Delayed-type hypersensitivity

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Inhibition of cystathionine-γ-lyase controls interleukin-12 production by dendritic cells, delayed-type hypersensitivity and transplant rejection

Inhibition of cystathionine-γ-lyase controls interleukin-12 production by dendritic cells, delayed-type hypersensitivity and transplant rejection

NFkB or H 2 S production, but could be assigned to a modulation of intracellular cysteine content. Conclusion Our results identify CSE as a novel factor that plays a cri- tical role in IL-12 production by monocytes and DCs by modulating intracellular cysteine levels, which in turn controls Th-1 type immune responses.

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Pathogenesis and diagnosis of delayed-type drug hypersensitivity reactions, from bedside to bench and back

Pathogenesis and diagnosis of delayed-type drug hypersensitivity reactions, from bedside to bench and back

Drug hypersensitivity reactions (DHR) have been present since the advent of drugs. In particular T-cell mediated delayed-type hypersensitivity reactions represent a heterogeneous clinical entity with a diverse pathogenesis and result in a considerable burden of morbidity and mortality not only driven by the reactions themselves but also by the use of alternatives which are sometimes less effective or even more dangerous. Diagnostic procedures rely on clinical history, skin testing and potential provocation testing, whereas validated in vitro diagnostic procedures are still lacking for most of them. Recent work in the field of pharmacogenomics combined with basic scientific research has provided insights in the pathogenesis of abacavir and carbamazepine hypersensitivities linked with certain human leucocyte antigen risk alleles. Nevertheless, important scientific questions on how other DHR arise and how host-drug interactions occur, remain unanswered. Recent work indicates an intricate relation between host, drug and pathogens in severe cutaneous and systemic reactions and provides more insights in the role of regulatory T-cells and viral reac- tivation in these reactions. In this review we focus on type IV delayed-type DHR, and address recent advances in the pathogenesis, pharmacogenomics, and diagnosis of these reactions with an emphasis on the understandings arising from basic research.
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Unusual delayed reaction after H1N1 vaccine.

Unusual delayed reaction after H1N1 vaccine.

Allergic contact dermatitis presented by our colleague come from delayed-type hypersensitivity reaction (7), mediated by hapten-specific T cells (8). Even though T-cell mediated reactions usually starting from 2–8 hours up to 2 days after vaccination (9), very late reactions have been described for other medications [up one month (10) ] . Other differential cause of acute dermatitis has been excluded by anamnesis and patch tests. No cause of immunodeficiency has been found. It is however possible, the lesion appeared before our colleague noticed it, but only a few days before.
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New results for delayed neural field equations

New results for delayed neural field equations

gregory.faye@sophia.inria.fr olivier.faugeras@sophia.inria.fr May 6, 2010 Abstract Neural field models with delays define a useful framework for modeling macroscopic parts of the cortex involving sev- eral populations of neurons. Nonlinear delayed integro- differential equations describe the spatio-temporal behav- ior of these fields. Using methods from the theory of delay differential equations, we show the existence and unique- ness of a solution of these equations. A Lyapunov analysis gives us sufficient conditions for the solutions to be asymp- totically stable. We also present a study of the numerical computation of these solutions in a special case. This is, to our knowledge, the first time that a serious analysis of the problem of the existence and uniqueness of a solution of these equations has been performed. Another original con- tribution of ours is the definition of a Lyapunov functional and the result of stability it implies. We illustrate our work on a variety of examples that are relevant to modeling in neuroscience.
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Delayed-time domain impedance boundary conditions (D-TDIBC)

Delayed-time domain impedance boundary conditions (D-TDIBC)

mesh. 6. Conclusion A novel numerical strategy called Delayed-Time Domain Impedance Boundary Condition (D-TDIBC) has been derived from an existing TDIBC approach [ 1 – 4 ] in order to account for time delays in Navier–Stokes simulation. The method allows to mimic acoustic wave propagation in domains larger than the computational domain used in the numerical study. The benefits are twofold: (1) computational cost can be saved and spatial resolution can focus on areas of interest, (2) any additional length can be added to the computational domain allowing straightforward investigations of geometry changes downstream or upstream of the zone of interest. While the former mainly concerns structured meshes, the latter applies to all types of grids.
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A delayed-choice experiment enabled by entanglement

A delayed-choice experiment enabled by entanglement

By manipulating the corroborative photon polarization state, we demonstrate a continuous morphing of the test photon from wave to particle behaviour. This refutes simple models of single photons behaving exclusively as waves or particles (see FIG. 2) [6]. The state of the QBS is determined via the measurement of the corroborative pho- ton (not shown) only after the test photon has already been detected. The space-like separation between the two mea- surements invalidates local-hidden variable models associ- ated with pre-existing information about the measurement outcomes. In other words, when the test photon is de- tected, no information is available about the type of mea- surement it underwent. These results still perfectly obey Bohr’s complementarity notion and its extension [7].
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Virtual Chimera States for Delayed-Feedback Systems

Virtual Chimera States for Delayed-Feedback Systems

(Dated: July 16, 2013) Time-delayed systems are found to display remarkable temporal patterns which dynamics split into regular and chaotic components repeating at the interval of a delay. This novel long-term behavior for delay dynamics results from strongly asymmetric nonlinear delayed feedback driving a highly damped harmonic oscillator dynamics. In the corresponding virtual space-time representation, the behavior is found to develop as a chimera-like state, a new paradigmatic object from the network theory characterized by co-existence of synchronous and incoherent oscillations. Numerous virtual chimera states are obtained and analyzed, through experiment, theory and simulations.
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Mitotic block and delayed lethality in HeLa epithelial cells exposed to Escherichia coli BM2-1 producing cytotoxic necrotizing factor type 1

Mitotic block and delayed lethality in HeLa epithelial cells exposed to Escherichia coli BM2-1 producing cytotoxic necrotizing factor type 1

If the cytopathic activity is not triggered by the release of a freely diffusible form of toxic activity into the culture medium, then we should admit the existence of a direct mechanism of interaction between bacteria and HeLa cells. In the present study, we have limited our analysis to the role of established adhesins present on strain BM2-1, i.e., type 1 and F1C fimbrial adhesins. Specific inhibition of these adhesins did not signifi- cantly decrease pathogenicity, which seems to rule out any specific contribution of these adhesins in our model. This re- sult could largely be expected, since the standardized experi- mental conditions did not specifically favor the expression of either of these fimbriae (33) and since HeLa cells do not express specific receptors for F1C (23). The role of the so- called loose-adhesion phenotype that was demonstrated in the present study should now be investigated in detail. This adhe- sion was described as loose because, in contrast to the situation with binding mediated by most fimbrial adhesins, bacteria could be removed by repeated washings. However, when fixa- tion was performed before the washings, then binding ap- peared to be both massive and specific for cells. To our knowl- edge, the loose-adhesion phenotype has never explicitly been described before for E. coli, but it has been reported to occur in the initial phase of Salmonella adhesion to epithelial cell surfaces (17).
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Delayed-time domain impedance boundary conditions (D-TDIBC)

Delayed-time domain impedance boundary conditions (D-TDIBC)

mesh. 6. Conclusion A novel numerical strategy called Delayed-Time Domain Impedance Boundary Condition (D-TDIBC) has been derived from an existing TDIBC approach [1–4] in order to account for time delays in Navier–Stokes simulation. The method allows to mimic acoustic wave propagation in domains larger than the computational domain used in the numerical study. The benefits are twofold: (1) computational cost can be saved and spatial resolution can focus on areas of interest, (2) any additional length can be added to the computational domain allowing straightforward investigations of geometry changes downstream or upstream of the zone of interest. While the former mainly concerns structured meshes, the latter applies to all types of grids.
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CD103-mediated regulation of airway hypersensitivity responses to bioaerosol-associated antigens

CD103-mediated regulation of airway hypersensitivity responses to bioaerosol-associated antigens

data suggest that a type IV hypersensitivity response is induced after exposure to low-dose of MSS, although we also observed a low level of allergic, type I hypersensitivity response. Similar to previous studies (3), an exacerbated total response was observed at 100µg MSS compared to 3µg, characterized mainly by macrophages and lymphocytes (Figure 5.2A). Of important note is the inversely proportional presence of eosinophils to the quantity of instilled MSS, as denoted by the higher % of eosinophils response at 3µg MSS compared to 100µg. This is very interesting since the total number of cells is similar after exposure to low or high quantities of MSS (Figure 5.2A). This suggests that different types of hypersensitivity responses can be developed with different levels of MSS exposure, or that the higher dose shifts the timing of the response to include more macrophages at the time of euthanasia. Independently of the explanation, this is an important observation and a significant factor in determining the potential impact of MSS bioaerosols exposure in humans. Additionally, when looking at the effector response, we found that the cell number and % of CD4/IL-13 + T cells are decreased in mice exposed to 100µg compared to 3µg, while the CD4/IL-17A + T cells population remains unchanged (Figure 5.2B). Furthermore, IgG 1 and IgG 2a levels are
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Delayed ileal perforation from sodium polystyrene sulfonate

Delayed ileal perforation from sodium polystyrene sulfonate

Anne-Laure Faucon, Michel Daudon, Vincent Frochot, Dominique Bazin, Benoit Terris, Valérie Caudwell.. To cite this version:.[r]

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A quantum delayed-choice experiment enabled by entanglement

A quantum delayed-choice experiment enabled by entanglement

By manipulating the corroborative photon polarization state, we demonstrate a continuous morphing of the test photon from wave to particle behaviour. This refutes simple models of single photons behaving exclusively as waves or particles (see FIG. 2) [6]. The state of the QBS is determined via the measurement of the corroborative pho- ton (not shown) only after the test photon has already been detected. The space-like separation between the two mea- surements invalidates local-hidden variable models associ- ated with pre-existing information about the measurement outcomes. In other words, when the test photon is de- tected, no information is available about the type of mea- surement it underwent. These results still perfectly obey Bohr’s complementarity notion and its extension [7].
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Delayed Hemolytic Transfusion Reaction in Sickle Cell Disease

Delayed Hemolytic Transfusion Reaction in Sickle Cell Disease

temporary state of “pseudo”-autoimmunity. Although originally described as a type of he mo lysis of autologous cells, the concept of bystander immune cytolysis has been e xtended to include other instances in which immune destruction of cells is caused by antibody that is not developed in response to intrinsic antigens on the cell being lysed. Bystander hemolysis during DHTR may occur following activation of co mple ment as a result of the reaction of alloantibodies with transfused RBCs or other antibody reactions with transfused foreign antigens, leading to the attachment o f act ivated comp le ment components to autologous RBCs. The de layed form of DHTR represents a typical e xa mple of th e bystander hemolytic mechanism [24] . The suppression of erythropoeisis that accompanies transfusion may also contribute to the increased anemia observed follo wing a DHTR. Marked ret iculocytopenia is not always a feature of DHTR. As patients with SCD have a shortened RBC survival, suppression of erythropoiesis has a profound effect on hemoglobin concentration compared to patients with norma l red cell lifespan.
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Controller Placement in Wireless Networks With Delayed CSI

Controller Placement in Wireless Networks With Delayed CSI

Theorem 5. For any arrival rate λ, and  > 0 satisfying λ + 1 ∈ Λ, the DCPS-N policy stabilizes the system if τ Q ≥ d max + T SS () for T SS () defined in (12). The DPCS-N policy differs from the DCPS policy in that controller placement decisions are only made in time slots which are multiples of N , but the controller placement cal- culation is the same as in DCPS. The scheduling portion of DCPS-N uses the delayed QLI with respect to the time at which the controller was placed, rather than the current time slot. This additional delay in QLI does not affect the throughput optimality of the policy. The proof of Theorem 5 follows similarly to the proof of Theorem 2, except using a T -slot drift argument at every time slot t = kN rather than every time slot.
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Controller placement for maximum throughput under delayed CSI

Controller placement for maximum throughput under delayed CSI

T SS () is the time required for the channel state process to approach its steady state distribution (i.e. the mixing time of the Markov process). Even though QLI is available at much less delay, the controller must use an older version of the QLI for throughput optimality. The reasoning behind this is related to the fact that long queues are typically located at nodes with OFF channels, and relocating the controller to those channels will not increase throughput; however, if the QLI is sufficiently delayed, the dependency between backlog and channel state is removed.

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Warm Nordic Seas delayed glacial inception in Scandinavia

Warm Nordic Seas delayed glacial inception in Scandinavia

A. Born et al.: Warm Nordic Seas delayed glacial inception in Scandinavia 823 ice accumulation was found sensitive to ocean heat transport into the Nordic Seas (Fig. 5). This implies a relation between sea surface temperature and Scandinavian mass balance that can be used to help constrain the timing of the last glacial inception with high-resolution marine proxy data. Avail- able terrestrial data for Scandinavia has much lower tempo- ral resolution. Sea surface temperatures of the Nordic Seas need to cool by at least 3 ◦ C from the 115 ka average for in- ception over southern Scandinavia. A 4 ◦ C cooling induces ice growth over northern Scandinavia. Cooling also has a positive effect on other known nucleation sites like western Siberia, the Siberian islands and Beringia (Brigham-Grette, 2001; Brigham-Grette et al., 2001; Svendsen et al., 2004).
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On the citation lifecycle of papers with delayed recognition

On the citation lifecycle of papers with delayed recognition

But what of the late bloomers that do not enjoy this – occasionally startling – success? Little seems to have been written specifically on the fate of the poorer cousins in the delayed recognition family. If the sleeping beauties and other Snow Whites are the princesses of this world, what of the shepherdesses, seamstresses and other common folk? In other words, how does late recognition affect the lifecycle of scientific papers? Is there a shift in time, a simple translation of the typical left-skewed distribution peaking 2, 3 years after publication followed by a slow decrease, or do papers with late recognition exhibit a different citation curve once they become cited? To what degree does the ultimate success of an article – in terms of its lifetime citations – affect, if even it does, the accumulation of citations? Does the behavior of sleeping beauties and “common” delayed-recognition papers mirror that of classics and “normal” papers? Finally, it is also known that the citation practices vary between disciplines (Finardi, 2013; Larivière et al., 2006), so what of this disciplinary effect? Do the sleepers behave the same in medicine, in physics or in the social sciences?
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Mitotic block and delayed lethality in HeLa epithelial cells exposed to Escherichia coli BM2-1 producing cytotoxic necrotizing factor type 1

Mitotic block and delayed lethality in HeLa epithelial cells exposed to Escherichia coli BM2-1 producing cytotoxic necrotizing factor type 1

Contribution of type 1 and F1C fimbriae to the CPE. The lack of cytotoxicity in culture supernatants of interaction cultures strongly suggested that a close contact between bacteria and HeLa cells was required to transfer the cyto- toxic activity. As reported above, a massive but loose binding was observed during the interaction period, with both the wild- type strain and the CNF1-deficient mutant. We examined the contributions of established fimbriae present on strain BM2-1, namely type 1 and F1C, to the induction of CPE and the loose-adhesion phenotype. For this purpose, we checked whether specific inhibitors of type 1 and F1C fimbriae were able to significantly decrease cytotoxic activity when added to the medium during the test of interaction. These inhibitors were mannose, for type 1 fimbriae (concentration, 1%), and F1C antiserum (concentration, 1/50). Tests were performed according to a dose-response protocol, by using 24 well- culture plates and four wells per experimental point. On day 7, total protein content of cell monolayers was quantified by methylene blue incorporation, as described in Materials and Methods. Whatever the bacterial inoculum used, no significant inhibition of CPE could be observed with either mannose or F1C antiserum (t test, P ⬎ 0.05). Concomitantly, we performed similar inhibition tests with Lab-Tek chamber slides, in order
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Electromagnetic hypersensitivity and occupational exposure to electromagnetic fields (EMF)

Electromagnetic hypersensitivity and occupational exposure to electromagnetic fields (EMF)

• all in very good physical and mental health (better than general population) • health problems disappeared after examination by experienced physicians. Guidelines when overexposure[r]

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Separation of delayed parameterized sources

Separation of delayed parameterized sources

Since the delayed source separation problem is ill-posed, strong assumptions are made to discriminate the sources. Most of the methods rely on the assumption that the sources are independent, like in the shifted independent component analysis method [5]. The source independence can be promoted by different ways, for instance with second order statistic methods either in temporal [6], [7] or frequency domains [3], [8]. Another strategy is to analyze the data in a domain where the sources are disjoint or uncorrelated, usually the time- frequency domain [2], [9], [10]. However, the independent and uncorrelated source assumptions do not hold in many real- world problems [11], so classical approaches cannot be applied. An early attempt to separate correlated sources was proposed in [12] using sparsity constraints on the sources: each mixture is sparsified, then the sparse representations are matched together
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