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Background Helicobacter pylori is a bacterium that affects about 50% of the world population and, despite being often asymptomatic, it is responsible of several gastric diseases, from gastritis to gastric cancer. The protein Lpp20 (HP1456) plays an important role in bacterium survival and host colonization, but the possibility that it might be involved in the etiology of H. pylori -related disorders is an unexplored issue. Lpp20 is a lipoprotein bound to the external membrane of the bacterium, but it is also secreted inside vesicles along with other two proteins of the same operon, i.e. HP1454 and HP1457. Results In this study we determined the crystal structure of Lpp20 and we found that it has a fold similar to a carcinogenic factor released by H. pylor i, namely Tipα. We demonstrate that Lpp20 promotes cell migration and E-cadherin down-regulation in gastric cancer cells, two events recalling the epithelial–mesenchymal transition (EMT) process. Differently from Tipα, Lpp20 also stimulates cell proliferation. Conclusions This identifies Lpp20 as a new pathogenic factor produced by H. pylori that promotes EMT and thereby the progression of cancer to the metastatic state. [ABSTRACT FROM AUTHOR]

[Display omitted] In this Letter we describe structure–activity relationship (SAR) studies conducted in five distinct regions of a new 2-amino- N -phenylacetamides series of Slack potassium channel inhibitors exemplified by recently disclosed high-throughput screening (HTS) hit VU0606170 (4). New analogs were screened in a thallium (Tl+) flux assay in HEK-293 cells stably expressing wild-type human (WT) Slack. Selected analogs were screened in Tl+ flux versus A934T Slack and other Slo family members Slick and Maxi-K and evaluated in whole-cell electrophysiology (EP) assays using an automated patch clamp system. Results revealed the series to have flat SAR with significant structural modifications resulting in a loss of Slack activity. More minor changes led to compounds with Slack activity and Slo family selectivity similar to the HTS hit. [ABSTRACT FROM AUTHOR]

This paper presents a neuro fuzzy clustering algorithm, Fuzzy Kohonen Local Information C-Means (FKLICM), for classification of remote sensing images. The proposed algorithm is a hybridization of the conventional Kohonen clustering network and Fuzzy Local Information C-Means (FLICM) to produce a much more efficient and accurate clustering algorithm. The proposed algorithm first forms a fused image with three Multispectral bands and pan band of Landsat 7 Enhanced Thematic Mapper Plus (ETM+) using the Brovey transform. The fused image is a three band image with higher resolution and better visual perception. The fused image is reduced to a one-dimensional image using principal component analysis (PCA). The FKLICM algorithm is applied on the PC-1 image to classify the remote sensing image into different land cover types. Integrating the neural network with a fuzzy system combines the advantages and overcomes the limitations of both technologies. The experimental results of the proposed algorithm are compared with two other algorithms, FCM and GIFP-FCM. The classification results and accuracy assessment show that FKLICM yields better results than the other methods. [ABSTRACT FROM AUTHOR]

A mild and efficient iodine-mediated intramolecular heteroannulation approach for the construction of the imidazo[1,2- a]pyrazinone core has been developed. Under ambient conditions, this metal-free protocol allows easy access to densely functionalized imidazo[1,2- a]pyrazinone-3-carbaldehydes or (aminomethyl)imidazo[1,2- a]pyrazinones from substrates containing terminal alkynes by cyclization and subsequent oxidation or amination. Further diversification may be introduced by using substrates containing an internal alkyne and/or Suzuki coupling after cyclization to generate polysubstituted (dihydro)imidazo[1,2- a]pyrazinones. [ABSTRACT FROM AUTHOR]

Abstract: An efficient base-promoted 3-alkylation of 3,5-dichloro-2(1H)-pyrazinones with various malonate esters is described. The method constitutes a simple example of a C–C bond forming process at the 3-position of the pyrazinone core allowing to attain 3-substituted pyrazinones in good to high yields. 3-Alkylation of 3,5-dichloro-2(1H)-pyrazinones with acetoacetic ester was accompanied by further retro-Claisen fragmentation. [Copyright &y& Elsevier]

Background: Although NGLY1 is known as a pivotal enzyme that catalyses the deglycosylation of denatured glycoproteins, information regarding the responses of human cancer and normal cells to NGLY1 suppression is limited.Methods: We examined how NGLY1 expression affects viability, tumour growth, and responses to therapeutic agents in melanoma cells and an animal model. Molecular mechanisms contributing to NGLY1 suppression-induced anticancer responses were revealed by systems biology and chemical biology studies. Using computational and medicinal chemistry-assisted approaches, we established novel NGLY1-inhibitory small molecules.Results: Compared with normal cells, NGLY1 was upregulated in melanoma cell lines and patient tumours. NGLY1 knockdown caused melanoma cell death and tumour growth retardation. Targeting NGLY1 induced pleiotropic responses, predominantly stress signalling-associated apoptosis and cytokine surges, which synergise with the anti-melanoma activity of chemotherapy and targeted therapy agents. Pharmacological and molecular biology tools that inactivate NGLY1 elicited highly similar responses in melanoma cells. Unlike normal cells, melanoma cells presented distinct responses and high vulnerability to NGLY1 suppression.Conclusion: Our work demonstrated the significance of NGLY1 in melanoma cells, provided mechanistic insights into how NGLY1 inactivation leads to eradication of melanoma with limited impact on normal cells, and suggested that targeting NGLY1 represents a novel anti-melanoma strategy. [ABSTRACT FROM AUTHOR]

Acta Obstet Gynecol Scand 2003; 82: 89–90. © Acta Obstet Gynecol Scand 2003. [ABSTRACT FROM AUTHOR]

This is an efficient and mild method for the synthesis of the title compounds. [ABSTRACT FROM AUTHOR]

A base-promoted 3-alkylation of title compounds (I) with malonate esters (II) affording the corresponding 3-alkylated derivatives (III) is described. [ABSTRACT FROM AUTHOR]

Mono- as well as dipropargylic amines were synthesized using α-amino esters as inexpensive building blocks under a single catalytic system (copper bromide, 100 °C, 4 h, toluene) where the reactant ratio ( 1a/ 2a/ 3a) acted as product specific switch. Both secondary (mono) as well as tertiary (di) propargylic amines formed via three- and five-component coupling exhibited wide substrate scope with moderate to good yields and satisfactory diastereoselectivity in a few cases. The practical utility of the method is enhanced by providing a facile access to enantiopure propargylic amines via lipase-catalyzed resolution along with synthesis of unsymmetrical dipropargylic amines, secondary propargylic amines bearing quaternary carbon centers and imidazolidin-2-ones. [ABSTRACT FROM AUTHOR]

Light-weight flexible arms will most likely constitute the next generation robots due to their large payload carrying capacities at high speeds and less power demand. Control problem of robots with flexible members is more complex compared to rigid robots due to vibrations during the motion. This paper presents the optimization technique inspired by social behavior of bird flocking to optimize hybrid Fuzzy Precompensated Proportional – Derivative (PD) controller in trajectory control of two link rigid-flexible manipulator. Numerical simulation using the dynamic model of two link rigid-flexible manipulator shows the effectiveness of the approach in trajectory tracking problems and the use of fuzzy precompensation has superior performance in terms of improvement in transient and steady state response, robustness to variations in loading conditions and ease to use in practice. Comparative evaluation with respect to genetic algorithm based optimization is presented to validate the controller design. The results presented emphasize that a satisfactory tracking precision could be achieved using hybrid Fuzzy Precompensated Proportional – Derivative controller with particle swarm optimization. [ABSTRACT FROM AUTHOR]

Accelerator mass spectrometry (AMS) is commonly used to determine the abundance ratios of long-lived isotopes such as 10B, 14C, 36Cl, 129I, etc. to their stable counterparts at levels as low as 10−16. Secondary ion mass spectrometry (SIMS) is routinely used to determine impurity levels in materials by depth profiling techniques. Trace-element accelerator mass spectrometry (TEAMS) is a combination of AMS and SIMS, presently being used at the University of North Texas, for high-sensitivity (ppb) impurity analyses of stable isotopes in semiconductor materials. The molecular break-up characteristics of AMS are used with TEAMS to remove the molecular interferences present in SIMS. Measurements made with different substrate/impurity combinations demonstrate that TEAMS has higher sensitivity for many elements than other techniques such as SIMS and can assist with materials characterization issues. For example, measurements of implanted As in the presence of Ge in GexSi1−x/Si is difficult with SIMS because of molecular interferences from 74GeH, 29Si30Si16O, etc. With TEAMS, the molecular interferences are removed and higher sensitivities are obtained. Measured substrates include Si, SiGe, CoSi2, GaAs and GaN. Measured impurities include B, N, F, Mg, P, Cl, Cr, Fe, Ni, Co, Cu, Zn, Ge, As, Se, Mo, Sn and Sb. A number of measurements will be presented to illustrate the range and power of TEAMS. [Copyright &y& Elsevier]

A simple protocol for the synthesis of mono-propargylic amines (IV), (VI), (VIII), (XI), and (XIV) as well as symmetrical dipropargylic amines (XV) from α-amino esters, aldehydes or ketones, and alkynes. [ABSTRACT FROM AUTHOR]

This report described two cases of nasal glial heterotopia which primarily presented as nasal polyp. Glial heterotopia one form of congenital midline nasal mass is a rare anomaly usually detected at birth. There are congenital malformation of displaced normal, mature glial tissue, which is no longer in continuity with an intracranial component. The case reports correlates clinical findings with immunohistochemical investigations. [ABSTRACT FROM AUTHOR]

The success with occlusion devices for the closure of atrial septal defects and patent ductus arteriosus prompted the transcatheter closure of single and multiple muscular ventricular septal defects (VSD). The procedure for VSD was first attempted by Lock et al. in 1988 and devices originally designed for the closure of other intracardiac defects (Rashkind umbrella device, Lock clamshell, Cardioseal, coils, Sideris buttoned device etc.) were used with a variable success rate and a residual shunt. Recently, specially designed Amplatzer muscular VSD occluder and Sideris device are in use. The Amplatzer muscular VSD occluder has been undergoing clinical trial since 1998 after the animal experiments had shown 100% occlusion and complete endothelization at 3 months. The procedure was first attempted in August 1995 using the Rashkind umbrella device and since April 1998 only the Amplatzer muscular VSD occluder has been used. Of the 149 patients who underwent transcatheter closure of VSD, 50 had muscular trabecular defects in various locations: mid-muscular, anterior, posterior, or apical. All cases were selected by detailed transthoracic and/or transesophageal echocardiography (TTE) and aneurysm of the muscular septum was observed in three of them. The age range was 3-28 years and the diameter of VSD was 4-11 mm. In all but one patient, the device was deployed from the venous side. Simultaneous TTE was done for proper positioning of the device and continuous electrocardiographic monitoring was also done for any arrhythmia/conduction defects. All patients were followed up every 3 months and received 3-5 mg/kg aspirin for 6 months. The procedure was successful in all patients. The Rashkind umbrella device (17 mm) was used in two and Amplatzer muscular VSD occluder (6-14 mm) in 48 patients. Forty-four devices were delivered by antegrade transvenous approach and six by the transjugular route. None had residual shunt, newaortic regurgitation, or tricuspid regurgitation. Transient complete heart block after 24 hours was noticed in one patient. On a follow-up of 2-90 months, the device was in position in all patients. There was no embolization of the device, and no late-conduction defects, infective endocarditis, or hemolysis. Transcatheter closure of muscular VSD is safe and efficacious, and should be considered as a procedure of choice as an alternative to surgery that avoids cardiopulmonary bypass. [ABSTRACT FROM AUTHOR]

A new ion beam analysis-based, single ion technique called the time to first photon has been developed to measure the decay of the luminescence signal of phosphors. Such measurements are currently needed to study luminescence decay mechanisms following high-density excitations and to identify strongly luminescent phosphor coatings with short lifetimes for ion photon emission microscopy (IPEM). The samples for this technique consist of thin phosphor layers placed or coated on the surface of PIN diodes. Single ions from an accelerator strike this sample and simultaneously create ion beam induced luminescence (IBIL) from the phosphor that is measured by a single-photon-detector, and an ion beam induced charge collection (IBICC) signal in the PIN diode. In this case, the IBICC signal provides the start pulse and the IBIL signal the stop pulse to a time to amplitude converter. It is straightforward to show that this approach also measures a signal proportional to activity versus time with an accuracy of 5% as long as the number of detected photons per ion is less than 0.1, which usually requires the use of absorbers for the IBIL detector or electronic discrimination for the IBIL signals. Details of the new analysis are given together with examples of luminescence decay measurements of several ceramic phosphors being considered to coat IPEM samples. IPEM is currently being developed at Sandia National Laboratory (SNL), the University of North Texas in Denton, and the Universities and INFN of Padova and Torino. [Copyright &y& Elsevier]

A 55 yr. old woman attended emergency with acute intestinal obstruction ..The patient underwent emergency surgical procedure of intestinal resection after straight X-ray,few haematological and biochemical investigations. On gross examination ileal stricture due to mass in ileocaecal region with mesenteric lymph nodes found which on histological examination came out to be a squamous cell carcinoma with metastatic deposit in lymph node.The patient had a hysterectomy done 3&1/2 years back for Stage IIB squamous cell carcinoma of cervix for which she received chemoradiation.The intestinal obstruction very likely to be a metastatic presentation. [ABSTRACT FROM AUTHOR]

Various devices can be realized on strained GeSi/Si substrates by doping the substrate with different impurities such as As. As is an n-type dopant in both Ge and Si. As cross contamination can also arise during germanium preamorphization implantation due to inadequate mass resolution in the implanter. Thus, it is important to be able to accurately measure low-level As concentrations in the presence of Ge. Secondary ion mass spectrometry (SIMS) is the standard technique for these types of measurements but is constrained by mass interferences from molecular ions ([sup 74]GeH, [sup 29]Si[sup 30]Si[sup 16]O). The trace element accelerator mass accelerator technique allows the breakup of interfering molecules. As is measured in a GeSi matrix with sensitivity significantly better than SIMS. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]