Effect of elevated serum prolactin concentrations on the immunophenotype of human lymphocytes, mitogen-induced proliferation and phagocytic activity of polymorphonuclear cells

It has been suggested that the immune system is an important target tissue of prolactin (PRL). We therefore investigated several immune parameters in nine patients with chronically elevated serum prolactin concentrations. The immunophenotype of lymphocytes, mitogen-induced lymphocyte proliferation and phagocytic activity of polymorphonuclear cells were determined under high serum prolactin levels and 2 weeks after treatment with dopamine agonists. An increased CD4/CD8 ratio in the hyperprolactinaemic patients could be detected compared with healthy control subjects, which remained high after treatment and did not seem to correlate with serum prolactin concentrations. Peripheral blood B lymphocytes showed an increased expression of CD69 in the treated group but not in untreated patients compared with healthy control subjects. Interleukin 2 receptor, CD45RO, transferrin receptor or HLA-DR expression of CD4 or CD8 cells, as well as oxidative burst and phagocytic activity of granulocytes, were not affected in the patients with prolactinomas. Lymphocyte transformation response to phytohaemagglutinin in vitro was found not to be influenced by elevated prolactin levels except at the highest mitogen concentration tested. These data together with previous reports suggest that, although PRL is required for lymphocyte maturation to achieve normal immune function, elevated PRL levels do not lead to an 'overstimulation' of the immune system in men.     

Model Failure and Context Switching Using Logic-Based Stochastic Models

This paper addresses parameter drift in stochastic models. We define a notion of context that represents invariant, stable-over-time behavior and we then propose an algorithm for detecting context changes in processing a stream of data. A context change is seen as model failure, when a probabilistic model representing current behavior is no longer able to “fit” newly encountered data. We specify our stochastic models using a first-order logic-based probabilistic modeling language called Generalized Loopy Logic (GLL). An important component of GLL is its learning mechanism that can identify context drift. We demonstrate how our algorithm can be incorporated into a failure-driven context-switching probabilistic modeling framework and offer several examples of its application.     

Dissection of antigenic and irritative effects of epicutaneously applied haptens in mice. Evidence that not the antigenic component but nonspecific proinflammatory effects of haptens determine the concentration-dependent elicitation of allergic contact dermatitis

Allergic contact dermatitis differs from most other immune reactions by its strict dose dependence during the elicitation phase. Moreover, almost all known contact allergens can also induce dose-dependent irritative dermatitis and in general only elicit allergic contact dermatitis in sensitized individuals when applied within a narrow dose range. Therefore, we hypothesized that elicitation of contact hypersensitivity (CHS) may require two signals, antigen-specific effector cell activation and a non-antigen-specific proinflammatory signal, both of which are provided by application of a sufficient dose of hapten. To dissociate these putative two signals, oxazolone-sensitized mice were ear challenged with a dose of the specific hapten which was too low to elicit CHS. At the same time, an unrelated hapten was applied in a conventional concentration to the same skin site. Whereas neither treatment alone elicited a significant CHS response, application of both compounds together resulted in a strong CHS response that was indistinguishable from that elicited by the full dose of the specific hapten. Upon coadministration of the irrelevant hapten, allergic contact dermatitis could be elicited even when the dose of the specific hapten was further reduced by a factor of 10(3). In contrast, a dose reduction of the irrelevant hapten by a factor of two resulted in the loss of the CRS response. These data indicate that non-antigen-specific effects of epicutaneously applied haptens significantly contribute to the elicitation of CHS responses and that the capacity of the hapten to evoke this proinflammatory stimulus rather than its antigenicity is responsible for the strict concentration dependence.     

An 8-fold {beta}{alpha} barrel protein with redundant folding possibilities

Protein sequences containing redundant segments of secondarystructure at both termini have the choice a priori of foldinginto several possible circularly permuted variants of the wild-typetertiary structure. To test this hypothesis the gene of phosphoribosylanthranilate isomerase from yeast, which is a single-domain8-fold ß barrel protein, was modified to produce a10-fold ß homologue in Escherichia coli. It containeda duplicate of the two C-terminal ß units of supersecondarystructure fused to its N-terminus. Most of the protein was recoveredfrom the insoluble fraction of disrupted cells by dissolutionin guanidinium chloride solutions and refolding. Pristine proteinwas purified from the soluble fraction. The purified (ß)₁₀proteins were enzymically almost fully active. Absorbance, fluorescenceand circular dichroism spectra as well as the reversible unfoldingbehaviour of both proteins were also very similar to the propertiesof the original (ß)₈ protein. Digestion with endopeptidasesconverted both the pristine and the refolded (ß)₁₀variant to the same large fragment that had the N-terminal sequenceand mol. wt of the wild-type ß)₈ protein. The datasuggest that the folding of the (ß)₁₀ variant is controlledthermodynamically both in vivo and in vitro.     

使用VAI-Q Strip 系统首次实现热轧带钢力学性能的全面控制

VAI-Q Strip（热轧带钢综合质量系统）是一种独特的计算机辅助质量控制系统，已在奥钢联林茨钢厂7机架热带轧机上成功实施。在1997年中期以来的稳定面连续的运行中，系统的预测功能在卷取后立即对带钢力学性能进行准确的在线预测。目前，系统的功能已扩展到可对带钢质量参数进行全自动在线控制，并且自2000年1月以来已在林茨厂热带轧机上成功运行。     

Cotreatment with racemic fenfluramine inhibits the development of tolerance to morphine analgesia in rats

This paper has been described an automatised method for determination of central dynamic moments of inertia of body segments. The method has been established for measuring female subjects. The body is sectioned into 16 segments, which are modelled using geometric solids. Measuring has been performed on 120 female subjects. Dynamic moments of inertia have been determined for all three axes of local co-ordinate systems in segments' centres of mass. The results are statistically analysed and divided into five percentile groups. Method described in this work represents simple, quickly and reliable manner of dynamic anthropomeasures determination.     

Impaired cutaneous immune responses in Thy-1-deficient mice

Thy-1 is a cell surface glycoprotein expressed mainly on brain and lymphoid tissue. Although the functions of Thy-1 are incompletely understood, evidence exists that Thy-1 participates in T cell activation. To examine the functional role of Thy-1 in cutaneous immune responses in vivo, Thy-1 gene-targeted mice (Thy-1-/-) and wild-type mice (Thy-1+/+) were immunized with the hapten oxazolone. After challenge with oxazolone, contact hypersensitivity responses in Thy-1-/- mice were reduced by 25% compared with Thy-1+/+ mice. Likewise, irritant dermatitis induced by croton oil was also decreased. In addition, Thy-1-/- mice showed a significantly reduced delayed-type hypersensitivity response after injection of allogeneic spleen cells into the hind footpads of allosensitized animals when compared with Thy-1+/+ mice. Moreover, proliferative responses to immobilized anti-CD3 were decreased in peripheral Thy-1-/- lymphocytes; this decrease was associated with a significantly reduced intracellular Ca2+ influx and protein tyrosine phosphorylation, indicating impairment of early lymphocyte activation. In contrast, the T cell proliferation induced by mitogens was normal, suggesting that Thy-1 expression weakly contributes to TCR-mediated T cell activation. Epidermal Langerhans cells and bone marrow-derived dendritic cells from Thy-1-/- mice exhibited a normal expression of costimulatory surface molecules as well as an unaltered ability to stimulate allogeneic T cells. Taken together, these findings demonstrate that a lack of Thy-1 expression does not generally compromise the immune system; however, Thy-1 expression may be involved in the fine-tuning of T cell-mediated immune responses.