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91.
Chromium(III) is often claimed to have a positive effect on body composition, while the responses in researches with supplementation
of different chemical form of chromium are various and inconsistent. We have studied the effects of 6 weeks of treatment with
three different forms of chromium (300 μg/kg) as chromium chloride, chromium tripicolinate, and chromium nanocomposite (CrNano)
on growth, body composition, serum parameters, and tissue chromium in rats. The supplementataion of CrNano significantly increased
average daily gain, food efficiency, and lean body mass and decreased fat mass and body fat proportion and serum levels of
glucose, urea nitrogen, triglyceride, and insulin. Chromium contents in liver, kidney, and hind leg muscle were increased
significantly with the addition of CrNano in diet. The results indicate that chromium nanocomposite has higher efficacy on
growth and body composition compared to the traditional chromium agents. 相似文献
92.
Tokumura A Kume T Fukuzawa K Tahara M Tasaka K Aoki J Arai H Yasuda K Kanzaki H 《Life sciences》2007,80(18):1641-1649
Levels of lysophosphatidic acid (LPA), an important phospholipid mediator, in serum and ascitic fluid from ovarian cancer patients were shown to be higher than those from healthy women and from patients with other type of cancer, respectively. Although LPA in human serum seems mainly to be generated by lysophospholipase D (lysoPLD), the source and pathway for LPA in the ascitic fluid remain still obscure. In this study, we examined whether lysoPLD activity producing bioactive LPA in human peritoneal fluid was significantly elevated under pathological statuses. Lysophospholipase D activity in human peritoneal fluids was measured by quantifying choline released from exogenous lysophosphatidylcholine on their incubation at 37 degrees C. We also compared the activity of lysoPLD in sera from patients with different gynecologic diseases. We found relatively high lysoPLD activity in peritoneal fluids from patients with ovarian cancer, dermoid cyst or mucinous cystadenoma, whereas there were no significant differences in the serum lysoPLD activity among clinical groups and healthy subjects. The lysoPLD in the peritoneal fluid was found to have similar substrate specificity and metal ion requirement to those of serum lysoPLD, that has been identified as autotaxin, a tumor cell-motility stimulating protein. Our results suggest that increased lysoPLD activity in peritoneal fluid from patients with certain gynecologic tumors might be relevant to its potential of tumor progression. 相似文献
93.
This article describes a multicommutated flow injection-solid phase spectroscopy system implemented with photochemically induced fluorescence for the determination of flufenamic acid (FFA). A strongly fluorescent photoproduct is generated when FFA is irradiated online under UV light in a strong sulfuric medium. The photoproduct generated is retained on C(18) silica gel (which fills the detection area of the flow cell) and directly monitored on the active solid support at 258/442 nm (lambda(ex)/lambda(em)). After maximum signal recording, the sensing zone is regenerated by eluting the retained photoproduct with an appropriate H(2)SO(4)/MeOH solution. The sensor, completely automated, is based on the use of three-way solenoid valves conveniently operated by a homemade multicommutation software written in Java language. The system is calibrated at 10 and 60s for sampling time, showing detection limits of 1.28 x 10(-9) and 5.33 x 10(-10) molL(-1) and sampling rates of 38 and 28 h(-1), respectively, with relative standard deviations of 0.9 and 1.2%. The applicability of the method is demonstrated for the determination of FFA in human serum, human urine, and a pharmaceutical preparation without any pre-treatment. Good recovery levels were achieved between 90.5 and 103.7%. 相似文献
94.
95.
With the development of cell-based assays and therapies, the purity of reagents used to grow and maintain cells has become
much more important. In particular, the use of fetal calf serum for culturing cells presents a direct path for potential contamination
of cell cultures. In recent years, much research has focused on the development of serum-free culturing systems, not only
to alleviate difficulties due to availability and cost of fetal calf serum but also to prevent the transmission of potentially
fatal diseases to human patients. Additionally, methods need to be developed for long-term storage of cell stocks that also
reduce the risk of exposure to harmful diseases. As most methods employ fetal calf serum in their freezing formulations, solutions
that avoid the use of fetal calf serum while providing equivalent or better recovery of cells upon thawing would be ideal.
In this study, two vascular cell lines have been cryopreserved as adherent cell populations in two widely used cryoprotectants,
dimethyl sulfoxide and 1,2-propanediol, and two vehicle solutions, Euro-Collins and Unisol-cryoprotectant vehicle specifically
formulated for the maintenance of cell homeostasis at temperatures below 37° C. The addition of serum to these formulations
was also evaluated to determine if its presence provided any additional benefit to the cells during cryopreservation. The
results demonstrated that using vehicle solutions designed for lower temperatures produced viable cells that retained cell
population viability values up to 75% of unfrozen controls. These results also demonstrated that including serum in the formulation
provided no additional benefit to the cells and in some cases actually produced lower cell viability after cryopreservation.
In conclusion, the development of solutions designed for low-temperature storage of cells provides a viable alternative to
more conventional cryopreservation protocols and eliminates the necessity of including serum in these formulations. 相似文献
96.
Yamaguchi H Zhu J Yu T Sasaki K Umetsu H Kidachi Y Ryoyama K 《Cell biology international》2007,31(6):638-644
97.
《European journal of cell biology》2022,101(4):151280
Early discover of risk progression of invisible carcinomas is important for a prerequisite successful treatment. Here, we investigated whether concentration of human thymidine kinase 1 (HTK1) discover invisible malignant human tumours. The HTK1 concentration of tumour cellular based on HTK1 IgY-polyclonal-antibody (HTK1-IgY-pAb) was determined by using a novel automatic chemiluminescence analyser with sandwich biotin-streptavidin (SBSA) platform. Minimum number of cells able to be detected by this technology used cells with low and high concentration of HTK1. The limit visibility by tumour imaging is approximately 1 mm in diameter, corresponding to approximately 109 cells with a cell diameter of 1 µm. Based on a HTK1 standard curve and a molecular weight of HTK1 of 96 kD, the HTK1protein (HTK1p) concentration per cell was calculated to be 0.021 pg. Assuming 200 pg in total protein/cell, approximately 50 × 106 growing malignant cells in the body were calculated to releases HTK1 into 5-liter blood. A HTK1 values of 3.914, 0.435 and 0.009 pmol/L corresponds to 10 × 105, 2 × 105 and 1 × 105 growing malignant cells, respectively. The lowest detectable sensitivity of HTK1 is 0.009 pmol/L in 1 × 105 growing malignant cells and 0.01 pmol/L in blood serum, detectable in health screening. Comparing the novel automatic chemiluminescence analyser with the original ECL dot-blot assay using serum HTK1p (health screening, n = 265) showed high correlation (r = 0.8743, P < .000). In conclusion, the novel automatic chemiluminescence analyser with SBSA platform is a reliable method with high accuracy to determine carcinoma invisible. 相似文献
98.
Maria E. Hassis Richard K. Niles Miles N. Braten Matthew E. Albertolle H. Ewa Witkowska Carl A. Hubel Susan J. Fisher Katherine E. Williams 《Analytical biochemistry》2015
High quality clinical biospecimens are vital for biomarker discovery, verification, and validation. Variations in blood processing and handling can affect protein abundances and assay reliability. Using an untargeted LC-MS approach, we systematically measured the impact of preanalytical variables on the plasma proteome. Time prior to processing was the only variable that affected the plasma protein levels. LC-MS quantification showed that preprocessing times <6 h had minimal effects on the immunodepleted plasma proteome, but by 4 days significant changes were apparent. Elevated levels of many proteins were observed, suggesting that in addition to proteolytic degradation during the preanalytical phase, changes in protein structure are also important considerations for protocols using antibody depletion. As to processing variables, a comparison of single- vs double-spun plasma showed minimal differences. After processing, the impact ?3 freeze–thaw cycles was negligible regardless of whether freshly collected samples were processed in short succession or the cycles occurred during 14–17 years of frozen storage (−80 °C). Thus, clinical workflows that necessitate modest delays in blood processing times or employ different centrifugation steps can yield valuable samples for biomarker discovery and verification studies. 相似文献
99.
Mechanism of Dimercaptosuccinic Acid Coated Superparamagnetic Iron Oxide Nanoparticles with Human Serum Albumin
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Lining Zhao Wei Song Jing Wang Yunxing Yan Jiangwei Chen Rutao Liu 《Journal of biochemical and molecular toxicology》2015,29(12):579-586
To research the mechanism of dimercaptosuccinic acid coated‐superparamagnetic iron oxide nanoparticles (SPION) with human serum albumin (HSA), the methods of spectroscopy, molecular modeling calculation, and calorimetry were used in this paper. The inner filter effect of the fluorescence intensity was corrected to obtain the accurate results. Ultraviolet–visible absorption and circular dichroism spectra reflect that SPION changed the secondary structure with a loss of α‐helix and loosened the protein skeleton of HSA; the activity of the protein was also affected by the increasing exposure of SPION. Fluorescence lifetime measurement indicates that the quenching mechanism type of this system was static quenching. The isothermal titration calorimetry measurement and molecular docking calculations prove that the predominant force of this system was the combination of Van der Waals’ force and hydrogen bonds. 相似文献
100.
Binding of Paeonol to Human Serum Albumin: A Hybrid Spectroscopic Approach and Conformational Study
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Juan Wang 《Journal of biochemical and molecular toxicology》2015,29(5):213-220
The purpose of this study was to elucidate the binding of paeonol to human serum albumin (HSA) through spectroscopic methods. The fluorescence quenching of HSA by paeonol was a result of the formation of the HSA–paeonol complex with low binding affinity (K = 4.45 × 103 M?1 at 298 K). Thermodynamic parameters (ΔG○ = –2.08 × 104 J·mol?1, ΔS○ = 77.9 J·mol?1·K?1, ΔH○ = 2.41 × 103 J·mol?1, kq = 9.67 × 1012 M?1·s?1) revealed that paeonol mainly binds HSA through hydrophobic force following a static quenching mode. The binding distance was estimated to be 1.91 nm by fluorescence resonant energy transfer. The conformation of HSA was changed and aggregates were formed in the presence of paeonol, revealed by synchronous fluorescence, circular dichroism, Fourier transform infrared spectroscopy, three‐dimensional fluorescence spectroscopy, and resonance light scattering results. 相似文献