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991.
Jan Petersen Anthony W. Purcell Jamie Rossjohn 《Journal of molecular medicine (Berlin, Germany)》2009,87(11):1045-1051
The functionality of proteins is greatly extended by a diverse array of post-translational modifications (PTMs), many of which are recognized by the immune system. Notably, a significant proportion of peptides presented to T cells by the major histocompatibility complex in vivo are post-translationally modified. Since the cellular mechanisms that introduce and control protein modifications can differ between health and disease, the associated changes in antigen presentation have the potential to alter immune responses. A number of such situations have been implicated with infection, inflammation, autoimmune disease, and cancer, and the investigation of PTMs that affect antigen recognition has provided insight in disease progression as well as raising prospects for novel approaches in immunotherapy. 相似文献
992.
993.
Hilde?RH?de GeusEmail author Gijs?Fortrie Michiel?GH?Betjes Ron?HN?van Schaik AB?Johan?Groeneveld 《BMC nephrology》2013,14(1):273
Background
The predictive value of acute kidney injury (AKI) urinary biomarkers may depend on the time interval following tubular injury, thereby explaining in part the heterogeneous performance of these markers that has been reported in the literature. We studied the influence of timing on the predictive values of tubular proteins, measured before the rise of serum creatinine (SCr) in critically ill, non-septic patients.Methods
Seven hundred adult critically ill patients were prospectively included for urine measurements at four time-points prior to the rise in serum creatinine (T?=?0, -16, -20 and -24 h). Patients with sepsis and or AKI at ICU entry were excluded. The urinary excretion of the proteins, neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1), which are up-regulated in the distal and proximal tubules, respectively, were measured as well as the constitutive cytoplasmatic enzymes, π- and α-glutathione-S-transferase (GST), which are released by the distal and proximal tubules, respectively.Results
Five hundred and forty-three subjects were eligible for further analyses; however, 49 developed AKI in the first 48 h. Both NGAL (P?=?0.001 at T?=?-24 vs. non-AKI patients) and KIM-1 (P?<?0.0001 at T?=?0 vs. non-AKI patients) concentrations gradually increased until AKI diagnosis, whereas π- and α-GST peaked at T?=?-24 before AKI (P?=?0.006 and P?=?0.002, respectively vs. non-AKI patients) and showed a rapid decline afterwards. The predictive values at T?=?-24 prior to AKI were modest for π- and α-GST, whereas NGAL sufficiently predicted AKI at T?=?-24 and its predictive power improved as the time interval to AKI presentation decreased (area under the receiver operating characteristic curve; AUC?=?0.79, P?<?0.0001). KIM-1 was a good discriminator at T?=?0 only (AUC?=?0.73, P?<?0.0001).Conclusions
NGAL, KIM-1, pi- and alpha-GST displayed unique and mutually incomparable time dependent characteristics during the development of non-sepsis related AKI. Therefore, the time-relationship between the biomarker measurements and the injurious event influences the individual test results.994.
995.
J Morgan J F Spengler L Kuznetsova W T Coakley J Xu W M Purcell 《Toxicology in vitro》2004,18(1):115-120
Multi-cellular spheroids are increasingly employed as in vitro sensors of toxicants and a single spheroid can be used as a test object. An ultrasonic standing wave trap (USWT) can hold small particles in a medium-flowing system. This study investigated the conditions for holding HepG2 spheroids in an USWT and its relevance to use in toxicity testing. It can take many hours to reach a detectable end point of cell damage in a standard cellular in vitro toxicant assay and the process might be accelerated through increased sample flow past the spheroid. A USWT was employed here to levitate and hold HepG2 spheroids stationary against a flow of 3 mm s(-1) when the acoustic pressure amplitude is 1.9 MPa. The ultrasonic drive frequency was 1.64 MHz. Acoustic microstreaming in the standing wave chamber generated 1 mm s(-1) flow past a levitated spheroid-scale (80 microm diameter) latex particle in the absence of sample through-flow. The conditions required to form aggregates of cells of a HepG2 cell line in a single half wavelength ultrasonic standing wave mini-chambers are also described here. It is argued that the manipulation capabilities demonstrated may have potential in increasing the efficiency of in vitro toxicant detection by spheroids. Preliminary, visual (unquantified) fluorescence microscopy observations of spheroids levitated in the standing wave in the presence of the toxicant DL-propranolol do suggest accelerated loss of viability compared with controls. 相似文献
996.
The matrix metalloproteinases represent an attractive target for cancer treatment, and a number of matrix metalloproteinase inhibitors are undergoing clinical trials. The results of these studies will establish whether any of these compounds are therapeutically useful. Independent of the conclusions from the first generation of studies, the field of matrix metalloproteinase inhibitors remains attractive for creative and innovative research. In the future, the development of novel, less toxic, and more effective matrix metalloproteinase inhibitors, and the combination of conventional agents with these novel anticancer agents will constitute the main focus of research efforts. 相似文献
997.
Mahnaz R. Charania Khiya J. Marshall Cynthia M. Lyles Nicole Crepaz Linda S. Kay Linda J. Koenig Paul J. Weidle David W. Purcell 《AIDS and behavior》2014,18(4):646-660
A systematic review was conducted to identify evidence-based interventions (EBIs) for increasing HIV medication adherence behavior or decreasing HIV viral load among persons living with HIV (PLWH). We conducted automated searches of electronic databases (i.e., MEDLINE, EMBASE, PsycINFO, CINAHL) and manual searches of journals, reference lists, and listservs. Interventions were eligible for the review if they were U.S.-based, published between 1996 and 2011, intended to improve HIV medication adherence behaviors of PLWH, evaluated the intervention using a comparison group, and reported outcome data on adherence behaviors or HIV viral load. Each intervention was evaluated on the quality of study design, implementation, analysis, and strength of findings. Of the 65 eligible interventions, 10 are EBIs. The remaining 55 interventions failed to meet the efficacy criteria primarily due to null findings, small sample sizes, or low retention rates. Research gaps and future directions for development of adherence EBIs are discussed. 相似文献
998.
Potassium tellurite (K2TeO3) was found to be a potent antisickling agent that inhibited red cell sickling at concentrations less than 10 mumol/L. The inhibitory effect depended on the incubation time, with the effect increasing with longer incubation periods. Because tellurite causes swelling of red cells, and because the antisickling effect of tellurite correlated with the degree of red cell swelling, the antisickling effect of tellurite is assumed to be due to the decreased mean cell hemoglobin concentration. Swelling of red cells by tellurite was accelerated by the addition of reduced glutathione. Tellurite appears to be a new type of antisickling agent that interacts with the red cell membrane. 相似文献
999.
1000.