Peptide functionalized superparamagnetic iron oxide nanoparticles as MRI contrast agents

Cataloged from PDF version of article.Magnetic resonance imaging (MRI) attracts great attention in cellular and molecular imaging due to its non-invasive and multidimensional tomographic capabilities. Development of new contrast agents is necessary to enhance the MRI signal in tissues of interest. Superparamagnetic iron oxide nanoparticles (SPIONs) are used as contrast agents for signal enhancement as they have revealed extraordinary magnetic properties at the nanometre size and their toxicity level is very low compared to other commercial contrast agents. In this study, we developed a new method to functionalize the surface of SPIONs. Peptide amphiphile molecules are used to coat SPIONs non-covalently to provide water solubility and to enhance biocompatibility. Superparamagnetic properties of the peptide-SPION complexes and their ability as contrast agents are demonstrated. In vitro cell culture experiments reveal that the peptide-SPION complexes are biocompatible and are localized around the cells due to their peptide coating

2000 Families: identifying the research potential of an origins - of migration study

Despite extensive recent advances in the empirical and theoretical study of migration, certain critical areas in the analysis of European migration remain relatively underdeveloped both theoretically and empirically. Specifically, we lack studies that both incorporate an origin comparison and trace processes of intergenerational transmission across migrants over multiple generations and incorporating family migration trajectories. This paper outlines the development, data and design of such a study, the 2000 Families study, framed within a theoretical perspective of ?dissimilation? from origins and over generations. We term the study an origins-of-migration study, in that it captures the country of origin, the family origins and potentially the originating causes of migration processes and outcomes. The resulting data comprised nearly 2,000 migrant and non-migrant Turkish families with members across three or more generations, covering. 50,000 individuals. We reflect on the potential of this study for migration research

Anisotropy of ferromagnetism in Co-implanted rutile

Magnetic anisotropy of cobalt implanted single-crystalline rutile has been studied by means of magneto-optical Kerr effect (MOKE) and superconducting quantum interference device (SQUID) techniques. We observed for the first time strong angular dependence of the remanent magnetization and coercive field in the plane of the implanted surface: twofold anisotropy for the (100)-substrate and fourfold anisotropy for the (001)-substrate samples. The observation opens up new possibilities to tailor magnetic anisotropies of the material. Possible origins of ferromagnetism and anisotropies in dielectric and diamagnetic single-crystalline TiO2 samples after Co-ion implantation are discussed. © 2005 IOP Publishing Ltd

Refinement of a Methodology for Untargeted Detection of Serum Albumin Adducts in Human Populations.

Covalently modified blood proteins (e.g., serum albumin adducts) are increasingly being viewed as potential biomarkers via which the environmental causes of human diseases may be understood. The notion that some (perhaps many) modifications have yet to be discovered has led to the development of untargeted adductomics methods, which attempt to capture entire populations of adducts. One such method is fixed-step selected reaction monitoring (FS-SRM), which analyses distributions of serum albumin adducts via shifts in the mass of a tryptic peptide [Li et al. (2011) Mol. Cell. Proteomics 10, M110.004606]. Working on the basis that FS-SRM might be able to detect biological variation due to environmental factors, we aimed to scale the methodology for use in an epidemiological setting. Development of sample preparation methods led to a batch workflow with increased throughput and provision for quality control. Challenges posed by technical and biological variation were addressed in the processing and interpretation of the data. A pilot study of 20 smokers and 20 never-smokers provided evidence of an effect of smoking on levels of putative serum albumin adducts. Differences between smokers and never-smokers were most apparent in putative adducts with net gains in mass between 105 and 114 Da (relative to unmodified albumin). The findings suggest that our implementation of FS-SRM could be useful for studying other environmental factors with relevance to human health

Rapidly progressive glomerulonephritis in a child with Henoch-Schönlein Vasculitis and familial Mediterranean fever

Henoch-Schonlein Vasculitis (HSV) is systemic small vessel vasculitis involving the skin, kidney, joints, and gastrointestinal tract. The proportion of patients reported to have renal involvement varies between 20% and 80%. Rapidly progressive glomerulonephritis (RPGN)is rare syndrome in children, characterized by clinical features of glomerulonephritis (GN) and rapid loss of renal function. We present a severe kidney involvement in a 14 year old boy with HSV in who is carring MEFV mutation. A 14 year old boy had developed sudden onset of palpable purpuric rash on his extensor surfaces of lower extremities. He had elevated an erythrocyte sedimentation rate (ESR) (45 mm/h), C-reactive protein (3.74 mg/dl), serum urea 66 mg/dl, serum creatinine 1.8 mg/dl. Also, he had hypocomplementemia. Antinuclear antibody, anti ds DNA, antineutrophil cytoplasmic antibody, anticardiolipine antibodies were negative. Urinalysis revealed macroscopic hematuria and proteinuria with a 24-h urinary protein excretion of 55 mg/m2/h. The renal biopsy specimen showed crescentic and necrotizing glomerulonephritis. He had also M694V/E148Q compound heterozygote mutation. Clinical symptoms and renal failure resolved with intermittant hemodialysis and medical therapy

An ECVAG† trial on assessment of oxidative damage to DNA measured by the comet assay

The increasing use of single cell gel electrophoresis (the comet assay) highlights its popularity as a method for detecting DNA damage, including the use of enzymes for assessment of oxidatively damaged DNA. However, comparison of DNA damage levels between laboratories can be difficult due to differences in assay protocols (e.g. lysis conditions, enzyme treatment, the duration of the alkaline treatment and electrophoresis) and in the end points used for reporting results (e.g. %DNA in tail, arbitrary units, tail moment and tail length). One way to facilitate comparisons is to convert primary comet assay end points to number of lesions/106 bp by calibration with ionizing radiation. The aim of this study was to investigate the inter-laboratory variation in assessment of oxidatively damaged DNA by the comet assay in terms of oxidized purines converted to strand breaks with formamidopyrimidine DNA glycosylase (FPG). Coded samples with DNA oxidation damage induced by treatment with different concentrations of photosensitizer (Ro 19-8022) plus light and calibration samples irradiated with ionizing radiation were distributed to the 10 participating laboratories to measure DNA damage using their own comet assay protocols. Nine of 10 laboratories reported the same ranking of the level of damage in the coded samples. The variation in assessment of oxidatively damaged DNA was largely due to differences in protocols. After conversion of the data to lesions/106 bp using laboratory-specific calibration curves, the variation between the laboratories was reduced. The contribution of the concentration of photosensitizer to the variation in net FPG-sensitive sites increased from 49 to 73%, whereas the inter-laboratory variation decreased. The participating laboratories were successful in finding a dose–response of oxidatively damaged DNA in coded samples, but there remains a need to standardize the protocols to enable direct comparisons between laboratories

Plasma BDNF Levels Vary in Relation to Body Weight in Females

Brain derived neurotrophic factor (BDNF) has been implicated in the pathophysiology of depression as well as neuropsychiatric and neurodegenerative disorders. Recent studies show a role of BDNF in energy metabolism and body weight regulation. We examined BDNF levels in plasma and cerebrospinal fluid (CSF) samples from age matched elderly depressed and control subjects. Also, the association of BDNF levels with age, gender, body weight, body mass index (BMI), and cognitive performance was evaluated. We did not find any significant differences in plasma and CSF BDNF levels between depressed and control subjects. Plasma BDNF levels were negatively correlated with age (but not with BMI and body weight), when analyses were performed including both depressed and control subjects. A significant reduction in plasma BDNF levels was observed in females as compared to male subjects, and the change in BDNF levels were significantly and positively related to body weight in females. Furthermore, significant increases in Total Recall and Delayed Recall values were found in females as compared to males. In conclusion, the lower BDNF levels observed in females suggest that changes in peripheral BDNF levels are likely secondary to an altered energy balance. However, further studies using larger sample size are warranted