449 research outputs found
Null fields in the outer Jovian magnetosphere: Ulysses observations
This paper reports on a magnetic field phenomenon, hereafter referred to as null fields, which were discovered during the inbound pass of the recent flyby of Jupiter by the Ulysses spacecraft. These null fields which were observed in the outer dayside magnetosphere are characterised by brief but sharp decreases of the field magnitude to values less than 1 nT. The nulls are distinguished from the current sheet signatures characteristic of the middle magnetosphere by the fact that the field does not reverse across the event. A field configuration is suggested that accounts for the observed features of the events
Distances from the Correlation between Galaxy Luminosities and Rotation Rates
A large luminosity--linewidth template sample is now available, improved
absorption corrections have been derived, and there are a statistically
significant number of galaxies with well determined distances to supply the
zero point. A revised estimate of the Hubble Constant is H_0=77 +-4 km/s/Mpc
where the error is the 95% probability statistical error. Systematic
uncertainties are potentially twice as large.Comment: 21 pages, 9 figures. Invited chapter for the book `Post-Hipparcos
Cosmic Candles', Eds. F. Caputo and A. Heck (Kluwer Academic Publishers,
Dordrecht
Defecting or not defecting: how to "read" human behavior during cooperative games by EEG measurements
Understanding the neural mechanisms responsible for human social interactions
is difficult, since the brain activities of two or more individuals have to be
examined simultaneously and correlated with the observed social patterns. We
introduce the concept of hyper-brain network, a connectivity pattern
representing at once the information flow among the cortical regions of a
single brain as well as the relations among the areas of two distinct brains.
Graph analysis of hyper-brain networks constructed from the EEG scanning of 26
couples of individuals playing the Iterated Prisoner's Dilemma reveals the
possibility to predict non-cooperative interactions during the decision-making
phase. The hyper-brain networks of two-defector couples have significantly less
inter-brain links and overall higher modularity - i.e. the tendency to form two
separate subgraphs - than couples playing cooperative or tit-for-tat
strategies. The decision to defect can be "read" in advance by evaluating the
changes of connectivity pattern in the hyper-brain network
High-dose chemotherapy and peripheral blood stem cell support in refractory gestational trophoblastic neoplasia
We present retrospectively our experience in the use of high-dose chemotherapy and haematopoietic stem cell support (HSCS) for refractory gestational trophoblastic neoplasia (GTN) in the largest series so far reported. In all, 11 patients have been treated at three Trophoblast Centres between 1993 and 2004. The conditioning regimens comprised either Carbop-EC-T (carboplatin, etoposide, cyclophosphamide, paclitaxel and prednisolone) or CEM (carboplatin, etoposide and melphalan) or ICE (ifosfamide, carboplatin, etoposide). Two patients had complete human chorionic gonadotrophin responses, one for 4 and the other for 12 months. Three patients had partial tumour marker responses for 1–2 months. High-dose chemotherapy and HSCS for GTN is still unproven. Further studies are needed, perhaps in high-risk patients who fail their first salvage treatment
Functional, Non-Clonal IgMa-Restricted B Cell Receptor Interactions with the HIV-1 Envelope gp41 Membrane Proximal External Region
The membrane proximal external region (MPER) of HIV-1 gp41 has several features that make it an attractive antibody-based vaccine target, but eliciting an effective gp41 MPER-specific protective antibody response remains elusive. One fundamental issue is whether the failure to make gp41 MPER-specific broadly neutralizing antibodies like 2F5 and 4E10 is due to structural constraints with the gp41 MPER, or alternatively, if gp41 MPER epitope-specific B cells are lost to immunological tolerance. An equally important question is how B cells interact with, and respond to, the gp41 MPER epitope, including whether they engage this epitope in a non-canonical manner i.e., by non-paratopic recognition via B cell receptors (BCR). To begin understanding how B cells engage the gp41 MPER, we characterized B cell-gp41 MPER interactions in BALB/c and C57BL/6 mice. Surprisingly, we found that a significant (∼7%) fraction of splenic B cells from BALB/c, but not C57BL/6 mice, bound the gp41 MPER via their BCRs. This strain-specific binding was concentrated in IgMhi subsets, including marginal zone and peritoneal B1 B cells, and correlated with enriched fractions (∼15%) of gp41 MPER-specific IgM secreted by in vitro-activated splenic B cells. Analysis of Igha (BALB/c) and Ighb (C57BL/6) congenic mice demonstrated that gp41 MPER binding was controlled by determinants of the Igha locus. Mapping of MPER gp41 interactions with IgMa identified MPER residues distinct from those to which mAb 2F5 binds and demonstrated the requirement of Fc CH regions. Importantly, gp41 MPER ligation produced detectable BCR-proximal signaling events, suggesting that interactions between gp41 MPER and IgMa determinants may elicit partial B cell activation. These data suggest that low avidity, non-paratopic interactions between the gp41 MPER and membrane Ig on naïve B cells may interfere with or divert bnAb responses
Artemisinin Attenuates Lipopolysaccharide-Stimulated Proinflammatory Responses by Inhibiting NF-κB Pathway in Microglia Cells
Microglial activation plays an important role in neuroinflammation, which contributes to neuronal damage, and inhibition of microglial activation may have therapeutic benefits that could alleviate the progression of neurodegeneration. Recent studies have indicated that the antimalarial agent artemisinin has the ability to inhibit NF-κB activation. In this study, the inhibitory effects of artemisinin on the production of proinflammatory mediators were investigated in lipopolysaccharide (LPS)-stimulated primary microglia. Our results show that artemisinin significantly inhibited LPS-induced production of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1) and nitric oxide (NO). Artemisinin significantly decreased both the mRNA and the protein levels of these pro-inflammatory cytokines and inducible nitric oxide synthase (iNOS) and increased the protein levels of IκB-α, which forms a cytoplasmic inactive complex with the p65-p50 heterodimeric complex. Artemisinin treatment significantly inhibited basal and LPS-induced migration of BV-2 microglia. Electrophoretic mobility shift assays revealed increased NF-κB binding activity in LPS-stimulated primary microglia, and this increase could be prevented by artemisinin. The inhibitory effects of artemisinin on LPS-stimulated microglia were blocked after IκB-α was silenced with IκB-α siRNA. Our results suggest that artemisinin is able to inhibit neuroinflammation by interfering with NF-κB signaling. The data provide direct evidence of the potential application of artemisinin for the treatment of neuroinflammatory diseases
Management in non-traumatic arm, neck and shoulder complaints: differences between diagnostic groups
Arm, neck and/or shoulder complaints are common in western societies. In the Netherlands, general practice guidelines are issued on shoulder pain and epicondylitis only. Little is known about actual management of the total range of diagnoses. The objectives of the study are: to determine management in patients consulting the GP with a new episode of non-traumatic arm neck and shoulder complaints up to 6 months after the first consultation. To evaluate differences in management between patients with specific diagnoses versus non-specific diagnoses and between specific diagnostic groups. In a prospective cohort study in general practice. We recruited 682 eligible patients. Data on diagnosis, management, patient- and complaint-characteristics were collected. Co-occurrence of treatment options was presented in scaled rectangles. After 6 months, additional diagnostic tests had been performed in 18% of the patients, mainly radiographic examination (14%). Further, 49% had been referred for physiotherapy and 12% to the medical specialist. Patients with specific diagnoses were more frequently referred for specialist treatment, and patients with non-specific diagnoses for physiotherapy. Corticosteroid injections (17%) were mainly applied specific diagnoses (e.g. impingement syndrome, frozen shoulder, carpal tunnel and M. Quervain). Frequencies of prescribed medication (51%) did not differ between specific and non-specific
How do religious norms diffuse? Institutional translation and international change in a post-secular world society
This article draws from Habermasian post-secular theory to broaden the scope of Constructivist research on norm dynamics beyond its current Western-centric focus. In an increasingly post-secular world society, we conceptualize the mechanism of institutional translation to explain processes of norm diffusion whereby culturally situated ‘thick’ norms acquire a ‘thinner’ ethical status via a dialogical process of normative contestation across diverse ethical perspectives. Institutional translation differs from, but also complements, mechanisms of norm diffusion, such as persuasion and localization, by illustrating how norms conceived and promoted by non-Western religious-based actors can acquire global legitimacy within the institutions of the international liberal order. The article investigates the explanatory value of this framework through an empirical analysis of two contrasting cases of norm promotion by the Organization of Islamic Conference at the United Nations. The first case considers the global diffusion of the norm of dialogue of civilizations as an example of successful institutional translation. The second case illustrates the failed diffusion of the norm against th
Association between -T786C NOS3 polymorphism and resistant hypertension: a prospective cohort study
<p>Abstract</p> <p>Background</p> <p>It is estimated that 5% of the hypertensive patients are resistant to conventional antihypertensive therapy. Polymorphisms in the endothelial nitric oxide synthase (NOS3) gene have been associated with high blood pressure levels, but not with resistant hypertension. The aim of the present study was to investigate if the -786T>C and G894T (Glu298Asp) polymorphisms of the NOS3 gene were associated with resistant hypertension.</p> <p>Methods</p> <p>A prospective case-control observational study was performed. From a series of 950 consecutive patients followed up during 42 months, 48 patients with resistant hypertension were detected. 232 patients with controlled high blood pressure were also included.</p> <p>Results</p> <p>No differences were observed in the distribution of G894T (Glu298Asp) NOS3 genotypes between the resistant hypertension group and the controlled hypertension patients. However, genotype -786CC was more frequent in the group of patients with resistant hypertension (33.3%) than in the group of patients with controlled high blood pressure (17.7%) (p 0.03). Furthermore carriers of allele T (-786TC and -786TT) were more frequent in patients with controlled hypertension (82.3%) than those with resistant hypertension (66.7%) (Multivariate analysis; RR 2.09; 95% CI 1.03–4.24; p 0.004).</p> <p>Conclusion</p> <p>Our results indicate that genotype -786CC of the NOS3 gene increase the susceptibility to suffer resistant hypertension, which suggest that resistance to conventional therapy could be determined at the endothelial level.</p
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