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921.
Antonio Lacquaniti Valentina Donato Basilio Pintaudi Giacoma Di Vieste Valeria Chirico Antoine Buemi Antonino Di Benedetto Adriana Arena Michele Buemi 《Acta diabetologica》2013,50(6):935-942
The aim of this study was to demonstrate that neutrophil gelatinase-associated lipocalin (NGAL) increased before the onset of microalbuminuria in patients with type 1 diabetes mellitus (T1DM), representing an important biochemical parameter with high sensitivity and specificity to make a precocious diagnosis of “normoalbuminuric” diabetic nephropathy (DN). Serum NGAL (sNGAL) and urinary NGAL (uNGAL) levels were evaluated in a cohort of fifty patients affected by T1DM. They had no signs of clinical nephropathy. Thirty-five healthy subjects (HS) were recruited. sNGAL levels were significantly higher compared with those measured in HS [193.7 (103.2–405.4) vs. 46.4 (39.8–56.2) ng/ml; p < 0.0001], as were uNGAL levels [25.5 (14.2–40.2) vs. 6.5 (2.9–8.5) ng/ml; p < 0.0001]. sNGAL was found to be directly correlated with glycated hemoglobin. uNGAL also positively correlated with albuminuria, whereas an inverse correlation was found with uric acid. After multivariate analysis, significance was maintained for the correlation between uNGAL and microalbuminuria. In ROC analysis, sNGAL showed a good diagnostic profile such as uNGAL. NGAL increases in patients with T1DM, even before diagnosis of microalbuminuria representing an early biomarker of “normoalbuminuric” DN with a good sensitivity and specificity. NGAL measurement could be useful for the evaluation of early renal involvement in the course of diabetes. 相似文献
922.
Heat-shock proteins chaperone antigenic peptides that are generated within cells. Such chaperoning is a part of the endogenous pathway of antigen presentation by MHC class I molecules. In addition, peptides that are chaperoned by heat-shock proteins, or are released by cell stress or death, are taken up by antigen-presenting cells and re-presented by their MHC molecules. 相似文献
923.
D.J. Antoine A.E. Mercer D.P. Williams B.K. Park 《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(8):565-577
Adverse drug reactions, in particular drug-induced hepatotoxicity, represent a major challenge for clinicians and an impediment to safe drug development. Novel blood or urinary biomarkers of chemically-induced hepatic stress also hold great potential to provide information about pathways leading to cell death within tissues. The earlier pre-clinical identification of potential hepatotoxins and non-invasive diagnosis of susceptible patients, prior to overt liver disease is an important goal. Moreover, the identification, validation and qualification of biomarkers that have in vitro, in vivo and clinical transferability can assist bridging studies and accelerate the pace of drug development. Drug-induced chemical stress is a multi-factorial process, the kinetics of the interaction between the hepatotoxin and the cellular macromolecules are crucially important as different biomarkers will appear over time. The sensitivity of the bioanalytical techniques used to detect biological and chemical biomarkers underpins the usefulness of the marker in question. An integrated analysis of the biochemical, molecular and cellular events provides an understanding of biological (host) factors which ultimately determine the balance between xenobiotic detoxification, adaptation and liver injury. The aim of this review is to summarise the potential of novel mechanism-based biomarkers of hepatic stress which provide information to connect the intracellular events (drug metabolism, organelle, cell and whole organ) ultimately leading to tissue damage (apoptosis, necrosis and inflammation). These biomarkers can provide both the means to inform the pharmacologist and chemist with respect to safe drug design, and provide clinicians with valuable tools for patient monitoring. 相似文献
924.
The coating of materials with specific films is widely used to improve material properties and many technologies exist to perform it. In the last few years, the replacement of wet electrodeposition processes has been continuously encouraged in the EU due to the problematic waste management linked to those processes. In this paper, magnetron sputtering is studied as an alternative to conventional electrodeposition by comparing the technologies’ environmental impacts and costs. From the study, it appears that while magnetron sputtering greatly reduces hexavalent chromium emissions over the production, it has an increased electricity consumption mostly due to its lower production capacity, thus leading to more greenhouse gas emissions. Furthermore, a short discussion on the quantification of the impact of hexavalent chromium emissions is conducted. Regarding costs, the electrodeposition process has a lower cost of investment and of consumables, but requires more work time for the different steps of the process, making the total price per functional unit roughly equal. However, the cost per functional unit strongly depends on assumptions on the required work time, for which a sensitivity study is performed. Finally, the impacts of these two competing coating processes are discussed to complete the technological comparison for the case of hard chromium deposition. 相似文献
925.
926.
Emeline Tabouret Fran?oise Boudouresque Maryline Barrie Mona Matta Celine Boucard Anderson Loundou Antoine Carpentier Marc Sanson Philippe Metellus Dominique Figarella-Branger L'Houcine Ouafik Olivier Chinot 《Neuro-oncology》2014,16(3):392-399
Background
A predictive marker of bevacizumab activity is an unmet medical need. We evaluated the predictive value of selected circulating prebiomarkers involved in neoangiogenesis and invasion on patient outcome in recurrent high-grade glioma treated with bevacizumab.Methods
Analyzed in plasma were a set of 11 prebiomakers of interest (vascular endothelial growth factor receptor [VEGF]; VEGF receptor 2; basic fibroblast growth factor; stromal cell derived factor 1; placenta growth factor; urokinase-type plasminogen activator; plasminogen activator inhibitor 1; matrix metalloproteinases 2, 7, and 9; and adrenomedulline), using ELISA, at baseline and 2 weeks after bevacizumab initiation in a prospective cohort of 26 patients (Cohort 1). Correlations were validated in a separate retrospective cohort (Cohort 2; n = 50) and tested in cohort patients treated with cytotoxic agents without bevacizumab (Cohort 3; n = 34). Dosages were correlated to objective response, progression-free survival (PFS), and overall survival (OS).Results
In Cohort 1, high MMP2 baseline level was associated with a probability of objective response of 83.3% versus 15.4% for low MMP2 level (P = .001). In multivariate analysis, baseline level of MMP2 correlated with PFS (hazard ratio, 3.92; 95% confidence interval [CI]:1.46–10.52; P = .007) and OS (hazard ratio, 4.62; 95% CI: 1.58–13.53; P = .005), as decrease of VEGF (P = .038 for PFS and P = .013 for OS) and MMP9 (P = .016 for PFS and P = .025 for OS). In Cohort 2, MMP2, but not MMP9, confirmed its predictive significance. In Cohort 3, no association was found between MMP2, MMP9, and outcome.Conclusion
In patients with recurrent high-grade glioma treated with bevacizumab, but not with cytotoxic agent, high MMP2 plasma levels are associated with prolonged tumor control and survival. MMP2 should be tested in randomized clinical trials that evaluate bevacizumab efficacy, and its biological role reassessed. 相似文献927.
Sarah Bailly Dominique Rousset Camille Fritzell Nathanaël Hoz Sarrah Ben Achour Lna Berthelot Antoine Enfissi Jessica Vanhomwegen Henrik Salje Sandrine Fernandes-Pellerin Mona Saout Anne Lavergne Jean-Claude Manuguerra Jean-Franois Carod Flix Djossou Simon Cauchemez Claude Flamand 《Viruses》2021,13(7)
Despite the health, social and economic impact of arboviruses in French Guiana, very little is known about the extent to which infection burden is shared between individuals. We conducted a large multiplexed serological survey among 2697 individuals from June to October 2017. All serum samples were tested for IgG antibodies against DENV, CHIKV, ZIKV and MAYV using a recombinant antigen-based microsphere immunoassay with a subset further evaluated through anti-ZIKV microneutralization tests. The overall DENV seroprevalence was estimated at 73.1% (70.6–75.4) in the whole territory with estimations by serotype at 68.9% for DENV-1, 38.8% for DENV-2, 42.3% for DENV-3, and 56.1% for DENV-4. The overall seroprevalence of CHIKV, ZIKV and MAYV antibodies was 20.3% (17.7–23.1), 23.3% (20.9–25.9) and 3.3% (2.7–4.1), respectively. We provide a consistent overview of the burden of emerging arboviruses in French Guiana, with useful findings for risk mapping, future prevention and control programs. The majority of the population remains susceptible to CHIKV and ZIKV, which could potentially facilitate the risk of further re-emergences. Our results underscore the need to strengthen MAYV surveillance in order to rapidly detect any substantial changes in MAYV circulation patterns. 相似文献
928.
Antoine G. Schneider Glenn M. Eastwood Rinaldo Bellomo Michael Bailey Miklos Lipcsey David Pilcher Paul Young Peter Stow John Santamaria Edward Stachowski Satoshi Suzuki Nicholas C. Woinarski Janine Pilcher 《Resuscitation》2013
Background
Arterial carbon dioxide tension (PaCO2) affects neuronal function and cerebral blood flow. However, its association with outcome in patients admitted to intensive care unit (ICU) after cardiac arrest (CA) has not been evaluated.Methods and results
Observational cohort study using data from the Australian New Zealand (ANZ) Intensive Care Society Adult-Patient-Database (ANZICS-APD). Outcomes analyses were adjusted for illness severity, co-morbidities, hypothermia, treatment limitations, age, year of admission, glucose, source of admission, PaO2 and propensity score.We studied 16,542 consecutive patients admitted to 125 ANZ ICUs after CA between 2000 and 2011. Using the APD-PaCO2 (obtained within 24 h of ICU admission), 3010 (18.2%) were classified into the hypo- (PaCO2 < 35 mmHg), 6705 (40.5%) into the normo- (35–45 mmHg) and 6827 (41.3%) into the hypercapnia (>45 mmHg) group. The hypocapnia group, compared with the normocapnia group, had a trend toward higher in-hospital mortality (OR 1.12 [95% CI 1.00–1.24, p = 0.04]), lower rate of discharge home (OR 0.81 [0.70–0.94, p < 0.01]) and higher likelihood of fulfilling composite adverse outcome of death and no discharge home (OR 1.23 [1.10–1.37, p < 0.001]). In contrast, the hypercapnia group had similar in-hospital mortality (OR 1.06 [0.97–1.15, p = 0.19]) but higher rate of discharge home among survivors (OR 1.16 [1.03–1.32, p = 0.01]) and similar likelihood of fulfilling the composite outcome (OR 0.97 [0.89–1.06, p = 0.52]). Cox-proportional hazards modelling supported these findings.Conclusions
Hypo- and hypercapnia are common after ICU admission post-CA. Compared with normocapnia, hypocapnia was independently associated with worse clinical outcomes and hypercapnia a greater likelihood of discharge home among survivors. 相似文献929.
Andrew V. Stachulski Thomas A. Baillie B. Kevin Park R. Scott Obach Deepak K. Dalvie Dominic P. Williams Abhishek Srivastava Sophie L. Regan Daniel J. Antoine Christopher E. P. Goldring Alvin J. L. Chia Neil R. Kitteringham Laura E. Randle Hayley Callan J. Luis Castrejon John Farrell Dean J. Naisbitt Martin S. Lennard 《Medicinal research reviews》2013,33(5):985-1080
The decline in approval of new drugs during the past decade has led to a close analysis of the drug discovery process. One of the main reasons for attrition is preclinical toxicity, frequently attributed to the generation of protein‐reactive drug metabolites. In this review, we present a critique of such reactive metabolites and evaluate the evidence linking them to observed toxic effects. Methodology for the characterization of reactive metabolites has advanced greatly in recent years, and is summarized first. Next, we consider the inhibition of key metabolic enzymes by electrophilic metabolites, as well as unfavorable drug–drug interactions that may ensue. One important class of protein‐reactive metabolites, not linked conclusively to a toxic event, is acyl glucuronides. Their properties are discussed in light of the safety characteristics of carboxylic acid containing drugs. Many adverse drug reactions (ADRs) are known collectively as idiosyncratic events, that is, not predictable from knowledge of the pharmacology and pharmacokinetics of the parent compound. Observed ADRs may take various forms. Specific organ injury, particularly of the liver, is the most direct: we examine this in some detail. Moving to the cellular level, we also consider the upregulation of induced cellular processes. The related, but distinct, issue of hypersensitivity or allergic reactions to drugs and their metabolites, possibly via the immune system, is considered next. Finally, we discuss the impact of such data on the drug discovery process, both through early detection of reactive metabolites and informed synthetic design, which eliminates unfavorable functionality from drug candidates. 相似文献
930.