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排序方式: 共有805条查询结果,搜索用时 15 毫秒
1.
Aboudola S Kotloff KL Kyne L Warny M Kelly EC Sougioultzis S Giannasca PJ Monath TP Kelly CP 《Infection and immunity》2003,71(3):1608-1610
There is a strong association between serum antibody responses to toxin A and protection against Clostridium difficile diarrhea. A parenteral C. difficile toxoid vaccine induced very-high-level responses to anti-toxin A immunoglobulin G (IgG) in the sera of healthy volunteers. After vaccination, the concentrations of anti-toxin A IgG in the sera of all 30 recipients exceeded the concentrations that were associated with protection in previous clinical studies. Furthermore, the median concentration of serum anti-toxin A IgG in the test group was 50-fold higher than the previous threshold. These findings support the feasibility of using a vaccine to protect high-risk individuals against C. difficile-associated diarrhea and colitis. 相似文献
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Overexpressed eIF4E is functionally active in surgical margins of head and neck cancer patients via activation of the Akt/mammalian target of rapamycin pathway. 总被引:10,自引:0,他引:10
Cherie-Ann O Nathan Nazanin Amirghahari Fleurette Abreo Xiaohua Rong Gloria Caldito M Lamar Jones Huijuan Zhou Melanie Smith Donnellan Kimberly Jonathan Glass 《Clinical cancer research》2004,10(17):5820-5827
PURPOSE: Overexpression of eIF4E in surgical margins of head and neck cancer patients is an independent risk factor for recurrence. We hypothesize that overexpressed eIF4E is functionally active in tumor margins through activation of the Akt/mammalian target of rapamycin (mTOR) pathway EXPERIMENTAL DESIGN: Western blots and/or immunohistochemistry were performed to determine whether phosphorylation of mTOR and activation of its downstream molecules eIF4E-binding protein-1 (4E-BP1) and p70 S6 kinase and the upstream modulator of mTOR, Akt, were expressed in margins overexpressing eIF4E. RESULTS: There was a significant association between phospho-4E-BP1 and eIF4E expression of a margin or a significant difference in phospho-4E-BP1 expression between the eIF4E-positive and -negative margins (P < 0.01). A significant association between eIF4E and phospho-p70 S6 kinase as well as eIF4E and phospho-mTOR was also noted (P < 0.05). Western blot analysis indicated a highly significant difference in the phosphorylation status of 4E-BP1 between tumors and resection margins. A total of 89% of the 4E-BP1-expressing margins expressed more of the phosphorylated (beta, gamma, and delta) isoforms, whereas 81% of the 4E-BP1-expressing tumors expressed more of the unphosphorylated alpha isoform. A similar difference in Akt activation was noted between eIF4E-positive margins and tumors (P < 0.05). CONCLUSIONS: Overexpression of eIF4E is functionally active in tumor margins through activation of the Akt/mTOR signaling pathway. The greater degree of expression of downstream targets and upstream regulators of mTOR in margins compared with the tumors indicates preferential activation of the Akt/mTOR signaling pathway in margins overexpressing eIF4E. Rapamycin analogs can potentially be used as adjuvant therapy for patients with eIF4E-positive margins. 相似文献
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Giuseppe Luigi Banna Ornella Cantale Maria Monica Haydock Nicol Matteo Luca Battisti Kevin Bambury Naja Musolino Eoin OCarroll Giuseppe Maltese Lucia Garetto Alfredo Addeo Fabio Gomes 《The oncologist》2022,27(10):e796
BackgroundFrailty negatively affects the outcomes of patients with cancer, and its assessment might vary widely in the real world. The objective of this study was to explore awareness and use of frailty screening tools among the ONCOassist healthcare professionals (HCPs) users.Materials and MethodsWe sent 2 emails with a cross-sectional 15-item survey in a 3-week interval between April and May 2021. Differences in the awareness and use of tools according to respondents’ continents, country income, and job types were investigated.ResultsSeven hundred thirty-seven HCPs from 91 countries (81% physicians, 13% nurses, and 5% other HCPs) completed the survey. Three hundred and eighty-five (52%) reported assessing all or the majority of their patients; 518 (70%) at baseline and before starting a new treatment. Three hundred and four (43%) HCPs were aware of performance status (PS) scores only, 309 (42%) age/frailty/comorbidity (AFC) screening, and 102 (14%) chemotoxicity predictive tools. Five hundred and thirty-seven (73%) reported using tools; 423 (57%) just PS, 237 (32%) AFC, and 60 (8%) chemotoxicity ones. Reasons for tools non-use (485 responders) were awareness (70%), time constraints (28%), and uselessness (2%). There were significant differences in awareness and use of screening tools among different continents, country income, job types, and medical specialties (P < .001 for all comparisons).ConclusionAmong selected oncology HCPs, there is still a worldwide lack of knowledge and usage of frailty screening tools, which may differ according to their geography, country income, and education. Targeted initiatives to raise awareness and education are needed to implement frailty assessment in managing patients with cancer. 相似文献
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Eoin Moynihan Katrina Mackey Mark A. T. Blaskovich F. Jerry Reen Gerard McGlacken 《ACS medicinal chemistry letters》2022,13(8):1358
Antibiotic resistance has grown significantly in the last three decades, while research and development of new antibiotic classes has languished. Therefore, new chemical frameworks for the control of microbial behavior are urgently required. This study presents a novel suite of compounds, based on a tricyclic 4-hydroxy-2H-pyrano[3,2-c]quinoline-2,5(6H)-dione core, with significant antibiotic activity against the ESKAPE pathogens Staphylococcus aureus and Enterococcus faecalis and the “accidental pathogen” Staphylococcus epidermidis. A potent analogue with an N-heptyl-9-t-Bu substitution pattern emerged as a hit with MIC levels ≤2 μg/mL across four strains of MRSA. In addition, the same compound proved highly potent against Enterococcus spp. (0.25 μg/mL). 相似文献
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Matthew L. DeBoo Terry Bertozzi Stephen Donnellan Michael J. Mahony 《Conservation Genetics Resources》2012,4(4):1003-1005
A next generation sequencing approach was used to develop eight new microsatellite loci for the endangered Green and Golden Bell Frog (GGBF) Litoria aurea. Microsatellite loci were developed from six individuals and tested on another 20. Genetic variation and heterozygosity was high in most loci (mean number of alleles per locus?=?7.785; mean heterozygosity?=?0.785375). Samples from six other closely related species L. cyclorhyncha, L. dahlii (Queensland), L. dahlii (Northern Territory), L. moorei, L. raniformis, Cyclorana australis and C. maini were also genotyped. While these markers will be useful for studies involving L. aurea their use in other closely related species will be limited. 相似文献
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Li Y Boggia J Thijs L Hansen TW Kikuya M Björklund-Bodegård K Richart T Ohkubo T Kuznetsova T Torp-Pedersen C Lind L Ibsen H Imai Y Wang J Sandoya E O'brien E Staessen JA;International Database on Ambulatory Blood Pressure Monitoring in relation to Cardiovascular Outcomes Investigators 《Blood pressure monitoring》2008,13(3):145-147
The objective of this study was to investigate the prognostic significance of the ambulatory blood pressure (BP) during night and day and of the night-to-day BP ratio (NDR). We studied 7458 participants (mean age 56.8 years; 45.8% women) enrolled in the International Database on Ambulatory BP in relation to Cardiovascular Outcome. Using Cox models, we calculated hazard ratios (HR) adjusted for cohort and cardiovascular risk factors. Over 9.6 years (median), 983 deaths and 943 cardiovascular events occurred. Nighttime BP predicted mortality outcomes (HR, 1.18-1.24; P<0.01) independent of daytime BP. Conversely, daytime systolic (HR, 0.84; P<0.01) and diastolic BP (HR, 0.88; P<0.05) predicted only noncardiovascular mortality after adjustment for nighttime BP. Both daytime BP and nighttime BP consistently predicted all cardiovascular events (HR, 1.11-1.33; P<0.05) and stroke (HR, 1.21-1.47; P<0.01). Daytime BP lost its prognostic significance for cardiovascular events in patients on antihypertensive treatment. Adjusted for the 24-h BP, NDR predicted mortality (P<0.05), but not fatal combined with nonfatal events. Participants with systolic NDR of at least 1 compared with participants with normal NDR (> or = 0.80 to <0.90) were older, at higher risk of death, but died at higher age. The predictive accuracy of the daytime and nighttime BP and the NDR depended on the disease outcome under study. The increased mortality in patients with higher NDR probably indicates reverse causality. Our findings support recording the ambulatory BP during the whole day. 相似文献