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101.
Mesenchymal Stem Cells from Rat Bone Marrow Downregulate Caspase-3-mediated Apoptotic Pathway After Spinal Cord Injury in Rats 总被引:6,自引:0,他引:6
Mesenchymal stem cells have been intensively studied for their potential use in reparative strategies for neurodegenerative
diseases and traumatic injuries. We used mesenchymal stem cells (rMSC) from rat bone marrow to evaluate the therapeutic potential
after spinal cord injury (SCI). Immunohistochemistry confirmed a large number of apoptotic neurons and oligodendrocytes in
caudal segments 2 mm away from the lesion site. Expression of caspase-3 on both neurons and oligodendrocytes after SCI was
significantly downregulated by rMSC. Caspase-3 downregulation by rMSC involves increased expression of FLIP and XIAP in the
cytosol and inhibition of PARP cleavage in the nucleus. Animals treated with rMSC had higher Basso, Beattie, Bresnahan (BBB)
locomotor scoring and better recovery of hind limb sensitivity. Treatment with rMSC had a positive effect on behavioral outcome
and histopathological assessment after SCI. The ability of rMSC to incorporate into the spinal cord, differentiate and to
improve locomotor recovery hold promise for a potential cure after SCI.
Special issue in honor of Naren Banik. 相似文献
102.
Suppression of gene expression by small interfering RNA (siRNA) has proved to be a gene-specific and cost effective alternative
to other gene suppression technologies. Short hairpin RNAs (shRNAs) generated from the vector-based expression are believed
to be processed into functional siRNAs in vivo, leading to gene silencing. Since an shRNA library carries a large pool of potential siRNAs, such a library makes it possible
to knock down gene expression at the genome wide scale. Although much of research has been focused on generating shRNA libraries
from either individually made gene specific sequences or cDNA libraries, there is no report on constructing randomized shRNA
libraries, which could provide a good alternative to these existing libraries. We have developed a method of constructing
shRNAs from randomized oligonucleotides. Through this method, one can generate a partially or fully randomized shRNA library
for various functional analyses. We validated this procedure by constructing a p53-specific shRNA. Western blot revealed that
the p53-shRNA successfully suppressed expression of the endogenous p53 in MCF-7 cells. We then made a partially randomized
shRNA library. Sequencing of 15 randomly picked cloned confirmed the randomness of the library. Therefore, the library can
be used for various functional assays, such as target validation when a suitable screening or selection method is available. 相似文献
103.
Binh Tran Quang Linh Duong Tuan Chung Le Thi Kim Phuong Pham Tran Nga Bui Thi Thuy Ngoc Nguyen Anh Thuyen Tran Quang Tung Do Dinh Nhung Bui Thi 《Biochemical genetics》2022,60(2):707-719
Biochemical Genetics - The study aimed to evaluate the contribution of the FTO A/T polymorphism (rs9939609) to the prediction of the future type 2 diabetes (T2D). A population-based prospective... 相似文献
104.
105.
Nguyen Anh T. Q. Nguyen Anh M. Nguyen Muu T. Nguyen Hue T. Duong Lim T. Dinh Van M. Nguyen Phuong M. Dultz Stefan Nguyen Minh N. 《Biogeochemistry》2022,160(1):35-47
Biogeochemistry - Phytolith is widely known as a silica structure in numerous silicon (Si) accumulator plants, e.g., rice, and it contains various nutrients and other beneficial elements. When rice... 相似文献
106.
Live cell imaging compatible immobilization of Chlamydomonas reinhardtii in microfluidic platform for biodiesel research
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107.
108.
Tran DT Vermeeren V Grieten L Wenmackers S Wagner P Pollet J Janssen KP Michiels L Lammertyn J 《Biosensors & bioelectronics》2011,26(6):2987-2993
Like antibodies, aptamers are highly valuable as bioreceptor molecules for protein biomarkers because of their excellent selectivity, specificity and stability. The integration of aptamers with semiconducting materials offers great potential for the development of reliable aptasensors. In this paper we present an aptamer-based impedimetric biosensor using a nanocrystalline diamond (NCD) film as a working electrode for the direct and label-free detection of human immunoglobulin E (IgE). Amino (NH(2))-terminated IgE aptamers were covalently attached to carboxyl (COOH)-modified NCD surfaces using carbodiimide chemistry. Electrochemical impedance spectroscopy (EIS) was applied to measure the changes in interfacial electrical properties that arise when the aptamer-functionalized diamond surface was exposed to IgE solutions. During incubation, the formation of aptamer-IgE complexes caused a significant change in the capacitance of the double-layer, in good correspondence with the IgE concentration. The linear dynamic range of IgE detection was from 0.03 μg/mL to 42.8 μg/mL. The detection limit of the aptasensor reached physiologically relevant concentrations (0.03 μg/mL). The NCD-based aptasensor was demonstrated to be highly selective even in the presence of a large excess of IgG. In addition, the aptasensor provided reproducible signals during six regeneration cycles. The impedimetric aptasensor was successfully tested on human serum samples, which opens up the potential of using EIS for direct and label-free detection of IgE levels in blood serum. 相似文献
109.
110.
We have developed a simple approach for generating peptide-conjugated gold nanoparticles (AuNPs) from the Rev peptide and gold aqueous solution. The peptide functions as both a reducing agent and a capping molecule. AuNPs of various sizes (20-300 nm) and shapes (spheres, triangular plates, and polygons) can be obtained upon modulating the ratio of gold ions to the Rev peptide. Transmission electron microscopy, X-ray diffraction, and UV-vis spectroscopy were utilized to characterize these nanoparticles. Fourier-transform infrared and X-ray photoelectron spectroscopy measurements were performed to investigate chemical interactions between the Rev peptide and AuNPs. Lactate dehydrogenase and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays revealed that the Rev peptide-AuNP nanocomposites exhibited exceptionally high cytotoxic effects toward mouse ovarian surface epithelial cell lines, relative to the effects of equal doses of the free Rev peptide. Our study suggests a new way of utilizing biomolecule-conjugated AuNPs as potentially effective anticancer drugs. 相似文献