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71.
c-myb plays an important role in the regulation of cell growth and differentiation, and is highly expressed in immature hematopoietic cells. The human chronic myelogenous leukemia cell K562, highly expresses IGF-I, IGF-II, IGF-IR, and IGF-induced cellular proliferation is mediated by IGF-IR. To characterize the impact of c-myb on the IGF-IGFBP-3 axis in leukemia cells, we overexpressed c-myb using an adenovirus gene transfer system in K562 cells. The overexpression of c-myb induced cell proliferation, compared to control, and c-myb induced cell growth was inhibited by anti-IGF-IR antibodies. c-myb overexpression resulted in a significant increase in the expression of IGF-I, IGF-II, and IGF-IR, and a decrease in IGFBP-3 expression. By contrast, disruption of c-myb function by DN-myb overexpression resulted in significant reduction of IGF-I, IGF-II, IGF-IR, and elevation of IGFBP-3 expression. In addition, exogenous IGFBP-3 inhibited the proliferation of K562 cells, and c-myb induced cell growth was blocked by IGFBP-3 overexpression in a dose-dependent manner. The growth-promoting effects of c-myb were mediated through two major intracellular signaling pathways, Akt and Erk. Activation of Akt and Erk by c-myb was completely blocked by IGF-IR and IGFBP-3 antibodies. These findings suggest that c-myb stimulates cell growth, in part, by regulating expression of the components of IGF-IGFBP axis in K562 cells. In addition, disruption of c-myb function by DN-myb may provide a useful strategy for treatment of leukemia.  相似文献   
72.
We have recently developed a computational technique that uses mutually orthogonal Latin square sampling to explore the conformational space of oligopeptides in an exhaustive manner. In this article, we report its use to analyze the conformational spaces of 120 protein loop sequences in proteins, culled from the PDB, having the length ranging from 5 to 10 residues. The force field used did not have any information regarding the sequences or structures that flanked the loop. The results of the analyses show that the native structure of the loop, as found in the PDB falls at one of the low energy points in the conformational landscape of the sequences. Thus, a large portion of the structural determinants of the loop may be considered intrinsic to the sequence, regardless of either adjacent sequences or structures, or the interactions that the atoms of the loop make with other residues in the protein or in neighboring proteins.  相似文献   
73.
This article presents the pre‐clinical evaluation of our custom‐built, single‐band microwave radiometer centered at 1.3 GHz for deep tissue thermometry, and a pilot study on volunteers for passive detection of inflammation in knee joints. The electromagnetic (EM) compatibility of the battery‐operated radiometer for clinical use was assessed as per International Special Committee on Radio Interference (CISPR) 22 standard. The ability to detect inflammation in knee joints was assessed using a substrate integrated waveguide antenna connected to the radiometer. EM compatibility tests carried out in the laboratory indicated device immunity to intentional radiated interference up to ?20 dBm injected power in the global system for mobile communication frequency band, and pre‐compliance to CISPR 22 standard. Radiometer temperature measurements recorded at the lateral and medial aspects of both knees of 41 volunteers indicated mean temperature greater than 33°C for the diseased sites compared with the mean temperature of 28°C measured for the healthy sites. One‐way analysis of variance statistics indicated significantly (P < 0.005) higher radiometer temperature at the diseased sites unlike the healthy sites. Thus, the EM pre‐compliance of the device and the potential to measure deep tissue inflammation were demonstrated. Bioelectromagnetics. 2019;40:402–411. © 2019 Bioelectromagnetics Society.  相似文献   
74.
Inland waters were recently recognized to be important sources of methane (CH4) and carbon dioxide (CO2) to the atmosphere, and including inland water emissions in large scale greenhouse gas (GHG) budgets may potentially offset the estimated carbon sink in many areas. However, the lack of GHG flux measurements and well‐defined inland water areas for extrapolation, make the magnitude of the potential offset unclear. This study presents coordinated flux measurements of CH4 and CO2 in multiple lakes, ponds, rivers, open wells, reservoirs, springs, and canals in India. All these inland water types, representative of common aquatic ecosystems in India, emitted substantial amounts of CH4 and a major fraction also emitted CO2. The total CH4 flux (including ebullition and diffusion) from all the 45 systems ranged from 0.01 to 52.1 mmol m?2 d?1, with a mean of 7.8 ± 12.7 (mean ± 1 SD) mmol m?2 d?1. The mean surface water CH4 concentration was 3.8 ± 14.5 μm (range 0.03–92.1 μm ). The CO2 fluxes ranged from ?28.2 to 262.4 mmol m?2 d?1 and the mean flux was 51.9 ± 71.1 mmol m?2 d?1. The mean partial pressure of CO2 was 2927 ± 3269 μatm (range: 400–11 467 μatm). Conservative extrapolation to whole India, considering the specific area of the different water types studied, yielded average emissions of 2.1 Tg CH4 yr?1 and 22.0 Tg CO2 yr?1 from India's inland waters. When expressed as CO2 equivalents, this amounts to 75 Tg CO2 equivalents yr?1 (53–98 Tg CO2 equivalents yr?1; ± 1 SD), with CH4 contributing 71%. Hence, average inland water GHG emissions, which were not previously considered, correspond to 42% (30–55%) of the estimated land carbon sink of India. Thereby this study illustrates the importance of considering inland water GHG exchange in large scale assessments.  相似文献   
75.
Acinetobacter calcoaceticus utilizes catechin as sole carbon source. The chromosomal region involved in catechin catabolism was cloned in Escherichia coli DH5alpha from the genomic DNA of A. calcoaceticus. A recombinant E. coli containing 9.2 kb DNA fragment of A. calcoaceticus inserted in pUC19 showed a halo zone around the colony in plate assays, indicating the catechin utilizing ability of the clone. Enzyme assays revealed the expression of the cloned DNA fragment of A. calcoaceticus. High performance thin layer chromatography confirmed protocatechuic acid and phloroglucinol carboxylic acid as cleavage products of catechin in A. calcoaceticus and the catechin degrading ability of the clones. A. calcoaceticus followed the beta-ketoadipate pathway for catechin degradation. The sub-clone (pASCI) of this insert was sequenced and analyzed. The sequence showed three major ORFs but only ORF 2 showed similarities to other aromatic oxygenases and the sequence of ORF 2 was submitted to GenBank (AF369935).  相似文献   
76.
The polysaccharide-fucoidan was extracted from brown seaweed Sargassum wightii and characterized through FT-IR and 13C & 1H NMR analysis. The extracted fucoidan was supplemented with pellet diets at three different concentrations (0.1, 0.2 and 0.3%). The fucoidan supplemented diets were fed to Penaeus monodon for 45 days, then challenged with WSSV and the mortality percentage was recorded daily up to 21 days. During the challenge test, the control group showed 100% mortality within 10 days, but in the experimental groups, the mortality percentage (51-72% within 21 days) was decreased considerably (P < 0.05) with respect to the concentrations of fucoidan. The reduction in mortality percentage of experimental groups over control group was ranged from 50.81 to 68.06%. During challenge experiment, the immunological parameters such as THC, prophenoloxidase activity, respiratory burst activity, superoxide dismutase activity and phagocytic activity were measured before injection of WSSV (0 day) and after the injection of WSSV on 10th and 21st days, respectively. All the immunological parameters of experimental groups were significantly (P < 0.05) increased than control group. RT-PCR analysis confirmed the considerable reduction of WSSV DNA copy numbers with respect to the concentration of fucoidan. It was concluded that P. monodon fed with fucoidan of S. wightii supplemented diet had enhanced the innate immunity and increased resistance against WSSV infection.  相似文献   
77.
Protein function is often modulated by protein-protein interactions (PPIs) and therefore defining the partners of a protein helps to understand its activity. PPIs can be detected through different experimental approaches and are collected in several expert curated databases. These databases are used by researchers interested in examining detailed information on particular proteins. In many analyses the reliability of the characterization of the interactions becomes important and it might be necessary to select sets of PPIs of different confidence levels. To this goal, we generated HIPPIE (Human Integrated Protein-Protein Interaction rEference), a human PPI dataset with a normalized scoring scheme that integrates multiple experimental PPI datasets. HIPPIE's scoring scheme has been optimized by human experts and a computer algorithm to reflect the amount and quality of evidence for a given PPI and we show that these scores correlate to the quality of the experimental characterization. The HIPPIE web tool (available at http://cbdm.mdc-berlin.de/tools/hippie) allows researchers to do network analyses focused on likely true PPI sets by generating subnetworks around proteins of interest at a specified confidence level.  相似文献   
78.

Background  

Information regarding the Alkali-Tolerance Response (AlTR) in Listeria monocytogenes is very limited. Treatment of alkali-adapted cells with the protein synthesis inhibitor chloramphenicol has revealed that the AlTR is at least partially protein-dependent. In order to gain a more comprehensive perspective on the physiology and regulation of the AlTR, we compared differential gene expression and protein content of cells adapted at pH 9.5 and un-adapted cells (pH 7.0) using complementary DNA (cDNA) microarray and two-dimensional (2D) gel electrophoresis, (combined with mass spectrometry) respectively.  相似文献   
79.
80.
The water soluble polymer-copper(II) complex samples, [Cu(bpy)(2)(BPEI)]Cl(2).4H(2)O (bpy=2,2'-bipyridine, BPEI=branched polyethyleneimine), with varying degrees of copper(II) chelates content in the polymer chain, were prepared by ligand substitution method in water-ethanol medium and characterized by Infra-red, UV-visible, EPR spectral and elemental analysis methods. The interaction of these polymer-copper(II)-bipyridyl complex samples with calf thymus DNA has been explored by using electronic absorption spectroscopy, emission spectroscopy and gel electrophoresis techniques. The observed changes in the physico-chemical features of the polymer-copper(II) complex on binding to DNA suggest that the complex binds to DNA with electrostatic interaction mode. A sample of polymer-copper(II) complex was tested for its antibacterial and antifungal activity and it was found to have good antibacterial and antifungal activities.  相似文献   
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