528 research outputs found
MBD genes and hedgehog signalling in cancer
It is accepted that cancer progression is a multi-step process including multiple
genetic and epigenetic events. In this study, two sets of candidate genes in colon and
lung cancer tumourigenesis were studied. The first set comprised members of a
family of genes whose proteins are important in the recognition of the
methylation/epigenetic status of other genes. The second set were members of a
pathway that normally regulate tissue development but whose abnormal, epigenetic
loss of activity could lead to tissue dysregulation and tumourigenesis.
MBD3 and MBD2 are two members of the MBD family of proteins with a methyl-
CpG-binding domain (MBD) involved in transcriptional silencing of methylated
genes. Both genes are located in chromosomal regions that suffer loss of
heterozygosity in colon and lung cancers. By SSCP analysis and methylation
sensitive restriction followed by PCR, 2 mutations were found in 28 cell lines and in
no cases was there evidence of gene silencing by hypermethylation of putative
promoter regions. RT-PCR and northern hybridisation showed expression of MBD3
in all cancer cell lines examined. The results indicate that neither MBD2 nor MBD3
are major targets of genetic and epigenetic alteration in colon and lung cancers.
The Hedgehog (Hh) pathway is a highly conserved signaling cascade involved in
many developmental processes. Mutations in elements of the pathway are associated
with congenital diseases and a number of neoplasms. In this study, two genes of this
pathway, SMO and GLI3 were investigated for expression and epigenetic alterations
in colon and lung cancers. In three cell lines expression of SMO was absent, the
putative SMO promoter was fully methylated and GLI3 was not expressed. Two
other cell lines had a methylated wild-type SMO allele and expressed mutant SMO,and also did not express GLI3. The results indicate that SMO is silenced by CpG
island hypermethylation in colon and lung cancer cell lines, that GLI3 is also
silenced in colon and lung cancer cell lines by an as yet unrevealed mechanism and
that GLI3 is possibly regulated by SMO in a manner outside the normal sequence of
steps currently thought to comprise the Hh pathway
Observation of dressed intra-cavity dark states
Cavity electromagnetically induced transparency in a coherently prepared
cavity-atom system is manifested as a narrow transmission peak of a weak probe
laser coupled into the cavity mode. We show that with a resonant pump laser
coupling the cavity-confined four-level atoms from free space, the narrow
transmission peak of the cavity EIT is split into two peaks. The two peaks
represent the dressed intra-cavity dark states and have a frequency separation
approximately equal to the Rabi frequency of the free-space pump laser. We
observed experimentally the dressed intra-cavity dark states in cold Rb atoms
confined in a cavity and the experimental results agree with theoretical
calculations based on a semiclassical analysis.Comment: 10 pages, 6 figure
Variation of Oriental Oak (Quercus variabilis) Leaf δ13C across Temperate and Subtropical China: Spatial Patterns and Sensitivity to Precipitation
The concentration of the carbon-13 isotope (leaf δ13C) in leaves is negatively correlated with the mean annual precipitation (MAP) atlarge geographical scales. In this paper, we explain the spatial pattern of leaf δ13C variation for deciduous oriental oak (Quercus variabilis Bl.) across temperate and subtropical biomes and its sensitivity to climate factors such as MAP. There was a 6Ⱐvariation in the leaf δ13C values of oak with a significant positive correlation with latitude and negative correlations with the mean annual temperature (MAT) and MAP. There was no correlation between leaf δ13C and altitude or longitude. Stepwise multiple regression analyses showed that leaf δ13C decreased 0.3Ⱐper 100 mm increase in MAP. MAP alone could account for 68% of the observed variation in leaf δ13C. These results can be used to improve predictions for plant responses to climate change and particularly lower rainfall
Characterization, dissolution and solubility of the hydroxypyromorphiteâhydroxyapatite solid solution [(PbxCa1âx)5(PO4)3OH] at 25 °C and pH 2â9
Additional file 1: Appendix A. Supplementary dataâX-ray diffractograms (XRD) of the hydroxypyromorphiteâhydroxyapatite solid solution [(PbxCa1âx)5(PO4)3(OH)] after dissolution at 25âËC and an initial pH of 5.60 and 9.00 for 300d
Combined Detection of Mean Platelet Volume and Immunoglobins as a Strategy for the Diagnosis of Systemic Lupus Erythematosus
Objective:To explore the possibility of diagnosing and monitoring patients with systemic lupus erythematosus (SLE) using the combination of mean platelet volume (MPV) and routine immunoglobulin test. Method:116 patients with SLE were divided into 3 groups according to their clinical characteristics, including 29 patients with renal impairment, 44 cases of active stage and 43 cases of inactive patients. 40 healthy subjects were randomly selected as controls. Subjects were tested for routine blood test and plasma Immunoglobins, such as IgG, IgA, IgM, C3, C4, CH50, CRP. The results were analyzed and the characteristics of each group of subjects were determined, the correlation between test results and diagnosis were studied. Result: In comparison to the control group, the serum level of MPV, C3 and C4 were decreased (P<0.05), and C reactive protein level was elevated (P<0.001) in the three groups of SLE patients. The IgG level in active and inactive SLE patients was increased (P<0.0001), CH50 level was decreased in patients with inactive SLE (P<0.05), IgA level of active SLE subjects was found to be elevated (P<0.05), IgM in patients with renal impairment was decreased (P<0.05). Other than that, no other significant characteristic were found. Conclusion: The pathogenesis of SLE is a complex process involving multiple factors. The changes of MPV, IgG, IgA, IgM, C3, C4, CH50 and CRP in SLE patients are characteristic parameters. The combination of the above indicators can help to determine the diagnosis and staging of SLE. The timely diagnosis and treatment of SLE patients has important clinical significance in protecting the organ function of SLE patients and improving the prognosis
Coherent manipulation of quantum states in a coupled cavity-atom system
We study atomic coherence and interference in four-level atoms confined in an optical cavity and explores the interplay between cavity QED and electromagnetically induced transparency (EIT). The destructive interference can be induced in the coupled cavityatom system with a free-space control laser tuned to the normal mode resonance and leads to suppression of the normal mode excitation. Then by adding a pump laser coupled to the four-level atoms from free space, the control-laser induced destructive interference can be reversed and the normal mode excitation is restored. When the free-space control laser is tuned to the atomic resonance and forms a Î-type EIT configuration with the cavity-atom system, EIT is manifested as a narrow transmission peak of a weak probe laser coupled into the cavity mode. With the free-space pump laser driving the cavity-confined atoms in a four-level configuration, the narrow transmission peak of the cavity EIT can be split into two peaks and the dressed intra-cavity dark states are created analogous to the dressed states in free space. We report experimental studies of such coherently coupled cavityatom system realized with cold Rb atoms confined in an optical cavity and discuss possible applications in quantum nonlinear optics and quantum information science
In Vitro Antibacterial Activity of Galla Chinensis Combined with Different Antibacterial Drugs against Carbapenem-Resistant E.Coli
Objective: To evaluate the antibacterial effects of meropenem and levofloxacin respectively combined with Galla chinensis on carbapenem-resistant Escherichia coli in vitro. MethodsďźÂ The protocol was designed with checkerboard method and the carbapenem-resistant E.coli was isolated in our hospital. The minimum inhibitory concentrations(MICs) of G. chinensis alone and combined with 2 antimicrobial agents against carbapenem-resistant E.coli were determined by broth dilution method and the fractional inhibitory concentration index (FICI) was calculated according to MICs results. ResultďźÂ the combined use of G. chinensis and meropenem (or levofloxacin) significantly decreased both MIC50 and MIC90; After the combination of G. chinensis and meropenem, the synergistic effect was 86.7%, and the additive effect was 13.3%, no irrelevant and antagonistic effects. After combined use of G. chinensis and levofloxacin, the synergistic effect was 66.7%, and the additive effect was 33.3%. No irrelevant and antagonistic effects. ConclusionďźÂ Galla chinensis combined with meropenem or levofloxacin has synergistic and additive antibacterial effect, with certain combined antibacterial activity
Hydrothermal Synthesis of Ln(OH) 3
One-dimensional rare earth oxides and hydroxides are of importance in many applications due to their rich physicochemical properties. In this work, we synthesized Ln(OH)3 (Lnâ=âEu, Nd, Dy) nanorods by a hydrothermal method with the assistance of n-butylamine as an alkaline resource. The porous Ln2O3 nanorods were produced through annealing the corresponding Ln(OH)3 nanorods. XRD and TEM techniques were employed to characterize the products. The annealing process and the optical properties of as-synthesized Ln2O3 are also investigated by TG and PL test. We expected that these nanomaterials could find potential applications in the future
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