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We present the first galactic-scale model of the gas dynamics of the prototype barred Seyfert 1 galaxy NGC 1097. We use large-scale FaNTOmM Fabry-Perot interferometric data covering the entire galactic disc and combine the distribution and kinematics maps with high-resolution two-dimensional spectroscopy from the Gemini telescope. We build a dynamical model for the gravitational potential by applying the analytic solution to the equations of motion, within the epicyclic approximation. Our model reproduces all the significant kinematic and structural signatures of this galaxy. We find that the primary bar is 7.9 ± 0.6 kpc long and has a pattern speed of 36 ± 2 km s−1 kpc−1. This places the corotation radius at 8.6 ± 0.5 kpc, the outer Lindblad resonance at 14.9 ± 0.9 kpc and two inner Lindblad resonances at 60 ± 5 pc and 2.9 ± 0.1 kpc. These derivations lead to a ratio of the corotation radius over bar length of 1.0–1.2, which is in agreement with the predictions of simulations for fast galaxy bars. Our model presents evidence that the circumnuclear ring in this galaxy is not located near any of the resonance radii in this galaxy. The ring might have once formed at the outer inner Lindblad resonance radius, and it has been migrating inwards, towards the centre of the galactic gravitational potential. [ABSTRACT FROM AUTHOR]

Rac1 has a role in proliferation and survival of tumor cells in vitro. The exact effects of Rac1 on growth, apoptosis and corresponding signaling pathways during tumorigenesis in vivo, however, have not been explored yet. Using mice with a keratinocyte-restricted deletion of the Rac1 gene, we found that Rac1 is essential for DMBA/TPA-induced skin tumor formation. This corresponded to a decreased keratinocyte hyperproliferation, although apoptosis was not detectably altered. Activated Rac1 promoted Erk-dependent hyperproliferation by Pak1-mediated Mek activation independent of Mek1 phosporylation at serine 298. Rac1 was furthermore required for Pak2-dependent hyperactivation of Akt, which under in vivo condition was restricted to the suprabasal cell layers corresponding to a suprabasal-specific expression of Pak2. It is surprising that none of these signaling pathways was altered in untreated Rac1-deficient skin, indicating a hyperproliferation-specific function of Rac1 in vivo. These data suggest that blocking of Rac1 function might allow tumor-specific growth repression, as Rac1 is not required for normal growth and growth signaling controlling pathways in skin in vivo. [ABSTRACT FROM AUTHOR]

Abstract: Malignant tumor cells display uncontrolled proliferation, loss of epithelial cell polarity, altered interactions with neighboring cells and the surrounding extracellular matrix, and enhanced migratory properties. Proteins of the Rho GTPase family regulate all these processes in cell culture and, for that reason, Rho GTPases, their regulators, and their effectors have been suggested to control tumor formation and progression in humans. However, while the tumor-relevant functions of Rho GTPases are very well documented in vitro, we are only now beginning to assess their contribution to cancer in human patients and in animal models. This review will give a very brief overview of Rho GTPase function in general and then focus on in vivo evidence for a role of Rho GTPases in malignant tumors, both in human patients and in genetically modified mice. [Copyright &y& Elsevier]

There is growing evidence implicating dysfunctional glutamatergic neurotransmission and abnormal interactions between the glutamate and dopamine (DA) systems in the pathophysiology of various neuropsychiatric disorders including schizophrenia. The present study evaluated knockout (KO) mice lacking the L-α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) GluR1 receptor subunit for a range of behaviors considered relevant to certain symptoms of schizophrenia. KO showed locomotor hyperactivity during exposure to open field and in response to a novel object, but normal activity in a familiar home cage. Open field locomotor hyperactivity in KO was effectively normalized to WT levels by treatment with the DA antagonist and neuroleptic haloperidol, while locomotor stimulant effects of the NMDA receptor antagonist MK-801 were absent in KO. Social behaviors during a dyadic conspecific encounter were disorganized in KO. KO showed deficits in prepulse inhibition of the acoustic startle response. In vivo chronoamperometric measurement of extracellular DA clearance in striatum demonstrated retarded clearance in KO. These data demonstrate behavioral abnormalities potentially pertinent to schizophrenia in GluR1 KO, together with evidence of dysregulated DA function. Present findings provide novel insight into the potential role of GluR1, AMPA receptors and glutamate × DA interactions in the pathophysiology of schizophrenia and other neuropsychiatric conditions.Molecular Psychiatry (2008) 13, 631–640; doi:10.1038/sj.mp.4002056; published online 7 August 2007 [ABSTRACT FROM AUTHOR]

A technique based on Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance (FTIR-ATR) was developed and used to study movement of water into bitumen/substrate interfaces, as well as to characterize stripping. Bitumens from different sources were used and applied on various substrates (silicon, germanium and zinc selenide) as thin films. The influence of bitumen type, substrate type, temperature, film thickness and modification with amines, on water damage was studied. The technique gave information on water flow into interfaces and how stripping possibly occurs. It distinguished between stripping and non-stripping bitumens. At least one of three processes occurred, namely water diffusion, film fracture, and bitumen displacement by water, respectively. The diffusion of water did not obey Fick’s law. Stripping was influenced by bitumen source when silicon and germanium substrates were used. Notching the films made the process of water entry almost occur immediately. Additives significantly reduced stripping in the moisture-sensitive bitumen on silicon and germanium substrates, even after film notching. Although, good agreement was observed between tests for the bitumens that did not strip, the tests on stripping bitumens showed poor agreement. [ABSTRACT FROM AUTHOR]

Objectives: To measure the coverage, gender distribution, and participants' prevalence of genital Chlamydia trachomatis infections using a new Internet based self selective testing approach by means of home sampling in the general population in Sweden. To investigate factors associated with these measures. Methods: Observational survey of people actively ordering coded testing packages, and checking their test results, from a known website. No personal invitations were sent out. All inhabitants (256 885 men and women) in a Swedish county were eligible to participate. A special interest was taken in coverage, gender distribution, participants' chlamydia prevalence, and determinants for infection. Results: Testing was highest in the age group 20-24 years, where 298/9495 (3.1%) of all women and 171/9574 (1.8%) of all men in the population participated. The overall population participation (all ages) was 906/256 885 (0.4%). 40% (364/906) of the tests were from men and 60% (542/906) from women. The prevalence of Chlamydia trachomatis infection was 6.0% (95% Cl: 3.6% to 8.4%) among male participants and 4.6% (95% CI: 2.8% to 6.4%) among female participants. Prevalence increased with decreasing age. Believing to be infected and having symptoms were the strongest determinants of infection. Conclusion: Simplifying and increasing the accessibility of chlamydia testing by means of internet and home sampling proved feasible. Self risk assessment improves the chance of finding people infected by Chlamydia trachomatis, especially among men, if an accessible testing method is offered. This new method can serve as a supplement to regular preventive methods and might encourage young people to be tested. [ABSTRACT FROM AUTHOR]

The progression of human immunodeficiency virus (HIV) disease and plasma levels of HIV may differ between racial groups. We compared HIV-specific T cell responses between vertically HIV-1-infected Hispanic and African American children. Subjects were matched for sex, age, viral load, and CD4+ cell count in 18 pairs; T cell responses were measured by cytokine-enhanced interferon-γ assay. Peripheral blood mononuclear cells were stimulated with HIV consensus peptides from Gag, Nef, and Tat. The influence of ethnicity, sex, age, viral load, and CD4+ cell count on T cell responses was determined through linear regression analyses. After adjustment for CD4+ count, age, and log10 viral load, African American children demonstrated significantly higher Gag responses (average, 486 spot-forming cells higher; P = .01) than Hispanic children; this was significantly driven by robust responses in African American girls near the age of puberty, many of whom carried the human leukocyte antigen class I B*58 allele. [ABSTRACT FROM AUTHOR]

The enzyme-linked immunospot (ELISPOT) assay is a highly sensitive and reproducible method for quantifying T cell-mediated immune responses, and has been used to measure antigen-specific responses post-vaccination. While there are several advantages of the ELISPOT assay for use in field settings for large-scale vaccination trials, blood draw volumes are often limited, and the number of antigen-specific responses that can be measured is constrained by the limited cell number. We reasoned that it should be possible to salvage and rescue viable cells from a completed ELISPOT assay post-incubation, to use for further experimentation. Here, we show that cells rescued from an ELISPOT plate after assay are viable, and may be used in a second cytokine-producing assay, in a proliferation assay, or to provide a source of DNA for genetic studies such as human leukocyte antigen (HLA) typing. Rescue of cells after an ELISPOT assay will be particularly useful for increasing sample utility and maximizing data collection from T cell assays in vaccine trials. [Copyright &y& Elsevier]

The ELISPOT assay is a specific, sensitive, quantitative assay for assessing cell-mediated immune responses to a variety of antigens including HIV-1 peptides. In an interferon (IFN)-γ-ELISPOT assay, peripheral blood mononuclear cells (PBMC) from two HIV-1 exposed seronegative (ESN) individuals appeared to respond strongly to an HIV Gag peptide. Analysis of this peptide revealed that it was incompletely dissolved and induced non-specific spot formation, even in the absence of cells. In subsequent experiments, the peptide was found to interact with avidin and the ELISPOT membrane. Filtering the peptide prevented non-specific spot formation. These findings underscore the need for appropriate controls and proper peptide preparation in order to reduce the risk of false-positive ELISPOT responses. [Copyright &y& Elsevier]

Performance of recycled asphalt pavements depends, among other things, on the degree of mixing of old and new binders. One of the factors contributing to the mixing is diffusion, which increases the homogeneity of recycled binders. In this study, FTIR-ATR (Fourier Transform Infrared Spectroscopy with Attenuated Total Reflectance) has been applied to investigate influence of temperature, viscosity of the diffusion medium, and diffusant size and polarity on diffusion characteristics. Several substances, referred to as markers, have been monitored when diffusing through different binders. By careful selection of markers, the importance of diffusant size and polarity on rate of diffusion has been demonstrated. Diffusion has been modelled using Stoke-Einstein's equation and compared with experimental data obtained by FTIR-ATR. The equation has shown useful in explaining the effects of temperature, viscosity and molecular size on diffusion. [ABSTRACT FROM AUTHOR]

Dehydroepiandrosterone sulfate (DHEAS), which is of almost exclusive adrenal origin, is important for the androgen status in women and prepubertal children, and DHEAS assays are used in the investigation of hyperandrogenism. There are conflicting reports concerning a diurnal variation in serum DHEAS. Although of adrenocortical origin, serum DHEAS levels are decreased by oral contraceptives (OCs). DHEAS is strongly bound to serum albumin and has a very low metabolic clearance rate. The present study was performed in order to investigate whether a diurnal variation in serum DHEAS exists and, if so, whether this diurnal variation and the decreased DHEAS levels following OC use are related to alterations in adrenocortical steroids or to changes in serum albumin. Serum concentrations of DHEAS, dehydroepiandrosterone (DHEA), cortisol and albumin were determined in blood samples taken every half hour over a 24-h period in 10 healthy women before and during use of combined OCs. Significant and frequently synchronous diurnal variations in serum DHEAS and albumin were found before as well as during OC use. These variations were not synchronous with the diurnal variation in DHEA. OCs significantly decreased serum DHEAS and albumin levels. A multiple regression analysis showed changes in albumin to be the most decisive factor for the diurnal variation as and for OC-induced changes in DHEAS. Changes in serum DHEAS during the day and following OC use are related to alterations in its main binding protein, serum albumin, rather than to changes in adrenocortical steroid secretion. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the associations between risk behaviour and women's reported sexually transmitted diseases (STDs). All the women aged 19, 21, 23 and 25, residing in a specified housing area, were invited to answer a questionnaire regarding their sexual behaviour, smoking and alcohol consumption and previous history of STD. Of the 611 women participating, one out of 4 women had a history of at least one STD. In an univariate analysis, self-reported STD was found to be related to age, having more than 4 lifetime sexual partners, having practised intercourse at first date, inconsistent use of condoms, alcohol consumption of more than 3 bottles of wine per month and smoking. These factors were, however, not independent of each other and when subjected to a multivariate logistic regression analysis 2 factors, i.e. the lifetime number of sexual partners (more than 4 partners vs one; OR 7.94, (3.41-18.50)) and coitus on first date (practised more than once vs never, OR 2.99 (1.55-5.78)) emerged as independently associated with a previous STD. [ABSTRACT FROM AUTHOR]

This double-blind immunotherapy trial in children, using a purified and standardized Cladosporium herbarium preparation, has shown that children with mould asthma and/or rhinoconjunctivitis, responded to immunotherapy with a decrease in specific IgE and a significant increase in specific IgG. There was a marked increase in the ratio specific IgG/specific IgE as a result of active treatment, IgE-CRIE radiostaining patterns showed no pronounced changes after 10 months' actives treatment and no "new sensitivities" could be detected in the studied patients. IgG-CRIE radiostaining, primarily directed towards the important allergens, was significantly increased in the active group and particularly towards Ag-12 (partially identical to a previously described major allergen in Cladosporium herbarium, Ag-54). Children treated with histamine placebo showed no change in antibody patterns during 10 months of treatment. [ABSTRACT FROM AUTHOR]