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61.
R. A. Bradbury D. Shirkhedkar A. R. Glanville L. V. Campbell 《Internal medicine journal》2009,39(6):384-388
Background: The aim of this study was to determine whether pre-existing diabetes mellitus increases the risk of rejection, infection and/or death in cystic fibrosis patients undergoing bilateral sequential single-lung transplantation.
Methods: A retrospective audit of 25 consecutive patients with cystic fibrosis who underwent bilateral sequential single-lung transplantation between 1 January 2003 and 31 December 2005 at a tertiary referral hospital was carried out.
Results: Although 32% patients had diabetes diagnosed before lung transplantation, 92% had random blood glucose levels ≥11.1 mmol/L requiring insulin during admission. Patients with pre-existing diabetes had increased infection-related (3.9 vs 1.2, P = 0.01) and putative rejection-related (1.4 vs 0.5, P = 0.04) hospital admissions post-transplantation compared with those without diabetes pre-transplant. During the period of observation, four of eight patients with a prior diagnosis of diabetes died compared with none of 17 patients without prior diabetes ( P = 0.0055).
Conclusion: Almost all cystic fibrosis patients develop hyperglycaemia after lung transplantation, but patients with prior diabetes have more complication-related admissions to hospital and a higher mortality rate. 相似文献
Methods: A retrospective audit of 25 consecutive patients with cystic fibrosis who underwent bilateral sequential single-lung transplantation between 1 January 2003 and 31 December 2005 at a tertiary referral hospital was carried out.
Results: Although 32% patients had diabetes diagnosed before lung transplantation, 92% had random blood glucose levels ≥11.1 mmol/L requiring insulin during admission. Patients with pre-existing diabetes had increased infection-related (3.9 vs 1.2, P = 0.01) and putative rejection-related (1.4 vs 0.5, P = 0.04) hospital admissions post-transplantation compared with those without diabetes pre-transplant. During the period of observation, four of eight patients with a prior diagnosis of diabetes died compared with none of 17 patients without prior diabetes ( P = 0.0055).
Conclusion: Almost all cystic fibrosis patients develop hyperglycaemia after lung transplantation, but patients with prior diabetes have more complication-related admissions to hospital and a higher mortality rate. 相似文献
62.
63.
To overcome specific absorption rate (SAR) limitations of spin-echo-based MR imaging techniques, especially at (ultra) high fields, rapid acquisition relaxation enhancement/TSE (turbo spin echo)/fast spin echo sequences in combination with constant or variable low flip angles such as hyperechoes and TRAPS (hyperTSE) have been introduced. Due to the multiple spin echo and stimulated echo pathways involved in the signal formation, the contrast behavior of such sequences depends on both T2 and T1 relaxation times. In this work, constant and various variable flip angle sequences were analyzed in a volunteer study. It is demonstrated that a single effective echo time parameter TE(eff) can be calculated that accurately describes the overall T2 weighted image contrast. TE(eff) can be determined by means of the extended phase graph concept and is practically independent of field strength. Using the described formalism, the contrast of any TSE sequence can be predicted. HyperTSE sequences are demonstrated to show a robust and well-defined T2 contrast allowing clinical routine MRI to be performed with SAR reductions of typically at least 70%. 相似文献
64.
T. Saarne L. Kaiser H. Grönlund O. Rasool G. Gafvelin M. van Hage-Hamsten 《Clinical and experimental allergy》2005,35(5):657-663
BACKGROUND: Allergen-specific immunotherapy is the only treatment for allergic disease providing long-lasting symptom relief. Currently, it is mainly based on the use of crude allergen extracts. The treatment may be improved by the use of genetically engineered allergens, hypoallergens, aiming at a more effective and safer therapy. OBJECTIVE: The aim of this study was to provide a rational design of hypoallergen candidates for immunotherapy by using structural information and knowledge of B and T cell epitopes of an allergen. METHODS: The three-dimensional structure of the major cat allergen Fel d 1 was systematically altered by duplication of selected T cell epitopes and disruption of disulphide bonds. Seven Fel d 1 derivatives were generated and screened for allergenic reactivity in comparison with recombinant Fel d 1 in competition-ELISA. The allergenicity was further evaluated in basophil activation experiments and T cell reactivity was assessed in a lymphoproliferation assay. RESULTS: Three out of seven Fel d 1 derivatives, with two duplicated T cell epitopes and one or two disulphide bonds disrupted, were carefully evaluated. The three derivatives displayed a strong reduction in allergenicity with 400-900 times lower IgE-binding capacity than recombinant Fel d 1. In addition, they induced a lower degree of basophil activation and similar or stronger T cell proliferation than recombinant Fel d 1. CONCLUSION: By a rational approach, we have constructed three Fel d 1 hypoallergens with reduced IgE-binding capacities and retained T cell reactivities. This strategy may be applied to any well-characterized allergen to improve immunotherapy for allergic patients. 相似文献
65.
A. Purohit S. Laffer† C. Metz-Favre A. Verot F. Kricek‡ R. Valenta† G. Pauli 《Clinical and experimental allergy》2005,35(2):186-192
BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity. 相似文献
66.
67.
L. van den Bemt M. P. de Vries L. van Knapen M. Jansen M. Goossens J. W. M. Muris C. P. van Schayck 《Clinical and experimental allergy》2006,36(2):233-237
BACKGROUND: Exposure to a high level of house dust mite allergens (HDMAs) is considered as a risk factor for HDM sensitization and development of asthma in genetically disposed people. Mattresses are one of the most important sources of HDMA in people's living environment. OBJECTIVE: The aim of this study was to evaluate the association between mattress characteristics and HDMA concentrations on mattresses. METHODS: Dust samples of mattress surfaces were taken to evaluate the level of Der p 1 allergen. All participants filled in a questionnaire about the type of mattress, the type of covering (upper layer) of the mattress, dwelling characteristics and cleaning habits. Humidity and temperature of the bedroom were measured at the time of dust sampling. RESULTS: One hundred and sixty-eight questionnaires were filled in. Synthetic upper layer of the mattress was associated with a higher level of Der p 1 compared with cotton upper layer (2.6 vs. 0.8 microg/g Der p 1). Moreover, higher relative humidity (RH) was associated with significant higher concentrations and density of Der p 1. CONCLUSIONS: Two factors were associated with lower levels of Der p 1 found on mattresses, namely: a cotton upper layer of the mattress compared with a layer of synthetic material and lower RH at the time of sampling. As far as we know, the association between type of upper layer and concentration of Der p 1 has not been described before and could lead to the formulation of practical advices in order to reduce HDMA concentrations on mattresses. 相似文献
68.
J. Jayabharathi V. Thanikachalam A. Thangamani M. Padmavathy 《Medicinal chemistry research》2007,16(6):266-279
Some novel N(1)-arylidene-N(2)-cis-2,6-diphenyltetrahydrothiopyran-4-one azine derivatives were synthesised and their antibacterial activity against Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and antifungal activity against Candida-6, Candida-51, Aspergillus niger, and Aspergillus flavus were evaluated. 相似文献
69.
J. LEAKE S. J. KELLIE† J. PRITCHARD† J. M. CHESSELLS† R. A. RISDON 《Histopathology》1989,14(3):255-268
A review of the pathological material from 42 children with non-Hodgkin's lymphoma seen over a 44 month period revealed 10 large cell tumours. Of these, six were classified as peripheral T-cell lymphoma, an entity rarely reported in childhood. Three patients were boys and three girls (median age 9.5 years), and extranodal presentation was a feature of two patients. Five had high-grade tumours; of these, three were classified as large cell anaplastic, Ki-1 positive and two as pleomorphic large cell. The remaining patient had a low-grade tumour of angioimmunoblastic type. T-cell subsets were examined in three cases and showed the following phenotypes: CD4-, CD8-; CD4+, CD8-; CD4-, CD8+. Three of the patients with high-grade tumours died, with a mean survival of 22 weeks. The remaining patients are alive and clinically disease-free for between 10 and 24 months after treatment. 相似文献
70.
肝癌多药耐药产生与低糖环境的关系 总被引:5,自引:1,他引:4
目的探讨局部微环境低糖与肝细胞癌多药耐药性(MDR)产生的关系及影响机制。方法低糖培养HepG2细胞,应用流式细胞术Annexin V/PI法检测低糖培养的细胞在化疗药物5-氟脲嘧啶(5-Fu)作用后的凋亡情况,分别应用荧光定量聚合酶链反应(PCR)技术和Western blot技术检测低糖培养后HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP的mRNA和蛋白水平的表达。结果在低糖环境下生长时间越长的HepG2细胞对5-Fu的抵抗越强,而且随着低糖培养时间的增加,5-Fu诱导的HepG2细胞的凋亡高峰延迟。低糖培养的HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP在mRNA和蛋白水平的表达随低糖培养时间的延长而升高,以LRP的改变最为显著。结论肝癌生长微环境葡萄糖耐量不足也是肝癌产生MDR的原因之一。低糖可通过上调一组多药耐药相关基因的表达而诱导肝癌的多药耐药性。 相似文献