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41.
It is clear that functional heterogeneity of T cells may be explained by differential cytokine production. The aim of this paper was to review evidence for regulatory cells, generated after HgCl(2)-exposure. They differ from classical Th1 and Th2 cells, produce transforming growth factor-beta and interleukin-10 and exert their regulatory functions in a Th1/Th2-unrestricted fashion.  相似文献   
42.
Gelatin having p-nitrocinnamate pendant groups (Gel-NC) was prepared via an efficient one-pot synthesis, yield >87%. (1)H NMR data indicated that 1 mol of gelatin was modified with 18 +/- 6 mol of the photosensitive group. Upon exposure to low-intensity 365 nm UV light and in the absence of photoinitiators or catalysts, Gel-NC cross-linked within minutes into a gelatin-based hydrogel as monitored by UV-vis spectroscopy. The degree of swelling of this biodegradable hydrogel in aqueous solutions responded to changes in Gel-NC concentration levels, the ionic strength of the aqueous solutions, and photo-cross-linking time. Topography changes associated with phase transition resulting from "photocleavage" of the hydrogel network with 254 nm UV light were studied with AFM. Both Gel-NC and its hydrogel expressed low toxicity to human neonatal fibroblast cells. In addition, gelatin-based microgels were prepared via the photo-cross-linking of Gel-NC within inverse micelles.  相似文献   
43.
Studies were conducted to evaluate the effect of type, location, and colour of traps baited with 1 mg of the sex pheromone (Z)‐13‐hexadecen‐11‐ynyl acetate in polyethylene vials on the capture of the pine processionary moth, Thaumetopoea pityocampa (Denis & Schiffermüller) (Lepidoptera: Thaumetopoeidae), males. The experiments were carried out during two flight seasons in 2002 and 2003 at a low elevation Mediterranean pine forest on the hill of Goritsa (Magnesia, Thessaly, Central Greece). The hill is covered by approximately 120 ha of pines, among which Pinus brutia Ten. (Pinaceae) is predominant with Pinus halepensis Mill. (Pinaceae) as second most common species. Among the commercially available trap types used, the Delta and Pherocon II captured significantly more males than the Funnel trap. Furthermore, pine density had a significant effect on trap type and trap colour catches. Delta traps caught significantly more adults than the other two trap types in the low density pine stand, while in the medium and high‐density pine stands no significant differences were noted between Delta and Pherocon II traps. In addition, trap colour performance varied according to pine density; white‐ and yellow‐coloured traps caught significantly more males than the other two trap colours in the high‐density stand. The first adults were captured in traps during May, and traps continued to capture adults in low numbers (< two individuals per trap) until mid‐June. A period of 3–4 weeks of no trap captures followed until mid‐July, when captures restarted, at low numbers. The peak of T. pityocampa flight was observed during late August–September.  相似文献   
44.
Differential cytokine production by T cells plays an important role in regulating the nature of an immune response. In the rat, Brown-Norway (BN) and Lewis (LEW) strains differ markedly in their susceptibility to develop either type 1 or type 2-mediated autoimmune manifestations. BN rats are susceptible to type 2-dependent systemic autoimmunity, while LEW rats are resistant. Conversely, type 1-mediated, organ-specific autoimmune disease can be easily induced in LEW, but not in BN, rats. The mechanisms involved in the differential development of type 1 and type 2 immune responses by these two strains are still unknown. In the present study we analyzed the contributions of APC, CD4 and CD8 T cells, and MHC molecules in the difference between LEW and BN rats to develop a type 1 immune response. First, we show that the defect of BN T cells to produce type 1 cytokines in vitro does not require the presence of APC and, by using an APC-independent stimulation assay, we have localized the defect within the T cell compartment. Both CD4 and CD8 T cells are involved in the defect of BN rats to develop a type 1 immune response with a major contribution of the CD8 T cell compartment. This defect is associated with an increase in the type 2 cytokine IL-4 in both BN T cell populations, but neutralization of this cytokine does not restore this defect. Finally, by using MHC congenic rats, we show that the MHC haplotype is not involved in the defect of BN T cells to mount a proper type 1 cytokine response.  相似文献   
45.
The spleen is an infrequent site for metastatic lesions, and solitary splenic metastases from squamous cell carcinoma of the esophagus are very rare: only 4 cases have been reported thus far. These lesions are whitish nodules that are macroscopically and radiologically similar to primary splenic lymphomas. We report a case of metachronous splenic metastases from esophageal cancer and multiple splenic abscesses, which developed nine months after apparently curative esophagectomy without adjuvant chemotherapy. The patient underwent splenectomy dissection followed by adjuvant chemotherapy, but liver and skin metastases developed, and the patient died 9 months later.  相似文献   
46.
47.
The trace element molybdenum (Mo) is an essential component of key physiological systems in animals, plants and microorganisms. The molybdate oxoanion MoO(4)(2-) has been demonstrated to cause diverse yet poorly understood biochemical and pharmacological effects, such as non-specific inhibition of phosphatases and stabilization of steroid receptors. This study aimed to investigate the effects of molybdate on the activation of human peripheral blood lymphocytes (hPBLs) ex vivo and its potential interaction with the widely used immunosuppressant drug cyclosporin A (CsA). Lymphocyte activation was evaluated by performing multiple experiments determining blastogenesis in cultured peripheral blood lymphocytes obtained from 5 healthy volunteers, following stimulation induced by phytohemagglutinin (PHA), in the absence or presence of 0.05-10 mM sodium molybdate or/and 2.5-30 μg/mL CsA. Blastogenesis was assessed by a morphometric assay based on the relative proportions of unactivated lymphocytes, activated lymphoblasts and cells with aberrant morphology after PHA-induced activation. Molybdate concentrations up to 1 mM showed no effect on lymphocyte blastogenesis, while higher concentrations exerted immunosuppressive actions on cultured hPBLs. Co-administration of 0.1 mM sodium molybdate with CsA, at doses up to 20 μg/mL, induced no alteration in the response of cultured hPBLs to CsA. However, molybdate potentiated the immunosuppressive action of higher CsA concentrations, implying a likely dose-related synergistic interaction of the two agents in PHA-stimulated blood lymphocytes. These observations are indicative of the possible biological importance of molybdate oxoanions in the modulation of hPBL activation that may have pharmacological consequences during the therapeutic application of immunomodulatory drugs.  相似文献   
48.
Molecular and Cellular Biochemistry - Diabetes mellitus with the subsequent generation of reactive oxygen species represents a major risk factor for testicular dysfunction (TD). We investigate...  相似文献   
49.

Background

Recent evidence has underscored the role of hypoxia and angiogenesis in the pathogenesis of idiopathic fibrotic lung disease. Inhibitor of growth family member 4 (ING4) has recently attracted much attention as a tumor suppressor gene, due to its ability to inhibit cancer cell proliferation, migration and angiogenesis. The aim of our study was to investigate the role of ING4 in the pathogenesis of pulmonary fibrosis both in the bleomycin (BLM)-model and in two different types of human pulmonary fibrosis, including idiopathic pulmonary fibrosis (IPF) and cryptogenic organizing pneumonia (COP).

Methods

Experimental model of pulmonary fibrosis was induced by a single tail vein injection of bleomycin in 6- to 8-wk-old C57BL/6mice. Tissue microarrays coupled with qRT-PCR and immunohistochemistry were applied in whole lung samples and paraffin-embedded tissue sections of 30 patients with IPF, 20 with COP and 20 control subjects.

Results

A gradual decline of ING4 expression in both mRNA and protein levels was reported in the BLM-model. ING4 was also found down-regulated in IPF patients compared to COP and control subjects. Immunolocalization analyses revealed increased expression in areas of normal epithelium and in alveolar epithelium surrounding Masson bodies, in COP lung, whereas showed no expression within areas of active fibrosis within IPF and COP lung. In addition, ING4 expression levels were negatively correlated with pulmonary function parameters in IPF patients.

Conclusion

Our data suggest a potential role for ING4 in lung fibrogenesis. ING4 down-regulation may facilitate aberrant vascular remodelling and fibroblast proliferation and migration leading to progressive disease.  相似文献   
50.
Siannis F 《Biometrics》2004,60(3):704-714
In this article, we explore the use of a parametric model (for analyzing survival data) which is defined to allow sensitivity analysis for the presence of informative censoring. The dependence between the failure and the censoring processes is expressed through a parameter delta and a general bias function B(t, theta). We calculate the expectation of the potential bias due to informative censoring, which is an overall measure of how misleading our results might be if censoring is actually nonignorable. Bounds are also calculated for quantities of interest, e.g., parameter of the distribution of the failure process, which do not depend on the choice of the bias function for fixed delta. An application that relates to systematic lupus erythematosus data illustrates how additional information can result in reducing the uncertainty on estimates of the location parameter. Sensitivity analysis on a relative risk parameter is also explored.  相似文献   
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