Search results for "Liver"
showing 10 items of 4961 documents
Absorption of Drugs after Oral Administration
2007
After oral administration, drugs must be absorbed through the gastrointestinal tract to achieve the systemic circulation and exert their pharmacological effects. The successful formulation of an optimized oral drug delivery system requires a detailed consideration and a good understanding of the intestinal absorption process, its possibilities and limitations. This article gives an overview and update on the concepts, possibilities, and limitations of drug absorption after oral administration. Keywords: oral administration; drug absorption; oral drug delivery system; gastrointestinal tract; intestinal absorption
Protonation of the Biliverdin IXα Chromophore in the Red and Far-Red Photoactive States of a Bacteriophytochrome
2019
The tetrapyrrole chromophore biliverdin IXα (BV) in the bacteriophytochrome from Deinococcus radiodurans (DrBphP) is usually assumed to be fully protonated, but this assumption has not been systematically validated by experiments or extensive computations. Here, we use force field molecular dynamics simulations and quantum mechanics/molecular mechanics calculations with density functional theory and XMCQDPT2 methods to investigate the effect of the five most probable protonation forms of BV on structural stability, binding pocket interactions, and absorption spectra in the two photochromic states of DrBphP. While agreement with X-ray structural data and measured UV/vis spectra suggest that …
Phone-Controlled Delivery of NGN Services into Residential Environments
2008
The horizontally layered architecture of the IMS/NGN standards family enables the delivery of services independent of access network and requesting device. In this article, the authors propose a further separation of service control and delivery, allowing the requesting device - in particular a user's mobile phone - to invite other devices (we will focus on DLNA appliances) into the service delivery, enhancing both user experience and service design flexibility. The proposed solution builds on exploiting proximity technologies (e.g. barcodes, NFC) for pairing the control device with a remote environment. Motivated by scenarios, the architecture concepts are explained and a prototype that wa…
Molecular basis of the effects of argan oil on mitochondrial and peroxisomal metabolism of the fatty acids and inflammation
2012
The objective of this thesis work was to explore the molecular basis of Argan Oil (AO) effects on the mitochondrial and peroxisomal lipid metabolism and to elucidate its anti-inflammatory potential. We thus showed, initially, that the artisanal method preparation preserved the antioxidant properties of AO preventing the oxidation of the ferulic acid, by contrast to AO of commercial origin. Then, the treatment by the AO or lipopolysaccharides (LPS) of human fibroblasts, the cellular model of pseudo-neonatal adrenoleukodystrophy (P-NALD), revealed for the AO that peroxisomes proliferation is independent from the activation of the nuclear receptor PPARα and the co-activator PGC-1α. On the othe…
SOLID LIPID NANOPARTICLES FOR APPLICATIONS IN GENE THERAPY: A REVIEW OF THE STATE OF THE ART
2010
Importance of the field. Gene therapy represents a new paradigm in the prevention and treatment of many inherited and acquired diseases, including genetic disorders, such as cystic fibrosis, haemophilia and many somatic diseases, such as tumours, neurodegenerative diseases and viral infections, such as AIDS. Areas covered in this review. Among a large array of non-viral transfection agents used for in-vitro applications, cationic SLNs are the topic of this review, being recently proposed as an alternative carrier for DNA delivery, due to many technological advantages such as large-scale production from substances generally recognized as safe, good storage stability and possibility of steam …
Trehalose-hydroxyethylcellulose microspheres containing vancomycin for topical drug delivery.
2001
Abstract A new formulation, in which vancomycin is entrapped into trehalose and hydroxyethylcellulose (Natrosol ® ) spherical matrices, is described. Microspheres were produced by the solvent evaporation method. The entrapped drug was fully recovered following microspheres dissolution. Differential scanning calorimetry analyses proved that Natrosol maintains trehalose in its amorphous form. The stabilizing effects of trehalose on vancomycin were evaluated even after long storage and heating of microspheres. Calorimetric data indicated no decomposition of the entrapped drug. In vitro drug release, already performed by using a general two-compartment linear time-invariant open model, suggests…
Targeted-lung delivery of dexamethasone using gated mesoporous silica nanoparticles. A new therapeutic approach for acute lung injury treatment
2021
Acute lung injury (ALI) is a critical inflammatory syndrome, characterized by increased diffuse inflammation and severe lung damage, which represents a clinical concern due to the high morbidity and mortality in critical patients. In last years, there has been a need to develop more effective treatments for ALI, and targeted drug delivery to inflamed lungs has become an attractive research field. Here, we present a nanodevice based on mesoporous silica nanoparticles loaded with dexamethasone (a glucocorticoid extensively used for ALI treatment) and capped with a peptide that targets the TNFR1 receptor expressed in pro-inflammatory macrophages (TNFR-Dex-MSNs) and avoids cargo leakage. TNFR-D…
CT and MR Imaging Evaluation of Hepatic Adenoma
2006
Hepatic adenoma is a rare benign epithelial tumor that is usually encountered in young women who use oral contraceptives. It is clinically significant because of the risk of hemorrhage and of its low-grade malignancy potential. Adenomas usually are mildly hypervascular at contrast-enhanced CT and MR imaging, and heterogeneous due to the presence of hemorrhage, necrosis, calcifications and fat. The objective of our study was to illustrate the CT and MR imaging findings of hepatic adenoma.
Mitochondrial D310 mutations in colorectal adenomas: an early but not causative genetic event during colorectal carcinogenesis.
2008
Somatic mutations of the D310 sequence of the mitochondrial DNA are reported in human cancers, including colorectal cancers (CRC). The presence of these mutations at early or late steps of colorectal carcinogenesis is unknown. Their prevalence increased significantly with the number of cytosines in the D310 sequence of the matched normal tissue (D310 polymorphism), suggesting that this polymorphism could be a risk factor for CRC. The aim of this study was (i) to investigate the prevalence of D310 mutations in 64 colorectal adenomas and 36 liver metastases from 15 CRC patients, (ii) to assess the relation between D310 polymorphism and the risk of colorectal adenoma in a case-control study in…
Coexpression of IL-6 and soluble IL-6R causes nodular regenerative hyperplasia and adenomas of the liver
1998
Studies with tumor necrosis factor p55 receptor- and interleukin-6 (IL-6)-deficient mice have shown that IL-6 is required for hepatocyte proliferation and reconstitution of the liver mass after partial hepatectomy. The biological activities of IL-6 are potentiated when this cytokine binds soluble forms of its specific receptor subunit (sIL-6R) and the resulting complex interacts with the transmembrane signaling chain gp130. We show here that double transgenic mice expressing high levels of both human IL-6 and sIL-6R under the control of liver-specific promoters spontaneously develop nodules of hepatocellular hyperplasia around periportal spaces and present signs of sustained hepatocyte prol…