julilili42/papers huggingface dataset:
Involvement of E‐cadherin and β‐catenin in germ cell tumours and in normal male fetal germ cell development
2004-08-12

Abstract Intercellular contacts, mediated by E‐cadherin, are essential for germ cell migration and maturation. Furthermore, it has been suggested that decrease or loss of E‐cadherin correlates with tumour progression and invasive behaviour. β‐catenin is involved in a number of different processes, including cell–cell interaction when bound to cadherins, and determination of cell fate in pluripotent cells when activated via the Wnt signal‐transduction pathway. To shed more light on the role of these factors in normal fetal germ cell development and the pathogenesis of germ cell tumours (GCTs), the present study investigated the presence and localization of E‐cadherin and β‐catenin by immunohistochemistry. E‐cadherin was only weakly expressed in or absent from fetal germ cells of the second and third trimesters, and was not expressed in carcinoma in situ /intratubular germ cell neoplasia unclassified (CIS/ITGCNU) and gonadoblastoma, the precursor of an invasive GCT in dysgenetic gonads. In GCTs, it was generally not expressed in seminoma and dysgerminoma, but was found in the vast majority of non‐seminoma cells. β‐catenin was found in the cytoplasm of fetal germ cells at all gestational ages and in spermatogenesis in post‐pubertal testes. It was also present in CIS/ITGCNU and gonadoblastoma. Whereas seminomas and dysgerminoma were negative, non‐seminoma cells were frequently found to express β‐catenin. Expression of both factors therefore reflects the degree of differentiation of these tumours. No differences for either E‐cadherin or β‐catenin were observed between samples of tumours resistant or sensitive to chemotherapy, and E‐cadherin expression did not correlate with vascular invasion. E‐cadherin and β‐catenin therefore play a role in both normal and malignant germ cell development and differentiation that warrants further investigation, but they seem to be of limited value as predictive or prognostic factors in GCTs. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley &amp; Sons, Ltd.
Bremsstrahlung energy loss of electrons passing through a plasma
2004-08-12

The average energy loss due to bremsstrahlung emission of electrons passing through a plasma is calculated. In particular, the contribution of electron-electron bremsstrahlung is specified. The bremsstrahlung losses are compared with the energy loss by collisions with ambient electrons. Above electron energies of 510 MeV the energy loss due to bremsstrahlung predominates.
Semiquantitative Assessment of Myocardial Perfusion Using Magnetic Resonance Imaging
2004-08-12

Subdivision of radial myocardial segments is essential in analysis of magnetic resonance first-pass perfusion series. Semiquantitative perfusion parameters possess different sensitivities for the detection of perfusion deficits.
Engagement of the CD137 (4‐1BB) costimulatory molecule inhibits and reverses the autoimmune process in collagen‐induced arthritis and establishes lasting disease resistance
2004-08-13

Summary Agonistic antibodies against CD137 act as costimulators in the activation of CD8 T cells. They enhance the immune response against syngeneic tumour grafts and suppress T cell‐dependent humoral immune responses in vivo . The present study was undertaken to determine whether suppression of antibody production by anti‐CD137 mAb affects the development of collagen‐induced arthritis (CIA). Male DBA/1J mice were immunized with bovine collagen II (CII) and treated with an agonistic anti‐CD137 mAb or an isotype‐matched control mAb. Mice were assessed regularly for macro‐ and microscopic signs of arthritis and for the appearance of collagen‐specific antibody production. Interferon (IFN)‐γ determination, FACS analysis of splenocytes and histopathological joint examinations were performed after the animals were killed. Administration of anti‐CD137 mAb at the time of collagen immunization blocked the development of disease and inhibited the humoral immune response against CII. Agonistic anti‐CD137 mAb exhibited therapeutic efficacy even after the immune response to CII had succeeded and the disease became apparent. Furthermore, it induced a protective memory in the animals, enabling resistance to subsequent challenges with the pathogenic antigen. Our results suggest a key role for CD137 in the pathogenesis of CIA. This model provides insights into immunoregulatory conditions that control the pathogenesis of autoimmune diseases.
The benefit of functional???anatomical imaging with [18F]fluorodeoxyglucose utilizing a dual-head coincidence gamma camera with an integrated X-ray transmission system in non-small cell lung cancer
2004-08-13

Functional imaging in NSCLC with this dual-head gamma camera is superior to morphological imaging by CT, although inferior to dedicated PET imaging. Combined functional-anatomical imaging has the potential to improve staging and localization procedures before surgery or radiotherapy.
Crumbs homologue 1 is required for maintenance of photoreceptor cell polarization and adhesion during light exposure
2004-08-15

Loss of Crumbs homologue 1 (CRB1) function causes either the eye disease Leber congenital amaurosis or progressive retinitis pigmentosa, depending on the amount of residual CRB1 activity and the genetic background. Crb1 localizes specifically to the sub-apical region adjacent to the adherens junction complex at the outer limiting membrane in the retina. We show that it is associated here with multiple PDZ protein 1 (Mupp1), protein associated with Lin-7 (Pals1 or Mpp5) and Mpp4. We have produced Crb1-/- mice completely lacking any functional Crb1. Although the retinas are initially normal, by 3-9 months the Crb1-/- retinas develop localized lesions where the integrity of the outer limiting membrane is lost and giant half rosettes are formed. After delamination of the photoreceptor layer, neuronal cell death occurs in the inner and outer nuclear layers of the retina. On moderate exposure to light for 3 days at 3 months of age, the number of severe focal retinal lesions significantly increases in the Crb1-/- retina. Crb2, Crb3 and Crb1 interacting proteins remain localized to the sub-apical region and therefore are not sufficient to maintain cell adhesion during light exposure in Crb1-/- retinas. Thus we propose that during light exposure Crb1 is essential to maintain, but not assemble, adherens junctions between photoreceptors and Müller glia cells and prevents retinal disorganization and dystrophy. Hence, light may be an influential factor in the development of the corresponding human diseases.
MHC Class II Isotype- and Allele-Specific Attenuation of Experimental Autoimmune Encephalomyelitis
2004-08-15

Abstract Most autoimmune diseases are associated with certain MHC class II haplotypes. Autoantigen-based specific immune therapy can lead either to beneficial or, in the context of inflammatory conditions, detrimental outcomes. Therefore, we designed a platform of peptides by combinatorial chemistry selected in a nonbiased Ag-independent approach for strong binding to the rat MHC class II isotype RT1.Dn allelic product of the RT1n haplotype that is presenting autoantigen in myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis in LEW.1N rats. Peptide p17 (Ac-FWFLDNAPL-NH2) was capable of suppressing the induction of and also ameliorated established experimental autoimmune encephalomyelitis. MHC class II isotype and allele specificity of the therapeutic principle were demonstrated in myelin basic protein-induced experimental autoimmune encephalomyelitis in LEW rats bearing the RT1l haplotype. A general immunosuppressive effect of the treatment was excluded by allogeneic heart transplantation studies. In vitro studies demonstrated the blocking effect of p17 on autoantigenic T cell responses. We thus demonstrate a rational design of strong MHC class II-binding peptides with absolute isotype and allele specificity able to compete for autoantigenic sequences presented on disease-associated MHC class II molecules.
Prevalent expression of the immunostimulatory MHC class I chain–related molecule is counteracted by shedding in prostate cancer
2004-08-16

The MHC class I chain-related molecules (MICs) have previously been shown to be induced on most epithelial tumor cells. Engagement of MIC by the activating immune receptor NKG2D triggers NK cells and augments antigen-specific CTL anti-tumor immunity. The MIC-NKG2D system was proposed to participate in epithelial tumor immune surveillance. Paradoxically, studies suggest that tumors may evade MIC-NKG2D-mediated immunity by MIC shedding-induced impairment of effector cell function. Here we demonstrate the first evidence to our knowledge of a significant correlation of MIC shedding and deficiency in NK cell function with the grade of disease in prostate cancer. MIC is widely expressed in prostate carcinoma. The presence of surface target MIC, however, is counteracted by shedding. A significant increase in serum levels of soluble MIC (sMIC) and deficiency in NK cell function was shown in patients with advanced cancer. Finally, the deficiency in NK cell function can be overcome by treatment with IL-2 or IL-15 in vitro. Our results suggest that (a) deficiency in MIC-NKG2D immune surveillance may contribute to prostate cancer progression, (b) sMIC may be a novel biomarker for prostate cancer, and (c) using cytokines to restore MIC-NKG2D-mediated immunity may have clinical significance for prostate cancer in cell-based adaptive immunotherapy.
Prevalent expression of the immunostimulatory MHC class I chain–related molecule is counteracted by shedding in prostate cancer
2004-08-16

The MHC class I chain–related molecules (MICs) have previously been shown to be induced on most epithelial tumor cells. Engagement of MIC by the activating immune receptor NKG2D triggers NK cells and augments antigen-specific CTL anti-tumor immunity. The MIC-NKG2D system was proposed to participate in epithelial tumor immune surveillance. Paradoxically, studies suggest that tumors may evade MIC-NKG2D–mediated immunity by MIC shedding–induced impairment of effector cell function. Here we demonstrate the first evidence to our knowledge of a significant correlation of MIC shedding and deficiency in NK cell function with the grade of disease in prostate cancer. MIC is widely expressed in prostate carcinoma. The presence of surface target MIC, however, is counteracted by shedding. A significant increase in serum levels of soluble MIC (sMIC) and deficiency in NK cell function was shown in patients with advanced cancer. Finally, the deficiency in NK cell function can be overcome by treatment with IL-2 or IL-15 in vitro. Our results suggest that (a) deficiency in MIC-NKG2D immune surveillance may contribute to prostate cancer progression, (b) sMIC may be a novel biomarker for prostate cancer, and (c) using cytokines to restore MIC-NKG2D–mediated immunity may have clinical significance for prostate cancer in cell-based adaptive immunotherapy.
Self-Synchronization and Dissipation-Induced Threshold in Collective Atomic Recoil Lasing
2004-08-16

Networks of globally coupled oscillators exhibit phase transitions from incoherent to coherent states. Atoms interacting with the counterpropagating modes of a unidirectionally pumped high-finesse ring cavity form such a globally coupled network. The coupling mechanism is provided by collective atomic recoil lasing, i.e., cooperative Bragg scattering of laser light at an atomic density grating, which is self-induced by the laser light. Under the rule of an additional friction force, the atomic ensemble is expected to undergo a phase transition to a state of synchronized atomic motion. We present the experimental investigation of this phase transition by studying the threshold behavior of this lasing process.
Majorana neutrino masses, neutrinoless double beta decay, and nuclear matrix elements
2004-08-17

The effective Majorana neutrino mass is evaluated by using the latest results of neutrino oscillation experiments. The problems of the neutrino mass spectrum,absolute mass scale of neutrinos and the effect of CP phases are addressed. A connection to the next generation of the neutrinoless double beta decay (0nbb-decay) experiments is discussed. The calculations are performed for 76Ge, 100Mo, 136Xe and 130Te by using the advantage of recently evaluated nuclear matrix elements with significantly reduced theoretical uncertainty. An importance of observation of the 0nbb-decay of several nuclei is stressed.
High-performance magnetic field sensor based on superconducting quantum interference filters
2004-08-17

We have developed an absolute magnetic field sensor using a superconducting quantum interference filter (SQIF) made of high-Tc grain-boundary Josephson junctions. The device shows the typical magnetic-field-dependent voltage response V(B), which is a sharp deltalike dip in the vicinity of zero-magnetic field. When the SQIF is cooled with magnetic shield, and then the shield is removed, the presence of the ambient magnetic field induces a shift of the dip position from B0≈0 to a value B≈B1, which is about the average value of the Earth’s magnetic field, at our latitude. When the SQIF is cooled in the ambient field without shielding, the dip is first found at B≈B1, and the further shielding of the SQIF results in a shift of the dip towards B0≈0. The low hysteresis observed in the sequence of experiments (less than 5% of B1) makes SQIFs suitable for high precision measurements of the absolute magnetic field. The experimental results are discussed in view of potential applications of high-Tc SQIFs in magnetometry.
Lack of phylogeography in European mammals before the last glaciation
2004-08-18

In many extant animal and plant species in Europe and North America a correlation exists between the geographical location of individuals and the genetic relatedness of the mitochondrial (mt) DNA sequences that they carry. Here, we analyze mtDNA sequences from cave bears, brown bears, cave hyenas, and Neandertals in Europe before the last glacial maximum and fail to detect any phylogeographic patterns similar to those observed in extant species. We suggest that at the beginning of the last glacial maximum, little phylogeographic patterns existed in European mammals over most of their geographical ranges and that current phylogeographic patterns are transient relics of the last glaciation. Cycles of retreat of species in refugia during glacial periods followed by incomplete dispersal from one refugium into other refugia during interglacial periods is likely to be responsible for the deep genetic divergences between phylogeographic clusters of mtDNA seen today.
Unveiling the Origin of Shape Coexistence in Lead Isotopes
2004-08-18

Shape coexistence in the nuclei (182-192)Pb is analyzed with the Hartree-Fock-Bogoliubov approach and the Gogny force. Good agreement with the experimental energies is found for the coexisting spherical, oblate, and prolate states. Contrary to the established interpretation, it is found that the low-lying prolate and oblate 0+ states are predominantly characterized by neutron correlations whereas the protons behave, in general, rather as spectators than playing an active role.
Recruitment of Periventricular Parietal Regions in Processing Cluttered Point-Light Biological Motion
2004-08-18

Recent findings point to the existence of a cortical-subcortical parietal network that drives attention-related integration of features and elements. Here we ask whether the functioning of this network might be modulated by early periventricular lesions. To this end, a cohort of adolescents who were born premature with different severity of bilateral periventricular leukomalacia (PVL) and two groups of matched peers (term-born adolescents and former preterms with normal MRI scan) were shown a set of impoverished point-light stimuli. Observers had to detect a point-light walker embedded in an array of distracters mimicking the motion of the target's dots. Patients exhibited higher susceptibility to distortions caused by distracters. In patients only, sensitivity to the point-light figure highly correlates not just with performance on additionally administered feature integration tasks but also on visual attention-demanding IQ tasks. Moreover, the sensitivity index, as well as the values of both IQ factors, decreases with an increase in the volumetric PVL extent in the parieto-occipital region. No relationship was found between these variables and the lesion extent in the frontal or temporal periventricular regions. The data suggest that visual integration and attention in processing cluttered point-light displays are intimately connected. Most importantly, periventricular parieto-occipital regions might be part of a distributed network recruited in deployment of the posterior attentional system. The functioning of this system seems to be vulnerable to bilateral periventricular damage even if it occurs very early in brain development.
Combined antiangiogenic gene therapy with sflt and endostatin is highly effective in a rat model of hepatocellular carcinoma
2004-08-18

The multiplicity of regulators acting in the process of tumor angiogenesis offers diverse molecular targets for an antiangiogenic therapy. On the other hand, therapeutical attempts to antagonize one of these players could be equalized by upregulation of another proangiogenic factor leading to some kind of resistance to antiangiogenic therapy. A combination therapy addressing two or more angiogenic targets could therefore be useful. Growth of Hepatocellular carcinoma, an uncurable disease in most cases so far, is supposed to be a suitable target for antiangiogenic therapy.
Bartonella henselae inhibits apoptosis in Mono Mac 6 cells
2004-08-20

Bartonella henselae causes the vasculoproliferative disorders bacillary angiomatosis and peliosis probably resulting from the release of vasculoendothelial growth factor (VEGF) from infected epithelial or monocytic host cells. Here we demonstrate that B. henselae in addition to VEGF induction was also capable of inhibiting the endogenous sucide programme of monocytic host cells. Our results show that B. henselae inhibits pyrrolidine dithiocarbamate (PDTC)-induced apoptosis in Mono Mac 6 cells. B. henselae was observed to be present in a vacuolic compartment of Mono Mac 6 cells. Direct contact of B. henselae with Mono Mac 6 cells was crucial for inhibition of apoptosis as shown by the use of a two-chamber model. Inhibition of apoptosis was paralleled by diminished caspase-3 activity which was significantly reduced in PDTC-stimulated and B. henselae-infected cells. The anti-apoptotic effect of B. henselae was accompanied by (i) the activation of the transcription factor NF-kappaB and (ii) the induction of cellular inhibitor of apoptosis proteins-1 and -2 (cIAP-1, -2). Our results suggest a new synergistic mechanism in B. henselae pathogenicity by (i) inhibition of host cell apoptosis via activation of NF-kappaB and (ii) induction of host cell VEGF secretion.
Altered processing of pain‐related information in patients with fibromyalgia
2004-08-21

Abstract Pressure pain thresholds (PPTs) and event‐related potentials (ERPs) elicited by emotional words were analyzed in 12 patients with fibromyalgia (FM) and 12 matched healthy subjects. PPTs were assessed at the middle finger of both hands, before and after the experiment. Overall, FM patients and healthy subjects did not differ in PPT. Nevertheless, FM patients as compared with healthy controls were characterized by a significant enhancement of pain sensitivity from the beginning to the end of the experiment indicating a long lasting sensitization due to repeated stimulation. ERPs were recorded during a language decision task where subjects had to react to unpleasant pain‐related and emotionally neutral words depending on syntactic or orthographic cues. An emotional category effect was observed on N400 and P300 components of the ERP, indicating that unpleasant words elicited more positive amplitudes than neutral words. A significant group effect was observed on P200 amplitudes, showing reduced amplitudes in FM patients as compared to healthy controls. Furthermore, unpleasant pain‐related compared to neutral words triggered significantly enhanced late positive slow waves in healthy controls, while a comparable effect was not found in FM patients. The ERP and PPT data suggest that FM patients are characterized by an altered cognitive processing of pain‐related information and by an abnormal adaptation to mechanical pain stimuli, respectively.
Identification of a DO white dwarf and a PG 1159 star in the ESO SN Ia progenitor survey (SPY)
2004-08-23

\\n We present high-resolution VLT spectra of a new helium-rich DO\\n white dwarf (<ext-link ext-link-type="aoi">HE1314+0018</ext-link>) and a new PG 1159 star (<ext-link ext-link-type="aoi">HE1429-1209</ext-link>), which we identified in\\n the ESO SPY survey. We performed NLTE model atmosphere analyses and found\\n that the PG 1159 star is a low-gravity, extremely hot ( = 160 000 K,\\n = 6) star, having a carbon-helium dominated atmosphere with considerable\\n amounts of oxygen and neon (He = 38%, C = 54%, O = 6%, Ne = 2% by mass). It is\\n located within the planetary nebula nuclei instability strip, hence, future\\n searches for an associated PN as well as for stellar pulsations might be\\n successful. The DO white dwarf is a unique object. From the relative strength\\n of neutral and ionized helium lines we found ≈ 60 000 K,\\n however, the lines are extraordinarily strong and cannot be\\n fitted by any model. Similar problems were encountered with hot subdwarfs and\\n white dwarfs showing signatures of a super-hot wind. The reason is unknown.\\n \\n \\n
Deletion of the Ca2+-activated potassium (BK) α-subunit but not the BKβ1-subunit leads to progressive hearing loss
2004-08-24

The large conductance voltage- and Ca 2+ -activated potassium (BK) channel has been suggested to play an important role in the signal transduction process of cochlear inner hair cells. BK channels have been shown to be composed of the pore-forming α-subunit coexpressed with the auxiliary β1-subunit. Analyzing the hearing function and cochlear phenotype of BK channel α-(BKα –/– ) and β1-subunit (BKβ1 –/– ) knockout mice, we demonstrate normal hearing function and cochlear structure of BKβ1 –/– mice. During the first 4 postnatal weeks also, BKα –/– mice most surprisingly did not show any obvious hearing deficits. High-frequency hearing loss developed in BKα –/– mice only from ≈8 weeks postnatally onward and was accompanied by a lack of distortion product otoacoustic emissions, suggesting outer hair cell (OHC) dysfunction. Hearing loss was linked to a loss of the KCNQ4 potassium channel in membranes of OHCs in the basal and midbasal cochlear turn, preceding hair cell degeneration and leading to a similar phenotype as elicited by pharmacologic blockade of KCNQ4 channels. Although the actual link between BK gene deletion, loss of KCNQ4 in OHCs, and OHC degeneration requires further investigation, data already suggest human BK-coding slo1 gene mutation as a susceptibility factor for progressive deafness, similar to KCNQ4 potassium channel mutations.