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Background:CYP2D6is responsible for the metabolism of approximately 25% of all drugs. The expression of cytochrome P450 2D6 (CYP2D6) is influenced by a combination of factors including polymorphisms in theCYP2D6gene. Analysis of theCYP2D6genotype is used to personalize the medication to a patient’s metabolism. Although many genotypes can be determined using standard genotype analysis, in some cases, an incomplete analysis is performed. TheCYP2D6genotype *1/*4 often occurs in combination with a multiplication of theCYP2D6gene, and is reported as (*1/*4)xN. Accurate determination of the multiplied gene is essential to provide a phenotype prediction for these patients. Duplication of the *1 gene leads to an extensive metabolizer genotype whereas multiplication of the *4 gene would not lead to extra functional enzyme and therefore provides an intermediate metabolizer phenotype.Methods:Here, a technique is described in which the copy numbers of both the *4 and *1 genes are determined using quantitative PCR techniques.Results and conclusions:This technique provides a method to predict the patient’sCYP2D6phenotype, and is therefore an important step toward personalized medicine.

The therapeutic application of nanomaterials requires that they are biocompatible and can reach the desired target. The innate immune system is likely to be the first defence machinery that would recognise the nanomaterials as 'non-self'. A number of studies have addressed the issue of how carbon nanotubes (CNTs) interact with phagocytic cells and their surface receptors that can impact on their intracellular processing and subsequent immune response. In addition, soluble innate immune factors also get involved in the recognition and clearance of CNTs. The interaction of CNTs with the complement system, the most potent and versatile innate immune mechanism, has shed interesting light on how complement activation on the surface of CNTs can modulate their phagocytosis and effector cytokine response. The charge or altered molecular pattern on the surface of CNTs due to functionalization and derivatization can also dictate the level of complement activation and subsequent inflammatory response. It is becoming evident that complement deposition may facilitate phagocytic uptake of CNTs through receptor routes that leads to dampening of pro-inflammatory response by complement-receptor bearing macrophages and B cells. Thus, recombinant complement regulators decorated on the CNT surface can constructively influence the therapeutic strategies involving CNTs and other nanoparticles.

Carbon nanotubes (CNTs) have promised a range of applications in biomedicine. Although influenced by the dispersants used, CNTs are recognized by the innate immune system, predominantly by the classical pathway of the complement system. Here, we confirm that complement activation by the CNT used here continues up to C3 and C5, indicating that the entire complement system is activated including the formation of membrane-attack complexes. Using recombinant forms of the globular regions of human C1q (gC1q) as inhibitors of CNT-mediated classical pathway activation, we show that C1q, the first recognition subcomponent of the classical pathway, binds CNTs via the gC1q domain. Complement opsonisation of CNTs significantly enhances their uptake by U937 cells, with concomitant downregulation of pro-inflammatory cytokines and up-regulation of anti-inflammatory cytokines in both U937 cells and human monocytes. We propose that CNT-mediated complement activation may cause recruitment of cellular infiltration, followed by phagocytosis without inducing a pro-inflammatory immune response. Carbon nanotubes (CNTs) are recognized by the innate immune system, especially by the classical pathway of the complement system. Complement activation is usually associated with a pro-inflammatory response. Here, we show that complement deposition on CMC- and RNA-CNTs can enhance their uptake by phagocytes, which in turn, leads to dampening of pro-inflammatory cytokine production. It appears that CNT-mediated complement activation may cause recruitment of cellular infiltration, followed by enhanced phagocytosis and suppression of cytokine storm.

Carbon nanotubes (CNTs) are increasingly being developed for use in biomedical applications, including drug delivery. One of the most promising applications under evaluation is in treating pulmonary diseases such as tuberculosis. Once inhaled or administered, the nanoparticles are likely to be recognised by innate immune molecules in the lungs such as hydrophilic pulmonary surfactant proteins. Here, we set out to examine the interaction between surfactant protein D (SP-D), a key lung pattern recognition molecule and CNTs, and possible downstream effects on the immune response via macrophages. We show here that a recombinant form of human SP-D (rhSP-D) bound to oxidised and carboxymethyl cellulose (CMC) coated CNTs via its C-type lectin domain and enhanced phagocytosis by U937 and THP-1 macrophages/monocytic cell lines, together with an increased pro-inflammatory response, suggesting that sequestration of SP-D by CNTs in the lungs can trigger an unwanted and damaging immune response. We also observed that functionalised CNTs, opsonised with rhSP-D, continued to activate complement via the classical pathway, suggesting that C1q, which is the recognition sub-component of the classical pathway, and SP-D have distinct pattern recognition sites on the CNTs. Consistent with our earlier reports, complement deposition on the rhSP-D opsonised CNTs led to dampening of the pro-inflammatory immune response by THP-1 macrophages, as evident from qPCR, cytokine array and NF-κB nuclear translocation analyses. This study highlights the importance of understanding the interplay between innate immune humoral factors including complement in devising nanoparticle based drug delivery strategies.

Magnetic drug delivery is a promising method to target a drug to a diseased area while reducing negative side effects caused by systemic administration of drugs. In magnetic drug delivery a therapeutic agent is coupled to a magnetic nanoparticle. The particles are injected and at the target location withdrawn from blood flow by a magnetic field. In this study a FePd nanowire is developed with optimised properties for magnetic targeting. The nanowires have a high magnetic moment to reduce the field gradient needed to capture them with a magnet. The dimensions and the materials of the nanowire and coating are such that they are dispersable in aqueous media, non-cytotoxic, easily phagocytosed and not complement activating. This is established in several in-vitro tests with macrophage and endothelial cell lines.Along with the nanowires a magnet is designed, optimised for capture of the nanowires from the blood flow in the hind leg of a rat. The system is used in a pilot scale . in-vivo experiment. No negative side effects from injection of the nanowires were found within the limited time span of the experiment. In this first pilot experiment no nanowires were found to be targeted by the magnet, or in the liver, kidneys or spleen, most likely the particles were removed during the fixation procedure.

Prescription of clozapine is complicated by the occurrence of clozapine-induced reduction of neutrophils. The aim of this study was to identify genetic risk factors in a population of 310 Dutch patients treated with clozapine, including 38 patients developing neutropenia and 31 patients developing agranulocytosis. NQO2 1541AA (NRH quinone oxidoreductase 2; protects cells against oxidative metabolites) was present at a higher frequency in agranulocytosis patients compared with control (23% versus 7%, P=0.03), as was ABCB1 (ABC-transporter-B1; drug efflux transporter) 3435TT (32% versus 20%, P=0.05). In patients developing neutropenia, ABCB1 3435TT and homozygosity for GSTT1

Organizing magnetic nanoparticles into long-range and dynamic assemblies would not only provide new insights into physical phenomena but also open opportunities for a wide spectrum of applications. In particular, a major challenge consists of the development of nanoparticle-based materials for which the remnant magnetization and coercive field can be controlled at room temperature. Our approach consists of promoting the self-organization of magnetic nanoparticles in liquid crystals (LCs). Using liquid crystals as organizing templates allows us to envision the design of tunable self-assemblies of magnetic nanoparticles, because liquid crystals are known to reorganize under a variety of external stimuli. Herein, we show that twisted liquid crystals can be used as efficient anisotropic templates for superparamagnetic nanoparticles and demonstrate the formation of hybrid soft magnets at room temperature.

Magnetic nanoparticles (MNPs) reveal promising opportunities for biomedical applications, potentially allowing minimally invasive diagnosis and therapeutic usage at several levels of human body organization (cells, tissue and organs). An increasingly broad collection of MNPs has been recently developed not only at the research level but also in some specific cases for medical applications. Superparamagnetic iron oxide (SPIO) nanoparticles are commonly used in clinical practice as contrast agents for magnetic resonance imaging (MRI) of liver and angiography. Carbon nanotubes (CNTs) are another type of nanomaterials with great potential for biomedical applications. Filled with ferromagnetic materials, an ensemble of aligned CNTs displays a highly non-linear, anisotropic and hysteretic magnetization behaviour due to their extremely high aspect ratio (length/diameter >100). The intrinsic properties of such ferromagnetic nanoparticles can potentially improve diagnosis and therapy of numerous diseases. Combining tailored biocompatible ferromagnetic nanomaterials with dedicated detection technology can provide a new approach leading to the exciting perspective of accurate medical imaging and medical therapy (magnetic hyperthermia, targeted drug delivery, etc.) at the cellular level. Elongated Fe-filled CNTs (Fe-CNTs) are foreseen as potential nanotools leading to minimally invasive, highly sensitive, and cost effective novel investigation routes for complete human body systems.

A major function of the human innate immune system is to recognize non-self: i.e., invading microorganisms or altered, damaged self macromolecules and cells. Various components of the human immune system recognize foreign synthetic materials, including carbon nanotubes (CNTs). The complement system proteins in blood, and the collectins, SP-A and SP-D in the lungs bind to carbon nanotubes, in competition with other plasma proteins, and may influence their subsequent adhesion to and uptake by cells and their localization in the body. Modification of the surface chemistry of carbon nanotubes alters their binding to complement proteins and collectins, and provides information on the mechanism by which binding of these proteins occurs.

Contains fulltext : 69093.pdf (Publisher’s version ) (Closed access) CONTEXT: Systematic transrectal ultrasound-guided biopsy (TRUSBx) is the gold standard for detecting prostate cancer. This systematic approach is characterized by low sensitivity (39-52%) and high specificity (81-82%). Magnetic resonance (MR)-guided biopsy techniques are becoming more and more available, but there is no current consensus on the optimal technique. OBJECTIVE: This review presents an overview of MR-guided biopsy techniques for prostate cancer detection. EVIDENCE ACQUISITION: Current literature was reviewed regarding MR-guided biopsy for prostate cancer detection. A literature search was performed using the commercially available MedLine online search engine. Combinations of the following search and Medical Subject Headings terms were applied to retrieve relevant articles: "magnetic resonance," "prostatic neoplasms," and "biopsy." Review articles and studies describing techniques other than MR-guided biopsy were excluded. EVIDENCE SYNTHESIS: Biopsy of the prostate is an essential procedure for determining optimal treatment. Systematic TRUSBx is the gold standard, but it fails to detect numerous tumors. Diagnostic MR imaging provides more accurate selection of regions in which tumors are suspected. Using these diagnostic images during an MR-directed biopsy procedure improves quality of the biopsy. In open MR scanners, the prebiopsy images often must be registered to the real-time biopsy images because open MR scanners do not provide optimal tissue contrast; thus, the patient must first be examined in a closed MR scanner and then biopsied in an open scanner. The advantage of open MR over closed MR is that the physician has easy patient access. With special equipment, prostate MR-guided biopsy is also possible in a closed system. Closed MR scanners can be used for the prebiopsy scan as well as for the biopsy procedure. CONCLUSIONS: The combination of a diagnostic MR examination and MR-guided biopsy is a promising tool and may be used in patients with previous negative TRUSBx.