One of the attractive properties of artemisinins is their extremely fast-killing capability, quickly relieving malaria symptoms. Nevertheless, the unique benefits of these medicines are now compromised by the prolonged parasite clearance times and the increasing frequency of treatment failures, attributed to the increased tolerance of to artemisinin. This emerging artemisinin resistance threatens to undermine the effectiveness of antimalarial combination therapies.
View Article and Find Full Text PDFWnt/β-catenin signaling plays a critical role during development of both normal and malignant colorectal cancer tissues. Phosphorylation of β-catenin protein alters its trafficking and function. Such conventional allosteric regulation usually involves a highly specialized set of molecular interactions, which may specifically turn on a particular cell phenotype.
View Article and Find Full Text PDFMalaria is still one of the most prevalent parasitic infections in the world, with half of the world's population at risk for malaria. The effectiveness of current antimalarial therapies, even that of the most recent class of antimalarial drugs (artemisinin-combination therapies, ACTs), is under continuous threat by the spread of resistant Plasmodium strains. As a consequence, there is still an urgent requirement for new antimalarial drugs.
View Article and Find Full Text PDFGenetically modified Lactococcus lactis, non-pathogenic bacteria expressing the FNIII(7-10) fibronectin fragment as a protein membrane have been used to create a living biointerface between synthetic materials and mammalian cells. This FNIII(7-10) fragment comprises the RGD and PHSRN sequences of fibronectin to bind α5β1 integrins and triggers signalling for cell adhesion, spreading and differentiation. We used L.
View Article and Find Full Text PDFSecond generation biofuel production depends on lignocellulosic (LC) biomass transformation into simple sugars and their subsequent fermentation into alcohols. However, the main obstacle in this process is the efficient breakdown of the recalcitrant cellulose to sugar monomers. Hence, efficient feedstock pretreatment and hydrolysis are necessary to produce a cost effective biofuel.
View Article and Find Full Text PDFThe process of bioethanol production from biomass comprises pretreatments and enzyme-mediated hydrolysis to convert lignocellulose into fermentable sugars. Because of the recalcitrant character of cellulose, the enzymatic hydrolysis is considered the major challenge in this process to be economically competitive. These technical difficulties highlight the need for the discovery of new enzymes to optimize and lower the cost of current technologies.
View Article and Find Full Text PDFLactococcus lactis is modified to express a fibronectin fragment (FNIII₇₋₁₀) as a membrane protein. This interphase, based on a living system, can be further exploited to provide spatio-temporal factors to direct cell function at the material interface. This approach establishes a new paradigm in biomaterial surface functionalization for biomedical applications.
View Article and Find Full Text PDFCrit Rev Biotechnol
June 2014
The main challenge in second generation bioethanol production is the efficient breakdown of cellulose to sugar monomers (hydrolysis). Due to the recalcitrant character of cellulose, feedstock pretreatment and adapted hydrolysis steps are needed to obtain fermentable sugar monomers. The conventional industrial production process of second-generation bioethanol from biomass comprises several steps: thermochemical pretreatment, enzymatic hydrolysis and sugar fermentation.
View Article and Find Full Text PDFEmbryonic NANOG (NANOG1) is considered as an important regulator of pluripotency while NANOGP8 (NANOG-pseudogene) plays a role in tumorigenesis. Herein, we show NANOG is expressed from both NANOG1 and NANOGP8 in human colorectal cancers (CRC). Enforced NANOG1-expression increases clonogenic potential and tumor formation in xenograft models, although it is expressed only in a small subpopulation of tumor cells and is colocalized with endogenous nuclear β-catenin(High) .
View Article and Find Full Text PDFGoodpasture antigen-binding protein-1 (GPBP-1) is an exportable non-conventional Ser/Thr kinase that regulates glomerular basement membrane collagen organization. Here we provide evidence that GPBP-1 accumulates in the cytoplasm of differentiating mouse myoblasts prior to myosin synthesis. Myoblasts deficient in GPBP-1 display defective myofibril formation, whereas myofibrils assemble with enhanced efficiency in those overexpressing GPBP-1.
View Article and Find Full Text PDFThe Fbxw7 (F-box/WD repeat-containing protein 7; also called CDC4, Sel10, Ago, and Fbw7) component of the SCF (Skp1/Cullin/F-box protein) E3 ubiquitin ligase complex acts as a tumor suppressor in several tissues and targets multiple transcriptional activators and protooncogenes for ubiquitin-mediated degradation. To understand Fbxw7 function in the murine intestine, in this study, we specifically deleted Fbxw7 in the murine gut using Villin-Cre (Fbxw7(ΔG)). In wild-type mice, loss of Fbxw7 in the gut altered homeostasis of the intestinal epithelium, resulted in elevated Notch and c-Jun expression, and induced development of adenomas at 9-10 mo of age.
View Article and Find Full Text PDFAim: To determine the population pharmacokinetic parameters of vancomycin in neonatal patients with a wide range of gestational age and birth weight, and subsequently to design an initial dosing schedule for vancomycin in neonates.
Methods: Using nonlinear mixed-effects modelling (NONMEM VI), the pharmacokinetics of vancomycin were investigated in 70 neonates with postmenstrual age and body weight ranging 25.1-48.
Interactions between transcription and signaling are fundamentally important for understanding both the structure and function of genetic pathways and their role in diseases such as cancer. The finding that beta-catenin/TCF4 and JNK/c-Jun cooperate has important implications in carcinogenesis. Previously, we found that binding of c-Jun and beta-catenin/TCF4 to the c-jun promoter is dependent upon JNK activity, thus one role for this complex is to contribute to the repression and/or activation of genes that may mediate cell maintenance, proliferation, differentiation, and death, whereas deregulation of these signals may contribute to carcinogenesis.
View Article and Find Full Text PDFAn in vivo preclinical study has been made of the oral absorption of morphine (CAS 57-27-2) from a new sustained release formulation (morphine-Eudragit L complex, MEC), which had shown good sustained release properties in in vitro dissolution studies. The absorption of morphine from capsules filled with morphine hydrochloride trihydrate (MHT) or MEC was compared in fasted and fed dogs. Mean plasma morphine concentrations obtained after administration of MHT and MEC to fasted dogs were similar, and no statistically significant differences were found in the pharmacokinetic parameters of morphine (Cmax, Tmax and area under the plasma morphine concentration versus time curve from time zero to the last time with a detectable concentration of morphine).
View Article and Find Full Text PDFDiethyl dithiocarbamate (DEDTC) has been reported to be a more powerful inhibitor of all-trans-retinoic acid (ATRA) in vitro metabolism than the well-established cytochrome P450 (CYP) inhibitor ketoconazole (KC). In recent years grapefruit juice (GJ) has been shown to be able to increase the oral bioavailability of several drugs by inhibiting intestinal CYP. This study investigated the in vivo effect of these CYP inhibitors on the pharmacokinetics of ATRA.
View Article and Find Full Text PDFThe time-dependent elimination kinetics of all-trans-retinoic acid (ATRA) has been associated with autoinduction of its metabolism and has led to the hypothesis that rapid development of acquired clinical resistance to ATRA may be prevented by coadministration of metabolic inhibitors. This study in rats was performed to investigate the pharmacokinetics and onset of time-dependent elimination of ATRA, with the purpose of establishing an animal model suitable for in vivo preclinical studies of compounds capable of inhibiting ATRA metabolism. After the intravenous (IV) bolus administration of single doses of ATRA (1.
View Article and Find Full Text PDFPurpose: Cyclosporine A (CyA) is able to inhibit P-glycoprotein (P-gp) and to increase cytotoxicity of some anticancer drugs, including etoposide. However, the effect of CyA on the distribution of etoposide in normal tissues, which could affect their toxicity, has not been studied extensively. The purpose of this study was to investigate the effect of CyA on the pharmacokinetics and tissue distribution of etoposide in rats.
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