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21.
Antonia Sophie Wenners Keyur Mehta Sibylle Loibl Hyerim Park Berit Mueller Norbert Arnold Sigrid Hamann Joerg Weimer Beyhan Ataseven Silvia Darb-Esfahani Christian Schem Christoph Mundhenke Fariba Khandan Christoph Thomssen Walter Jonat Hans-Juergen Holzhausen Gunther von Minckwitz Carsten Denkert Maret Bauer 《PloS one》2012,7(10)
In our previous work we showed that NGAL, a protein involved in the regulation of proliferation and differentiation, is overexpressed in human breast cancer (BC) and predicts poor prognosis. In neoadjuvant chemotherapy (NACT) pathological complete response (pCR) is a predictor for outcome. The aim of this study was to evaluate NGAL as a predictor of response to NACT and to validate NGAL as a prognostic factor for clinical outcome in patients with primary BC. Immunohistochemistry was performed on tissue microarrays from 652 core biopsies from BC patients, who underwent NACT in the GeparTrio trial. NGAL expression and intensity was evaluated separately. NGAL was detected in 42.2% of the breast carcinomas in the cytoplasm. NGAL expression correlated with negative hormone receptor (HR) status, but not with other baseline parameters. NGAL expression did not correlate with pCR in the full population, however, NGAL expression and staining intensity were significantly associated with higher pCR rates in patients with positive HR status. In addition, strong NGAL expression correlated with higher pCR rates in node negative patients, patients with histological grade 1 or 2 tumors and a tumor size <40 mm. In univariate survival analysis, positive NGAL expression and strong staining intensity correlated with decreased disease-free survival (DFS) in the entire cohort and different subgroups, including HR positive patients. Similar correlations were found for intense staining and decreased overall survival (OS). In multivariate analysis, NGAL expression remained an independent prognostic factor for DFS. The results show that in low-risk subgroups, NGAL was found to be a predictive marker for pCR after NACT. Furthermore, NGAL could be validated as an independent prognostic factor for decreased DFS in primary human BC. 相似文献
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Matias C. Vieira Sophie Relph Walter Muruet-Gutierrez Maria Elstad Bolaji Coker Natalie Moitt Louisa Delaney Chivon Winsloe Andrew Healey Kirstie Coxon Alessandro Alagna Annette Briley Mark Johnson Louise M. Page Donald Peebles Andrew Shennan Baskaran Thilaganathan Neil Marlow Lesley McCowan Christoph Lees Deborah A. Lawlor Asma Khalil Jane Sandall Andrew Copas Dharmintra Pasupathy 《PLoS medicine》2022,19(6)
BackgroundAntenatal detection and management of small for gestational age (SGA) is a strategy to reduce stillbirth. Large observational studies provide conflicting results on the effect of the Growth Assessment Protocol (GAP) in relation to detection of SGA and reduction of stillbirth; to the best of our knowledge, there are no reported randomised control trials. Our aim was to determine if GAP improves antenatal detection of SGA compared to standard care.Methods and findingsThis was a pragmatic, superiority, 2-arm, parallel group, open, cluster randomised control trial. Maternity units in England were eligible to participate in the study, except if they had already implemented GAP. All women who gave birth in participating clusters (maternity units) during the year prior to randomisation and during the trial (November 2016 to February 2019) were included. Multiple pregnancies, fetal abnormalities or births before 24+1 weeks were excluded. Clusters were randomised to immediate implementation of GAP, an antenatal care package aimed at improving detection of SGA as a means to reduce the rate of stillbirth, or to standard care. Randomisation by random permutation was stratified by time of study inclusion and cluster size. Data were obtained from hospital electronic records for 12 months prerandomisation, the washout period (interval between randomisation and data collection of outcomes), and the outcome period (last 6 months of the study). The primary outcome was ultrasound detection of SGA (estimated fetal weight <10th centile using customised centiles (intervention) or Hadlock centiles (standard care)) confirmed at birth (birthweight <10th centile by both customised and population centiles). Secondary outcomes were maternal and neonatal outcomes, including induction of labour, gestational age at delivery, mode of birth, neonatal morbidity, and stillbirth/perinatal mortality. A 2-stage cluster–summary statistical approach calculated the absolute difference (intervention minus standard care arm) adjusted using the prerandomisation estimate, maternal age, ethnicity, parity, and randomisation strata. Intervention arm clusters that made no attempt to implement GAP were excluded in modified intention to treat (mITT) analysis; full ITT was also reported. Process evaluation assessed implementation fidelity, reach, dose, acceptability, and feasibility. Seven clusters were randomised to GAP and 6 to standard care. Following exclusions, there were 11,096 births exposed to the intervention (5 clusters) and 13,810 exposed to standard care (6 clusters) during the outcome period (mITT analysis). Age, height, and weight were broadly similar between arms, but there were fewer women: of white ethnicity (56.2% versus 62.7%), and in the least deprived quintile of the Index of Multiple Deprivation (7.5% versus 16.5%) in the intervention arm during the outcome period. Antenatal detection of SGA was 25.9% in the intervention and 27.7% in the standard care arm (adjusted difference 2.2%, 95% confidence interval (CI) −6.4% to 10.7%; p = 0.62). Findings were consistent in full ITT analysis. Fidelity and dose of GAP implementation were variable, while a high proportion (88.7%) of women were reached. Use of routinely collected data is both a strength (cost-efficient) and a limitation (occurrence of missing data); the modest number of clusters limits our ability to study small effect sizes.ConclusionsIn this study, we observed no effect of GAP on antenatal detection of SGA compared to standard care. Given variable implementation observed, future studies should incorporate standardised implementation outcomes such as those reported here to determine generalisability of our findings.Trial registrationThis trial is registered with the ISRCTN registry, ISRCTN67698474.Matias C Vieira and colleagues evaluate the Growth Assessment Protocol (GAP) for antenatal detection of small for gestational age in the DESiGN cluster randomised trial. 相似文献
24.
In vivo measurement of cortical impedance spectrum in monkeys: implications for signal propagation 总被引:2,自引:0,他引:2
To combine insights obtained from electric field potentials (LFPs) and neuronal spiking activity (MUA) we need a better understanding of the relative spatial summation of these indices of neuronal activity. Compared to MUA, the LFP has greater spatial coherence, resulting in lower spatial specificity and lower stimulus selectivity. A differential propagation of low- and high-frequency electric signals supposedly underlies this phenomenon, which could result from cortical tissue specifically attenuating higher frequencies, i.e., from a frequency-dependent impedance spectrum. Here we directly measure the cortical impedance spectrum in vivo in monkey primary visual cortex. Our results show that impedance is independent of frequency, is homogeneous and tangentially isotropic within gray matter, and can be theoretically predicted assuming a pure-resistive conductor. We propose that the spatial summation of LFP and MUA is determined by the size of these signals' generators and the nature of neural events underlying them, rather than by biophysical properties of gray matter. 相似文献
25.
Functional integrity of intravenous immunoglobulin following irradiation with a virucidal dose of gamma radiation. 总被引:3,自引:0,他引:3
Huan Tran Kristina Marlowe Keith McKenney Galina Petrosian Yuri Griko Wilson H Burgess William N Drohan Martin A Imboden Christoph Kempf Nicola Boschetti David M Mann 《Biologicals》2004,32(2):94-104
Although intravenous immunoglobulins (IVIG) and other plasma therapeutics have had a relatively good safety record, improved methods for viral clearance are constantly being evaluated and incorporated into new manufacturing processes. Gamma irradiation has been used routinely to assure sterility of healthcare products and medical devices, but it has not been applied successfully as a viral inactivation method for biologics. We examine whether virucidal doses of gamma irradiation (50 kGy) can be delivered to a manufacturing intermediate form of IVIG, a fractionated plasma paste, with negligible effect on structural and functional integrity of purified IgG product. Immunoglobulins from paste were examined for radiation-induced damage by SDS-PAGE and ELISAs utilizing viral antigens specific for rubella, CMV and mumps. Fc domain integrity was assessed by immunoblotting, quantitatively comparing the binding of irradiated and non-irradiated materials to cell surface Fcgamma receptors, and by employing quantitative RT-PCR to study the kinetics of accumulation of mRNA for the immune modulatory cytokines IL-1alpha, IL-1beta, IL-4, IL-8, IFNgamma, and TNFalpha. The results demonstrate that Fab and Fc domains of IVIG remain essentially intact and functional after gamma irradiation to virucidal doses, suggesting that this method could be used to enhance the safety of IVIG products. 相似文献
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27.
Eric Allan Wolfgang W. Weisser Markus Fischer Ernst-Detlef Schulze Alexandra Weigelt Christiane Roscher Jussi Baade Romain L. Barnard Holger Beßler Nina Buchmann Anne Ebeling Nico Eisenhauer Christof Engels Alexander J. F. Fergus Gerd Gleixner Marlén Gubsch Stefan Halle Alexandra M. Klein Ilona Kertscher Annely Kuu Markus Lange Xavier Le Roux Sebastian T. Meyer Varvara D. Migunova Alexandru Milcu Pascal A. Niklaus Yvonne Oelmann Esther Pašalić Jana S. Petermann Franck Poly Tanja Rottstock Alexander C. W. Sabais Christoph Scherber Michael Scherer-Lorenzen Stefan Scheu Sibylle Steinbeiss Guido Schwichtenberg Vicky Temperton Teja Tscharntke Winfried Voigt Wolfgang Wilcke Christian Wirth Bernhard Schmid 《Oecologia》2013,173(1):223-237
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination. 相似文献
28.
Siva Wu Xiaojin Li Manjula Gunawardana Kathleen Maguire Debbie Guerrero-Given Christoph Schaudinn Charles Wang Marc M. Baum Paul Webster 《PloS one》2014,9(7)
Non-typeable Haemophilus influenzae (NTHi) is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth) stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL) of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended. 相似文献
29.
Ewa Stach-Chilf Jerzy B. Warchol Prof. Dr. Christoph Pilgrim 《Cell and tissue research》1981,219(2):417-423
Summary The neurohypophysis of donor mice was implanted under the renal capsule of the recipients. The pituicytes survived while the neurosecretory axons disappeared. The ultrastructure of the glial cells was observed seven and nine weeks after transplantation. There were no signs of phagocytotic activity although remnants of axons were still present at seven weeks. The numerous processes of the pituicytes form a network with intercellular spaces wide in younger and narrower in older implants. The cells are connected by desmosomes and gap junctions. Pituicytes as well as blood vessels preserve their organotypic appearance. The transplant thus represents an experimental model for investigations on pituicytes in vivo in the absence of neurosecretory axons.Fellow of the Alexander von Humboldt-Stiftung. On leave from Department of Histology and Embryology, Institute of Biostructure, Academy of Medicine, Pozna, Poland 相似文献
30.
Tardive dyskinesia risk with first‐ and second‐generation antipsychotics in comparative randomized controlled trials: a meta‐analysis 下载免费PDF全文
Tardive dyskinesia (TD) risk with D2/serotonin receptor antagonists or D2 receptor partial agonists (second‐generation antipsychotics, SGAs) is considered significantly lower than with D2 antagonists (first‐generation antipsychotics, FGAs). As some reports questioned this notion, we meta‐analyzed randomized controlled studies (RCTs) to estimate the risk ratio (RR) and annualized rate ratio (RaR) of TD comparing SGAs vs. FGAs and SGAs vs. SGAs. Additionally, we calculated raw and annualized pooled TD rates for each antipsychotic. Data from 57 head‐to‐head RCTs, including 32 FGA and 86 SGA arms, were meta‐analyzed, yielding 32 FGA‐SGA pairs and 35 SGA‐SGA pairs. The annualized TD incidence across FGA arms was 6.5% (95% CI: 5.3‐7.8%) vs. 2.6% (95% CI: 2.0‐3.1%) across SGA arms. TD risk and annualized rates were lower with SGAs vs. FGAs (RR=0.47, 95% CI: 0.39‐0.57, p<0.0001, k=28; RaR=0.35, 95% CI: 0.28‐0.45, p<0.0001, number‐needed‐to‐treat, NNT=20). Meta‐regression showed no FGA dose effect on FGA‐SGA comparisons (Z=?1.03, p=0.30). FGA‐SGA TD RaRs differed by SGA comparator (Q=21.8, df=7, p=0.003), with a significant advantage of olanzapine and aripiprazole over other non‐clozapine SGAs in exploratory pairwise comparisons. SGA‐SGA comparisons confirmed the olanzapine advantage vs. non‐clozapine SGAs (RaR=0.66, 95% CI: 0.49‐0.88, p=0.006, k=17, NNT=100). This meta‐analysis confirms a clinically meaningfully lower TD risk with SGAs vs. FGAs, which is not driven by high dose FGA comparators, and documents significant differences with respect to this risk between individual SGAs. 相似文献