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61.
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
62.
Yeast two-hybrid and Far Western analyses were used to detect interactions between Bacillus subtilis spores' nutrient germinant receptor proteins and proteins encoded by the spoVA operon, all of which are involved in spore germination and located in the spores' inner membrane. These analyses indicated that two subunits of the GerA nutrient germinant receptor interact, consistent with previous genetic data, and that some GerA proteins interact with SpoVAD and some with SpoVAE. SpoVA proteins appear to be involved in the release of the spore's dipicolinic acid during spore germination, an event triggered by the binding of nutrient germinants to their receptors. Consequently, these new findings suggest that nutrient germinant receptors physically contact SpoVA proteins, and presumably this is a route for signal transduction during spore germination. 相似文献
63.
Gao Xiang Uno Kenichi Sarr Papa Saliou Yoshihashi Tadashi Zhu Yiyong Subbarao Guntur Venkata 《Plant and Soil》2022,477(1-2):793-805
Plant and Soil - Rapid nitrification leads to loss of nitrogen (N) fertilizer in agricultural systems. Plant produced/derived biological nitrification inhibitors (BNIs) are an effective... 相似文献
64.
65.
Gopinath Kulasekaran Nadya Nossova Andrea L. Marat Ingrid Lund Christopher Cremer Maria S. Ioannou Peter S. McPherson 《The Journal of biological chemistry》2015,290(29):17999-18008
Connecdenn 1/2 are DENN (differentially expressed in normal and neoplastic cells) domain-bearing proteins that function as GEFs (guanine nucleotide exchange factors) for the small GTPase Rab35. Disruption of connecdenn/Rab35 function leads to defects in the recycling of multiple cargo proteins from endosomes with altered cell function, yet the regulation of connecdenn GEF activity is unexplored. We now demonstrate that connecdenn 1/2 are autoinhibited such that the purified, full-length proteins have significantly less Rab35 binding and GEF activity than the isolated DENN domain. Both proteins are phosphorylated with prominent phosphorylation sites between residues 500 and 600 of connecdenn 1. A large scale proteomics screen revealed that connecdenn 1 is phosphorylated at residues Ser-536 and Ser-538 in an Akt-dependent manner in response to insulin stimulation of adipocytes. Interestingly, we find that an Akt inhibitor reduces connecdenn 1 interaction with Rab35 after insulin treatment of adipocytes. Remarkably, a peptide flanking Ser-536/Ser-538 binds the DENN domain of connecdenn 1, whereas a phosphomimetic peptide does not. Moreover, connecdenn 1 interacts with 14-3-3 proteins, and this interaction is also disrupted by Akt inhibition and by mutation of Ser-536/Ser-538. We propose that Akt phosphorylation of connecdenn 1 downstream of insulin activation regulates connecdenn 1 function through an intramolecular interaction. 相似文献
66.
Virus‐induced gene silencing of Withania somnifera squalene synthase negatively regulates sterol and defence‐related genes resulting in reduced withanolides and biotic stress tolerance
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67.
Marimuthu Citartan Thean-Hock Tang Soo-Choon Tan Subash C. B. Gopinath 《World journal of microbiology & biotechnology》2011,27(5):1167-1173
The generation of DNA aptamer by Systematic Evolution of Ligands by Exponential Enrichment requires a good method of ssDNA
generation. There are various methods developed to generate ssDNA such as streptavidin-biotin based separation techniques,
asymmetric PCR and strand separation of the PCR product containing primer with a terminator and an extension of 20 nucleotides
on denaturing urea-polyacrylamide gel. In the present investigation, we have shown the possible improvements for the regular
lambda nuclease digestion under optimized conditions. Optimization of the PCR cycles, time course studies on lambda nuclease
digestion and purification of the ssDNA from the lambda exonuclease digestion mixture was found to be able to recover ssDNA
amounting up to 39.19 ± 2.48 % of the starting amount of dsDNA. These strategies can be applied to the techniques involving
essential usage of ssDNA. 相似文献
68.
Gopinath KP Kathiravan MN Srinivasan R Sankaranarayanan S 《Bioresource technology》2011,102(4):3687-3693
In this study, it was attempted to evaluate the influences and also recommended some elimination methods for inhibitory effects offered by salts and heavy metal ions. Congo red dye solution treated with mutant Pseudomonas sp. was taken as a model system for study. The salts used in this study are NaCl, CaCl2 and MgSO4·7H2O. Though the growth was inhibited at concentrations above 4 g/l, toleration was achieved by acclimatization process. In case of heavy metal ions, Cr (VI) showed low inhibition up to 500 mg/l of concentration, compared to Zn (II) and Cu (II). It was due to the presence of chromium reductase enzyme which was confirmed by SDS-PAGE. Zn (II) and Cu (II) ion inhibitions were eliminated by chelation with EDTA. The critical ion concentrations obtained as per Han-Levenspiel model for Cr (VI), Zn (II) and Cu (II) were 0.8958, 0.3028 and 0.204 g/l respectively. 相似文献
69.
Pallapolu VR Lee YY Garlock RJ Balan V Dale BE Kim Y Mosier NS Ladisch MR Falls M Holtzapple MT Sierra-Ramirez R Shi J Ebrik MA Redmond T Yang B Wyman CE Donohoe BS Vinzant TB Elander RT Hames B Thomas S Warner RE 《Bioresource technology》2011,102(24):11115-11120
The objective of this work is to investigate the effects of cellulase loading and β-glucosidase supplementation on enzymatic hydrolysis of pretreated Dacotah switchgrass. To assess the difference among various pretreatment methods, the profiles of sugars and intermediates were determined for differently treated substrates. For all pretreatments, 72 h glucan/xylan digestibilities increased sharply with enzyme loading up to 25 mg protein/g-glucan, after which the response varied depending on the pretreatment method. For a fixed level of enzyme loading, dilute sulfuric acid (DA), SO2, and Lime pretreatments exhibited higher digestibility than the soaking in aqueous ammonia (SAA) and ammonia fiber expansion (AFEX). Supplementation of Novozyme-188 to Spezyme-CP improved the 72 h glucan digestibility only for the SAA treated samples. The effect of β-glucosidase supplementation was discernible only at the early phase of hydrolysis where accumulation of cellobiose and oligomers is significant. Addition of β-glucosidase increased the xylan digestibility of alkaline treated samples due to the β-xylosidase activity present in Novozyme-188. 相似文献
70.
Ram Reddy T Srinivasula Reddy L Rajeshwar Reddy G Nuthalapati VS Lingappa Y Sandra S Kapavarapu R Misra P Pal M 《Bioorganic & medicinal chemistry letters》2011,21(21):6433-6439
A multi component based synthesis involving palladium catalyzed C-C bond forming reaction has been developed as a new strategy to access systematically modified functionalized 2-aminochromenes. This MCR involves the use of bromobenzaldehyde as a key component and is highlighted by generating a new compound library. Many of these compounds showed Mycobacterium tuberculosis H37Rv chorismate mutase inhibiting properties in vitro representing the lead example of chorismate mutase inhibition by heteroarene based compounds. 相似文献