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151.
Y Chao D Singh L Yu Z Li Z Chi S Chen 《World journal of microbiology & biotechnology》2012,28(8):2635-2641
Trichoderma reesei is an important cellulase producer and its secondary mycelial phase is responsible for cellulase expression and secretion in submerged fermentation. Little is known regarding the effects of fungal morphology on cellulase production by Trichoderma sp. In this study we aimed to extend the understanding of cellulase production by T. reesei, especially correlating cellulase productivity with pellet morphology and with its secretome characteristics. We found that T. reesei was more likely to form pellets in malt extract broth than in potato dextrose broth. CaCO(3) helped in formation of fine pellets in malt extract broth. 10(9) spores/ml resulted in formation of pellets with the size of 0.13 ± 0.047 mm. LC/MS spectrometry analysis indicated that the secretomes from pellet was different from that of mycelial mat under the same fermentation conditions. Optimization tests showed that lactose, xylose and Pluronic F68 are important for efficient production of cellulases with FPU activity in the pellets fermentation. This is the first report on the artificial formation of pellets by Trichoderma sp. as well as correlation between physiological characteristic of the pellets and cellulase production by T. reesei. The findings from this study can be used for improvement of cellulase productivity. 相似文献
152.
Boys ML Bian F Kramer JB Chio CL Ren XD Chen H Barrett SD Sexton KE Iula DM Filzen GF Nguyen MN Angell P Downs VL Wang Z Raheja N Ellsworth EL Fakhoury S Bratton LD Keller PR Gowan R Drummond EM Maiti SN Hena MA Lu L McConnell P Knafels JD Thanabal V Sun F Alessi D McCarthy A Zhang E Finzel BC Patel S Ciotti SM Eisma R Payne NA Gilbertsen RB Kostlan CR Pocalyko DJ Lala DS 《Bioorganic & medicinal chemistry letters》2012,22(10):3392-3397
A series of 2-(1H-pyrazol-1-yl)pyridines are described as inhibitors of ALK5 (TGFβ receptor I kinase). Modeling compounds in the ALK5 kinase domain enabled some optimization of potency via substitutions on the pyrazole core. One of these compounds PF-03671148 gave a dose dependent reduction in TGFβ induced fibrotic gene expression in human fibroblasts. A similar reduction in fibrotic gene expression was observed when PF-03671148 was applied topically in a rat wound repair model. Thus these compounds have potential utility for the prevention of dermal scarring. 相似文献
153.
A Husain M Rashid R Mishra S Parveen DS Shin D Kumar 《Bioorganic & medicinal chemistry letters》2012,22(17):5438-5444
Two new series of benzimidazole bearing oxadiazole[1-(1H-benzo[d]imidazol-2-yl)-3-(5-substituted-1,3,4-oxadiazol-2-yl)propan-1-ones (4a-l)] and triazolo-thiadiazoles[1-(1H-benzo[d]imidazol-2-yl)-3-(6-(substituted)-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-3-yl)propan-1-one (7a-e)] have been synthesized successfully from4-(1H-benzo[d]imidazol-2-yl)-4-oxobutanehydrazide (3) with an aim to produce promising anticancer agents. In vitro anticancer activities of synthesized compounds were screened at the National Cancer Institute (NCI), USA, according to their applied protocol against full NCI 60 human cell lines panel; results showed good to remarkable anticancer activity. Among them, compound (4j, NCS: 761980) exhibited significant growth inhibition and further screened at 10-fold dilutions of five different concentrations (0.01, 0.1, 1, 10 and 100μM) with GI(50) values ranging from 0.49 to 48.0μM and found superior for the non-small cell lung cancer cell lines like HOP-92 (GI(50) 0.49, TGI 19.9,LC(50) >100 and Log(10)GI(50) -6.30, Log(10)TGI -4.70, Log(10)LC(50) >-4.00). 相似文献
154.
Bankapur A Krishnamurthy RS Zachariah E Santhosh C Chougule B Praveen B Valiathan M Mathur D 《PloS one》2012,7(4):e35075
We report here results of a single-cell Raman spectroscopy study of stress effects induced by silver nanoparticles in human mesenchymal stem cells (hMSCs). A high-sensitivity, high-resolution Raman Tweezers set-up has been used to monitor nanoparticle-induced biochemical changes in optically-trapped single cells. Our micro-Raman spectroscopic study reveals that hMSCs treated with silver nanoparticles undergo oxidative stress at doping levels in excess of 2 μg/ml, with results of a statistical analysis of Raman spectra suggesting that the induced stress becomes more dominant at nanoparticle concentration levels above 3 μg/ml. 相似文献
155.
Introduction
Low muscle mass secondary to disease and ageing is an important cause of excess mortality and morbidity. Many studies include a MR brain scan but no peripheral measure of muscle mass. We developed a technique to measure posterior neck muscle cross-sectional area (CSA) on volumetric MR brain scans enabling brain and muscle size to be measured simultaneously.Methods
We performed four studies to develop and test: feasibility, inter-rater reliability, repeatability and external validity. We used T1-weighted MR brain imaging from young and older subjects, obtained on different scanners, and collected mid-thigh MR data.Results
After developing the technique and demonstrating feasibility, we tested it for inter-rater reliability in 40 subjects. Intraclass correlation coefficients (ICC) between raters were 0.99 (95% confidence intervals (CI) 0.98–1.00) for the combined group (trapezius, splenius and semispinalis), 0.92 (CI 0.85–0.96) for obliquus and 0.92 (CI 0.85–0.96) for sternocleidomastoid. The first unrotated principal component explained 72.2% of total neck muscle CSA variance and correlated positively with both right (r = 0.52, p = .001) and left (r = 0.50, p = .002) grip strength. The 14 subjects in the repeatability study had had two MR brain scans on three different scanners. The ICC for between scanner variation for total neck muscle CSA was high at 0.94 (CI 0.86–0.98). The ICCs for within scanner variations were also high, with values of 0.95 (CI 0.86–0.98), 0.97 (CI 0.92–0.99) and 0.96 (CI 0.86–0.99) for the three scanners. The external validity study found a correlation coefficient for total thigh CSA and total neck CSA of 0.88.Discussion
We present a feasible, valid and reliable method for measuring neck muscle CSA on T1-weighted MR brain scans. Larger studies are needed to validate and apply our technique with subjects differing in age, ethnicity and geographical location. 相似文献156.
157.
Abhishek Cukkemane Deepak Nand Sabine Gradmann Markus Weingarth U. Benjamin Kaupp Marc Baldus 《Biomolecular NMR assignments》2012,6(2):225-229
Channels regulated by cyclic nucleotides are key signalling proteins in several biological pathways. The regulatory aspect is conferred by a C-terminal cyclic nucleotide-binding domain (CNBD). We report resonance assignments of the CNBD of a bacterial mlCNG channel obtained using 2D and 3D solid-state NMR under Magic-angle Spinning conditions. A secondary chemical shift analysis of the 141 residue protein suggests a three-dimensional fold seen in earlier X-ray and solution-state NMR work and points to spectroscopic polymorphism for a selected set of resonances. 相似文献
158.
159.
Enrichment of four tandem repeats of guanine (G) rich and cytosine (C) rich sequences in functionally important regions of human genome forebodes the biological implications of four-stranded DNA structures, such as G-quadruplex and i-motif, that can form in these sequences. However, there have been few reports on the intramolecular formation of non-B DNA structures in less than four tandem repeats of G or C rich sequences. Here, using mechanical unfolding at the single-molecule level, electrophoretic mobility shift assay (EMSA), circular dichroism (CD), and ultraviolet (UV) spectroscopy, we report an intramolecularly folded non-B DNA structure in three tandem cytosine rich repeats, 5'-TGTC4ACAC4TGTC4ACA (ILPR-I3), in the human insulin linked polymorphic region (ILPR). The thermal denaturation analyses of the sequences with systematic C to T mutations have suggested that the structure is linchpinned by a stack of hemiprotonated cytosine pairs between two terminal C4 tracts. Mechanical unfolding and Br(2) footprinting experiments on a mixture of the ILPR-I3 and a 5'-C4TGT fragment have further indicated that the structure serves as a building block for intermolecular i-motif formation. The existence of such a conformation under acidic or neutral pH complies with the strand-by-strand folding pathway of ILPR i-motif structures. 相似文献
160.