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981.
Synthesis and characterization of hapten-protein conjugates for antibody production against small molecules 总被引:15,自引:0,他引:15
For the generation of antibodies against small hapten molecules, the hapten is cross-linked with some carrier protein to make it immunogenic. However, the formation of such conjugates is not always reproducible. This may lead to inconsistent hapten-protein stoichiometries, resulting in large variations in the generation of the desired antibodies. In the study described here the hapten (mercaptopropionic acid derivative of atrazine) was coupled to carrier protein at five different molar ratios. The hapten-protein conjugates prepared were characterized thoroughly by spectrophotometric absorption, fluorescence, matrix-assisted laser desorption ionization (MALDI), and gel electrophoresis methods, before being used for the immunization and assay purposes. Electrophoresis and fluorescence methods were very useful in detecting hapten-protein cross-linking while MALDI-MS and spectrophotometric detection provided qualitatively comparable hapten density. The production of specific antibodies was sought following the generation of appropriate hapten-protein conjugates. A high antibody titer with moderate antibody specificity was obtained with hapten density around 15 molecules per carrier protein. The study proved useful for monitoring the course of hapten-protein conjugation for the production of specific antibodies against small molecules. 相似文献
982.
983.
984.
According to the GLOBOCAN statistics, cervical cancer is one of the leading causes of death among women worldwide. It is found to be gradually increasing in the younger population, specifically in the developing countries. We analyzed the protein-protein interaction networks of the uterine cervix cells for the normal and disease states. It was found that the disease network was less random than the normal one, providing an insight into the change in complexity of the underlying network in disease state. The study also portrayed that, the disease state has faster signal processing as the diameter of the underlying network was very close to its corresponding random control. This may be a reason for the normal cells to change into malignant state. Further, the analysis revealed VEGFA and IL-6 proteins as the distinctly high degree nodes in the disease network, which are known to manifest a major contribution in promoting cervical cancer. Our analysis, being time proficient and cost effective, provides a direction for developing novel drugs, therapeutic targets and biomarkers by identifying specific interaction patterns, that have structural importance. 相似文献
985.
Shail Singh B. B. Singh R. Chandra D. K. Patel V. Rai 《World journal of microbiology & biotechnology》2009,25(10):1821-1828
The consortium of Bacillus cereus (DQ002384), Serratia marcescens (AY927692) and Serratia marcescens (DQ002385) were used for pentachlorophenol (PCP) degradation. The consortia showed better overall removal efficiencies than
single strains by utilization of PCP as a carbon and energy source confirmed by pH dependent dye indicator bromocresol purple
(BCP) in mineral salt media (MSM). Mixed culture was found to degrade up to 93% of PCP (300 mg/l) as compared to single strains
(62.75–90.33%), at optimized conditions (30 ± 1°C, pH 7 ± 0.2, 120 rpm) at 168 h incubation. PCP degradation was also recorded
at 20°C (62.75%) and 37°C (83.33%); pH 6 (70%) and pH 9 (75.16%); 50 rpm (73.33%) and 200 rpm (91.63%). The simultaneous release
of chloride ion up to 90.8 mg/l emphasized the bacterial dechlorination in the medium. GC–MS analysis revealed the formation
of low molecular weight compound, i.e., 6-chlorohydroxyquinol, 2,3,4,6-tetrachlorophenol and tetrachlorohydroquinone, from
degraded sample as compared to control. 相似文献
986.
The present study demonstrates the regeneration of plantlets of guava (Psidium guajava L.) from somatic embryos developed under salt-stress conditions. With increasing concentrations of NaCl in induction medium
(MS + 4.52 μM 2,4-d + 5% sucrose) from 0 to 200 mM, the number of somatic embryos per responsive explant decreased. Somatic embryos induced on
0–100 mM NaCl containing medium developed into torpedo stages, whereas, the development of somatic embryos that differentiated
on 150 and 200 mM NaCl-supplemented medium was arrested prior to torpedo stage and did not undergo maturation phase. Somatic
embryos that developed on NaCl-containing medium, showed better germination in the presence of NaCl as compared with those
developed on medium without NaCl. The effect of increasing salt-stress was also investigated on plant growth, chlorophyll
and carotenoids, Na+ and K+, and proline and glycine betaine accumulation in in vitro grown plantlets. The level of Na+ in leaves increased with increasing concentrations of NaCl in the medium. Accumulation of free proline and glycine betaine
in leaves significantly increased with increasing salinity. The results suggest that accumulation of proline and glycine betaine
may be important for osmotic adjustment in guava under salinity stress. 相似文献
987.
988.
Ras genes are pre-eminent genes that are frequently linked with cancer biology. The functional loss of ras protein caused by various point mutations within the gene, is established as a prognostic factor for the genesis of a constitutively active Ras-MAPK pathway leading to cancer. Ras signaling circuit follows a complex pathway, which connects many signaling molecules and cells. Several strategies have come up for targeting mutant ras proteins for cancer therapy, however, the clinical benefits remain insignificant. Targeting the Ras-MAPK pathway is extremely complicated due its intricate networks involving several upstream and downstream regulators. Blocking oncogenic Ras is still in latent stage and requires alternative approaches to screen the genes involved in Ras transformation. Understanding the mechanism of Ras induced tumorigenesis in diverse cancers and signaling networks will open a path for drug development and other therapeutic approaches. 相似文献
989.
A stable dispersion of multifunctional Gd2O3:Er,Yb phosphor in polyvinyl alcohol (PVA) was synthesized by varying the concentration of Yb3+ ions. It had a strong ultraviolet–visible‐near infrared (UV–vis) upconversion emission and applications in temperature and magnetic field sensors (e.g., nano‐heaters), as well as potential use in bioleveling and bioimaging. Stability of the dispersion was found to strongly depend on the mixing process of the powder in the polymer solution. Spherical shaped nanoparticles in cubic phase of ~ 43 nm diameter were synthesized and characterized by X‐ray diffraction; results were confirmed by scanning electron microscopy (SEM). Fourier transform infrared sspectroscopy (FT‐IR) and thermal analysis supported the presence of PVA. NIR pumping produced strong UC emission bands in the red and green regions extending up to very high UV (240 nm). This method provides an alternative for synthesizing a highly UC‐efficient non‐agglomerated pure transparent dispersion from various efficient phosphors for biological applications. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
990.
H. A. Simmonds J. S. Cameron D. J. Goldsmith L. D. Fairbanks G. Venkat Raman 《Nucleosides, nucleotides & nucleic acids》2013,32(9-11):1071-1075
Renal disease is rare today in classic adult gout, and gout is rare in renal disease—especially in the young. Here we summarise studies in 158 patients from 31 kindreds diagnosed with familial juvenile hyperuricaemic nephropathy FJHN from a total of 230 kindred members studied in Great Britain. Some patients have been followed for up to 30 years, and allopurinol has ameliorated the progression of the renal disease in all 113 surviving members provided: 1. They have been diagnosed and treated sufficiently early. 2. Compliance with allopurinol treatment and diet has been as important as early recognition. 3. Hypertension has been rigorously controlled. 4. The use of oral contraceptives has been avoided, as has pregnancy in any female with a Glomelar Filtration Rate GFR <70 ml/min. The question arising is: Why is FJHN the most prevalent genetic purine disorder diagnosed in Britain? Is it a lack of awareness which needs to be improved Europe-wide? 相似文献