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排序方式: 共有197条查询结果,搜索用时 15 毫秒
101.
In the field of quantitative microscopy, textural information plays a significant role very often in tissue characterization and diagnosis, in addition to morphology and intensity. The aim of this work is to improve the classification accuracy based on textural features for the development of a computer assisted screening of oral sub-mucous fibrosis (OSF). In fact, a systematic approach is introduced in order to grade the histopathological tissue sections into normal, OSF without dysplasia and OSF with dysplasia, which would help the oral onco-pathologists to screen the subjects rapidly. In totality, 71 textural features are extracted from epithelial region of the tissue sections using various wavelet families, Gabor-wavelet, local binary pattern, fractal dimension and Brownian motion curve, followed by preprocessing and segmentation. Wavelet families contribute a common set of 9 features, out of which 8 are significant and other 61 out of 62 obtained from the rest of the extractors are also statistically significant (p < 0.05) in discriminating the three stages. Based on mean distance criteria, the best wavelet family (i.e., biorthogonal3.1 (bior3.1)) is selected for classifier design. support vector machine (SVM) is trained by 146 samples based on 69 textural features and its classification accuracy is computed for each of the combinations of wavelet family and rest of the extractors. Finally, it has been investigated that bior3.1 wavelet coefficients leads to higher accuracy (88.38%) in combination with LBP and Gabor wavelet features through three-fold cross validation. Results are shown and discussed in detail. It is shown that combining more than one texture measure instead of using just one might improve the overall accuracy. 相似文献
102.
Sriram MI Gayathiri S Gnanaselvi U Jenifer PS Mohan Raj S Gurunathan S 《Bioresource technology》2011,102(19):9291-9295
Escherichia fergusonii KLU01, a propitious bacterial strain isolated from oil contaminated soil was identified to be hydrocarbon degrading, heavy metal tolerant and a potent producer of biosurfactant using diesel oil as the sole carbon and energy source. The biosurfactant produced by the strain was characterized to be a lipopeptide. The minimum active dose and critical micelle concentration of the biosurfactant were found as 0.165±0.08 μg and 36 mg/L, respectively. In spite of being an excellent emulsifier, the biosurfactant showed an incredible stability at extremes of temperature, pH and at various concentrations of NaCl, CaCl? and MgCl?. Also the bacterium manifested tolerance towards Manganese, Iron, Lead, Nickel, Copper and Zinc. The strain emerges as a new class of biosurfactant producer with potential environmental and industrial applications, especially in hydrocarbon degradation and heavy metal bioremediation. 相似文献
103.
Shilpa Sharma Sathish Muthu Madhan Jeyaraman Rajni Ranjan Saurabh Kumar Jha 《World journal of stem cells》2021,13(10):1360-1381
With developments in the field of tissue engineering and regenerative medicine, the use of biological products for the treatment of various disorders has come into the limelight among researchers and clinicians. Among all the available biological tissues, research and exploration of adipose tissue have become more robust. Adipose tissue engineering aims to develop by-products and their substitutes for their regenerative and immunomodulatory potential. The use of biodegradable scaffolds along with adipose tissue products has a major role in cellular growth, proliferation, and differentiation. Adipose tissue, apart from being the powerhouse of energy storage, also functions as the largest endocrine organ, with the release of various adipokines. The progenitor cells among the heterogeneous population in the adipose tissue are of paramount importance as they determine the capacity of regeneration of these tissues. The results of adipose-derived stemcell assisted fat grafting to provide numerous growth factors and adipokines that improve vasculogenesis, fat graft integration, and survival within the recipient tissue and promote the regeneration of tissue are promising. Adipose tissue gives rise to various by-products upon processing. This article highlights the significance and the usage of various adipose tissue by-products, their individual characteristics, and their clinical applications. 相似文献
104.
Vino T. Cheriyan Ying Wang Magesh Muthu Shazia Jamal Di Chen Huanjie Yang Lisa A. Polin Adi L. Tarca Harvey I. Pass Q. Ping Dou Sunita Sharma Anil Wali Arun K. Rishi 《PloS one》2014,9(4)
Dithiocarbamate compound Disulfiram (DSF) that binds with copper and functions as an inhibitor of aldehyde dehydrogenase is a Food and Drug Administration approved agent for treatment of alcoholism. Copper complexed DSF (DSF-Cu) also possesses anti-tumor and chemosensitizing properties; however, its molecular mechanisms of action remain unclear. Here we investigated malignant pleural mesothelioma (MPM) suppressive effects of DSF-Cu and the molecular mechanisms involved. DSF-Cu inhibited growth of the murine as well as human MPM cells in part by increasing levels of ubiquitinated proteins. DSF-Cu exposure stimulated apoptosis in MPM cells that involved activation of stress-activated protein kinases (SAPKs) p38 and JNK1/2, caspase-3, and cleavage of poly-(ADP-ribose)-polymerase, as well as increased expression of sulfatase 1 and apoptosis transducing CARP-1/CCAR1 protein. Gene-array based analyses revealed that DSF-Cu suppressed cell growth and metastasis-promoting genes including matrix metallopeptidase 3 and 10. DSF inhibited MPM cell growth and survival by upregulating cell cycle inhibitor p27Kip1, IGFBP7, and inhibitors of NF-κB such as ABIN 1 and 2 and Inhibitory κB (IκB)α and β proteins. DSF-Cu promoted cleavage of vimentin, as well as serine-phosphorylation and lysine-63 linked ubiquitination of podoplanin. Administration of 50 mg/kg DSF-Cu by daily i.p injections inhibited growth of murine MPM cell-derived tumors in vivo. Although podoplanin expression often correlates with metastatic disease and poor prognosis, phosphorylation of serines in cytoplasmic domain of podoplanin has recently been shown to interfere with cellular motility and migration signaling. Post-translational modification of podoplanin and cleavage of vimentin by DSF-Cu underscore a metastasis inhibitory property of this agent and together with our in vivo studies underscore its potential as an anti-MPM agent. 相似文献
105.
106.
Goyal A Muthu K Panneerselvam M Pole AK Ramadas K 《Journal of molecular modeling》2011,17(12):3129-3149
YsxC from Staphylococcus aureus is a member of the GTPase protein family, and is involved in the ribosomal assembly and stability of this microorganism through
its interactions with the L17, S2 and S10 ribosomal proteins. Inhibition of its interactions with L17, S2, S10 and the β′
subunit of RNA polymerase influences ribosomal assembly, which may affect the growth of the microorganism. This makes YsxC
a novel target for the design of inhibitors to treat the disease caused by S. aureus. Understanding the interaction mechanism between YsxC and its partners would aid in the identification of potential catalytic
residues, which could then be targeted to inhibit its function. Accordingly, in the present study, an in silico analysis of
the interactions between YsxC and L17, S2 and S10 was performed, and the potential residues involved in these interactions
were identified. Based on the simulation results, a possible mechanism for the interactions between these proteins was also
proposed. Finally, six ligands from among a library of 81,000 chemical molecules were found to interact with parts of the
G2 and switch II regions of the YsxC protein. Moreover, their interactions with the YsxC protein were observed to provoke
changes at its GTP-binding site, which suggests that the binding of these ligands leads to a reduction in GTPase activity,
and they were also found to affect the interactions of YsxC with its partners. This observation indicates that the proposed
interacting site of YsxC may act as an allosteric site, and disrupting interactions at this site might lead to novel allosteric
inhibition of the YsxC protein. 相似文献
107.
108.
Kazmierczak K Muthu P Huang W Jones M Wang Y Szczesna-Cordary D 《The Biochemical journal》2012,442(1):95-103
FHC (familial hypertrophic cardiomyopathy) is a heritable form of cardiac hypertrophy caused by mutations in genes encoding sarcomeric proteins. The present study focuses on the A13T mutation in the human ventricular myosin RLC (regulatory light chain) that is associated with a rare FHC variant defined by mid-ventricular obstruction and septal hypertrophy. We generated heart-specific Tg (transgenic) mice with ~10% of human A13T-RLC mutant replacing the endogenous mouse cardiac RLC. Histopathological examinations of longitudinal heart sections from Tg-A13T mice showed enlarged interventricular septa and profound fibrotic lesions compared with Tg-WT (wild-type), expressing the human ventricular RLC, or non-Tg mice. Functional studies revealed an abnormal A13T mutation-induced increase in isometric force production, no change in the force-pCa relationship and a decreased Vmax of the acto-myosin ATPase. In addition, a fluorescence-based assay showed a 3-fold lower binding affinity of the recombinant A13T mutant for the RLC-depleted porcine myosin compared with WT-RLC. These results suggest that the A13T mutation triggers a hypertrophic response through changes in cardiac sarcomere organization and myosin cross-bridge function leading to abnormal remodelling of the heart. The significant functional changes observed, despite a low level of A13T mutant incorporation into myofilaments, suggest a 'poison-peptide' mechanism of disease. 相似文献
109.
RE Berry D Muthu TK Shokhireva SA Garrett H Zhang FA Walker 《Chemistry & biodiversity》2012,9(9):1739-1755
The first amino acid of mature native nitrophorin 2 is aspartic acid, and when expressed in E. coli, the wild-type gene of the mature protein retains the methionine-0, which is produced by translation of the start codon. This form of NP2, (M0)NP2, has been found to have different properties from its D1A mutant, for which the Met0 is cleaved by the methionine aminopeptidase of E. coli (R.?E. Berry, T.?K. Shokhireva, I. Filippov, M.?N. Shokhirev, H. Zhang, F.?A. Walker, Biochemistry 2007, 46, 6830). Native N-terminus nitrophorin 2 ((ΔM0)NP2) has been prepared by employing periplasmic expression of NP2 in E. coli using the pelB leader sequence from Erwinia carotovora, which is present in the pET-26b expression plasmid (Novagen). This paper details the similarities and differences between the three different N-terminal forms of nitrophorin 2, (M0)NP2, NP2(D1A), and (ΔM0)NP2. It is found that the NMR spectra of high- and low-spin (ΔM0)NP2 are essentially identical to those of NP2(D1A), but the rate and equilibrium constants for histamine and NO dissociation/association of the two are different. 相似文献
110.
Chung Ill-Min Rajakumar Govindasamy Lee Ji-Hee Kim Seung-Hyun Thiruvengadam Muthu 《Applied microbiology and biotechnology》2017,101(13):5247-5257
Applied Microbiology and Biotechnology - Eclipta prostrata belongs to a family of medicinal plants (Asteraceae) and plays a role in the treatment of several diseases, including infectious... 相似文献