188 research outputs found
Prevalence of and Some Factors Relating with Unwanted Pregnancy, in Ahwaz City, Iran, 2010
We aimed to find the
prevalence and some factors relating with unwanted
pregnancy. Methods. It was a
cross-sectional study on 400 randomly pregnant
women, who were referring to different health
centers in Ahwaz city during 2010. Data was
conducted based on questionnaire, and all the
analysis was performed using SPSS (version 17)
statistical analysis software.
Results. The prevalence of
unwanted pregnancy was 26%. The percentage of
unwanted pregnancy in ages more than 35 years was
approximately three times more than the intended
pregnancy. There were significant relationship
between unwanted pregnancy and some variables such
as age, number of pregnancy, number of childbirth,
education status, economic status, husband's
occupation, and the relationship with the spouse
and contraceptive methods (P < 0.0001). Conclusion. The
prevalence of unwanted pregnancy was high. To
prevent unwanted pregnancy using consultation
services before planning to be pregnancy, it is
necessary to identify the factors relating
with unwanted pregnancy
Various methods of simulating wave kinematics on the structural members of 100-year responses
The main force acting on an offshore structure is usually due to wind-generated random waves. According to the Morison equation, the wave force on a cylindrical member of an offshore structure depends on wave kinematics at the centre of the element. It is therefore essential to accurately estimate the magnitude of wave-induced water particle kinematics at all points in a random wave field. Linear random wave theory (LRWT) is the most-frequently used theory to simulate water particle kinematics at different nodes of an offshore structure. Several empirical techniques have been suggested to provide a more realistic representation of the near-surface wave kinematics. The empirical techniques popular in the offshore industry include Wheeler stretching and vertical stretching. Most recently, two new effective methods (effective node elevation and the effective water depth) have been recently introduced. The problem is that these modified methods differ from one another in their predictions. Hence, the aim of this study is to investigate the effects of predicting the 100-year responses from various methods of simulating wave kinematics accounting for the current effect. In this paper, four versions of the wave kinematics procedure have been tested by comparing the short-term probability distributions of extreme responses. For all current cases, the highest vertical ratios for zero, positive and negative current cases are 1.414, 1.175 and 1.831, respectively. It is observed that even for positive-current cases, the difference between Wheeler and vertical stretching predictions is quite high and cannot be neglected. Thus, further investigation is necessary to resolve this problem and the outcomes in providing useful design information for the oil and gas industry
Cooling dynamics of carbon cluster anions
A series of ion storage experiments on small carbon cluster anions was conducted to understand size-dependent cooling processes. The laser-induced delayed electron detachment time profile show clear even/odd alternation due to the presence of the electronic cooling. The time evolution of the internal energy distribution was simulated for Cn- (n=4 to 7) with a common procedure taking vibrational and electronic cooling into account
OR.107. TIM-1 Plays a Crucial Role in the Expansion of Autopathogneic T-Cells and Regulation of Autoimmunity [abstract only]
T-cell immunoglobulin and mucin (TIM) family Members are differentially expressed on Th1 and Th2 cells. Polymorphisms of TIM-1 have been associated with susceptibility to asthma; however, its role in regulating autoimmunity has not been studied. Here, we have used an agonistic antiTIM-1 antibody (Ab, Clone 3B3) which has previously been shown to costimulate T-cell activation and expansion, to analyze the role of TIM-1 in the development and regulation of experimental autoimmune encephalomyelitis (EAE). Treatment with 3B3 dramatically enhances the severity of EAE as well as the frequency of encephalitogenic CD4+ T-cells and the production of IFN-g and IL-17 by these cells. Furthermore, administration of 3B3 breaks self-tolerance and induces EAE in the disease resistant B10.S strain. We have utilized another anti-TIM-1 Ab (RMT1-10) that does not costimulate T-cell activation in vitro. In contrast to 3B3, treatment with RMT1-10 inhibits the development of EAE and reduces the frequency of encephalitogenic CD4+ T-cells with a commensurate decrease in the production of IFN-g and IL-17. Treatment with RMT1-10 causes CD4+ T-cells to produce more IL-4 and IL-10. We provide evidence that both 3B3 and RMT1-10 bind to the same epitope in the Ig domain of TIM-1, but the binding affinity of 3B3 is much higher than that of RMT1-10. These data suggest that TIM-1 engagement with the agonistic Ab, along with TcR ligation, costimulates T-cell expansion with pro-inflammatory IFN-g and IL-17 production resulting in the breakdown of self-tolerance and development of autoimmunity, whereas blocking anti-TIM-1 Ab causes a decrease in the autopathogenic Th1/ThIL-17 responses. This study demonstrates that TIM-1 is a key cell surface molecule that regulates effector T-cell response and depending on hopw the molecule is engaged, autoimmune responses can be either enhanced or inhibited in vivo
Differential engagement of Tim-1 during activation can positively or negatively costimulate T cell expansion and effector function
It has been suggested that T cell immunoglobulin mucin (Tim)-1 expressed on T cells serves to positively costimulate T cell responses. However, crosslinking of Tim-1 by its ligand Tim-4 resulted in either activation or inhibition of T cell responses, thus raising the issue of whether Tim-1 can have a dual function as a costimulator. To resolve this issue, we tested a series of monoclonal antibodies specific for Tim-1 and identified two antibodies that showed opposite functional effects. One antiβTim-1 antibody increased the frequency of antigen-specific T cells, the production of the proinflammatory cytokines IFN-Ξ³ and IL-17, and the severity of experimental autoimmune encephalomyelitis. In contrast, another antiβTim-1 antibody inhibited the generation of antigen-specific T cells, production of IFN-Ξ³ and IL-17, and development of autoimmunity, and it caused a strong Th2 response. Both antibodies bound to closely related epitopes in the IgV domain of the Tim-1 molecule, but the activating antibody had an avidity for Tim-1 that was 17 times higher than the inhibitory antibody. Although both antiβTim-1 antibodies induced CD3 capping, only the activating antibody caused strong cytoskeletal reorganization and motility. These data indicate that Tim-1 regulates T cell responses and that Tim-1 engagement can alter T cell function depending on the affinity/avidity with which it is engaged
Offshore structural reliability assessment by probabilistic proceduresβa review
Offshore installations must be built to resist fatigue as well as extreme forces caused by severe environmental conditions. The structural reliability analysis is the popular practise to assess a variety of natural waves determined by the longβterm probability distribution of wave heights and corresponding periods on the site. In truth, however, these structures are subjected to arbitrary waveβinduced forces in the open ocean. Hence, it is much more reasonable to account for the changed loading characteristics by determining the probabilistic characteristics of the random loads and outcomes responses. The key challenges are uncertainties and the nonβlinearity of Morisonβs drag element, which results in nonβGaussian loading and response distributions. This study would analyze advances achieved to date in a comprehensive probabilistic review of offshore fixed jacket-type platforms
Radiative cooling of carbon cluster anions C2n+1β (n = 3β5)
Radiative cooling of carbon cluster anions C2n+1β (n = 3β5) is investigated using the cryogenic electrostatic ion storage ring DESIREE. Two different strategies are applied to infer infrared emission on slow (milliseconds to seconds) and ultraslow (seconds to minutes) timescales. Initial cooling of the ions over the millisecond timescale is probed indirectly by monitoring the decay in the yield of spontaneous neutralization by thermionic emission. The observed cooling rates are consistent with a statistical model of thermionic electron emission in competition with infrared photon emission due to vibrational de-excitation. Slower cooling over the seconds to minutes timescale associated with infrared emission from low-frequency vibrational modes is probed using time-dependent action spectroscopy. For C9β and C11β, cooling is evidenced by the time-evolution of the yield of photo-induced neutralization following resonant excitation of electronic transitions near the detachment threshold. The cross-section for resonant photo-excitation is at least two orders of magnitude greater than for direct photodetachment. In contrast, C7β lacks electronic transitions near the detachment threshold
Receptor-Mediated Endocytosis of Ξ±-Galactosidase A in Human Podocytes in Fabry Disease
Injury to the glomerular podocyte is a key mechanism in human glomerular disease and podocyte repair is an important therapeutic target. In Fabry disease, podocyte injury is caused by the intracellular accumulation of globotriaosylceramide. This study identifies in the human podocyte three endocytic receptors, mannose 6-phosphate/insulin-like growth II receptor, megalin, and sortilin and demonstrates their drug delivery capabilities for enzyme replacement therapy. Sortilin, a novel Ξ±-galactosidase A binding protein, reveals a predominant intracellular expression but also surface expression in the podocyte. The present study provides the rationale for the renal effect of treatment with Ξ±-galactosidase A and identifies potential pathways for future non-carbohydrate based drug delivery to the kidney podocyte and other potential affected organs
Acarbose versus trans-chalcone: comparing the effect of two glycosidase inhibitors on obese mice
Streptococcus pneumoniae Serotype 1 Capsular Polysaccharide Induces CD8+CD28β Regulatory T Lymphocytes by TCR Crosslinking
Zwitterionic capsular polysaccharides (ZPS) of commensal bacteria are characterized by having both positive and negative charged substituents on each repeating unit of a highly repetitive structure that has an Ξ±-helix configuration. In this paper we look at the immune response of CD8+ T cells to ZPSs. Intraperitoneal application of the ZPS Sp1 from Streptococcus pneumoniae serotype 1 induces CD8+CD28β T cells in the spleen and peritoneal cavity of WT mice. However, chemically modified Sp1 (mSp1) without the positive charge and resembling common negatively charged polysaccharides fails to induce CD8+CD28β T lymphocytes. The Sp1-induced CD8+CD28β T lymphocytes are CD122lowCTLA-4+CD39+. They synthesize IL-10 and TGF-Ξ². The Sp1-induced CD8+CD28β T cells exhibit immunosuppressive properties on CD4+ T cells in vivo and in vitro. Experimental approaches to elucidate the mechanism of CD8+ T cell activation by Sp1 demonstrate in a dimeric MHC class I-Ig model that Sp1 induces CD8+ T cell activation by enhancing crosslinking of TCR. The expansion of CD8+CD28β T cells is independent, of direct antigen-presenting cell/T cell contact and, to the specificity of the T cell receptor (TCR). In CD8+CD28β T cells, Sp1 enhances Zap-70 phosphorylation and increasingly involves NF-ΞΊB which ultimately results in protection versus apoptosis and cell death and promotes survival and accumulation of the CD8+CD28β population. This is the first description of a naturally occurring bacterial antigen that is able to induce suppressive CD8+CD28β T lymphocytes in vivo and in vitro. The underlying mechanism of CD8+ T cell activation appears to rely on enhanced TCR crosslinking. The data provides evidence that ZPS of commensal bacteria play an important role in peripheral tolerance mechanisms and the maintenance of the homeostasis of the immune system
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