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991.
High-performance affinity chromatography with immobilization of protein A and L-histidine on molded monolith 总被引:2,自引:0,他引:2
Reactive monoliths of macroporous poly(glycidyl methacrylate-co-ethylene dimethacrylate) have been prepared by "in-situ" copolymerization of the monomers in the presence of porogenic diluents. Protein A and L-histidine were immobilized on the monoliths directly or through a spacer arm, respectively. The properties of these two kinds of affinity columns were characterized, and the results showed that the columns with coupling of ligands by a spacer arm have some extent of non-specific adsorption for bovine serum albumin. The affinity column based on the monolithic polymer support provided us with good hydrodynamic characteristic, low flow resistance, and easy preparation. These two affinity columns were used for the purification of immunoglobulin G from human serum. The purity of the purified IgG was detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The stability of the protein A affinity column was investigated, and its performance remained invariable after half a year. The effects of the nature and the pH of the buffer system on the adsorption capacity of human IgG on histidyl affinity column were also investigated. The protein A affinity column is favorable for rapid analysis of human IgG samples. In contrast, the advantages of mild elution conditions, high stability, as well as low cost provide the histidyl column further potential possibility for fast removal of IgG from human plasma in clinical applications. 相似文献
992.
993.
Oligodeoxynucleotide complementary to c-fos mRNA was applied to characterize its effect on the spinal cord Fos expression and relevant nociceptive behaviors challenged by subcutaneous injection of bee venom to the rat hind paw. Nociceptive behavioral responses (spontaneous pain and hyperalgesia) following bee venom (0.2 mg/50 microl) injection were assessed in adult male Sprague-Dawley rats receiving intrathecal administration of c-fos antisense oligodeoxynucleotide (ASO, 50 microg/10 microl), sense oligodeoxynucleotide (SO, 50 microg/10 microl) and saline (10 microl) 4 h prior to bee venom injection. The lumbar spinal cord expression of Fos protein 2 h after bee venom injection in the ASO-, SO- and saline-treated animals was observed by immunohistochemistry. The results showed that pretreatment of c-fos ASO markedly reduced the flinching response and primary thermal hyperalgesia, but without significant effects on mechanical hyperalgesia and secondary thermal hyperalgesia. At the same time, ASO treatment also significantly decreased the expression of Fos protein within the lumbar region of the spinal cord ipsilateral to the injection. The results provide further evidence that Fos protein contributes to the activation of the spinal dorsal horn neurons and the generation and/or maintenance of spontaneous pain and primary thermal hyperalgesia induced by subcutaneous injection of bee venom. 相似文献
994.
Protein kinase C gamma isoform (PKCgamma) is present at high levels in the spinal and medullary dorsal horns and is thought to play a role in the sensitization of dorsal horn neurons in certain pain states. Calbindin-D28k (CB), calretinin (CR) and parvalbumin (PV) are the most commonly expressed calcium-binding proteins and are located abundantly in the medullary dorsal horn (also called the caudal subnucleus of the spinal trigeminal nucleus). In the present study, immunofluorescence histochemical double staining for PKCgamma and CB, CR or PV was performed in the rat medullary dorsal horn. Most of the PKCgamma-, CB-, CR- and PV-immunoreactive neurons were observed in lamina II; some were also encountered in lamina I and lamina III of the medullary dorsal horn. Neurons co-expressing CB/PKCgamma, CR/PKCgamma and PV/PKCgamma were also mainly found in lamina II, while in lamina I and lamina III, only a few neurons co-expressing CB/PKCgamma, CR/PKCgamma and PV/PKCgamma were encountered. The percentages of neurons co-expressing CB/PKCgamma in the total numbers of CB- and PKCgamma-immunoreactive neurons were 6.7 and 5.9%, respectively. Of the total numbers of CR- and PKCgamma-immunoreactive neurons, 5.0 and 5.6%, respectively, showed both CR and PKCgamma immunoreactivities. The percentages of neurons co-expressing PV/PKCgamma in the total numbers of PV- and PKCgamma-immunoreactive neurons were 25.7 and 4.1%, respectively. Most of these neurons co-expressing CB/PKCgamma, CR/PKCgamma and PV/PKCgamma were small (=15 microm) and medium-sized (16-35 microm) neurons and had round, triangular or fusiform-shaped cell bodies; large (>/=36 microm) multipolar neurons were infrequently seen. The present results indicate that there are some neurons co-expressing CB/PKCgamma, CR/PKCgamma and PV/PKCgamma in the medullary dorsal horn. These neurons might play important roles in the nociceptive modulation from the oro-facial region. 相似文献
995.
Gioconda San-Blas Françoise Sorais Gustavo Niño-Vega Cioly Méndez Felipe San-Blas 《Current microbiology》1998,37(2):141-143
Cytosolic proteinases were assayed in both morphological phases of Paracoccidioides brasiliensis. Preparations from the mycelial phase were more active in vitro than those from the yeast cells. Optimal proteinase activities
for both phases occurred at pH's between 6.0 and 9.0, and at 45°C. Gelatin-SDS-PAGE electrophoresis separated several bands
(58–112 kDa) in mycelial preparations; a single band (70 kDa) was seen in yeast preparations. Enzymatic activities were inhibited
by antipain, phenyl methyl sulfonyl fluoride (PMSF), and chymostatin, suggestive of serine proteinases. Partial inhibition
of the mycelial enzymes by ethylene diamine tetraacetic acid (EDTA), 1,10-phenanthroline, and iodoacetamide, also suggested
the presence of cysteine- and metallo-proteinases. The enzymatic activity increased in preparations extracted from yeast cells
transforming to mycelia, and decreased in preparations obtained from the reverse process.
Received: 29 September 1997 / Accepted: 19 February 1998 相似文献
996.
Michele Glinn Binhui Ni Robert P. Irwin S. W. Kelley Sui-Zhen Lin Steven M. Paul 《Journal of neurochemistry》1998,70(5):1850-1858
Abstract: Inorganic phosphate (Pi ) plays a vital role in intracellular energy metabolism. Its many effects include stimulation of glucose use, enhancement of high-energy phosphate concentrations, and modulation of cytosolic free [Ca2+ ]. Cultured fetal rat cortical neurons constitutively import Pi , and cytosolic levels positively correlate with [ATP], [NADPH], and energy charge. In the present study, we demonstrate that the concentration of intracellular Pi is an important determinant of acute neuronal survival after an excitotoxic or oxidative insult to cultured fetal rat cortical neurons. Extracellular Pi dose-dependently enhanced survival of cortical neurons after exposure to NMDA at early (≤6 h) time points after termination of the insult. Pi similarly increased neuronal survival after exposure to kainic acid or H2 O2 . Pi -exposed neurons had higher basal intracellular [Pi ], [ATP], and [GSH], and slightly lower cytosolic free [Ca2+ ], compared with Pi -deprived neurons. Pi -exposed neurons maintained increased [ATP] after exposure to NMDA and displayed reduced formation of reactive oxygen species after exposure to kainic acid or H2 O2 , compared with Pi -deprived neurons. These findings demonstrate that changes in extracellular and intracellular Pi can affect neuronal survival after excitotoxic or oxidative insults. 相似文献
997.
J. J. Ni P. Wu D. Senadhira N. Huang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(8):1361-1369
The amplified fragment length polymorphism (AFLP) technique combined with selective genotyping was used to map quantitative
trait loci (QTLs) associated with tolerance for phosphorus (P) deficiency in rice. P deficiency tolerant cultivar IR20 was
crossed to IR55178-3B-9-3 (sensitive to P-deficiency) and 285 recombinant inbred lines (RILs) were produced by single-seed
descent. The RILs were phenotyped for the trait by growing them in P-sufficient (10.0 mg/l) and P-deficient (0.5 mg/l) nutrient
solution and determining their relative tillering ability at 28 days after seeding, and relative shoot dry weight and relative
root dry weight at 42 days after seeding. Forty two of each of the extreme RILs (sensitive and tolerant) and the parents were
subjected to AFLP analysis. A map consisting of 217 AFLP markers was constructed. Its length was 1371.8 cM with an average
interval size of 7.62 cM. To assign linkage groups to chromosomes, 30 AFLP and 26 RFLP markers distributed over the 12 chromosomes
were employed as anchor markers. Based on the constructed map, a major QTL for P-deficiency tolerance, designated PHO, was
located on chromosome 12 and confirmed by RFLP markers RG9 and RG241 on the same chromosome. Several minor QTLs were mapped
on chromosomes 1, 6, and 9.
Received: 21 April 1998 / Accepted: 9 June 1998 相似文献
998.
Ni S Woese CR Aldrich HC Boone DR 《International journal of systematic bacteriology》1994,44(2):357-359
A sequence analysis of the 16S rRNA of Methanolobus siciliae T4/M(T) (T = type strain) showed that this strain is closely related to members of the genus Methanosarcina, especially Methanosarcina acetivorans C2A(T). Methanolobus siciliae T4/M(T) and HI350 were morphologically more similar to members of the genus Methanosarcina than to members of the genus Methanolobus in that they both formed massive cell aggregates with pseudosarcinae. Thus, we propose that Methanolobus siciliae should be transferred to the genus Methanosarcina as Methanosarcina siciliae. 相似文献
999.
Li Shuang Ni Yuqing Li Chen Xiang Qunyan Zhao Yan Xu Hui Huang Wu Wang Yanjiao Wang Yi Zhan Junkun Liu Youshuo 《Journal of physiology and biochemistry》2023,79(1):83-105
Journal of Physiology and Biochemistry - Long noncoding RNAs (lncRNAs) are emerging regulators of vascular diseases, yet their role in diabetic vascular calcification/aging remains poorly... 相似文献
1000.
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by immune abnormalities leading to multi-organ damage. The activation of autoreactive B cell differentiation will lead to the production of pathogenic autoantibodies, contributing to the development of SLE. However, the effects of Ophiopogonin D (OP-D) on B cell activation and autoantibody production as well as renal injury in the pathogenesis of SLE remain unclear. MRL/lpr mice, one of the most commonly used animal models of SLE, were intragastrically administered with 5 mg/kg/d OP-D at 17 weeks of age for 3 weeks. The survival rates of mice in each group were monitored for 6 weeks until 23 weeks of age. Proteinuria and serum creatinine levels were measured. Serum levels of immunoglobulin (Ig)G, IgM, and anti-dsDNA autoantibodies were detected by enzyme-linked immunosorbent assay. Numbers of CD19+ B cells in the blood, spleen and bone marrow and numbers of splenic germinal center (GC) B cells were calculated by using flow cytometry. OP-D treatment prolonged survival in MRL/lpr mice. OP-D treatment reduced proteinuria and serum creatinine levels as well as mitigated renal pathological alternation in MRL/lpr mice. Furthermore, serum levels of IgG, IgM, and anti-dsDNA autoantibodies were reduced by OP-D treatment. OP-D lessened not only CD19+ B cells in the spleen and bone marrow but also plasma cells that secreted anti-dsDNA autoantibodies, IgG and IgM in the spleen and bone marrow. OP-D ameliorated the progression of SLE by inhibiting the secretion of autoantibodies though reducing B cell numbers. 相似文献