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101.
Multiplexed genotyping with sequence-tagged molecular inversion probes 总被引:19,自引:0,他引:19
Hardenbol P Banér J Jain M Nilsson M Namsaraev EA Karlin-Neumann GA Fakhrai-Rad H Ronaghi M Willis TD Landegren U Davis RW 《Nature biotechnology》2003,21(6):673-678
We report on the development of molecular inversion probe (MIP) genotyping, an efficient technology for large-scale single nucleotide polymorphism (SNP) analysis. This technique uses MIPs to produce inverted sequences, which undergo a unimolecular rearrangement and are then amplified by PCR using common primers and analyzed using universal sequence tag DNA microarrays, resulting in highly specific genotyping. With this technology, multiplex analysis of more than 1,000 probes in a single tube can be done using standard laboratory equipment. Genotypes are generated with a high call rate (95%) and high accuracy (>99%) as determined by independent sequencing. 相似文献
102.
Mirhendi H Makimura K Zomorodian K Yamada T Sugita T Yamaguchi H 《Journal of microbiological methods》2005,61(2):281-284
A PCR-RFLP method targeted toward 26S rDNA and with 2 restriction enzymes, CfoI and BstF51, was developed to identify 11 Malassezia species. Not only type and standard strains but also 13 clinical isolates were identified successfully in this study. The results of identifications were confirmed by DNA sequencing. 相似文献
103.
Mohammadian-Mosaabadi J Naderi-Manesh H Maghsoudi N Nassiri-Khalili MA Masoumian MR Malek-Sabet N 《Protein expression and purification》2007,51(2):147-156
Process development and optimization studies were performed in order to improve the purification process of (rhIFN-gamma). The objective was to generate material with higher purity and quantity. An in-process control screening was developed to obtain the optimal condition for column chromatographic purification by measuring LPS, nucleic acids, rhIFN- gamma, monomer and its covalent dimers. A new resin screening method was applied to select optimal resin for each of the chromatographic columns. The resulting process used Butyl and Q-Sepharose, refolding and SP-Sepharose for purification of IFN-gamma. Effects of different process conditions such as cell lysis, removal of impurity and oxygen concentration were evaluated. Removal of impurities was evaluated by washing of inclusion bodies with 1% Triton X-100 and 3M urea and different chromatography steps. The results reveal that Triton removed about 43% of the LPS but urea had no effect on removal of nucleic acids and LPS. Further analysis show that removal of impurities by column chromatography decreases aggregation and increases the process yield. Oxygen concentration was identified as parameter that could have a significant impact on covalent dimers formation, as an unacceptable pharmaceutical form of rhIFN-gamma. On the basis of small-scale studies, optimum operating conditions were chosen and the purification process was successfully scaled-up to a pilot scale process with step yield and product quality that were better than previous reports. 相似文献
104.
Mohammad Hossein Soleimani Majid Talebi Badraldin Ebrahim Sayed-Tabatabaei 《Plant Systematics and Evolution》2012,298(6):1141-1149
Sequence-related amplified polymorphism (SRAP) was used to assess the genetic diversity of 63 cultivated, wild, and ornamental pomegranate genotypes from five different geographical regions of Iran. A total of 250 fragments were amplified using 13 primer combinations; among these, 133 bands (53?%) were polymorphic. The average PIC value was 0.28 over all PCs. The genetic distance among genotypes ranged from 0.10 to 0.37 with an average of 0.24. Cluster analysis using the neighbor-joining (NJ) method suggested there are close relationships between ornamental and some wild genotypes. Although AMOVA results revealed significant differences in the genetic diversity among the regions (P?=?0.0048), the genetic variation was mainly caused by variation of intra regions. The results indicated low genetic differentiation (Fst?=?0.025) and high gene flow (Nm?=?2.28) among regions. These results confirmed that SRAP markers could be powerful tools and an effective marker system for determining the genetic diversity and population genetic structure of the pomegranate. 相似文献
105.
Mehdi Imani Yaser Bahrami Hossein Zarei Jaliani Sussan Kaboudanian Ardestani 《The protein journal》2014,33(5):465-473
Calprotectin (CP) is widely considered to have diverse roles including growth inhibitory and apoptosis induction in a number of tumor cell lines and antimicrobial activities. As CP has been proposed to bind metal ions with high affinity, we have studied its functional and primarily its structural behavior upon Zn2+ and Mn2+ chelation solely and along with Ca2+. We employed fluorescence spectroscopy and circular dichroism to determine the resulting modifications. Based upon our findings it is clear that treating CP with ions effectively weakened its natural growth inhibitory activity. Moreover, structural analysis of Zn2+ and Mn2+-treated CPs indicated remarkable alterations in the regular secondary structures in favor of irregular structures while Zn2+ and Mn2+ treatment of CP after incubation with Ca2+ displayed no remarkable shifts. Tertiary structure investigation using fluorescence spectroscopy showed that CP undergoes conformational changes upon Zn2+ and Mn2+ treatment whereby Trp residues of protein is slightly exposed to the hydrophilic environment, compactness of CP is compromised, whereas in Ca2+-treated CP, the tertiary structure integrity is intact upon Zn2+ and Mn2+ chelation. Interestingly, CP structural modifications upon Zn2+ and Mn2+ treatment was significantly comparable, probably due to similar radii and charges of ions. Taken all together, we have concluded that CP maintains its normal nature in Ca2+-loaded state when treated with Zn2+ and Mn2+ ions. It can be suggested that Ca2+ not only stabilize CP structure but also helps CP to keep its structure upon metal ions chelation which is involved in host organism defense system. 相似文献
106.
Divsalar A Saboury AA Mansoori-Torshizi H Moghaddam MI Ahmad F Hakimelahi GH 《Journal of biomolecular structure & dynamics》2009,26(5):587-597
Abstract An new water-soluble Pd(II) complex, 2,2'-bipyridin n-butyl dithiocarbamato Pd(II) nitrate has been synthesized. The Pd(II) complex has been characterized by elemental analysis and conductivity measurements as well as spectroscopic methods such as infrared, 1H NMR, and ultraviolet-visible. The interaction between this new design Pd(II)-complex, an anti-tumor component, with carrier proteins of β-lactoglobulin-A and -B (BLG-A and -B) were studied at different temperatures of 27, 37, 42, and 47 °C by fluorescence spectroscopy and far-UV circular dichroism (CD) spectrophotometric techniques. A strong fluorescence quenching interaction of Pd(II) complex with BLG-A and -B was observed at different temperatures. The binding parameters were evaluated by fluorescence quenching method. The thermodynamic parameters, including ΔH°, ΔS°, and ΔG° were calculated by fluorescence quenching method indicated that the electrostatic and hydrophobic forces might play a major role in the interactions of Pd(II) complex with BLG-A and -B, respectively. The distances between donors (Trps of the BLG-A and -B) and acceptor (Pd(II) complex) were obtained according to the fluorescence resonance energy transfer (FRET). Far-UV CD studies showed that the Pd(II) complex did not represent any significant changes in the secondary structures of BLG- A and -B. The difference in the interaction properties observed for BLG-A and -B with Pd(II) complex is related to the difference in the amino acid sequences between these two variants. 相似文献
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109.
Many properties of connective tissues are governed by the organization of the constituent collagen. For example, the organization of collagen in the cornea and the limbus, where the cornea and sclera meet, is an important determinant of corneal curvature and hence of the eye's focusing power. We have used synchrotron X-ray scattering to map the orientation of the collagen fibrils throughout the human cornea, limbus, and adjacent sclera. We demonstrate a preferred orientation of collagen in the vertical and horizontal directions that is maintained to within about 1 mm from the limbus, where a circular or tangential disposition of fibrils occurs. The data are also used to map the relative distribution of both the total and the preferentially aligned collagen in different parts of the tissue, revealing considerable anisotropy. The detailed structural information provided is an important step toward understanding the shape and the mechanical properties of the tissue. 相似文献
110.
Mesenchymal stem cells (MSCs) are a major component of various forms of tissue engineering. MSCs have self-renewal and multidifferential potential. Osteogenic differentiation of MSCs is an area of attention in bone regeneration. One form of MSCs are adipose-derived stem cells (ASCs), which can be simply harvested and differentiated into several cell lineages, such as chondrocytes, adipocytes, or osteoblasts. Due to special properties, ASCs are frequently used in vitro and in vivo bone regeneration. Identifying factors involved in osteogenic differentiation of ASCs is important for better understanding the mechanism of osteogenic differentiation. Different methods are used to stimulate osteogenesis of ASCs in literature, including common osteogenic media, growth factors, hormones, hypoxia, mechanical and chemical stimuli, genetic modification, and nanotechnology. This review article provides an overview describing the isolation procedure, characterization, properties, current methods for osteogenic differentiation of ASCs, and their basic biological mechanism. 相似文献