| 1. |
- Lindén, Sara K., 1974, et al.
(författare)
-
MUC1 limits Helicobacter pylori infection both by steric hindrance and by acting as a releasable decoy.
- 2009
-
Ingår i: PLoS pathogens. - : Public Library of Science (PLoS). - 1553-7374. ; 5:10
-
Tidskriftsartikel (refereegranskat)abstract
- The bacterium Helicobacter pylori can cause peptic ulcer disease, gastric adenocarcinoma and MALT lymphoma. The cell-surface mucin MUC1 is a large glycoprotein which is highly expressed on the mucosal surface and limits the density of H. pylori in a murine infection model. We now demonstrate that by using the BabA and SabA adhesins, H. pylori bind MUC1 isolated from human gastric cells and MUC1 shed into gastric juice. Both H. pylori carrying these adhesins, and beads coated with MUC1 antibodies, induced shedding of MUC1 from MKN7 human gastric epithelial cells, and shed MUC1 was found bound to H. pylori. Shedding of MUC1 from non-infected cells was not mediated by the known MUC1 sheddases ADAM17 and MMP-14. However, knockdown of MMP-14 partially affected MUC1 release early in infection, whereas ADAM17 had no effect. Thus, it is likely that shedding is mediated both by proteases and by disassociation of the non-covalent interaction between the alpha- and beta-subunits. H. pylori bound more readily to MUC1 depleted cells even when the bacteria lacked the BabA and SabA adhesins, showing that MUC1 inhibits attachment even when bacteria cannot bind to the mucin. Bacteria lacking both the BabA and SabA adhesins caused less apoptosis in MKN7 cells than wild-type bacteria, having a greater effect than deletion of the CagA pathogenicity gene. Deficiency of MUC1/Muc1 resulted in increased epithelial cell apoptosis, both in MKN7 cells in vitro, and in H. pylori infected mice. Thus, MUC1 protects the epithelium from non-MUC1 binding bacteria by inhibiting adhesion to the cell surface by steric hindrance, and from MUC1-binding bacteria by acting as a releasable decoy.
|
|
| 2. |
|
|
| 3. |
- Birney, Ewan, et al.
(författare)
-
Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project
- 2007
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 447:7146, s. 799-816
-
Tidskriftsartikel (refereegranskat)abstract
- We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structure has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function.
|
|
| 4. |
- Chen, H., et al.
(författare)
-
The distribution of grating-coupled field of quantum well infrared photodetector using FDTD method
- 2007
-
Ingår i: Infrared Materials, Devices, and Applications. - : SPIE - International Society for Optical Engineering. - 9780819470102 ; , s. 68351E-
-
Konferensbidrag (refereegranskat)abstract
- For most commonly used GaAs/AlGaAs n-type quantum well infrared photodetectors (QWIPs), the normal incident absorption is not possible because of the transition rule. The optical grating is required to achieve high absorption quantum efficiencies. When some gratings are patterned on the metal plate, the polarization direction can be changed greatly because of the diffraction effect. Finite difference time domain (FDTD) method has been used to investigate the effect of a reflection metal grating on the couple efficiency previously. However, the authors only take one metal grating and apply periodic boundary condition along the grating direction due to the computation limit. For a real QWIP system, such simulation is crude. In this work we consider a real GaAs/AlGaAs QWIP with a wavelength response around 15um and use FDTD method to investigate the effect of a reflection metal grating on the electric field pattern and the couple efficiency. The simulating results show that the electric field pattern is not periodic for every metal grating in a real QWIP system. We have also studied the influence of the substrate thickness and the grating period on the electric field pattern and the couple efficiency. These results offer a guideline for the design of QWIP.
|
|
| 5. |
- He, G. S., et al.
(författare)
-
Stimulated Rayleigh-Bragg Scattering From a Two-Photon Absorbing CdSe-CdS-ZnS Quantum-Rods System : Optical Power Limiting and Phase-Conjugation
- 2008
-
Ingår i: IEEE Journal of Quantum Electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9197 .- 1558-1713. ; 44:9-10, s. 894-901
-
Tidskriftsartikel (refereegranskat)abstract
- This work reports the properties of stimulated Rayleigh-Bragg scattering (SRBS) from a two-photon absorbing CdSe-Cds-ZnS quantum-rods (QRs) solution in chloroform, excited by 1064-nm and similar to 13-ns laser pulses. The two-photon absorbing capability of the scattering medium, as well as the pump threshold, spectral structure, and pulse waveforms of the backward stimulated scattering were measured. Comparing to a pure solvent or an organic dye-solution, the semiconductor QR system has many advantages such as the lower pump threshold, higher energy transfer efficiency, and better photo-physical and photo-chemical stability. The measured output/input characteristic curve shows that the backward SRBS can enhance the optical power limiting performance that is based on two-photon absorption, backward stimulated scattering, and other nonlinear absorption mechanisms. In addition, the backward SRBS beam from our sample medium exhibits a fairly good optical phase-conjugation capability, so that the distortion influence from an inserted aberrator can be automatically removed.
|
|
| 6. |
- Hu, R., et al.
(författare)
-
Metallic Nanostructures as Localized Plasmon Resonance Enhanced Scattering Probes for Multiplex Dark-Field Targeted Imaging of Cancer Cells
- 2009
-
Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 113:7, s. 2676-2684
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we report the use of bioconjugated gold nanorods and silver nanoparticles as targeted localized surface plasmon resonance enhanced scattering probes for dark-field multiplex and transmission electron microscopy (TEM) imaging of pancreatic cancer cells. We take advantage of the spectrally widely separated localized plasmon resonance of the gold nanorods and silver nanoparticles which produce wavelength selective plasmon resonance scattering to allow multiplex imaging with high contrast. When the surfaces are functionalized, aqueous dispersions of bioconjugated gold nanorods and silver nanoparticles are prepared. We demonstrate receptor-mediated delivery of bioconjugated gold nanorods and silver nanoparticles simultaneously into pancreatic cancer cells, using multiplexed dark-field microscopy technique. We also show that the bioconjugated metallic nanostructures can be used for high-contrast TEM imaging as well.
|
|
| 7. |
|
|
| 8. |
- Malm, B. Gunnar, et al.
(författare)
-
Base resistance scaling for SiGeC HBTs with a fully nickel-silicided extrinsic base
- 2005
-
Ingår i: IEEE Electron Device Letters. - : IEEE Press. - 0741-3106 .- 1558-0563. ; 26:4, s. 246-248
-
Tidskriftsartikel (refereegranskat)abstract
- A novel SiGeC HBT process with a quasi-self-aligned emitter-base architecture and a fully nickel-silicided extrinsic base region has been developed. A very low total base resistance R-B was achieved along with simultaneous NiSi formation on the polycrystalline emitter and collector regions. Uniform silicide formation was obtained across the wafer, and the resistivity. of the Ni(SiGe:C) silicide layer was 24 mu Omega (.) cm. About 50-100 nm of lateral growth of silicide,. underneath the emitter pedestal was observed. DC and HF results with balanced f(T)/f(MAX) values of 41/42 GHz were demonstrated for 0.5 X 10 mu m(2) transistors.
|
|
| 9. |
- Preston, R J S, et al.
(författare)
-
Selective modulation of protein C affinity for EPCR and phospholipids by Gla domain mutation
- 2005
-
Ingår i: The FEBS Journal. - : Wiley. - 1742-464X .- 1742-4658. ; 272:1, s. 97-108
-
Tidskriftsartikel (refereegranskat)abstract
- Uniquely amongst vitamin K-dependent coagulation proteins, protein C interacts via its Gla domain both with a receptor, the endothelial cell protein C receptor (EPCR), and with phospholipids. We have studied naturally occurring and recombinant protein C Gla domain variants for soluble (s)EPCR binding, cell surface activation to activated protein C (APC) by the thrombin-thrombomodulin complex, and phospholipid dependent factor Va (FVa) inactivation by APC, to establish if these functions are concordant. Wild-type protein C binding to sEPCR was characterized with surface plasmon resonance to have an association rate constant of 5.23x10(5) M-1.s(-1), a dissociation rate constant of 7.61x10(-2) s(-1) and equilibrium binding constant (K-D) of 147 nM. It was activated by thrombin over endothelial cells with a K-m of 213 nM and once activated to APC, rapidly inactivated FVa. Each of these interactions was dramatically reduced for variants causing gross Gla domain misfolding (R-1L, R-1C, E16D and E26K). Recombinant variants Q32A, V34A and D35A had essentially normal functions. However, R9H and H10Q/S11G/S12N/D23S/Q32E/N33D/H44Y (QGNSEDY) variants had slightly reduced (
|
|
| 10. |
- Wakelee, Heather A., et al.
(författare)
-
Lung cancer incidence in never smokers
- 2007
-
Ingår i: Journal of Clinical Oncology. - 0732-183X .- 1527-7755. ; 25:5, s. 472-478
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Lung cancer is a leading cause of cancer death worldwide. Although smoking remains the predominant cause of lung cancer, lung cancer in never smokers is an increasingly prominent public health issue. However, data on this topic, particularly lung cancer incidence rates in never smokers, are limited. METHODS: We reviewed the existing literature on lung cancer incidence and mortality rates among never smokers and present new data regarding rates in never smokers from the following large, prospective cohorts: Nurses' Health Study; Health Professionals Follow-Up Study; California Teachers Study; Multiethnic Cohort Study; Swedish Lung Cancer Register in the Uppsala/Orebro region; and First National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study. RESULTS: Truncated age-adjusted incidence rates of lung cancer among never smokers age 40 to 79 years in these six cohorts ranged from 14.4 to 20.8 per 100,000 person-years in women and 4.8 to 13.7 per 100,000 person-years in men, supporting earlier observations that women are more likely than men to have non-smoking-associated lung cancer. The distinct biology of lung cancer in never smokers is apparent in differential responses to epidermal growth factor receptor inhibitors and an increased prevalence of adenocarcinoma histology in never smokers. CONCLUSION: Lung cancer in never smokers is an important public health issue, and further exploration of its incidence patterns, etiology, and biology is needed.
|
|
