julilili42/papers huggingface dataset:
Human CD4+ T Cells Displaying Viral Epitopes Elicit a Functional Virus-Specific Memory CD8+ T Cell Response
2007-05-01

Abstract The Ag-specific cellular recall response to herpes virus infections is characterized by a swift recruitment of virus-specific memory T cells. Rapid activation is achieved through formation of the immunological synapse and supramolecular clustering of signal molecules at the site of contact. During the formation of the immunological synapse, epitope-loaded MHC molecules are transferred via trogocytosis from APCs to T cells, enabling the latter to function as Ag-presenting T cells (T-APCs). The contribution of viral epitope expressing T-APCs in the regulation of the herpes virus-specific CD8+ T cell memory response remains unclear. Comparison of CD4+ T-APCs with professional APCs such as Ag-presenting CD40L-activated B cells (CD40B-APCs) demonstrated reduced levels of costimulatory ligands. Despite the observed differences, CD4+ T-APCs are as potent as CD40B-APCs in stimulating herpes virus-specific CD8+ T cells resulting in a greater than 35-fold expansion of CD8+ T cells specific for dominant and subdominant viral epitopes. Virus-specific CD8+ T cells generated by CD4+ T-APCs or CD40B-APCs showed both comparable effector function such as specific lysis of targets and cytokine production and also did not differ in their phenotype after expansion. These results indicate that viral epitope presentation by Ag-specific CD4+ T cells may contribute to the rapid recruitment of virus-specific memory CD8+ T cells during a viral recall response.
Crystal chemistry of hydration in aluminous orthopyroxene
2007-05-01

Hydrogen incorporation in aluminous orthopyroxene may control the generation of melt and dominate the seismic properties at the base of the Earth.s lithosphere. To clarify the substitution mechanism of H, we have synthesized, characterized, and refined the crystal structure of this potentially significant variant of orthopyroxene. The experimentally produced crystals are small needles up to approximately 20 × 20 × 100 μm in size. Electron microprobe chemical analysis indicates about 11.7 wt% Al2O3. FTIR spectra indicate 7500 ppmw H2O with absorbance features qualitatively similar to natural mantle orthopyroxenes. TEM imagery indicates that the phase is pure orthopyroxene with low concentrations of defects and inclusions. Cell-parameter refinement from single-crystal X-ray diffraction gives a = 18.1876(7) Å; b = 8.7352(7) Å; c = 5.1789 (5) Å, V = 822.79(11) Å3, which is 1.2% smaller than pure Mg anhydrous orthoenstatite. The crystal structure has been refined from single-crystal X-ray intensity data measured using a rotating anode X-ray generator, micro-focused X-ray beam, and CCD detector system. The refined structure indicates about 5% vacancy in M2 and significant Al occupancy in both M1 and T2, consistent with its composition, (Mg0.95,0.05)M2, (Mg0.79Al0.21)M1, (Al0.25Si0.75)T2 SiT1 O6. The existence of hydrous orthopyroxene in the mantle could absorb water released from olivine on decompression to delay the onset of melting in the spinel stability region in mantle peridotite compositions.
Bipolar cells in the “grouped retina” of the elephantnose fish (Gnathonemus petersii)
2007-05-01

To elucidate the specific properties of retinae with grouped photoreceptors the neural pathways in the outer and inner plexiform layer were studied. Photoreceptor bundles in this species consist of more than 100 rods and up to 50 cones, and are usually regarded as functional units. Golgi impregnation in thick and thin sections and light microscopy were used to identify bipolar cell types linking photoreceptors to amacrine and/or ganglion cells. Nine different types were distinguished based on their dendritic morphology and the position of the axon terminal in the inner plexiform layer. Small cells have dendritic fields smaller than the diameter of a photoreceptor bundle and are contacted mostly by cones. The dendritic field size of bushy cells matches that of a photoreceptor bundle; they are contacted mainly by rods. Flat cells receive about equal input from rods and cones; their dendritic field size exceeds the bundle diameter. Within the three major classes there are subtypes addressing three sublaminae of the inner plexiform layer, the proximal On-centre region (sl b), the distal Off-centre region (sl a) and a central sublayer (sl c) probably with transient activity. These observations suggest that cone vision has a spatial acuity better than the “bundle grain”. In rod dominated vision the resolution matches that of the bundles; for this pathway, the hypothesis of the bundle as a functional unit is confirmed. The mesopic flat cell pathway has a resolution inferior to the “bundle grain”; it may therefore be dedicated to movement detection.
High-resolution Reconstruction of a Waxed Heart Specimen With Flat Panel Volume Computed Tomography and Rapid Prototyping
2007-05-01

A waxed piglet heart was scanned with a flat panel volume computed tomography scanner (voxel size, 0.25 mm). Virtual and real laser-sintered models showed excellent visual concordance with the original. Using an iterative-closest-point algorithm, a very low mean surface distance was found between the original and laser-sintered model (0.26 +/- 0.34 mm). These techniques allow submillimeter 3-dimensional virtual and real reconstructions without destroying the original and might be useful for teaching, research, and planning of cardiac interventions.
Weyl’s symbols of Heisenberg operators of canonical coordinates and momenta as quantum characteristics
2007-05-01

The knowledge of quantum phase flow induced under Weyl’s association rule by the evolution of Heisenberg operators of canonical coordinates and momenta allows to find the evolution of symbols of generic Heisenberg operators. The quantum phase flow curves obey the quantum Hamilton equations and play the role of characteristics. At any fixed level of accuracy of semiclassical expansion, quantum characteristics can be constructed by solving a coupled system of first-order ordinary differential equations for quantum trajectories and generalized Jacobi fields. Classical and quantum constraint systems are discussed. The phase-space analytic geometry based on the star-product operation can hardly be visualized. The statement “quantum trajectory belongs to a constraint submanifold” can be changed, e.g., to the opposite by a unitary transformation. Some of the relations among quantum objects in phase space are, however, left invariant by unitary transformations and support partly geometric relations of belonging and intersection. Quantum phase flow satisfies the star-composition law and preserves Hamiltonian and constraint star functions.
Synthesis, Structure and Acid-Base Behaviour of Some 4-Hydroxycoumarin Derivatives
2007-05-01

Abstract The compound 3,3′-[(4-hydroxy-3-methoxy-5-nitrophenyl)methylene]-bis(4-hydroxy-2H-1- benzopyran-2-one) (1) crystallizes in the monoclinic system, space group P2 1 /n, with cell constants a = 16.859(4), b = 6.1624(15), c = 25.164(4) Å , β = 98.019(19)°. The two 4-hydroxycoumarin fragments are intramolecularly hydrogen-bonded between hydroxyl and carbonyl groups. The pH-dependent color changes of 4-hydroxycoumarin derivatives were studied by means of potentiometric and spectrophotometric titration. On the basis of the results obtained, the use of 3,3′-[(4-hydroxy-3- methoxy-5-nitrophenyl)methylene]-bis(4-hydroxy-2H-1-benzopyran-2-one) as an indicator in alkalimetry and acidimetry is proposed.
Predictability of future economic growth and the credibility of monetary regimes in Germany, 1870–2003
2007-05-01

Our study tries to quantify the predictability of economic growth and links it to the capability of regimes to fight against inflation. A regime with a high persistence of inflation and, hence, low credibility exhibits a high level of predictability of economic growth using the yield curve as indicator. Based on structural VAR models, we evaluate the credibility of monetary regimes in Germany from 1870 to 2003. The period of the Classical Gold Standard exhibited the highest credibility compared to the interwar period, the Bretton Woods and free float era. The reliability of the Bretton Woods agreement deteriorated years before the official breakdown in 1971
LRRC15 in breast cancer: Description of two transcript isoforms and identification of genotypical polymorphisms in cells lines with different invasion abilities
2007-05-01

2020 Background A fundamental step during the progression of breast cancer is the transition from ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC). At this point, cancer cells gain the potential for spreading and metastasis. In a previous microarray analysis we showed that expression of LRRC15 is up-regulated in IDC compared to DCIS (Schuetz et al., Cancer Res. 2006;66:5278-86). Aim The aim of this study was to validate LRRC15’s differential expression during tumor progression and to functionally analyse its role in invasive breast cancer cells. Methods Three different breast epithelial cell lines with described differences in their abilitiy to form tumors and to invade surrounding tissue (MCF10A, MCF7, and MDA-MB-231) were analysed for the expression level of LRRC15. Full length cDNAs were synthesized from MCF10A and MDA-MB-231 cells and analysed for single nucleotide polymorphisms (SNPs). The expression pattern of two LRRC15 isoforms was investigated by RT-PCR in normal versus matched cancer tissue and between different invasive breast tumors, respectively. Results The expression of LRRC15 was highly up-regulated in invasive MDA-MB-231 cells. Sequencing of different cDNA clones provided ten SNPs throughout the open reading frame between non-invasive MCF10A and highly invasive MDA-MB-231 cells. Two SNPs cause amino acid changes at positions 264 and 286 in the predicted protein sequence of LRRC15 in MDA-MB-231 cells. MCF10A and MDA-MB-231 cells are homozygous carriers of the two respective polymorphisms. Additionally, the differential expression pattern of two LRRC15 transcript variants in normal versus matched cancer tissue and between different invasive breast tumors was verified. The larger isoform contains an alternative start codon (ATG) which alters the N-terminal signaling peptide of LRRC15 protein. >Conclusion >Our data show that LRRC15 is not only differentially expressed between DCIS and IDC but is also expressed in different isoforms. Differences in the amino acid sequence might change its role in the process of tumor cell invasion. Therefore, LRRC15 might be a potential prevention target for future therapeutic regimes.
Fusion of HSV-1 VP22 to a bifunctional chimeric SuperCD suicide gene compensates for low suicide gene transduction efficiencies
2007-05-01

Low transduction efficiencies of viral and non-viral vectors still remain a major limitation in suicide gene therapy. The HSV-1 tegument protein VP22 can spread from cells where it is produced to surrounding recipient cells, thus making it a promising tool for compensation of inadequate gene transfer efficiencies. In our previous study, we focused on the optimization of the cytosine deaminase (CD) suicide gene system for the treatment of hepatocellular carcinoma. The fusion of yeast cytosine deaminase (YCD) to yeast uracil-phosphoribosyltransferase designated SuperCD was shown to be catalytically superior to the YCD gene in our previous study. The aim of our study was to investigate whether fusion of the bifunctional SuperCD suicide gene to VP22 could further potentiate suicide gene therapy efficiency. C- and N-terminal fusions of SuperCD linked in-frame with VP22 were created and cloned into recombinant adenoviral vectors. Under incubation with the prodrug 5-fluorocytosine (5-FC) a strong enhancement in suicide gene induced target cell cytotoxicity was observed whereby the C-terminal fusion of VP22 to SuperCD (VP22-SuperCD) caused the most tremendous decrease in IC50 compared to both Ad-SuperCD transduced and uninfected hepatoma control cells. Optimization of the bystander effect mediated by the intercellular transport of VP22-fusion proteins was demonstrated by cytotoxicity assays performed with a mixture of adenoviral transduced cells and naïve uninfected cells. Immunofluorescence analysis of adenoviral transduced COS-1 cells coplated with naïve HeLa cells further confirmed the unique property of VP22 for intercellular trafficking.
Rapid healing of a late diagnosed sickle cell leg ulcer using a new combination of treatment methods
2007-05-01

Approximately 5% of the world’s population are carriers of the genetic alterations associated with sickle cell trait and thalassaemia — the percentage is as high as 25% in some regions.1 Sickle cell disorders include all states in which a sickle cell gene has been inherited, but sickle cell diseases refer to states in which a morbid condition ensues, such as haemoglobin sickle cell disease and haemoglobin S-β-thalassaemia. The term sickle cell anaemia is reserved for the homozygous state of haemoglobin S (HbSS).
PFAAM An Active Appearance Model based Particle Filter for both Robust and Precise Tracking
2007-05-01

Model based tracking is one key component of many systems today, e.g. within video surveillance or human computer interfaces (HCI). Our approach consists of a combination of particle filters (PFs) and active appearance models (AAMs): the PFAAM. It combines the robustness of PFs with the precision of AAMs. Experimental results are given. PFAAM shows superior perfomance compared to both standard AAMs and PFs using AAMs as cues only, i.e. without using a local optimization loop.
Self-Localization in Scanned 3DTV Sets
2007-05-01

Future 3D Television applications will offer the viewer to freely choose his viewpoint during transmission. A lot of research in the field of 3DTV therefore concentrated on capturing photo-realistic 3D models of studio or movie sets. In this paper, however, we concentrate on the problem of self-localization within such scenes. As input we expect a 3D model of an arbitrary environment. Therein, we are able to localize a low-cost portable sensor-system based on a 3D time-of-flight camera. Point clouds acquired with this system from arbitrary viewpoints are registered to the given model in order to estimate its position and orientation in the scene.
Travel-relatedSalmonellaAgama, Gabon
2007-05-01

To the Editor: Traveler's diarrhea affects >50% of travelers to regions such as sub-Saharan Africa (1).Worldwide, enterotoxigenic Escherichia coli is the leading bacterial pathogen that causes traveler's diarrhea, followed by Campylobacter jejuni and then Salmonella spp., which are the causative pathogens for >25% of traveler's diarrhea in Africa (1).Nontyphoidal salmonellosis is mostly caused by the Salmonella serotypes Enteritidis and Typhimurium (2).To our knowledge, only a few cases of salmonellosis due to S. Agama have been reported in medical literature, none as a travel-related disease (3,4).S. Agama was characterized in 1956 as a new serotype of Salmonella enterica from the feces of the agama lizard (Agama agama) in Nigeria (5).Subsequently, S. Agama was isolated from geckos and mammals in Africa (4,6,7) and the United Kindgom (8,9).Human infections with S. Agama were once reported in Nigeria and related to the lizards as possible reservoirs (4).Another clinical case of S. Agama infection was described in France in a 9-month-old child with fever and diarrhea (3); fruits
Rapid Development of Band Keratopathy of Corneal Graft Associated with Treatment with Intracameral Recombinant Tissue Plasminogen Activator for Postoperative Fibrin Reaction
2007-05-01

Purpose. To report a corneal transplant complication associated with intracameral recombinant tissue plasminogen activator (rTPA) treatment of postoperative fibrin reaction. Methods. In a 71-year-old patient, a triple procedure was performed for perforated rheumatic ulcer and secondary cataract. Results. A dense band keratopathy developed rapidly within 36 hours after the use of intracameral injection of rTPA for the treatment of a dense fibrin clot. Conclusions. This is the first report of rapid development of massive band keratopathy in a corneal graft after triple procedure and treatment with intracameral rTPA. Intracameral rTPA should be used with caution in patients with attenuated endothelium.
Nutritional Supplement and Illicit Drug Use in Elite Athletes
2007-05-01

It has been postulated that the use of nutritional supplements (NS) constitutes a gateway for the use of illicit drugs and doping substances. PURPOSE: In the present study, we examined this hypothesis in competitive athletes, paying particular attention to their sources of information and supply, as well as to their motives. METHODS: A total of 536 elite athletes were questioned using an anonymous questionnaire. Using logistic regression analysis, multivariate odds ratios were estimated to investigate the probability of NS use with other parameters and to develop a NS user profile. RESULTS: 55.4% of the athletes responded positively to having used NS. NS use was positively correlated with age, with the desire to enhance performance in order to become an Olympic or World Champion, as well as with knowledge about NS. NS was negatively correlated with training frequency and the use of nicotine. The most commonly mentioned supplements were vitamins (44.0%) and minerals (35.8%). Reasons for using NS were primarily the need to enhance recovery from injuries and the desire for athletic success. Athletes reported that their sources of information were mainly sports physicians (41.0%) and coaches (35.4%). The main sources of supply named were pharmacies (57.5%) and drugstores (29.6%). CONCLUSION: Our results demonstrate that NS are used on a large scale in elite sports. Since NS are commonly contaminated with anabolic steroids, athletes in controlled elite sports in particular should be educated about potential negative consequences to their eligibility due to drug screening results. Sports physicians and pharmacists, on the basis of their specialized knowledge and close contact with athletes, should take on the responsibility of educating athletes about NS. A slippery slope hypothesis of NS paving the way towards the use of either natural stimulants or illicit drugs is not supported by our data.
Sanchk: an sql-based validation system for san configuration
2007-05-01

Storage area networks (SANs) connect groups of storage devices to servers over fast interconnects using protocols like Fibre Channel or iSCSI, so that storage resources can be assigned to servers in a flexible and scalable way. An important challenge is controlling the complexity of the SAN configuration resulting from the high scalability of the network and the diversity and the interconnectivity of the devices. Policy- based validation has been proposed earlier as a solution to this configuration problem. We propose a light-weight, SQL-based solution that uses existing well-known technologies to implement such a validation system. Our approach is based on a relational database which stores configuration data extracted from the system via a WBEM standard interface. In contrast to other approaches, we use SQL to define our policy rules as executable checks on these configuration data. Each rule is embedded in a test case, defined by an XML schema, which combines each check with an explanation component and an action component. These components retrieve information about the SAN components that cause the check to fail and provide methods that will be invoked on a success or a failure of the test. Although the approach is more general, we focus on the application for Storage Area Networks. We also give some example policies for SAN configuration and their implementations and show how in addition all policy types presented by Agrawal et al. (2004) can be formulated as SQL queries by our method.
An Integrated Approach for Managing Peer-to-Peer Desktop Grid Systems
2007-05-01

In this paper we propose a comprehensive integrated management architecture for large-scale desktop grid systems. By visualization of managed entities and automation of repetitive management tasks, we deal with the additional complexity induced by the size of these systems. We introduce the concepts of peer-to-peer and disconnected management to cope with network segmentation and node volatility, which are both intrinsic to desktop grid systems. By studying real-world use cases, we demonstrate the applicability of our solution.
A Mechanism for Charging System Self-Configuration in Next Generation Mobile Networks
2007-05-01

Self-management is an emerging idea in charging system research taken over from autonomic computing to address the complexity problem of system deployment, maintenance and administration and to improve the performance and flexibility of the charging system what will as a whole eventually decrease its total cost of ownership. In this paper, we describe a mechanism for charging system self-configuration when new network or service elements that record charging information are added as well as for charging system self-optimisation during every-day operation.
The effect of respiratory gating on quantitative PET imaging in lung cancer
2007-05-01

256 Objectives: In PET/CT, motion in tissues such as the lungs results in overestimation of tracer-avid volumes of interest and underestimation of their intensities. Respiratory gating has been shown to reduce these effects in phantoms and sample patients. We demonstrate its effect in a clinical setting with a larger number of patients. Methods: Using a GE Discovery LS PET/CT scanner equipped with a Varian RPM respiratory gating system 18 patients with known pulmonary cancer received both ungated and gated 18FDG-PET/CT scans as part of their regular staging. Lesion volumes were determined in CT by direct measurement and in PET using adaptive thresholding (Erdi et al. 1997) with software running on GE AW and Xeleris workstations. Maximum, minimum and average SUVs were determined. Statistical significance was tested using a two-tailed paired Student’s t-test and confirmed with a Wilcoxon test. In order to rule out a confounding influence of image noise on the gated studies, signal-to-noise-ratios (SNRs) were compared. Results: With respiratory gating, the average lesion area per slice as well as extent in the Z direction were significantly lowered (by 15.5% and 10.3%, p = 0.014 and p = 0.007), resulting in a decrease in measured tumor volume of 44.5% (p = 0.025). The difference between lesion volumes in gated PET and CT was significantly lower than the difference in ungated PET and CT (-126.6%, p = 0.025). Gating increased SUVmax by 22.4% (p