julilili42/papers huggingface dataset:
A New Arylsulfate Sulfotransferase Involved in Liponucleoside Antibiotic Biosynthesis in Streptomycetes
2010-02-16

Sulfotransferases are involved in a variety of physiological processes and typically use 3'-phosphoadenosine 5'-phosphosulfate (PAPS) as the sulfate donor substrate. In contrast, microbial arylsulfate sulfotransferases (ASSTs) are PAPS-independent and utilize arylsulfates as sulfate donors. Yet, their genuine acceptor substrates are unknown. In this study we demonstrate that Cpz4 from Streptomyces sp. MK730-62F2 is an ASST-type sulfotransferase responsible for the formation of sulfated liponucleoside antibiotics. Gene deletion mutants showed that cpz4 is required for the production of sulfated caprazamycin derivatives. Cloning, overproduction, and purification of Cpz4 resulted in a 58-kDa soluble protein. The enzyme catalyzed the transfer of a sulfate group from p-nitrophenol sulfate (K(m) 48.1 microM, k(cat) 0.14 s(-1)) and methyl umbelliferone sulfate (K(m) 34.5 microM, k(cat) 0.15 s(-1)) onto phenol (K(m) 25.9 and 29.7 mM, respectively). The Cpz4 reaction proceeds by a ping pong bi-bi mechanism. Several structural analogs of intermediates of the caprazamycin biosynthetic pathway were synthesized and tested as substrates of Cpz4. Des-N-methyl-acyl-caprazol was converted with highest efficiency 100 times faster than phenol. The fatty acyl side chain and the uridyl moiety seem to be important for substrate recognition by Cpz4. Liponucleosides, partially purified from various mutant strains, were readily sulfated by Cpz4 using p-nitrophenol sulfate. No product formation could be observed with PAPS as the donor substrate. Sequence homology of Cpz4 to the previously examined ASSTs is low. However, numerous orthologs are encoded in microbial genomes and represent interesting subjects for future investigations.
Changing the phospholipid composition of Staphylococcus aureus causes distinct changes in membrane proteome and membrane‐sensory regulators
2010-02-16

Abstract The dynamic lipid composition of bacterial cytoplasmic membranes has a profound impact on vital bacterial fitness and susceptibility to membrane‐damaging agents, temperature, or osmotic stress. However, it has remained largely unknown how changes in lipid patterns affect the abundance and expression of membrane proteins. Using recently developed gel‐free proteomics technology, we explored the membrane proteome of the important human pathogen Staphylococcus aureus in the presence or absence of the cationic phospholipid lysyl‐phosphatidylglycerol (Lys‐PG). We were able to detect almost half of all theoretical integral membrane proteins and could reliably quantify more than 35% of them. It is worth noting that the deletion of the Lys‐PG synthase MprF did not lead to a massive alteration but a very distinct up‐ or down‐regulation of only 1.5 or 3.5% of the quantified proteins. Lys‐PG deficiency had no major impact on the abundance of lipid‐biosynthetic enzymes but significantly affected the amounts of the cell envelope stress‐sensing regulatory proteins such as SaeS and MsrR, and of the SaeS‐regulated proteins Sbi, Efb, and SaeP. These data indicate very critical interactions of membrane‐sensory proteins with phospholipids and they demonstrate the power of membrane proteomics for the characterization of bacterial physiology and pathogenicity.
Synthesis and Properties of Tetracyanamidosilicates ARE[Si(CN2)4]
2010-02-16

Tetracyanamidosilicates of the type ARE[Si(CN(2))(4)] with A = K, Rb, and Cs and RE = Y and La-Lu have been prepared by a solid-state metathesis reaction. The potassium compounds with RE = La-Gd crystallize orthorhombically in the space group P2(1)2(1)2. Rubidium as well as cesium compounds crystallize tetragonally in the space group I4. The luminescent properties of ARE[Si(CN(2))(4)]:Ln compounds with RE = Y, La, and Gd doped with 5 mol % Ln = Ce, Eu, or Tb were investigated. Temperature-dependent magnetic susceptibilities were measured for KGd[Si(CN(2))(4)]. The value of the magnetic moment is 7.3 mu(B)/Gd(3+) ion, which is in line with the expected value for the [Xe]4f(7) configuration of Gd(3+).
General characteristics of pp-collisions at LHC
2010-02-16

The quark-gluon string model is employed to study bulk production of hadrons and their spectra in inelastic pp collisions at ultrarelativistic energies.Good agreement with the available experimental data is obtained and predictions are made for pp collisions at full LHC energy √ s = 14 TeV.Fulfillment of scaling trends is checked both at midrapidity and in fragmentation regions.Feynman scaling and extended longitudinal scaling are found to hold in the fragmentation regions only.
Three Homologous Subunits Form a High Affinity Peptide-gated Ion Channel in Hydra
2010-02-17

Recently, three ion channel subunits of the degenerin (DEG)/epithelial Na(+) channel (ENaC) gene family have been cloned from the freshwater polyp Hydra magnipapillata, the Hydra Na(+) channels (HyNaCs) 2-4. Two of them, HyNaC2 and HyNaC3, co-assemble to form an ion channel that is gated by the neuropeptides Hydra-RFamides I and II. The HyNaC2/3 channel is so far the only cloned ionotropic receptor from cnidarians and, together with the related ionotropic receptor FMRFamide-activated Na(+) channel (FaNaC) from snails, the only known peptide-gated ionotropic receptor. The HyNaC2/3 channel has pore properties, like a low Na(+) selectivity and a low amiloride affinity, that are different from other channels of the DEG/ENaC gene family, suggesting that a component of the native Hydra channel might still be lacking. Here, we report the cloning of a new ion channel subunit from Hydra, HyNaC5. The new subunit is closely related to HyNaC2 and -3 and co-localizes with HyNaC2 and -3 to the base of the tentacles. Coexpression in Xenopus oocytes of HyNaC5 with HyNaC2 and -3 largely increases current amplitude after peptide stimulation and affinity of the channel to Hydra-RFamides I and II. Moreover, the HyNaC2/3/5 channel has altered pore properties and amiloride affinity, more similarly to other DEG/ENaC channels. Collectively, our results suggest that the three homologous subunits HyNaC2, -3, and -5 form a peptide-gated ion channel in Hydra that could contribute to fast synaptic transmission.
DTNBP1 (dysbindin) gene variants modulate prefrontal brain function in schizophrenic patients – support for the glutamate hypothesis of schizophrenias
2010-02-17

Dysbindin (DTNBP1) is a recently characterized protein that seems to be involved in the modulation of glutamatergic neurotransmission in the human brain, thereby influencing prefrontal cortex function and associated cognitive processes. While association, neuroanatomical and cellular studies indicate that DTNBP1 might be one of several susceptibility genes for schizophrenia, the effect of dysbindin on prefrontal brain function at an underlying neurophysiological level has not yet been explored for these patients. The NoGo‐anteriorization (NGA) is a topographical event‐related potential measure, which has been established as a valid neurophysiological marker of prefrontal brain function. In the present study, we investigated the influence of seven dysbindin gene variants on the NGA in a group of 44 schizophrenic patients. In line with our a priori hypothesis, one DTNBP1 polymorphism previously linked to schizophrenia (rs2619528) was found to be associated with changes in the NGA; however, the direction of this association directly contrasts with our previous findings in a healthy control sample. This differential impact of DTNBP1 gene variation on prefrontal functioning in schizophrenic patients vs. healthy controls is discussed in terms of abnormal glutamatergic baseline levels in patients suffering from schizophrenic illnesses. This is the first report on a role of DTNBP1 gene variation for prefrontal functioning at a basic neurophysiological level in schizophrenic patients. An impact on fundamental processes of cognitive response control may be one mechanism by which DTNBP1 gene variants via glutamatergic transmission contribute to the pathophysiology underlying schizophrenic illnesses.
Evaluation of the performance of the novel PapilloCheck® HPV genotyping test by comparison with two other genotyping systems and the HC2 test
2010-02-17

Abstract The novel PapilloCheck® genotyping test was compared with SPF10 PCR LiPav1 and PGMY09/11 on hybrid capture 2 (HC2)‐pretested samples. From results of 826 cervical samples detection rates and kappa values for the tests were calculated using a HPV type consensus definition. With PapilloCheck® HPV types 53, 56, and 33 were found with a sensitivity of 100%. The lowest detection rate was observed for HPV 35 (72.2%). The SPF10 PCR LiPav1 was found to be 100% positive for HPV 18, 31, 53, 56, and 35 and lowest for HPV 59 (81%). The PGMY09/11 system detected only HPV 59 at 100% detection rate and showed lowest sensitivity for HPV 56 (40.5%). Multiple infection rates ranged from 25.8% (PGMY09/11 PCR‐LBA), over 39.5% (PapilloCheck®) to 55.9% (SPF10 PCR LiPav1). In samples with higher viral DNA load detection rates and concordance between the genotyping tests increases. The kappa values in comparison to the HPV consensus type ranged from k = 0.21 to k = 0.82 for comparing SPF10 PCR with the HPV consensus type, while values for PGMY09/11 PCR ranged from k = 0 to k = 0.96 and were best for the PapilloCheck® (k = 0.49–0.98). Detection rates for the identification of high‐grade cervical intraepithelial neoplasia (CIN2+) ranged from 93.7% (PGMY09/11 PCR) to 98.4% (PapilloCheck®, SPF10 PCR, HC2). In conclusion, this study shows that the PapilloCheck® give comparable results to established PCR methods. However, these results also show a necessity for the standardization of genotype‐specific HPV detection assays. J. Med. Virol. 82:605–615, 2010. © 2010 Wiley‐Liss, Inc.
Retinal versus physical stimulus size as determinants of visual perception in simultanagnosia
2010-02-17

Patients with simultanagnosia following bilateral parieto-temporo-occipital brain damage show a characteristic impairment of global gestalt perception, while their perception of individual objects or elements remains intact. For instance, when shown 'hierarchical' stimuli comprising a larger global object (e.g. a large letter) made up from smaller components (e.g. multiple small letters), they typically report seeing one of the smaller components but not the global figure. Recent work on simultanagnosia revealed that global perception can be improved if local element spacing is reduced. However, it is still unclear whether the retinal separation or the physical (post-size-constancy) spatial separation is critical. Here, we presented various hierarchical global/local letter stimuli at different viewing distances and sizes to separate the impacts of retinal versus physical size. Our findings indicate a key role for visual angle in determining simultanagnosic perception. We observed that not only retinal spacing (in terms of visual angle) between local elements had a major impact on global perception in simultanagnosia, but also the physical size of the separation between local elements, provided that binocular cues to viewing distance were available. The results indicate both pre-size-constancy retinal influences and binocular-post-constancy influences upon conscious perception in simultanagnosia.
Regulation of renal tubular glucose reabsorption by Akt2/PKBβ
2010-02-17

Akt/PKB is known to regulate the facilitative glucose carrier GLUT4. Nothing is known, however, of the role of Akt/PKB in the regulation of renal epithelial transport. To explore whether Akt2/PKBβ influences the Na + -coupled glucose cotransporter SGLT1, human SGLT1 was expressed in Xenopus laevis oocytes with or without Akt/PKB, and electrogenic glucose transport was determined by dual-electrode voltage clamp. The coexpression of Akt/PKB in SGLT1-expressing oocytes was followed by an increase in glucose-induced currents. To study the functional significance of Akt/PKB-sensitive renal glucose transport, further experiments were performed in gene-targeted mice lacking functional Akt2/PKBβ ( akt2 −/− ) and in their wild-type littermates ( akt2 +/+ ). Plasma glucose concentration was significantly higher in akt2 −/− mice than in akt2 +/+ mice but was virtually identical to the plasma glucose concentration in fructose-treated akt2 +/+ mice. Urinary glucose excretion was significantly higher in akt2 −/− mice compared with akt2 +/+ mice with or without fructose treatment. Moreover, the glucose-induced depolarization of proximal tubular cells was significantly smaller in isolated, perfused renal tubules from akt2 −/− mice than in those from akt2 +/+ mice. In conclusion, Akt2/PKBβ plays a role in the regulation of renal glucose transport.
Planets in Mean‐Motion Resonance
2010-02-17

This chapter contains sections titled: Introduction Extrasolar Systems in Mean-Motion Resonance Planetary Migration Resonant Capture through Convergent Migration Matching Observed Systems Summary Acknowledgments References Further Reading
The interplay between individual and collective knowledge: technologies for organisational learning and knowledge building
2010-02-18

AbstractThis article presents a framework model that defines knowledge building as a co-evolution of cognitive and social systems. Our model brings together Nonaka's knowledge-creating theory and Luhmann's systems theory. It is demonstrated how collaborative knowledge building may occur – in an ideal situation – within an organisation, when people interact with each other using shared digital artefacts. For this purpose, three different technologies are introduced as examples: social-tagging systems, pattern-based task-management systems, and wikis. These examples have been chosen to demonstrate that knowledge building can occur with respect to both declarative and procedural knowledge. The differences and similarities between these technologies, as far as their potential for organisational knowledge building is concerned, are discussed in the light of the framework model.Keywords: collaborative systemsknowledge and informationknowledge communitiesknowledge management toolsorganisational learningtacit knowledge Additional informationNotes on contributorsJoachim KimmerleAbout the authorsJoachim Kimmerle is Assistant Professor in the Department of Applied Cognitive Psychology and Media Psychology at the University of Tuebingen. He holds a diploma in Psychology (Dipl.-Psych.) and a doctoral degree in natural sciences (Dr. rer. nat.). Prior to his current position, he worked as research associate at the Knowledge Media Research Center (Tuebingen) and visiting lecturer at the 'University of Cooperative Education' (Berufsakadamie) in Stuttgart.Ulrike CressUlrike Cress is Professor for empirical research in education. She is head of the research unit 'Design and implementation of integrative learning environments' at the Knowledge Media Research Center in Tuebingen. She studied Psychology at the University of Tuebingen (Diploma in 1993, doctoral degree Dr. rer. soc. in 2000 with a dissertation on self-regulated learning). In 2006 Dr. Cress obtained her venia legendi for Psychology after submitting a habilitation thesis on the information-exchange dilemma.Christoph HeldChristoph Held studied Psychology at the University of Regensburg and the University of Granada/Spain (Diploma 2006). He works as research scientist at the Knowledge Media Research Center. In his research unit he focuses on the field of individual and collaborative knowledge acquisition and knowledge exchange with social software on the World Wide Web and within enterprises. In 2008 he worked as visiting researcher at the Palo Alto Research Center (PARC).
Lepton flavor violating decays of vector mesons
2010-02-18

We estimate the rates of lepton flavor violating decays of the vector mesons . The theoretical tools are based on an effective Lagrangian approach without referring to any specific realization of the physics beyond the standard model responsible for lepton flavor violation (\\Lfv). The effective lepton-vector meson couplings are extracted from the existing experimental bounds on the nuclear conversion. In particular, we derive an upper limit for the \\Lfv branching ratio which is much more stringent than the recent experimental result presented by the SND Collaboration. Very tiny limits on \\Lfv decays of vector mesons derived in this letter make direct experimental observation of these processes unrealistic.
Self‐rated health status in spinocerebellar ataxia—Results from a European multicenter study
2010-02-19

Abstract Patient‐based measures of subjective health status are increasingly used as outcome measures in interventional trials. We aimed to determine the variability and predictors of subjective health ratings in a possible target group for future interventions: the spinocerebellar ataxias (SCAs). A consecutive sample of 526 patients with otherwise unexplained progressive ataxia and genetic diagnoses of SCA1 (117), SCA2 (163), SCA3 (139), and SCA6 (107) were enrolled at 18 European referral centers. Subjective health status was assessed with a generic measure of health related quality of life, the EQ‐5D (Euroqol) questionnaire. In addition, we performed a neurological examination and a screening questionnaire for affective disorders (patient health questionnaire). Patient‐reported health status was compromised in patients of all genotypes (EQ‐5D visual analogue scale (EQ‐VAS) mean 61.45 ± 20.8). Specifically, problems were reported in the dimensions of mobility (86.9% of patients), usual activities (68%), pain/discomfort (49.4%), depression/anxiety (46.4%), and self care (38.2%). Multivariate analysis revealed three independent predictors of subjective health status: ataxia severity, extent of noncerebellar involvement, and the presence of depressive syndrome. This model explained 30.5% of EQ‐VAS variance in the whole sample and might be extrapolated to other SCA genotypes. © 2010 Movement Disorder Society
Imaging of Primary and Secondary Inflammatory Diseases Involving Large and Medium-Sized Vessels and Their Potential Mimics: A Multitechnique Approach
2010-02-19

Large and medium-sized vessels are affected by many primary and secondary inflammatory disorders or mimicking conditions, often presenting similar imaging characteristics. Knowledge of distinctive imaging features such as location, length, and degree of vessel wall enhancement as well as the particular clinical settings will help the clinician in appropriately narrowing down the differential diagnosis.
ChemInform Abstract: The New Binary Tungsten Iodide W15I47.
2010-02-19

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Anti-GD2 with an FC point mutation reduces complement fixation and decreases antibody-induced allodynia
2010-02-20

Monoclonal antibodies against GD2 ganglioside, such as ch14.18, the human–mouse chimeric antibody, have been shown to be effective for the treatment of neuroblastoma. However, treatment is associated with generalized, relatively opiate-resistant pain. We investigated if a point mutation in ch14.18 antibody (hu14.18K332A) to limit complement-dependent cytotoxicity (CDC) would ameliorate the pain behavior, while preserving antibody-dependent cellular cytotoxicity (ADCC). In vitro, CDC and ADCC were measured using europium-TDA assay. In vivo, allodynia was evaluated by measuring thresholds to von Frey filaments applied to the hindpaws after injection of either ch14.18 or hu14.18K332 into wild type rats or rats with deficient complement factor 6. Other rats were pretreated with complement factor C5a receptor antagonist and tested following ch14.18 injection. The mutation reduces the antibody’s ability to activate complement, while maintaining its ADCC capabilities. Injection of hu14.18K322 (1 or 3 mg/kg) produced faster resolving allodynia than that engendered by ch14.18 (1 mg/kg). Injection of ch14.18 (1 mg/kg) into rats with C6 complement deficiency further reduced antibody-induced allodynia, while pre-treatment with complement factor C5a receptor antagonist completely abolished ch14.18-induced allodynia. These findings showed that mutant hu14.18 K322 elicited less allodynia than ch14.18 and that ch14.18-elicited allodynia is due to activation of the complement cascade: in part, to formation of membrane attack complex, but more importantly to release of complement factor C5a. Development of immunotherapeutic agents with decreased complement-dependent lysis while maintaining cellular cytotoxicity may offer treatment options with reduced adverse side effects, thereby allowing dose escalation of therapeutic antibodies.
Holographic conductivity of zero temperature superconductors
2010-02-21

Using the recently found by G. Horowitz and M. Roberts (arXiv:0908.3677)\\nnumerical model of the ground state of holographic superconductors (at zero\\ntemperature), we calculate the conductivity for such models. The universal\\nrelation connecting conductivity with the reflection coefficient was used for\\nfinding the conductivity by the WKB approach. The dependence of the\\nconductivity on the frequency and charge density is discussed. Numerical\\ncalculations confirm the general arguments of (arXiv:0908.3677) in favor of\\nnon-zero conductivity even at zero temperature. In addition to the\\nHorowitz-Roberts solution we have found (probably infinite) set of extra\\nsolutions which are normalizable and reach the same correct RN-AdS asymptotic\\nat spatial infinity. These extra solutions (which correspond to larger values\\nof the grand canonical potential) lead to effective potentials that also vanish\\nat the horizon and thus correspond to a non-zero conductivity at zero\\ntemperature.\\n
A prospective study of mechanical physiotherapy for lumbar disk prolapse: Five year follow-up and final report
2010-02-21

Pain centralization during the first 5 treatment sessions of mechanical physiotherapy is a useful diagnostic tool to predict a good longterm outcome. Mechanical physiotherapy with end range spinal movements and leg movements is an effective treatment strategy for many patients with lumbar disk disease.
New Atheism and Old Christianity More Majorum Atheist Delusions. The Christian Revolution and Its Fashionable Enemies – By David Bentley Hart
2010-02-21

Abstract David Bentley Hart has challenged the New Atheism with a careful book about the stirring history of Christianity and its vast gifts to occidental culture: the founding of the person and something Hart titles ‘total humanism’. With ease and exactitude, he defends Christianity with historical tools in claiming that the faith is neither inherently violent nor attempted to destroy antique literature. Against its critics, Hart further holds that Christianity was not inimical to the development of natural science, but rather enabled its progress by steering it to practical, human‐oriented purposes. The argument of the book then takes a polemic turn in fearing the decay of this total humanism in an age of secularism. In the following review essay, I attempt to outline some of the main arguments of Hart's praiseworthy book before suggesting that the Christian ‘revolution’ might be better characterized as a renewal of antiquity. A less revolutionary tale of Christianity is one of a slow and liberal amalgamation of the finest wisdom and truest beliefs from the past and pristine worlds of Melchizedek, Akhenaten or Artaxerxes.
Reduced Basal Autophagy and Impaired Mitochondrial Dynamics Due to Loss of Parkinson's Disease-Associated Protein DJ-1
2010-02-22

We show that loss of DJ-1 leads to impaired autophagy and accumulation of dysfunctional mitochondria that under physiological conditions would be compensated via lysosomal clearance. Our study provides evidence for a critical role of DJ-1 in mitochondrial homeostasis by connecting basal autophagy and mitochondrial integrity in Parkinson's disease.