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排序方式: 共有871条查询结果,搜索用时 31 毫秒
861.
Mortaz E Rad MV Johnson M Raats D Nijkamp FP Folkerts G 《Journal of molecular medicine (Berlin, Germany)》2008,86(9):1045-1056
The combination of inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists is increasingly used in chronic obstructive pulmonary disease (COPD). Recently, we have demonstrated that combination of salmeterol and fluticasone propionate (FP) additionally suppress the production of IL-8 by human monocyte. In this study, the molecular mechanism behind the effectiveness of this combination therapy is investigated in human neutrophils. Human neutrophils were preincubated with salmeterol or FP or the combination. The amount of interleukin-8 (IL-8), elastase and matrix metalloproteinases (MMP)-2 and -9 releases, and reactive oxygen species (ROS) generation and expression of MAP kinase phosphatase (MKP-1) and glucocorticoid receptor (GR) were determined. Cigarette smoke medium (CSM) induces an increased expression of CXC receptors and the production of ROS that may explain the strong production of IL-8 by neutrophils. The expression of CXC receptors, the production of ROS, and the release of elastase and MMP-2 and -9 were not influenced by salmeterol, FP, or the combination. Interestingly, the combination therapy had an additive suppressive effect on the CSM-induced production of IL-8. The latter could be explained by an increased mRNA expression of MKP-1, the GR and an increased translocation of the GR to the nucleus. This leads eventually to suppression of both the NF-kappaB and MAPK pathways and, hence, to less IL-8 production by the neutrophil. These data are in support for the use of a combination therapy in COPD patients. 相似文献
862.
Roodink I Kats G van Kempen L Grunberg M Maass C Verrijp K Raats J Leenders W 《The American journal of pathology》2008,173(6):1873-1881
Plexin D1 (PLXND1) is broadly expressed on tumor vessels and tumor cells in a number of different human tumor types. Little is known, however, about the potential functional contribution of PLXND1 expression to tumor development. Expression of semaphorin 3E (Sema3E), one of the ligands for PLXND1, has previously been correlated with invasive behavior and metastasis, suggesting that the PLXND1-Sema3E interaction may play a role in tumor progression. Here we investigated PLXND1 and Sema3E expression during tumor progression in cases of melanoma. PLXND1 was not expressed by melanocytic cells in either naevi or melanomas in situ, whereas expression increased with invasion level, according to Clark’s criteria. Furthermore, 89% of the metastatic melanomas examined showed membranous PLXND1-staining of tumor cells. Surprisingly, expression of Sema3E was inversely correlated with tumor progression, with no detectable staining in melanoma metastasis. To functionally assess the effects of Sema3E expression on tumor development, we overexpressed Sema3E in a xenograft model of metastatic melanoma. Sema3E expression dramatically decreased metastatic potential. These results show that PLXND1 expression during tumor development is strongly correlated with both invasive behavior and metastasis, but exclude Sema3E as an activating ligand. 相似文献
863.
Antibody phage display is a powerful tool for the generation of monoclonal antibodies against virtually any given antigen. Chickens are phylogenetically more distant from humans compared to other laboratory animals, such as mice and rats. Therefore, the use of chickens is especially beneficial when generating recombinant antibodies against human autoantigens, which are often highly conserved among mammals. Another advantage of using chickens in antibody phage display is that the preparation of single chain variable fragment (scFv) antibody libraries is faster and easier compared to preparing such libraries from other species, as only two primer sets are needed for amplification of the chicken variable heavy chain (V(H)) and variable light chain (V(L)) genes. In the present study we explored the possibility to immunize chickens with antigen cocktails for the generation of recombinant antibody fragments directed to a range of human autoantigens. Two pairs of chickens were immunized with two cocktails of seven recombinant autoantigenic proteins, libraries were prepared and panned on the individual proteins. The polyclonal chicken sera reacted strongly with most of the antigens used for immunization. By creating and screening single-chain variable fragment antibody phage display libraries, recombinant monoclonal antibody fragments were isolated successfully against the autoantigens annexin XI, centromere protein B, heat shock protein B3, DNA topoisomerase I, histidyl tRNA synthetase, Ro52, Ro60, Rpp30 and U1A. In conclusion, the immunization of only four chickens with two distinct pools of a total of 14 autoantigenic proteins allowed the isolation of scFvs against nine of these antigens. 相似文献
864.
Ella Koivuniemi Kathryn Hart Natalia Mazanowska Stefania Ruggeri Bernadette Egan Laura Censi Romana Roccaldo Lilja Mattila Pasquale Buonocore Eliisa Lyttyniemi Monique M. Raats Miroslaw Wielgos Kirsi Laitinen 《Nutrients》2022,14(14)
The aim was to investigate, among pregnant women, (1) the use of food supplements and (2) the awareness of food supplement recommendations and beliefs about food supplement use in four European countries: Finland, Italy, Poland, and the United Kingdom. The participants (n = 1804) completed an online questionnaire with predefined statements. Daily intakes of vitamins and minerals were calculated using uploaded pictures or weblinks of the supplement packages. Country differences were assessed. Most participants (91%) used at least one food supplement during pregnancy. A prenatal multivitamin was the most commonly used supplement type (84% of the users), and 75% of the participants thought consumption of multivitamin is recommended. Of the participants, 81% knew that folic acid is recommended during pregnancy while 58% knew the recommendation for vitamin D. In 19% of the supplement users, the daily safe upper intake limit of at least one nutrient was exceeded. Nevertheless, most participants agreed that they knew which supplements (91%) and doses of supplements (87%) needed to be used during pregnancy. To conclude, the majority of the participants used food supplements, but lower proportions knew and adhered to the recommended intakes. Between-country differences were observed in the use and knowledge of and beliefs regarding supplements. The results suggest a need for assessment and monitoring of supplement use in antenatal care to ensure appropriate use. 相似文献
865.
Laia Alemany Maëlle Saunier Isabel Alvarado‐Cabrero Beatriz Quirs Jorge Salmeron Hai‐Rim Shin Edyta C. Pirog Núria Guimer Gustavo Hernandez‐Suarez Ana Felix Omar Clavero Belen Lloveras Elena Kasamatsu Marc T. Goodman Brenda Y. Hernandez Jan Laco Leopoldo Tinoco Daan T. Geraets Charles F. Lynch Vaclav Mandys Mario Poljak Robert Jach Josep Verge Christine Clavel Cathy Ndiaye JoEllen Klaustermeier Antonio Cubilla Xavier Castellsagu Ignacio G. Bravo Michael Pawlita William G. Quint Nubia Muoz Francesc X. Bosch Silvia de Sanjos 《International journal of cancer. Journal international du cancer》2015,136(1):98-107
Knowledge about human papillomaviruses (HPV) types involved in anal cancers in some world regions is scanty. Here, we describe the HPV DNA prevalence and type distribution in a series of invasive anal cancers and anal intraepithelial neoplasias (AIN) grades 2/3 from 24 countries. We analyzed 43 AIN 2/3 cases and 496 anal cancers diagnosed from 1986 to 2011. After histopathological evaluation of formalin‐fixed paraffin‐embedded samples, HPV DNA detection and genotyping was performed using SPF‐10/DEIA/LiPA25 system (version 1) . A subset of 116 cancers was further tested for p16INK4a expression, a cellular surrogate marker for HPV‐associated transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance in the anal cancer data set. HPV DNA was detected in 88.3% of anal cancers (95% confidence interval [CI]: 85.1–91.0%) and in 95.3% of AIN 2/3 (95% CI: 84.2–99.4%). Among cancers, the highest prevalence was observed in warty–basaloid subtype of squamous cell carcinomas, in younger patients and in North American geographical region. There were no statistically significant differences in prevalence by gender. HPV16 was the most frequent HPV type detected in both cancers (80.7%) and AIN 2/3 lesions (75.4%). HPV18 was the second most common type in invasive cancers (3.6%). p16INK4a overexpression was found in 95% of HPV DNA‐positive anal cancers. In view of the results of HPV DNA and high proportion of p16INK4a overexpression, infection by HPV is most likely to be a necessary cause for anal cancers in both men and women. The large contribution of HPV16 reinforces the potential impact of HPV vaccines in the prevention of these lesions. 相似文献
866.
目的 观察大分割放疗联合唑来膦酸治疗肺癌骨转移的临床疗效及不良反应。方法 90例肺癌骨转移患者随机分成观察组(45例)和对照组(45例)。观察组静滴唑来膦酸4mg加局部大分割放疗30Gy/10f,之后再静滴唑来膦酸4mg×4~6次,1次/月;对照组则单纯放疗,方法剂量同上。结果 观察组止痛总有效率88.8%,显效率60%;对照组总有效率68.8%,显效率26.6%,两组比较P〈0.05。随访3个月后观察组与对照组止痛的总有效率分别为86.6%和57.5%(P〈0.05)。结论 大分割放疗联合唑来膦酸治疗肺癌骨转移,疗效确切,毒副反应轻,耐受性好。 相似文献
867.
Tobias Rautio Daan Vangerven Johan Dahlén Shimpei Watanabe Robert Kronstrand Svante Vikingsson Peter Konradsson Xiongyu Wu Henrik Gréen 《Drug testing and analysis》2023,15(7):711-729
Acetylbenzylfentanyl, benzoylbenzylfentanyl, 3-fluoro-methoxyacetylfentanyl, and 3-phenylpropanoylfentanyl are fentanyl analogs that have been reported to the European Monitoring Centre for Drugs and Drug Addiction in recent years. The aim of this study was to identify metabolic pathways and potential biomarker metabolites of these fentanyl analogs. The compounds were incubated (5 μM) with cryopreserved hepatocytes for up to 5 h in vitro. Metabolites were analyzed with liquid chromatography–quadrupole time of flight–high-resolution mass spectrometry (LC-QTOF-HRMS). The experiments showed that acetylbenzylfentanyl, benzoylbenzylfentanyl, and 3-phenylpropanoylfentanyl were mainly metabolized through N-dealkylation (forming nor-metabolites) and 3-fluoro-methoxyacetylfentanyl mainly through demethylation. Other observed metabolites were formed by mono-/dihydroxylation, dihydrodiol formation, demethylation, dehydrogenation, amide hydrolysis, and/or glucuronidation. The experiments showed that a large number of metabolites of 3-phenylpropanoylfentanyl were formed. The exact position of hydroxy groups in formed monohydroxy metabolites could not be established solely based upon recorded MSMS spectra of hepatocyte samples. Therefore, potential monohydroxy metabolites of 3-phenylpropanoylfentanyl, with the hydroxy group in different positions, were synthesized and analyzed together with the hepatocyte samples. This approach could reveal that the β position of the phenylpropanoyl moiety was highly favored; β-OH-phenylpropanoylfentanyl was the most abundant metabolite after the nor-metabolite. Both metabolites have the potential to serve as biomarkers for 3-phenylpropanoylfentanyl. The nor-metabolites of acetylbenzylfentanyl, benzoylbenzylfentanyl, and 3-fluoro-methoxyacetylfentanyl do also seem to be suitable biomarker metabolites, as do the demethylated metabolite of 3-fluoro-methoxyacetylfentanyl. Identified metabolic pathways and formed metabolites were in agreement with findings in previous studies of similar fentanyl analogs. 相似文献
868.
Judith Tommel Andrea W. M. Evers Henk W. van Hamersvelt Rien Jordens Sandra van Dijk Luuk B. Hilbrands Marc M. H. Hermans Daan A. M. J. Hollander Jos J. van de Kerkhof Marc A. G. J. ten Dam Henriët van Middendorp 《Seminars in dialysis》2023,36(2):131-141
Background
Dialysis patients are confronted with numerous, complex problems, which make it difficult to identify individual patient's most prominent problems. The objectives of this study were to (1) identify dialysis patients' most prominent problems from a patient perspective and (2) to calculate disease-specific norms for questionnaires measuring these problems.Methods
One hundred seventy-five patients treated with hemodialysis or peritoneal dialysis completed a priority list on several domains of functioning (e.g., physical health, mental health, social functioning, and daily activities) and a set of matching questionnaires assessing patient functioning on these domains. Patient priorities were assessed by calculating the importance ranking of each domain on the priority list. Subsequently, disease-specific norm scores were calculated for all questionnaires, both for the overall sample and stratified by patient characteristics.Results
Fatigue was listed as patients' most prominent problem. Priorities differed between male and female patients, younger and older patients, and home and center dialysis patients, which was also reflected in their scores on the corresponding domains of functioning. Therefore, next to general norm scores, we calculated corrections to the general norms to take account of patient characteristics (i.e., sex, age, and dialysis type).Conclusions
Results highlight the importance of having attention for the specific priorities and needs of each individual patient. Adequate disease-specific, norm-based assessment is not only necessary for diagnostic procedures but is an essential element of patient-centered care: It will help to better understand and respect individual patient needs and tailor treatment accordingly. 相似文献869.
Daan Zillen Kris L. L. Movig Gert Kant Joost B. Masselink Paola Mian 《Clinical Case Reports》2021,9(11)
BackgroundAcetaminophen hepatotoxicity is thought to be primarily caused by formation of the specific reactive metabolite N‐acetyl‐para‐benzo‐quinone imine (NAPQI). Malnourished individuals are at increased risk of acetaminophen‐related hepatotoxicity. We report a case of low acetaminophen clearance in a severely underweight young woman, and elaborate on the possible effects of malnutrition on the total clearance of acetaminophen as well as on the separate contributions of the different metabolic pathways.Case reportAn 18‐year‐old Caucasian woman weighing 43 kg with a history of eating disorder‐related hospital admissions presented at the emergency department after having ingested 33 tablets of acetaminophen 500 mg two hours earlier. She then received intravenous N‐acetylcysteine for 33 h. Nine hours after ingestion, the acetaminophen elimination half‐life (t½) was estimated to be >100 h.DiscussionWhile decreased total acetaminophen clearance (twofold) due to malnutrition has been reported in literature, the extremely low clearance in this specific patient cannot be explained. Malnourished individuals generally have reduced antioxidant reserves, coinciding with a shift in metabolic routes toward oxidative metabolism. This may result in increased formation of NAPQI and reduced neutralizing capacity, thereby increasing the risk of acetaminophen‐induced hepatotoxicity. Evidence for this observation can be found in animal and to a lesser extent in human studies. 相似文献
870.
Daan H. G. Hulsmans Evelien A. P. Poelen Anna Lichtwarck-Aschoff Roy Otten 《Journal of Applied Research in Intellectual Disabilities》2023,36(4):847-858