Mechanism

Source: www.ncbi.nlm.nih.gov --- 9 days ago
Related Articles [Mechanism of onset and aggravation of acute pancreatitis] Nippon Shokakibyo Gakkai Zasshi. 2008 Aug;105(8):1157-65 Authors: Kihara Y, Otsuki M PMID: 18678990 [PubMed - indexed for MEDLINE] ...

Source: www.ncbi.nlm.nih.gov --- 9 days ago
Related Articles A bicistronic CYCLIN D1-TROP2 mRNA chimera demonstrates a novel oncogenic Mechanism in human cancer. Cancer Res. 2008 Oct 1;68(19):8113-21 Authors: Guerra E, Trerotola M, Dell' Arciprete R, Bonasera V, Palombo B, El-Sewedy T, Ciccimarra T, Crescenzi C, Lorenzini F, Rossi C, Vacca G, Lattanzio R, Piantelli M, Alberti S A chimeric CYCLIN D1-TROP2 mRNA was isolated from human ovarian and mammary cancer cells. The CYCLIN D1-TROP2 mRNA was shown to be a potent oncogene as it transforms naïve, primary cells in vitro and induces aggressive tumor growth in vivo in cooperation with activated RAS. Silencing of the chimeric mRNA inhibits the growth of breast cancer cells. The CYCLIN D1-TROP2 mRNA was expressed by a large fraction of the human gastrointestinal, ovarian, and endometrial tumors analyzed. It is most frequently detected in intestinal cell aneuploid cancers and it is coexpressed with activated RAS oncogenes, consistent with a cooperative transforming activity in human cancers. The chimeric mRNA is a bicistronic transcript of post transcriptional origin that independently translates the Cyclin D1 and Trop-2 proteins. This is a novel Mechanism of CYCLIN D1 activation that achieves the truncation of the CYCLIN D1 mRNA in the absence of chromosomal rearrangements. This leads to a higher CYCLIN D1 mRNA stability, with inappropriate expression during the cell cycle. The stabilized CYCLIN D1 mRNA cooperates with TROP2 in sti ...

Source: www.ncbi.nlm.nih.gov --- 7 days ago
Related Articles Bidirectional ventricular tachycardia caused by a reentrant Mechanism with left bundle branch block configuration on electrocardiography. Circ J. 2008 Aug;72(8):1373-7 Authors: Ueda-Tatsumoto A, Sakurada H, Nishizaki M, Okazaki H, Komiyama K, Mizusawa Y, Tejima T, Hiraoka M Reentrant bidirectional ventricular tachycardia (VT) with left bundle branch block (LBBB) configuration was diagnosed in a 54-year-old woman who showed 2 types of VT: QRS morphologies of LBBB with inferior axis and LBBB with superior axis. The development of VT with a superior axis was preceded by VT with inferior axis and/or both configurations of VT in alternate beats exhibiting bidirectional VT. The electrophysiological study demonstrated reproducible induction of both types of VT by programmed ventricular stimulation and both types of VT were entrained. Using conventional pace mapping and electro-anatomical mapping methods, radiofrequency energy applications at the 2 exit sites of the reentry path successfully terminated both types of VT and the patient was free from VT attacks for more than 15 months. PMID: 18654028 [PubMed - indexed for MEDLINE] ...

Source: www.ncbi.nlm.nih.gov --- 7 days ago
Related Articles Aberrant DNA methylation is a dominant Mechanism in MDS progression to AML. Blood. 2008 Oct 2; Authors: Jiang Y, Dunbar A, Gondek LP, Mohan S, Rataul M, O'Keefe C, Saunthararajah Y, Maciejewski JP Myelodysplastic syndromes (MDS) are clonal hematological disorders that frequently represent an intermediate disease stage before progression to acute myeloid leukemia (AML). As such, study of MDS/AML can provide insight into the mechanisms of neoplastic evolution. In 184 MDS and AML patients, DNA methylation microarray and high-density SNP-A karyotyping were used to assess the relative contributions of aberrant DNA methylation and chromosomal deletions to tumor-suppressor gene (TSG) silencing during disease progression. Aberrant methylation was seen in every sample, on average affecting 91/1505 CpG loci in early MDS and 179/1505 loci after blast transformation (RAEB/AML). In contrast, chromosome aberrations were seen in 79% of early MDS samples, 90% of RAEB/AML samples, and were not as widely distributed over the genome. Analysis of the most frequently aberrantly methylated genes identified FZD9 as a candidate TSG on chromosome 7. In patients with chromosome deletion at the FZD9 locus, aberrant methylation of the remaining allele was associated with the poorest clinical outcome. These results indicate that aberrant methylation can cooperate with chromosome deletions to silence TSG. However, the ubiquity, extent and correlat ...

Source: www.ncbi.nlm.nih.gov --- 10 days ago
Related Articles [Advances in the study of molecular Mechanism of APOBEC3G anti-HIV-1] Yao Xue Xue Bao. 2008 Jul;43(7):678-82 Authors: Fan B, Cen S, Jiang JD Apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3 protein G (APOBEC3G) is part of the innate immune system of host cells and has cytidine deaminase activity. It specifically incorporates into the virion during HIV-1 replication. The incorporation of APOBEC3G needs its interaction with HIV-1 Gag. In the HIV-1 reverse transcription process, APOBEC3G deaminates dC to dU in the first minus strand cDNA, and then induces extensive hypermutation in the viral genome. Besides deamination, APOBEC3G also inhibits HIV-1 by some kinds of non-deamination mechanisms which need to be further elucidated. HIV-1 Vif counteracts the activity of APOBEC3G by an ubiquitin-proteasome-mediated degradation of APOBEC3G. As a broad spectrum inhibitor of viruses, APOBEC3G also inhibits various retroviruses, retrotransposons and other viruses like HBV. Upregulating the expression of APOBEC3G or blocking the Vif-mediated degradation of APOBEC3G might be novel strategies to treat HIV-1 infection in the future. PMID: 18819469 [PubMed - in process] ...

Source: www.ncbi.nlm.nih.gov --- 7 days ago
Related Articles Mechanism of action of ZOT-derived peptide AT-1002, a tight junction regulator and absorption enhancer. Int J Pharm. 2008 Sep 11; Authors: Gopalakrishnan S, Pandey N, Tamiz AP, Vere J, Carrasco R, Somerville R, Tripathi A, Ginski M, Paterson BM, Alkan SS Tight junctions (TJs) are intercellular structures that control paracellular permeability and epithelial polarity. It is now accepted that TJs are highly dynamic structures that are regulated in response to exogenous and endogenous stimuli. Here, we provide details on the Mechanism of action of AT-1002, the active domain of Vibrio cholerae's second toxin, zonula occludens toxin (ZOT). AT-1002, a hexamer peptide, caused the redistribution of ZO-1 away from cell junctions as seen by fluorescence microscopy. AT-1002 also activated src and mitogen activated protein (MAP) kinase pathways, increased ZO-1 tyrosine phosphorylation, and rearrangement of actin filaments. Functionally, AT-1002 caused a reversible reduction in transepithelial electrical resistance (TEER) and an increase in lucifer yellow permeability in Caco-2 cell monolayers. In vivo, co-administration of salmon calcitonin with 1mg of AT-1002 resulted in a 5.2-fold increase in AUC over the control group. Our findings provide a mechanistic explanation for AT-1002-induced tight junction disassembly, and demonstrate that AT-1002 can be used for delivery of other agents in vivo. PMID: 18832018 [PubMed - as supplied ...

Source: www.ncbi.nlm.nih.gov --- 8 days ago
Related Articles Increased oxidative stress as a Mechanism for decreased BDNF levels in acute manic episodes. Rev Bras Psiquiatr. 2008 Sep;30(3):243-245 Authors: Kapczinski F, Frey BN, Andreazza AC, Kauer-Sant'anna M, Cunha AB, Post RM OBJECTIVE AND METHOD: There is a growing amount of data indicating that alterations in brain-derived neurotrophic factor and increased oxidative stress may play a role in the pathophysiology of bipolar disorder. In light of recent evidence demonstrating that brain-derived neurotrophic factor levels are decreased in situations of increased oxidative stress, we have examined the correlation between serum thiobarbituric acid reactive substances, a measure of lipid peroxidation, and serum brain-derived neurotrophic factor levels in bipolar disorder patients during acute mania and in healthy controls. RESULTS: Serum thiobarbituric acid reactive substances and brain-derived neurotrophic factor levels were negatively correlated in bipolar disorder patients (r = -0.56; p = 0.001), whereas no significant correlation was observed in the control group.. CONCLUSION: These results suggest that alterations in oxidative status may be mechanistically associated with abnormal low levels of brain-derived neurotrophic factor observed in individuals with bipolar disorder. PMID: 18833425 [PubMed - as supplied by publisher] ...

Source: www.ncbi.nlm.nih.gov --- 8 days ago
Related Articles Endocochlear potential depends on Cl(-) channels: Mechanism underlying deafness in Bartter syndrome IV. EMBO J. 2008 Oct 2; Authors: Rickheit G, Maier H, Strenzke N, Andreescu CE, De Zeeuw CI, Muenscher A, Zdebik AA, Jentsch TJ Human Bartter syndrome IV is an autosomal recessive disorder characterized by congenital deafness and severe renal salt and fluid loss. It is caused by mutations in BSND, which encodes barttin, a beta-subunit of ClC-Ka and ClC-Kb chloride channels. Inner-ear-specific disruption of Bsnd in mice now reveals that the positive potential, but not the high potassium concentration, of the scala media depends on the presence of these channels in the epithelium of the stria vascularis. The reduced driving force for K(+)-entry through mechanosensitive channels into sensory hair cells entails a profound congenital hearing loss and subtle vestibular symptoms. Although retaining all cell types and intact tight junctions, the thickness of the stria is reduced early on. Cochlear outer hair cells degenerate over several months. A collapse of endolymphatic space was seen when mice had additionally renal salt and fluid loss due to partial barttin deletion in the kidney. Bsnd(-/-) mice thus demonstrate a novel function of Cl(-) channels in generating the endocochlear potential and reveal the Mechanism leading to deafness in human Bartter syndrome IV. PMID: 18833191 [PubMed - as supplied by publisher] ...

Source: www.ncbi.nlm.nih.gov --- 8 hours ago
Related Articles [Degradation Mechanism and efficiency of organic pollutants of landfill leachate in different redox zones] Huan Jing Ke Xue. 2007 Sep;28(9):2041-5 Authors: Dong J, Zhao YS, Zhang WH, Zhao XB, Liu YY, Han R A soil column filled with sandy soil was constructed to investigate degradation Mechanism and efficiency of organic landfill leachate pollutants in subsurface environment. Experimental results indicated that iron reduction zone may be play an important role on degradation of organics, and its efficiency was up to 86.24% averagely, reduction zone for nitrate, sulfate and methanogenic followed, and that was 75.93%, 79.81%, 74.02% and 65.09% averaged, respectively. Anaerobic reducing environment could have played an important role on degradation of benzoxazole, antipyrine, indene, etc. naphthalene, cyclohexanone and part of cyclo-alkyl hydrocarbon, etc. Which were difficult to biodegrade. Maximum degradation efficiency of pollutants was different in different redox zones. For instance, in sulfate reduction zone, the highest degradation efficiency of 1, 1, 1-trichloroethane and 1, 2-dimethylbenzene was 80% and 71.43%, respectively. The highest degradation efficiencies of TCE and MTBE were in nitrate reduction zone, and reached 81.25% and 92.58%. respectively; Benzene was degraded completely in sulfate reduction zone and iron reduction zone. PMID: 17990554 [PubMed - indexed for MEDLINE] ...

Source: www.ncbi.nlm.nih.gov --- 8 days ago
Related Articles Structural determinants for alpha-neurotoxin sensitivity in muscle nAChR and their implications for the gating Mechanism. Channels (Austin). 2007 Jul-Aug;1(4):234-7 Authors: Dellisanti CD, Yao Y, Stroud JC, Wang ZZ, Chen L Neurotoxins from snake venoms act as potent antagonists on the nicotinic acetylcholine receptors (nAChRs). Alpha-neurotoxins such as alpha-bungarotoxin (alpha-Btx) selectively bind to the skeletal muscle nAChRs among other subtypes, causing failure of the neuromuscular transmission. Through evolution, some species including snakes and mongoose have developed resistance to alpha-neurotoxins via specific amino acid substitutions in their muscle-type nAChR alpha1 subunit, which constitutes most of the toxin-binding site. Here we analyze these sequence variations in the context of our recent crystal structure of the extracellular domain of the mouse nAChR alpha1 bound to alpha-Btx. Our structure suggests that alpha-Btx has evolved as an extremely potent antagonist of muscle nAChR by binding the receptor tightly, blocking its ligand site, and locking its conformation in a closed state. Conversely, most toxin-resistant mutations occur at the alpha-Btx binding interface on nAChR alpha1 but away from the agonist binding site. These mutations can interfere with the binding of alpha-Btx without having deleterious effect on the gating function. These analyses not only help understand the structural determinants ...

Source: www.nature.com --- 5 days ago
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Source: pubs.acs.org --- 3 days ago
Beáta G Vértessy and Judit Tóth Web Release Date: Tue, 7 Oct 2008 00:00:00 EDT (Article) DOI: 10.1021/ar800114w ...

Source: www.thehindu.com --- 6 hours ago
To meet Narayanan, Menon ...

Source: pubs.acs.org --- 9 days ago
Carlo Sbraccia, Federico Zipoli, Roberto Car, Morrel H. Cohen, G. Charles Dismukes, and Annabella Selloni Web Release Date: Wed, 1 Oct 2008 00:00:00 EDT (Article) DOI: 10.1021/jp803657b ...

Source: seekingalpha.com --- 5 days ago
David Enke submits: The Financial Services Authority [FSA] in the UK is planning to conduct a " significant reappraisal " on how banks use securitization to free-up capital (see Financial Times article ) given that mortgage bonds and other asset-backed securities are becoming more complicated than originally believed. This is important for US investors given that the FSA is the leading voice on the Basel Committee. Adjustment beyond current Basel II regulations and guidelines are already being discussed with regard to raising bank capital requirements. Complete Story » ...

Source: stacks.iop.org --- 21 hours ago
Author(s): Shinta Kasuya, Masahiro Kawasaki and Fuminobu Takahashi Affiliation(s): Department of Information Science, Kanagawa University, Kanagawa 259-1293, Japan; Institute for Cosmic Ray Research, University of Tokyo, Chiba 277-8582, Japan; Institute for the Physics and Mathematics of the Universe, University of Tokyo, Chiba 277-8582, Japan ...

Source: www.timesofmalta.com --- 4 days ago
The Budgets Committee of the European Parliament today adopted an amendment tabled last month by MEP Simon Busuttil calling for the establishment of a "Solidarity Mechanism" to enable burden-sharing on immigration among EU member states. The... ...