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51.
Dirschka T Radny P Dominicus R Mensing H Brüning H Jenne L Karl L Sebastian M Oster-Schmidt C Klövekorn W Reinhold U Tanner M Gröne D Deichmann M Simon M Hübinger F Hofbauer G Krähn-Senftleben G Borrosch F Reich K Berking C Wolf P Lehmann P Moers-Carpi M Hönigsmann H Wernicke-Panten K Helwig C Foguet M Schmitz B Lübbert H Szeimies RM;AK-CT Study Group 《The British journal of dermatology》2012,166(1):137-146
Background Photodynamic therapy (PDT) with 5‐aminolaevulinic acid (ALA) or its methylester [methyl‐5‐aminolaevulinate (MAL) or 5‐amino‐4‐oxopentanoate] was recently ranked as first‐line therapy for the treatment of actinic keratosis (AK) and is an accepted therapeutic option for the treatment of neoplastic skin diseases. BF‐200 ALA (Biofrontera Bioscience GmbH, Leverkusen, Germany) is a gel formulation of ALA with nanoemulsion for the treatment of AK which overcomes previous problems of ALA instability and improves skin penetration. Objectives To evaluate the efficacy and safety of PDT of AKs with BF‐200 ALA in comparison with a registered MAL cream and with placebo. Methods The study was performed as a randomized, multicentre, observer‐blind, placebo‐controlled, interindividual trial with BF‐200 ALA, a registered MAL cream and placebo in a ratio of 3 : 3 : 1. Six hundred patients, each with four to eight mild to moderate AK lesions on the face and/or the bald scalp, were enrolled in 26 study centres in Germany, Austria and Switzerland. Patients received one PDT. If residual lesions remained at 3 months after treatment, PDT was repeated. Results PDT with BF‐200 ALA was superior to placebo PDT with respect to patient complete clearance rate (78·2% vs. 17·1%; P < 0·0001) and lesion complete clearance rate (90·4% vs. 37·1%) at 3 months after the last PDT. Moreover, superiority was demonstrated over the MAL cream regarding the primary endpoint patient complete clearance (78·2% vs. 64·2%; P < 0·05). Significant differences in the patient and lesion complete clearance rates and severity of treatment‐related adverse events were observed for the narrow‐ and broad‐spectrum light sources. Conclusions BF‐200 ALA is a very effective, well‐tolerated new formulation for AK treatment with PDT and is superior to a registered MAL medication. Efficacies and adverse events vary greatly with the different light sources used. 相似文献
52.
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,… 相似文献
53.
Arrhythmogenic Evidence for Epicardial Adipose Tissue: Heart Rate Variability and Turbulence are Influenced by Epicardial Fat Thickness 下载免费PDF全文
54.
BACKGROUND: The resistance of thrombi to fibrinolysis induced by plasminogen activators remains a major impediment to the successful treatment of thrombotic diseases. This study examines the contribution of activated factor XIII (factor XIIIa) to fibrinolytic resistance in experimental pulmonary embolism. METHODS AND RESULTS: The fibrinolytic effects of specific inhibitors of factor XIIIa-mediated fibrin-fibrin cross-linking and alpha2-antiplasmin-fibrin cross-linking were measured in anesthetized ferrets with pulmonary emboli. Five experimental groups were treated with heparin (100 U/kg) and/or tissue plasminogen activator (TPA, 1 mg/kg) and the percent (mean+/-SD) lysis of emboli was determined: (1) control, normal factor XIIIa activity (14.1+/-4. 8% lysis); (2) inhibited factor XIIIa activity (42.7+/-7.4%); (3) normal factor XIIIa activity+TPA (32.3+/-7.7%); (4) inhibited factor XIIIa activity+TPA (76.0+/-11.9%); and (5) inhibited alpha2-antiplasmin-fibrin cross-linking+TPA (54.7+/-3.9%). Inhibition of factor XIIIa activity increased endogenous lysis markedly (group 1 versus 2; P<0.0001), to a level comparable to that achieved with TPA (group 2 versus 3; P<0.05). Among groups receiving TPA, selective inhibition of factor XIII-mediated alpha2-antiplasmin-fibrin cross-linking enhanced lysis (group 3 versus 5; P<0.0005). Complete inhibition of factor XIIIa also amplified lysis (group 3 versus 4; P<0.0001) and had greater effects than inhibition of alpha2-antiplasmin cross-linking alone (group 4 versus 5; P<0.0005). No significant fibrinogen degradation occurred in any group. CONCLUSIONS: Factor XIIIa-mediated fibrin-fibrin and alpha2-antiplasmin-fibrin cross-linking both caused experimental pulmonary emboli to resist endogenous and TPA-induced fibrinolysis. This suggests that factor XIIIa may play a critical role in regulating fibrinolysis in human thrombosis. 相似文献
55.
To explore the potential use of prothymosin alpha(ProT), a putative thymic hormone, in gene therapy for bladder cancer, we generated a replication-defective recombinant retroviral vector encoding ProT and tested its antitumor effect on the MBT-2 murine bladder cancer. C3H/HeN mice injected with MBT-2 cells in conjunction with retroviruses encoding ProT exhibited smaller tumor mass, lower tumor incidence and higher survival rate, as well as higher antitumor cytotoxic activities compared with those injected with control viruses. However, such effects were not observed in severe combined immunodeficiency mice, suggesting that ProT exerts antitumor effects through its immunomodulatory activities. Cell growth in monolayer culture and colony formation in soft agar were enhanced in ProT gene-modified MBT-2 clones, and such growth-promoting activities of ProT could be reversed if its nuclear localization signal (NLS) was deleted. To circumvent the proliferation-promoting effect of ProT on tumor cells, a retroviral vector encoding ProT lacking NLS was constructed. Our results showed that retroviruses encoding NLS-deleted ProT was more efficacious than those encoding wild-type ProT in prolonging survival of tumor-bearing mice. This is the first report indicating that ProT, in particular NLS-deleted ProT, delivered by retroviral vectors may be further explored for the treatment of bladder cancer. 相似文献
56.
57.
PURPOSE: We have shown tumor-targeting and antitumor activities of an attenuated Salmonella choleraesuis in various tumor models. Meanwhile, host factors, including innate and adaptive immune responses, play roles in Salmonella-induced antitumor activity. Toll-like receptor 4 (TLR4) is identified as a signaling receptor for lipopolysaccharide derived from Gram-negative bacteria. However, the detailed mechanism of the S. choleraesuis-induced antitumor immune response via TLR4 remained uncertain. EXPERIMENTAL DESIGN: Herein, we used wild-type C3H/HeN mice and TLR4-deficient C3H/HeJ mice to study the role of TLR4 in the antitumor immune responses induced by S. choleraesuis. RESULTS: The amounts of S. choleraesuis were cleared more rapidly from the normal organs in C3H/HeN mice than those in C3H/HeJ mice. Tumors in C3H/HeN mice treated with S. choleraesuis were significantly smaller than those treated with PBS. By contrast, in TLR4-deficient mice, there was a slight difference in inhibition of tumor growth. Meanwhile, we found that S. choleraesuis significantly up-regulated IFN-gamma, IFN-inducible chemokines CXCL9 (MIG), and CXCL10 (IP-10) productions in C3H/HeN mice, but not in C3H/HeJ mice. Furthermore, immunohistochemical staining of the tumors revealed less intratumoral microvessel density, more infiltration of macrophages, neutrophils, CD4(+) and CD8(+) T cells, and cell death in C3H/HeN mice after S. choleraesuis treatment compared with those in C3H/HeJ mice. The interaction between TLR4 and S. choleraesuis seemed to polarize the T-cell response to a T helper 1-dominant state. CONCLUSIONS: These results suggest TLR4 may play an important role in the molecular mechanism of S. choleraesuis-induced host antitumor responses. 相似文献
58.
Shiau MY Tsai ST Hwang J Wu CY Chang YH 《European journal of endocrinology / European Federation of Endocrine Societies》2000,142(6):577-585
OBJECTIVE: In a preliminary cross-sectional study, we discovered that DNA topoisomerase II autoantibodies (anti-TopII) were detected in 49.2% of 195 Chinese type 1 diabetes mellitus (type 1 DM) patients with a mean age of 14.5 years and a mean duration of disease of 4.6 years. In order to demonstrate the relationship between anti-TopII and other immunological characteristics in Chinese type 1 DM patients, and to evaluate its putative prediction efficacy in Chinese patients, we simultaneously examined the frequency of anti-glutamic acid decarboxylase autoantibodies (anti-GAD), anti-TopII, antithyroglobulin/antimicrosomal autoantibodies (ATA/AMiA) and C-peptide concentrations in our patients in the present study. DESIGN AND METHODS: The frequency of anti-GAD and C-peptide levels, anti-TopII, and ATA/AMiA were examined in our patients by radioimmunoassay, enzyme-linked immunosorbant assay and hemagglutination respectively. Univariate comparisons were performed using Student's t-test for normal distributed data and Chi-square test for diclomatous data. Multivariate analysis was used for interpreting the independent risk factors which increased the incidence of anti-TopII. RESULTS AND CONCLUSIONS: The positivities for anti-GAD, anti-TopII, ATA/AMiA and C-peptide were 45.8%, 50.2%, 13.4% and 11.4% respectively. Anti-GAD and anti-TopII frequencies in our patients were similar when we stratified the patients by age, age at onset and duration. These observations imply that anti-GAD and anti-TopII remain persistent in Chinese patients with long-term type 1 DM duration. The most interesting finding is that anti-TopII frequency is more persistent than anti-GAD in our patients, especially when the diabetic duration is longer than 11 years. This indicates that anti-TopII, rather than anti-GAD, might act as a better indicator for monitoring the pathogenesis of Chinese type 1 DM patients especially in patients with a long-standing duration of disease. The late age of onset (>18 years) is a risk factor which increased the incidence of anti-TopII according to multivariate analysis. We further analyzed different manifestations between the youth- and adult-onset type 1 DM and found that adult-onset type 1 DM is characterized by better preservation of residual beta-cell function and higher frequencies of autoantibodies. 相似文献
59.
A recombinant plasmid, which contains the Pseudomonas aeruginosa exotoxin A (PE) gene with a C-terminal deletion, was inserted into expression vector pSecTag Xpress. The expression of this bacterial exotoxin in an animal cell was first demonstrated in 3T3 cell by transient transfection and western blot assay. Recombinant plasmid DNA was then injected intramuscularly to BALB/c mice, anti-PE specific antibodies were found in all animals vaccinated with plasmid containing the PE gene and with 'detoxicated' recombinant PE protein. Mice vaccinated with DNA were protected from the intoxication of lethal dosage of P. aeruginosa exotoxin A. Our results indicated that mice vaccinated with DNA encoding the PE gene could express PE protein in vivo, induced specific immune response, and provided sufficient protective immunity that safeguarded mice from the injection of lethal dosage of PE toxin. 相似文献
60.
Boon L Laman JD Ortiz-Buijsse A den Hartog MT Hoffenberg S Liu P Shiau F de Boer M 《Toxicology》2002,174(1):53-65
Monoclonal antibody (Mab) 5D12 is a potent antagonist of the CD40-CD40L pathway. This cellular interaction has been validated in a large number of experimental animal models where dys-regulation of the immune system plays a role. Chimeric 5D12 (ch5D12) was constructed to reduce the potential immunogenicity and enhance the in vivo half-life when used in humans. ch5D12 is a molecularly engineered human IgG(4) antibody containing the variable domains of the heavy and light chains of the murine version of 5D12 (mu5D12). This new chimeric Mab was tested in a marmoset experimental autoimmune encephalomyelitis model and was shown to effectively prevent disease symptoms. The results of this in vivo evaluation supported clinical use of ch5D12 for immune targeted diseases. Therefore GMP material was prepared and a GLP-compliant tissue cross-reactivity study on human tissues (3 donors/37 tissues) and cynomolgus tissues (2 donors/37 tissues) was performed. ch5D12 stained on the surface of B cells and selected dendritic cells and no unexpected cross-reactivity was observed. The identical staining patterns in human and cynomolgus tissues justified the use of cynomolgus monkeys as a relevant model for humans. A GLP-compliant safety and tolerability evaluation for ch5D12 in cynomolgus monkeys was performed using the GMP produced material. Weekly administration of ch5D12 at two dose levels for 4 weeks was shown to be safe and without any side effects in all monkeys. 相似文献