khalid Mahmood Farooq Naeem Muhammad Ayub Kelley?W. Moremen John?B. Vincent Hans?Hilger Ropers Muhammad Ansar Hossein Najmabadi 《American journal of human genetics》2011,(2):348
996.
997.
998.
Khalid Mahmood Muhammad Bismillah Khan Muhammad Ijaz Ren Sen Zeng Shi Ming Luo 《Plant Growth Regulation》2014,74(1):73-82
This study examines allelopathic potential of genetically modified rice. The experiment was conducted on two isogenic lines Bacillus thuringiensis (Bt) and non-Bacillus thuringiensis (non-Bt). Both isogenic lines have same allelopathic ability before insect feeding and after limited insect feeding (Spodoptera litura) non-Bt rice genotype demonstrates more allelopathic potential. The S. litura cannot feed Bt rice genotype. The role of shoot herbivory in allelopathic induction is further supported when Bt plants also exhibited higher allelopathic potential after insect regurgitant application to the damaged leaves. Allelopathic potential was assessed through several methods after treatments of mechanical damage, insect feeding and insect regurgitant application to damaged rice leaves. Rhizosphere soil and leaf leachates of non-Bt rice cultivar exhibited higher allelopathic potential on lettuce and barnyard grass after herbivore feeding. Enzyme activities (PAL and C4H) responsible for biosynthesis of phenolic compounds and their concentration were significantly higher in non-Bt plant after herbivore feeding and attain the same level in Bt plants after insect regurgitant application to damaged leaves. Similarly, genes (OsPAL and OsCYC1) responsible for biosynthesis of allelopathic compounds showed high expression in non-Bt plants after herbivore feeding. Our results indicate that herbivore feeding enhance rice allelopathic potential and no insect feeding as incase of Bt plants may reduce allelopathic potential of genetically modified rice. 相似文献
999.
Mohamed Lotfy Jaipaul Singh Hameed Rashed Saeed Tariq Erika Zilahi Ernest Adeghate 《Cell and tissue research》2014,358(2):343-358
Incretins, such as glucagon-like peptide-1 (GLP)-1, have been shown to elevate plasma insulin concentration. The purpose of this study is to investigate the cellular and molecular basis of the beneficial effects of GLP-1. Normal and diabetic male Wistar rats were treated with GLP-1 (50 ng/kg body weight) for 10 weeks. At the end of the experiment, pancreatic tissues were taken for immunohistochemistry, immunoelectron microscopy and real-time polymerase chain reaction studies. Samples of blood were retrieved from the animals for the measurement of enzymes and insulin. The results show that treatment of diabetic rats with GLP-1 caused significant (P?0.05) reduction in body weight gain and blood glucose level. GLP-1 (10?12–10?6 M) induced significant (P?0.01) dose-dependent increases in insulin release from the pancreas of normal and diabetic rats compared to basal. Diabetes-induced abnormal liver (aspartate aminotransferase and alanine aminotransferase) and kidney (blood urea nitrogen and uric acid) parameters were corrected in GLP-1-treated rats compared to controls. GLP-1 treatment induced significant (P?0.05) elevation in the expression of pancreatic duodenal homeobox-1, heat shock protein-70, glutathione peroxidase, insulin receptor and GLP-1-receptor genes in diabetic animals compared to controls. GLP-1 is present in pancreatic beta cells and significantly (P?0.05) increased the number of insulin-, glutathione reductase- and catalase-immunoreactive islet cells. The results of this study show that GLP-1 is co-localized with insulin and seems to exert its beneficial effects by increasing cellular concentrations of endogenous antioxidant genes and other genes involved in the maintenance of pancreatic beta cell structure and function. 相似文献
1000.
Asif Mir Kumudesh Sritharan Kirti Mittal Nasim Vasli Carolina Araujo Talal Jamil Muhammad Arshad Rafiq Zubair Anwar Anna Mikhailov Sobiah Rauf Huda Mahmood Abdul Shakoor Sabir Ali Joyce So Farooq Naeem Muhammad Ayub John B. Vincent 《Human genetics》2014,133(8):975-984
In this study, we have performed autozygosity mapping on a large consanguineous Pakistani family segregating with intellectual disability. We identified two large regions of homozygosity-by-descent (HBD) on 16q12.2–q21 and 16q24.1–q24.3. Whole exome sequencing (WES) was performed on an affected individual from the family, but initially, no obvious mutation was detected. However, three genes within the HBD regions that were not fully captured during the WES were Sanger sequenced and we identified a five base pair deletion (actually six base pairs deleted plus one base pair inserted) in exon 7 of the gene FBXO31. The variant segregated completely in the family, in recessive fashion giving a LOD score of 3.95. This variant leads to a frameshift and a premature stop codon and truncation of the FBXO31 protein, p.(Cys283Asnfs*81). Quantification of mRNA and protein expression suggests that nonsense-mediated mRNA decay also contributes to the loss of FBXO31 protein in affected individuals. FBXO31 functions as a centrosomal E3 ubiquitin ligase, in association with SKP1 and Cullin-1, involved in ubiquitination of proteins targeted for degradation. The FBXO31/SKP1/Cullin1 complex is important for neuronal morphogenesis and axonal identity. FBXO31 also plays a role in dendrite growth and neuronal migration in developing cerebellar cortex. Our finding adds further evidence of the involvement of disruption of the protein ubiquitination pathway in intellectual disability. 相似文献