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21.
Kealley CS Rout MK Dezfouli MR Strounina E Whittaker AK Appelqvist IA Lillford PJ Gilbert EP Gidley MJ 《Biomacromolecules》2008,9(10):2937-2946
We report a multitechnique study of structural organization and molecular mobility for soy glycinin at a low moisture content (<30% w/w) and relate these to its glass-to-rubber transition. Small-angle X-ray scattering (SAXS), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy are used to probe structure and mobility on different length and time scales. NMR (approximately 10(-6) to 10(-3) s) reveals transitions at a higher moisture content (>17%) than DSC or SAXS, which sample for much longer times (approximately 10 to 10(3) s) and where changes are detected at >13% water content at 20 degrees C. The mobility transitions are accompanied by small changes in unit-cell parameters and IR band intensities and are associated with the enhanced motion of the polypeptide backbone. This study shows how characteristic features of the ordered regions of the protein (probed by SAXS and FTIR) and mobile segments (probed by NMR and DSC) can be separately monitored and integrated within a mobility transformation framework. 相似文献
22.
In‐line monitoring of amino acids in mammalian cell cultures using raman spectroscopy and multivariate chemometrics models
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Hemlata Bhatia Hamidreza Mehdizadeh Denis Drapeau Seongkyu Yoon 《Engineering in Life Science》2018,18(1):55-61
The application of PAT for in‐line monitoring of biopharmaceutical manufacturing operations has a central role in developing more robust and consistent processes. Various spectroscopic techniques have been applied for collecting real‐time data from cell culture processes. Among these, Raman spectroscopy has been shown to have advantages over other spectroscopic techniques, especially in aqueous culture solutions. Measurements of several process parameters such as glucose, lactate, glutamine, glutamate, ammonium, osmolality and VCD using Raman‐based chemometrics models have been reported in literature. The application of Raman spectroscopy, coupled with calibration models for amino acid measurement in cell cultures, has been assessed. The developed models cover four amino acids important for cell growth and production: tyrosine, tryptophan, phenylalanine and methionine. The chemometrics models based on Raman spectroscopy data demonstrate the significant potential for the quantification of tyrosine, tryptophan and phenylalanine. The model for methionine would have to be further refined to improve quantification. 相似文献
23.
Extracellular signal-regulated kinase 1 and 2 in cancer therapy: a focus on hepatocellular carcinoma
Amir Mehdizadeh Mohammad Hossein Somi Masoud Darabi Mortaza Jabbarpour-Bonyadi 《Molecular biology reports》2016,43(2):107-116
Extracellular signal-regulated kinases (ERK) pathway plays a crucial role in cancer cell survival and proliferation. This signaling pathway has been related to epithelial to mesenchymal transition and drug resistance in hepatocellular carcinoma (HCC) cells, which is a common challenge in chemotherapy. Consequently, mediators of this pathway have recently been considered as novel therapeutic targets in HCC. In this review the impact of ERK1 and ERK2 as major components of ERK signaling pathway, in HCC biology and drug resistance will be highlighted and discussed. 相似文献
24.
Maryam Pakfetrat Leila Malekmakan Mahshid Hasheminasab 《Biological trace element research》2010,137(3):335-339
In this cross-sectional study, selenium (Se) levels in the sera of 35 hemodialysis (HD) patients and 34 patients undergoing
continuous ambulatory peritoneal dialysis (CAPD) for more than 3 months were compared with the serum Se levels of 34 healthy
volunteers. The observed Se levels of 100.8 ± 51.9 μg/L in the sera of the HD patients and of 65.5 ± 32.1 μg/L in the sera
of the CAPD patients were significantly lower than the 134.9 ± 81.2 μg/L of the controls, with p = 0.002 and 0.02, respectively. Furthermore, the Se levels were significantly higher in the HD rather than the CAPD patients
(p = 0.01). In the spent dialysate effluent fluid of 32 of the CAPD patients Se was undetectable, in the remaining two CAPD
patients the Se levels were 1.9 and 4.6μg/l, respectively. The low Se levels of HD and CAPD patients as compared to healthy
persons are attributed to diminished Se retention due to chronic oxidative stress. 相似文献
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Leila Mehdizadeh Parisa Taheri Abdullah Ghasemi Pirbalouti Mohammad Moghaddam 《Physiology and Molecular Biology of Plants》2020,26(4):759-771
This study was performed to investigate the constituents, in vitro antifungal activity and phytotoxicity potential of the essential oil from Juniperus polycarpos var. turcomanica leaves. The essential oil was analyzed by GC–FID, and GC/MS, which predominantly contains α-pinene (51.21%), germacrene–B (4.80%), and ∆-cadinene (2.56%). The antifungal activity of the essential oil against some phytopathogenic fungi, including Alternaria alternata, Colletotrichum trichellum, Curvularia fallax, Cytospora sacchari, Fusarium oxysporum, and Macrophomina phaseolina was performed through disk diffusion and agar dilution assays. The essential oil of J. polycarpos var. turcomanica had high antifungal activity against tested phytopathogenic fungi. The most susceptible fungi to the essential oil were C. trichellum in agar dilution and M. phaseolina and C. fallax in disk diffusion methods, whereas, the most resistant fungus to the essential oil was obtained from A. alternata in both assays. Screening methods had an influence on antifungal activity of the essential oil as most of the tested fungi in this study were shown to be more resistant in disc diffusion methods. According to the phytotoxic assay results, the essential oil from J. polycarpos var. turcomanica had high phytotoxicity against three species of weeds, including P. oleracea L., A. retroflexus L., and D. stramonium L. The results of this research suggest that the herbicidal and antifungal activities of the essential oil from J. polycarpos var. turcomanica can be attributed to its major group of constituents, monoterpenes hydrocarbons. 相似文献
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Elham Gholipour Houman Kahroba Nasim Soltani Parisa Samadi Parisa Sarvarian Sajjad VakiliSamiani Abbas Ali Hosein Pour Feizi Mohammad
Sadegh SoltaniZangbar Adel Baghersalimi Bahram Darbandi Aliakbar Movassaghpour Mehdi Talebi Roza Motavalli Amir Mehdizadeh Abdolhassan Kazemi Mehdi Yousefi 《Journal of cellular and molecular medicine》2022,26(16):4566
29.
Interferons, IFNs, are among the most widely studied and clinically used biopharmaceuticals. Despite their invaluable therapeutic roles, the widespread use of IFNs suffers from some inherent limitations, mainly their relatively short circulation lifespan and their unwanted effects on some non-target tissues. Therefore, both these constraints have become the central focus points for the research efforts on the development of a variety of novel delivery systems for these therapeutic agents with the ultimate goal of improving their therapeutic end-points. Generally, the delivery systems currently under investigation for IFNs can be classified as particulate delivery systems, including micro- and nano-particles, liposomes, minipellets, cellular carriers, and non-particulate delivery systems, including PEGylated IFNs, other chemically conjugated IFNs, immunoconjugated IFNs, and genetically conjugated IFNs. All these strategies and techniques have their own possibilities and limitations, which should be taken into account when considering their clinical application. In this article, currently studied delivery systems/techniques for IFN delivery have been reviewed extensively, with the main focus on the pharmacokinetic consequences of each procedure. 相似文献
30.
Maryam Zahedifar Ali Akbar Moosavi Zahra Zarei Mahshid Shafigh Fereshteh Karimian 《International journal of phytoremediation》2019,21(5):435-447
AbstractDespite the fact that cadmium (Cd) is a non-essential element for plants, it can influence nutrients and affect human health. Potassium (K) can influence the transportation of heavy metals (HMs) in soil-plant systems. Here, a greenhouse experiment was conducted to evaluate the effect of Cd and K fertilizers on the different partitioning forms of HMs, their concentrations, uptake in the shoots and roots of Ocimum basilicum. Treatments comprised 2 levels of Cd (0 and 40?mg kg?1) and three levels of K (0, 100, and 200?mg kg?1) from three sources, i.e. KCl, K2SO4, and K-nano-chelate. 40?mg Cd kg?1 increased the shoot (above ground parts) Cd concentration. Addition of K as KCl, K2SO4, and K-nano-chelate increased the presence of Cd in shoots by 86, 82 and 76%, respectively, compared to the control. Using the nano-chelate of K can increase the accumulation of Cd in plants grown on contaminated soils to lesser content than that of the other forms of K. Application of 40?mg Cd kg?1 reduced the concentration of Zn, Cu, and Mn in the shoot, but increased shoot Fe concentration. Transfer factor (TF), which is the ratio of metal concentration in shoot to its concentration in root, of the studied HMs, was significantly affected by Cd and K treatments. Therefore, the proper form and dose of chemical fertilizers should be applied in Cd-contaminated soils. 相似文献