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1.
A convenient large scale purification of the alpha-1 trypsin inhibitor from human plasma was achieved by conventional salting out and column chromatography methods. The pure inhibitor complexes 0.68 μgs of bovine trypsin per ug inhibitor, and 0.60 μgs human trypsin per μg inhibitor. The inhibitor is homogeneous by equilibrium chromatography, disc electrophoresis, and ultracentrifugation. Conditions for its storage with minimal loss of activity are described. The advantages of the present preparation are higher potency, long-term stability, and large scale.  相似文献   

2.
Abstract

Alpha-1 acid glycoprotein (or orosmucoid) was obtained in a pure state from normal human serum by ion exchange chromatography followed by curtain electrophoresis and a final ion exchange chromatography step. Pure α1 acid glycoprotein (α1A) has a sedimentation coefficient of 3.1 S and a diffusion coefficient of 5.2 × 10?7cm2 sec?1, which yields a molecular weight of 44,680 Daltons and an asymmetry factor of 14.6. The αA prepared in the manner here described appears less denatured than the same protein isolated by the Cohn fractionation method.1,2 ' Alpha-1 A acts as a depressant of phagocytosis3 and is one of the constituents of Mowbray's serum fraction,″which induces a prolongation of skin homografts.  相似文献   

3.
Horseradish peroxidase (HRP) and soybean peroxidase (SBP) were covalently immobilized onto aldehyde glass through their amine groups. The activity yield and the protein content for the immobilized SBP were higher than for the immobilized HRP. When free and immobilized peroxidases were tested for their ability to remove 4-chlorophenol from aqueous solutions, the removal percentages were higher with immobilized HRP than with free HRP, whereas immobilized SBP needs more enzyme to reach the same conversion than free enzyme. In the present paper the two immobilized derivatives are compared. It was found that at an immobilized enzyme concentration in the reactor of 15 mg l(-1), SBP removed 5% more of 4-chlorophenol than HRP, and that a shorter treatment was necessary. Since immobilized SBP was less susceptible to inactivation than HRP and provided higher 4-chlorophenol elimination, this derivative was chosen for further inactivation studies. The protective effect of the immobilization against the enzyme inactivation by hydrogen peroxide was demonstrated.  相似文献   

4.
Abstract: A simple method for the preparation of microvessels from the spinal cord is described. The fraction being enriched in the microvessels is characterized by morphological techniques and compared biochemically with the original suspension. The method makes possible detailed studies on the metabolism of microvessels and can be complementary to procedures that have been developed for separating the capillaries from other brain tissues.  相似文献   

5.
以人血清为原料 ,利用纤溶酶原对L型赖氨酸的高亲和性制备了Lysine -Sepharose4B和Lysine -Agarose ,以亲和层析法从人血浆中提取和纯化血纤溶酶原 (plasminogen ,PGn)。利用聚丙烯酰胺凝胶电泳对其纯度和分子量进行分析 ,结果表明纯化得到的为 92kDa的单一组分的人血纤溶酶原。这种纯化方法的建立为进一步大量制备血管生成抑制素 (angiostatin)奠定了基础。  相似文献   

6.

Background

The naked mole-rat (NMR) is a long-lived and cancer resistant species. Identification of potential anti-cancer and age related mechanisms is of great interest and makes this species eminent to investigate anti-cancer strategies and understand aging mechanisms. Since it is known that the NMR expresses higher liver mRNA-levels of alpha 2-macroglobulin than mice, nothing is known about its structure, functionality or expression level in the NMR compared to the human A2M.

Results

Here we show a comprehensive analysis of NMR- and human plasma-A2M, showing a different prediction in glycosylation of NMR-A2M, which results in a higher molecular weight compared to human A2M. Additionally, we found a higher concentration of A2M (8.3±0.44 mg/mL vs. and 4.4±0.20 mg/mL) and a lower total plasma protein content (38.7±1.79 mg/mL vs. 61.7±3.20 mg/mL) in NMR compared to human. NMR-A2M can be transformed by methylamine and trypsin resulting in a conformational change similar to human A2M. NMR-A2M is detectable by a polyclonal antibody against human A2M. Determination of tryptic and anti-tryptic activity of NMR and human plasma revealed a higher anti-tryptic activity of the NMR plasma. On the other hand, less proteolytic activity was found in NMR plasma compared to human plasma.

Conclusion

We found transformed NMR-A2M binding to its specific receptor LRP1. We could demonstrate lower protein expression of LRP1 in the NMR liver tissue compared to human but higher expression of A2M. This was accompanied by a higher EpCAM protein expression as central adhesion molecule in cancer progression. NMR-plasma was capable to increase the adhesion in human fibroblast in vitro most probably by increasing CD29 protein expression. This is the first report, demonstrating similarities as well as distinct differences between A2M in NMR and human plasma. This might be directly linked to the intriguing phenotype of the NMR and suggests that A2M might probably play an important role in anti-cancer and the anti-aging mechanisms in the NMR.  相似文献   

7.
Mammalian somatic cells are usually diploid. Occasional rare human tumors have been shown to have a hypodiploid karyotype. We have isolated a near-haploid subclone (P1-55) from a heterogeneous human leukemia cell line, KBM-7. These near-haploid cells have approximately half the human diploid DNA content and have a haploid karyotype except for a disomy of chromosome 8 (25, XY, +8, Ph(+)). This cell line maintains a majority of cells with a near-haploid karyotype for at least 12 weeks in culture. By serial subcloning, we have isolated near-haploid subclones that maintain ploidy for at least 8 months in culture. Near-haploid cells can also be efficiently isolated from mixed ploidy cultures by size selection. The availability of this human near-haploid cell line should facilitate the genetic analysis of cultured human cells.  相似文献   

8.
Cytokinin-binding protein (CBPI) was purified from the watersoluble fraction of tobacco leaves by successive chromatographyon benzyladenine-linked (BA-linked) Sepharose 4B, TSK-Gel G3000SWXL,t-zeatin-linked Sepharose 6B and TSK-Gel G3000SWXL. CBPI wasobtained as a monomer with a molecular weight of 31 kDa. Ithas one cytokinin-binding site, which shows a high affinityfor BA (Kd=1.1x10–7 M) and other cytokinins. Biologicallyactive cytokinins competed with BA for binding to this protein,while biologically inactive analogues of adenine did not. Inall cases, cytokinin-binding activity was assayed by equilibriumdialysis. 1 Present address: National Institute for Basic Biology, Okazaki,444 Japan.  相似文献   

9.
Pregnancy is characterized by the infiltration of leukocytes in the reproductive tissues and at the maternal-fetal interface (decidua basalis and decidua parietalis). This interface is the anatomical site of contact between maternal and fetal tissues; therefore, it is an immunological site of action during pregnancy. Infiltrating leukocytes at the maternal-fetal interface play a central role in implantation, pregnancy maintenance, and timing of delivery. Therefore, phenotypic and functional characterizations of these leukocytes will provide insight into the mechanisms that lead to pregnancy disorders. Several protocols have been described in order to isolate infiltrating leukocytes from the decidua basalis and decidua parietalis; however, the lack of consistency in the reagents, enzymes, and times of incubation makes it difficult to compare these results. Described herein is a novel approach that combines the use of gentle mechanical and enzymatic dissociation techniques to preserve the viability and integrity of extracellular and intracellular markers in leukocytes isolated from the human tissues at the maternal-fetal interface. Aside from immunophenotyping, cell culture, and cell sorting, the future applications of this protocol are numerous and varied. Following this protocol, the isolated leukocytes can be used to determine DNA methylation, expression of target genes, in vitro leukocyte functionality (i.e., phagocytosis, cytotoxicity, T-cell proliferation, and plasticity, etc.), and the production of reactive oxygen species at the maternal-fetal interface. Additionally, using the described protocol, this laboratory has been able to describe new and rare leukocytes at the maternal-fetal interface.  相似文献   

10.
Abstract

A procedure for purification of the bungarotoxin-binding fraction of sarcolemma from rabbit skeletal muscle is described. Muscle is homogenized in 0.25M sucrose without high salt extraction and membrane fractions separated initially by differential centrifugation procedures. An ultracentrifugation pellet enriched in cell surface and sarcoplasmic reticulum markers is further fractionated on a dextran gradient (density = 1.0 to 1.09). Two fractions are identified as sarcolemma according to high specific activities for lactoperoxidaseiodination, Na+, K+-ATPase and α-bungarotoxin-binding. No Ca++, Mg++-ATPase activity is found in these fractions. A third fraction, the dextran gradient pellet, is enriched in Ca++, Mg++-ATPase activity and lactoperoxidase iodinatable material and characterized by low bungarotoxin binding. This fraction represents a mixture of sarcoplasmic reticulum and transverse tubules with some sarcolemma contamination.  相似文献   

11.
Tubular structures are released from cells of Cytophaga columnaris after lysis of the cells. To determine the nature of these tubules, they were purified and their composition was determined. Tubules were isolated after treating cell lysates with 1.0% sodium dodecyl sulfate at pH 8.1, which solubilizes all structural components except tubules. Plasma membranes from the same organism were isolated by discontinuous sucrose gradient centrifugation of lysed cells. Both tubules and membranes are composed of lipids and proteins. Lipids extracted from tubules and plasma membranes produced similar patterns when examined by thin-layer chromatography. Proteins solubilized from membranes were separated into 14 bands by polyacrylamide gel electrophoresis, whereas those solubilized from tubules separated into only 5 bands. The presence of lipids in tubules from C. columnaris supports the idea that they are derived from membranes of intact cells. In this respect they are similar to tubules produced by cells of Clostridium botulinum and different from other tubular structures ("rhapidosomes") found in cells of Saprospira grandis.  相似文献   

12.
We report a method for the isolation of enriched fractions of intact Golgi apparatus from neurons of 10- to 12-day-old rat brains. Neurons were prepared according to a modified method of Farooq and Norton [J. Neurochem. 31, 887-894 (1978)]. Golgi-enriched fractions were obtained after centrifugation of postmitochondrial supernatants in a discontinuous sucrose gradient. Golgi fractions 1 and 2, recovered at the interfaces of 28-34% and 34-36% sucrose densities, respectively, were examined with morphometric and enzymatic methods. Morphometric analyses showed that 21-34% of fraction 1 and 11-29% of fraction 2 consisted of intact Golgi apparatus. Lysosomes, mitochondria, ribosomes, and rough endoplasmic reticulum contaminated fraction 1 (6-10%) and fraction 2 (14-26%). Golgi fraction 1 showed a 25- to 65-fold enrichment over neurons of UDP Gal:GlcNAc galactosyltransferase, CMP-sialic acid:lactosylceramide sialyltransferase, and PAPS:cerebroside sulfotransferase activities. Golgi fraction 2 showed a 8- to 23-fold enrichment over neurons of the activities of the above glycolipid- and glycoprotein-synthesizing enzymes. The activities of the possible marker enzymes rotenone-insensitive NADH-cytochrome c reductase, succinate-cytochrome c reductase, and arylsulfatase were low or minimally elevated in the Golgi fractions. A sevenfold enrichment of Na+, K+-ATPase activities was found in the Golgi fractions. This is consistent either with significant plasma membrane contamination or with the presence of this enzyme in the neuronal Golgi apparatus.  相似文献   

13.
A method for the effective isolation of functionally intact phycobilisomes from the thermophilic cyanobacterium M. laminosus is presented, using an unconventional high buffer molarity for stabilizing the aggregates and introducing a DNAse treatment of the disrupted cells to obtain sharp banding of the phycobilisomes in the linear sucrose density gradients.The structural integrity of the isolated phycobilisomes is demonstrated by a fluorescence emission maximum at 673 nm of aggregated allophycocyanin and by electron microscopy.Besides C-phycocyanin and allophycocyanin, phycoerythrocyanin is a constituent pigment of the phycobilisomes. These pigments indicated in the absorption spectrum of phycobilisomes with a maximum at 610 nm and two shoulders at 650 and 580 nm, respectively, were characterized by spectral data and isoelectric points.  相似文献   

14.
15.
Abstract Morphological and physiological properties of Tetrahymena thermophila immobilized by encapsulation in calcium-alginate hollow spheres were found to be substantially different from those of suspended cells. Immobilized T. thermophila reached lengths of 70–100 μm, whereas the average cell of suspension cultures was about 40 μm long. Suspended cells appeared typically pear-shaped while immobilized cells developed a proboscis-like anterior end. Contrary to suspended T. thermophila , encapsulated cells were functionally deficient in phagocytosis although developing an oral apparatus. The diameter of the macronucleus of immobilized cells was about two times larger than the macronucleus of suspended cells and contained twice as much DNA, while the DNA content of the micronucleus remained unchanged. High cell density fermentations of suspended cells indicated that the alterations observed in immobilized cells were not due to close physical contacts between the cells.  相似文献   

16.
An equol-producing bacterium was newly isolated from the feces of healthy humans and its morphological and biochemical properties were characterized. The cells were obligate anaerobes. They were non-sporulating, non-motile, gram-positive bacilliform bacteria with a pleomorphic morphology. The strain was catalase-positive, and oxidase-, urease-, and indole-negative. The only other sugar utilized by the strain was glycerin. The strain also degraded gelatin, but not esculin. It was most closely related to Eggerthella hongkongensis HKU10, with 93.3% 16S rDNA nucleotide sequence homology. Based on these features, the isolate was identified as a novel species of the genus Eggerthella. It was named Eggerthella sp. YY7918. Strain YY7918 converted substrates daidzein and dihydrodaidzein into S-equol, but did not convert daidzin, glysitein, genistein, or formononetin into it. An antimicrobial susceptibility assay indicated that strain YY7918 was susceptible to aminoglycoside-, tetracycline-, and new quinolone-antibiotics.  相似文献   

17.
Cellular pathways of normal and reparative differentiation of upper airway epithelium are not well understood. Of the three main cell types, basal and secretory cells are known to divide, while ciliated cells are considered terminally differentiated. Several investigations support the role of the basal cell as a progenitor cell type, but others suggest that the secretory cell can regenerate a complete mucocilliary epithelium. Thus, lineage relationships within renewing adult epithelia are still unclear. Understanding the pathways involved in upper airway epithelial cell differentiation is critical for studying injury and repair mechanisms and for developing clinical strategies for tracheal reconstruction. We undertook the current studies to determine the integrin profile of isolated human upper airway basal cells. Respiratory epithelial cells (REC) were isolated by elastase digestion, stained with FITC-labeledGriffonia simplicifoliaisolectin B4(GSI-B4), and sorted by flow cytometry. Approximately 80% of the lectin-positive cells were basal cells, as determined by morphology and cytokeratin staining. These cells expressed integrins α1, α2, α3, α5, αvβ5, β1, β3, and α6β4, by immunohistochemistry. This is the first report to identify the integrin profile of isolated human upper airway basal cells. These basal cells could be maintained on type I collagen for at least 7 days, where they became partially confluent and retained expression of cytokeratins 5 and 14. Availability of pure populations of basal cells should permit investigations of their role in both normal and maladaptive repair of adult upper airway epithelium.  相似文献   

18.
从水稻基因组文库中筛选得到一个水稻GST基因,命名为OsGSTL1.半定量RT-PCR分析表明OsGSTL1基因的表达不受绿磺隆、乙烯利、脱落酸、水杨酸和茉莉酸甲酯的诱导,因此该基因可能与植物抗逆性无关.为了研究OsGSTL1启动子在植物体内的表达特性,将OsGSTL1起始位点5'端上游不同长度的调控序列与报告基因GUS融合,并在洋葱表皮瞬间表达和拟南芥中稳定表达.研究表明:在洋葱表皮细胞中,160bp及更长的上游调控序列均能启动GUS基因的表达;而在转基因拟南芥中,含有2155 bp的上游序列的PGZ2.1::GUS具有时空表达的特性,在转基因的早期幼苗中GUS基因在子叶中特异性表达,但在根中没有表达;而在幼苗生长的后期,根、茎、叶中都有少量的表达.但包含1 224 bp的上游序列的PGZ1.2::GUS却表现为组成型表达的特性.由此推测,OsGSTL1启动子启动的基因表达可能与幼苗的营养代谢相关;而OsGSTL1启动子的时空表达相关元件可能位于OsGSTL1翻译起始位点5'端上游-2155 bp至-1224 bp范围内.  相似文献   

19.
A new method for isolation of the constitutive heterochromatin (chromocenters) from interphase nuclei of mouse liver has been developed. This method allows separation of chromocenters of different size. Chromocenter fractions are essentially free of nucleoli and other contaminants. In contrast to nuclei and nucleoli, the chromocenter fraction is characterized by simpler protein composition, this fraction having a reduced number of proteins (especially high molecular weight proteins). Chromocenters contain all histone fractions; however, the relative proportion of histone H1 is lower and histone H3 is higher than in the total nuclear chromatin. The amount of non-histone proteins of 51, 63, 73, and 180 kD is higher in the chromocenter fraction than in nuclei and nucleoli. The use of immunocytochemistry and immunoblotting methods revealed the presence of the specific kinetochore component, CENP A protein. This suggests tight association of some molecular kinetochore components with chromocenters in the interphase.  相似文献   

20.
胎儿肺脏来源间充质干细胞的鉴定与损伤修复的实验研究   总被引:2,自引:0,他引:2  
目的 :为研究胎儿肺脏来源间充质干细胞的生物学性状 ,表型和多向分化能力。方法 :取胎龄为 4~ 5个月水囊引产胎儿 ,将肺脏细胞在SF(含 2 %FBS)培养基中培养。测定生长曲线、利用流式细胞仪对培养细胞进行表型测定 ,细胞周期分析 ,体外诱导分化实验。NOD SCID鼠放射损伤后 ,尾静脉输入经PKH2 6染色的间充质干细胞 ,两个月后检测外源细胞在肺脏的定植情况。结果 :从胎儿肺脏可培养出间充质干细胞 ,并可诱导成骨、软骨和脂肪细胞分化 ;移植两个月后可以检测到外源细胞在肺脏的定植。结论 :从胎儿肺脏可分离培养出间充质干细胞 ,在体外有效扩增且保持其低分化状态 ;间充质干细胞可以在肺脏长时间定植。  相似文献   

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