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131.
132.
Curcumin is a natural compound derived from turmeric and can target malignant tumor molecules involved in cancer propagation. It has potent antioxidant activity, but its effectiveness is limited due to poor absorption and rapid elimination from the body. Various curcumin derivatives have also shown anticancer potential in in-vitro and in-vivo models. Curcumin can target multiple signaling pathways involved in cancer development/progression or induce cancer cell death through apoptosis. In addition, curcumin and its derivatives could also enhance the effectiveness of conventional chemotherapy, radiation therapy and reduce their associated side effects. Lately, nanoparticle-based delivery systems are being developed/explored to overcome the challenges associated with curcumin's delivery, increasing its overall efficacy. The use of an imaging system to track these formulations could also give beneficial information about the bioavailability and distribution of the nano-curcumin complex. In conclusion, curcumin holds significant promise in the fight against cancer, especially in its nanoform, and could provide precise delivery to cancer cells without affecting normal healthy cells.  相似文献   
133.
Glaucoma is the second leading cause of blindness after cataract and is heterogeneous in nature. Employing a genetic approach for the detection of the diseased condition provides an advantage that the gene responsible for the disease can be identified by genetic test. The availability of predictive tests based on the published literature would provide a mechanism for early detection and treatment. The genotype and phenotype information could be a valuable source for predicting the risk of the disease. To this end, a web server has been developed, based on the genotype and phenotype of myocilin mutation, which were identified by familial linkage analysis and case studies. The proposed web server provides clinical data and severity index for a given mutation. The server has several useful options to help clinicians and researchers to identify individuals at a risk of developing the disease. Glaucoma Pred server is available at http://bioserver1.physics.iisc.ac.in/myocilin.  相似文献   
134.
The luciferase reporter phages (LRP) show great promise for diagnostic mycobacteriology. Though conventional constructs developed from lytic phages such as D29 and TM4 are highly specific, they lack sensitivity. We have isolated and characterized Che12, the first true temperate phage infecting M. tuberculosis. Since the tuberculosis (TB) cases among HIV infected population result from the reactivation of latent bacilli, it would be useful to develop LRP that can detect dormant bacteria. During dormancy, pathogenic mycobacteria switch their metabolism involving divergent genes than during normal, active growth phase. Since the promoters of these genes can potentially function during dormancy, they were exploited for the construction of novel mycobacterial luciferase reporter phages. The promoters of hsp60, isocitrate lyase (icl), and alpha crystallin (acr) genes from M. tuberculosis were used for expressing firefly luciferase gene (FFlux) in both Che12 and TM4 phages and their efficiency was evaluated in detecting dormant bacteria from clinical isolates of M. tuberculosis. These LRP constructs exhibited detectable luciferase activity in dormant as well as in actively growing M. tuberculosis. The TM4 ts mutant based constructs showed about one log increase in light output in three of the five tested clinical isolates and in M. tuberculosis H37Rv compared to conventional lytic reporter phage, phAE129. By refining the LRP assay format further, an ideal rapid assay can be designed not only to diagnose active and dormant TB but also to differentiate the species and to find their drug susceptibility pattern.  相似文献   
135.
The seeds of chickpea provide an exceptional source of dietary proteins and is one of the important legumes in both developed and developing countries over the world. The available germplasm of cultivated chickpea is deficient in desired biochemical signatures. To identify new sources of variations for breeding, reduced subsets of germplasm such as mini-core collection can be explored as an effective resource. In the present investigation, mini-core collections consisting of 215 accessions of chickpea were extensively evaluated for tapping biochemical diversity. Analysis included ten biochemical parameters comprising total protein, total free amino acids, phytic acid, tannin, total phenolics, total flavonoids, lectin, DPPH radical scavenging activity, in vitro digestibility of protein and starch. The spectrum of diversity was documented for total protein (4.60–33.90%), total free amino acids (0.092–9.33 mg/g), phytic acid (0.009–4.06 mg/g), tannin (0.232–189.63 mg/g), total phenolics (0.15–0.81 mg/g), total flavonoids (0.04–1.57 mg/g), lectin (0.07–330.32 HU/mg), DPPH radical scavenging activity (26.74–49.11%), in vitro protein digestibility (59.45–76.22%) and in vitro starch digestibility (45.63–298.39 mg of maltose/g). The principal component analysis revealed association of chickpea higher protein content to the lower level of total phenolics and flavonoid contents. The dendrogram obtained by unweighted pair group method using arithmetic average cluster analysis grouped the chickpea accessions into two major clusters. This is the first comprehensive report on biochemical diversity analysed in the mini-core chickpea accessions. The ultimate purpose of conducting such studies was to deliver information on nutritional characteristics for effective breeding programmes. Depending on the objectives of the breeding aforesaid accessions could be employed as a parent.  相似文献   
136.

Background

Idiopathic pulmonary fibrosis exhibits differential progression from the time of diagnosis but the molecular basis for varying progression rates is poorly understood. The aim of the present study was to ascertain whether differential miRNA expression might provide one explanation for rapidly versus slowly progressing forms of IPF.

Methodology and Principal Findings

miRNA and mRNA were isolated from surgical lung biopsies from IPF patients with a clinically documented rapid or slow course of disease over the first year after diagnosis. A quantitative PCR miRNA array containing 88 of the most abundant miRNA in the human genome was used to profile lung biopsies from 9 patients with rapidly progressing IPF, 6 patients with slowly progressing IPF, and 10 normal lung biopsies. Using this approach, 11 miRNA were significantly increased and 36 were significantly decreased in rapid biopsies compared with normal biopsies. Slowly progressive biopsies exhibited 4 significantly increased miRNA and 36 significantly decreased miRNA compared with normal lung. Among the miRNA present in IPF with validated mRNA targets were those with regulatory effects on epithelial-mesenchymal transition (EMT). Five miRNA (miR-302c, miR-423-5p, miR-210, miR-376c, and miR-185) were significantly increased in rapid compared with slow IPF lung biopsies. Additional analyses of rapid biopsies and fibroblasts grown from the same biopsies revealed that the expression of AGO1 and AGO2 (essential components of the miRNA processing RISC complex) were lower compared with either slow or normal lung biopsies and fibroblasts.

Conclusion

These findings suggest that the development and/or clinical progression of IPF might be the consequence of aberrant miRNA processing.  相似文献   
137.
Cellular respiration, mediated by the passive diffusion of oxygen across lipid membranes, is key to many basic cellular processes. In this work, we report the detailed distribution of oxygen across lipid bilayers and examine the thermodynamics of oxygen partitioning via NMR studies of lipids in a small unilamellar vesicle (SUV) morphology. Dissolved oxygen gives rise to paramagnetic chemical shift perturbations and relaxation rate enhancements, both of which report on local oxygen concentration. From SUVs containing the phospholipid sn-2-perdeuterio-1-myristelaidoyl, 2-myristoyl-sn-glycero-3-phosphocholine (MLMPC), an analogue of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), we deduced the complete trans-bilayer oxygen distribution by measuring (13)C paramagnetic chemical shifts perturbations for 18 different sites on MLMPC arising from oxygen at a partial pressure of 30 bar. The overall oxygen solubility at 45 °C spans a factor of 7 between the bulk water (23.7 mM) and the bilayer center (170 mM) and is lowest in the vicinity of the phosphocholine headgroup, suggesting that oxygen diffusion across the glycerol backbone should be the rate-limiting step in diffusion-mediated passive transport of oxygen across the lipid bilayer. Lowering of the temperature from 45 to 25 °C gave rise to a slight decrease of the oxygen solubility within the hydrocarbon interior of the membrane. An analysis of the temperature dependence of the oxygen solubility profile, as measured by (1)H paramagnetic relaxation rate enhancements, reveals that oxygen partitioning into the bilayer is entropically favored (ΔS° = 54 ± 3 J K(-1) mol(-1)) and must overcome an enthalpic barrier (ΔH° = 12.0 ± 0.9 kJ mol(-1)).  相似文献   
138.
We present a suite of software for the complete and easy deposition of NMR data to the PDB and BMRB. This suite uses the CCPN framework and introduces a freely downloadable, graphical desktop application called CcpNmr Entry Completion Interface (ECI) for the secure editing of experimental information and associated datasets through the lifetime of an NMR project. CCPN projects can be created within the CcpNmr Analysis software or by importing existing NMR data files using the CcpNmr FormatConverter. After further data entry and checking with the ECI, the project can then be rapidly deposited to the PDBe using AutoDep, or exported as a complete deposition NMR-STAR file. In full CCPN projects created with ECI, it is straightforward to select chemical shift lists, restraint data sets, structural ensembles and all relevant associated experimental collection details, which all are or will become mandatory when depositing to the PDB. Instructions and download information for the ECI are available from the PDBe web site at http://www.ebi.ac.uk/pdbe/nmr/deposition/eci.html.  相似文献   
139.
The synthesis of an achiral seco-hydroxy-aza-CBI-TMI analog (8) of the duocarmycins is reported. Its specificity for the DNA minor groove of AT-rich sequences and covalent bonding to adenine-N3 was ascertained by a thermal cleavage assay. Compound 8 was found to be cytotoxic in the nanomolar range against murine and human cancer cells. It was further demonstrated that compound 8 was active against murine melanoma (B16-F0) grown in C57BL/6 mice. Compound 8 was also shown to inhibit the growth of the protozoan parasites Leishmania donovani, Leishmania mexicana, Trypanosoma brucei, and Plasmodium falciparum in culture.  相似文献   
140.
Nitric oxide (NO) regulates the vascular tone, and influences survival and apoptosis of endothelial cells (ECs). NO is produced by nitric oxide synthase (NOS) and eNOS is the constitutive enzyme in the endothelium. Though the extracellular matrix (ECM) has been reported to regulate various EC functions, the role of ECM in the regulation of eNOS is not clear. The present study was designed to analyze if laminin‐1 (Ln‐1), the major glycoprotein of the basement membrane, can regulate eNOS. The activity of eNOS was significantly low in ECs maintained on Ln‐1 as compared to those on Col I and polylysine. Reversal of the effect of Ln‐1 on treatment with inhibitor of p38 MAPK and changes in Thr and Ser phosphorylation in purified eNOS suggested that eNOS activity in cells maintained on Ln‐1 is negatively regulated by post‐translational phosphorylation at Ser and Thr residues by recruiting p38 MAPK pathway. Increase in eNOS activity and induction of apoptosis upon inhibition of p38 MAPK and reversal of this on inhibition of NOS by L ‐NAME suggested that increased NO induced apoptosis in ECs maintained on Ln‐1 when p38 MAPK was inhibited. These results suggest that Ln contributes to survival of ECs by negatively modulating eNOS in a p38 MAPK dependent pathway. J. Cell. Physiol. 219: 123–131, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
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