Safety and efficacy of granulocyte–colony-stimulating factor administration following autologous intramuscular implantation of bone marrow mononuclear cells: a randomized controlled trial in patients with advanced lower limb ischemia

Background aimsThe aim was to investigate the therapeutic effect of granulocyte–colony-stimulating factor (G-CSF) administration following implantation of autologous bone marrow mononuclear cells (BM MNC) for patients with lower limb ischemia.MethodsThe design was a randomized controlled trial. Fifteen patients with severe chronic limb ischemia were treated with autologous BM MNC [without G-CSF (MNC–G-CSF) or combined with G-CSF administration for 5 days following transplantation (MNC+G-CSF)].ResultsAll clinical parameters, including ankle brachial index, visual analog scale and pain-free walking distance, showed a mean improvement from baseline, which was measured at 4 and 24 weeks after transplantation in both groups. However, in three (20%) patients, the clinical course did not improve and limb salvage was not achieved. No significant difference was observed among the patients treated in the MNC–G-CSF and MNC+G-CSF groups. No severe adverse reactions were reported during the study period. No relationship was observed between both the numbers of viable MNC or CD34⁺ cells and the clinical outcome.ConclusionsAutologous transplantation of BM MNC into ischemic lower limbs is safe, feasible and efficient for patients with severe peripheral artery disease. However, the administration of G-CSF following cell transplantation does not improve the effect of BM MNC implantation and therefore would not have any beneficial value in clinical applications of such cases.     

Amperometric detection of insulin at renewable sol-gel derived carbon ceramic electrode modified with nickel powder and potassium octacyanomolybdate(IV)

A renewable three-dimensional chemically modified carbon ceramic electrode (CCE) containing nickel powder and K4[Mo(CN)8] was constructed by sol-gel technique. The electrochemical properties and stability of modified electrode was evaluated by cyclic voltammetry in pH range 4-10. The redox couple of [Mo(CN)8] (4-/3-) was shown both as a solute in electrolyte solution and as a component of a carbon based conducting composite electrode. The apparent electron transfer rate constant (ks) and transfer coefficient (alpha) were determined by cyclic voltammetry and they were about 17.1 and 0.57 s(-1), respectively. The catalytic activity of the modified CCE toward insulin oxidation was investigated at pH range of 3-8 by cyclic votammetry. The modified electrode showed excellent electrocatalytic activity toward insulin electroxidation at physiological pH value. The modified electrode was used for insulin detection chronoamperometrically at pH 7. Under optimized condition in amperometry method, the concentration calibration range, detection limit and sensitivity were 0.5-500 nM, 0.45 nM and 6140 nA/microM, respectively. Flow injection amperometric determination of insulin at pH 7.4, at this modified electrode yielded a calibration curve with the following characteristics, linear dynamic range 100-500 pM; sensitivity 8.1 nA/nM and detection limit 40 pM (based on S/N = 3). The inherent stability at wide pH range, high sensitivity, low detection limit, low cost and ease of preparation are of advantageous of this insulin sensor. This sensor indicates great promise for monitory insulin in chromatographic effluents.     

Dynamic response of intraocular pressure and biomechanical effects of the eye considering fluid-structure interaction

The vibration characteristics of shell structures such as eyes have been shown to vary with intraocular pressure (IOP). Therefore, vibration characteristics of the eye have the potential to provide improved correlation to IOP over traditional IOP measurements. As background to examine an improved IOP correlation, this paper develops a finite element model of an eye subject to vibration. The eye is modeled as a shell structure filled with inviscid pressurized fluid in which there is no mean flow. This model solves a problem of a fluid with coupled structural interactions of a generally spherically shaped shell system. The model is verified by comparing its vibrational characteristics with an experimental modal analysis of an elastic spherical shell filled with water. The structural dynamic effects due to change in pressure of the fluid are examined. It is shown that the frequency response of this fluid-solid coupled system has a clear increase in natural frequency as the fluid pressure rises. The fluid and structure interaction is important for accurate prediction of system dynamics. This model is then extended to improve its accuracy in modeling the eye by including the effect of the lens to study corneal vibration. The effect of biomechanical parameters such as the thicknesses of different parts of the eye and eye dimensions in altering measured natural frequencies is investigated and compared to the influence of biomechanical parameters in Goldmann applanation tonometry models. The dynamic response of the eye is found to be less sensitive to biomechanical parameters than the applanation tonometry model.     

Pharmacological AMP Kinase Activators Target the Nucleolar Organization and Control Cell Proliferation

Aims

Phenformin, resveratrol and AICAR stimulate the energy sensor 5′-AMP activated kinase (AMPK) and inhibit the first step of ribosome biogenesis, de novo RNA synthesis in nucleoli. Nucleolar activities are relevant to human health, because ribosome production is crucial to the development of diabetic complications. Although the function of nucleoli relies on their organization, the impact of AMPK activators on nucleolar structures is not known. Here, we addressed this question by examining four nucleolar proteins that are essential for ribosome biogenesis.

Methods

Kidney cells were selected as model system, because diabetic nephropathy is one of the complications associated with diabetes mellitus. To determine the impact of pharmacological agents on nucleoli, we focused on the subcellular and subnuclear distribution of B23/nucleophosmin, fibrillarin, nucleolin and RPA194. This was achieved by quantitative confocal microscopy at the single-cell level in combination with cell fractionation and quantitative Western blotting.

Results

AMPK activators induced the re-organization of nucleoli, which was accompanied by changes in cell proliferation. Among the compounds tested, phenformin and resveratrol had the most pronounced impact on nucleolar organization. For B23, fibrillarin, nucleolin and RPA194, both agents (i) altered the nucleocytoplasmic distribution and nucleolar association and (ii) reduced significantly the retention in the nucleus. (iii) Phenformin and resveratrol also increased significantly the total concentration of B23 and nucleolin.

Conclusions

AMPK activators have unique effects on the subcellular localization, nuclear retention and abundance of nucleolar proteins. We propose that the combination of these events inhibits de novo ribosomal RNA synthesis and modulates cell proliferation. Our studies identified nucleolin as a target that is especially sensitive to pharmacological AMPK activators. Because of its response to pharmacological agents, nucleolin represents a potential biomarker for the development of drugs that diminish diabetic renal hypertrophy.     

No Evidence of Persisting Unrepaired Nuclear DNA Single Strand Breaks in Distinct Types of Cells in the Brain,Kidney, and Liver of Adult Mice after Continuous Eight-Week 50 Hz Magnetic Field Exposure with Flux Density of 0.1 mT or 1.0 mT

Background

It has been hypothesized in the literature that exposure to extremely low frequency electromagnetic fields (50 or 60 Hz) may lead to human health effects such as childhood leukemia or brain tumors. In a previous study investigating multiple types of cells from brain and kidney of the mouse (Acta Neuropathologica 2004; 107: 257–264), we found increased unrepaired nuclear DNA single strand breaks (nDNA SSB) only in epithelial cells of the choroid plexus in the brain using autoradiographic methods after a continuous eight-week 50 Hz magnetic field (MF) exposure of adult mice with flux density of 1.5 mT.

Methods

In the present study we tested the hypothesis that MF exposure with lower flux densities (0.1 mT, i.e., the actual exposure limit for the population in most European countries, and 1.0 mT) shows similar results to those in the previous study. Experiments and data analysis were carried out in a similar way as in our previous study.

Results

Continuous eight-week 50 Hz MF exposure with 0.1 mT or 1.0 mT did not result in increased persisting unrepaired nDNA SSB in distinct types of cells in the brain, kidney, and liver of adult mice. MF exposure with 1.0 mT led to reduced unscheduled DNA synthesis (UDS) in epithelial cells in the choroid plexus of the fourth ventricle in the brain (EC-CP) and epithelial cells of the cortical collecting duct in the kidney, as well as to reduced mtDNA synthesis in neurons of the caudate nucleus in the brain and in EC-CP.

Conclusion

No evidence was found for increased persisting unrepaired nDNA SSB in distinct types of cells in the brain, kidney, and liver of adult mice after continuous eight-week 50 Hz magnetic field exposure with flux density of 0.1 mT or 1.0 mT.     

Evaluation of NUF2 and GMNN Expression in Prostate Cancer: Potential Biomarkers for Prostate Cancer Screening

Background:Prostate cancer (PC) is one of the most abundant cancers among men, and In Iran, has been responsible for 6% of all deaths from cancer in men. NUF2 and GMNN genes are considered as loci of susceptibility to tumorigenesis in humans. Alterations in expression of these genes have been reported in various malignancies. The aim of our study was to test whether different NUF2 and GMNN expression levels are associated with PC incidence and hence, might be considered as new molecular tools for PC screening.Methods:Biopsy samples from 40 PC patients and 41 healthy Iranian men were used to determine the relative gene expression. After RNA extraction and cDNA synthesis, samples were analyzed using TaqMan Quantitative Real time PCR. Patients’ background information, included smoking habits and family histories of PC, were recorded. Stages and grades of their PC were classified by the TNM tumor, node, metastasis (TMN) staging system based on standard guidelines.Results:NUF2 expression did not significantly differ between the groups, while GMNN expression was significantly greater in the PC specimens than in the controls.Conclusion:Regarding the significant role of GMNN in various tumor phenotypes, and its importance in PC progression, the alteration in GMNN expression in PC samples vs. controls indicate that the genetic profiling of this cancer might be considered to personalize therapy for each patient in the future.Key Words: Family history, Geminin (GMNN), Tumor staging, NUF2, Prostate cancer     

Enhanced Thermal Stability and Biocompatibility of Gold Nanorods by Graphene Oxide

In the present study, the effect of nanosized graphene oxide layer on thermal stability and biocompatibility of gold nanorods has been examined. The graphene oxide-wrapped gold nanorods were prepared by electrostatic interaction between negatively charged graphene oxide and positively charged nanorods. The resulting nanohybrids were then heated at different time intervals to 95 °C in a water bath to assess the effect of heat on the rods morphology. The structural changes in gold nanorods were monitored via UV-Vis spectroscopy measurements and transmission electron microscopy images. In similar experiments, the graphene oxide used to wrap gold nanorods was reduced by ascorbic acid in a 95 °C water bath. Our results indicate that while bare gold nanorods are highly vulnerable to elevated temperatures, graphene oxide and reduced graphene oxide-coated gold nanorods remain thermally stable with no structural changes. We also confirmed that the enhanced thermal stability is highly dependent on the concentration of deposited graphene oxide available on the surface of the gold nanorods. In addition, we performed an MTT (3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazoliumbromide) assay to make a comparison between the cytotoxicity of the nanohybrids and their primary building blocks on human dermal fibroblast cells as a normal cell line. We found evidence that graphene oxide can enhance the biocompatibility of the rods through covering toxic chemicals on the surface of them.

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Ni-hemin metal–organic framework with highly efficient peroxidase catalytic activity: toward colorimetric cancer cell detection and targeted therapeutics

Background

Given the great benefits of artificial enzymes, a simple approach is proposed via assembling of Ni²⁺ with hemin for synthesis of Ni-hemin metal–organic-frameworks (Ni-hemin MOFs) mimic enzyme. The formation of the Ni-hemin MOFs was verified by scanning electron microscopy, Transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Energy-dispersive X-ray spectroscopy and UV–vis absorption spectroscopy. This novel nanocomposite exhibited surprising peroxidase like activity monitored by catalytic oxidation of a typical peroxidase substrate, 3,3,5,5′-tetramethylbenzidine, in the presence of H₂O₂. By using folic acid conjugated MOF nanocomposite as a recognition element, we develop a colorimetric assay for the direct detection of cancer cells.

Results

The proposed sensor presented high sensitivity and selectivity for the detection of human breast cancer cells (MCF-7) and Human Caucasian gastric adenocarcinoma. By measuring UV–vis absorbance response, a wide detection range from 50 to 10⁵ cells/mL with a detection limit as low as 10 cells/mLwas reached for MCF-7 cells. We further discuss therapeutics efficiency of Ni-hemin MOFs in the presence of H₂O₂ and ascorbic acid. Peroxidase-mimic Ni-hemin MOFs as reactive oxygen species which could damage MCF-7 cancer cells, however for normal cells (human embryonic kidney HEK 293 cells) killing effect was negligible.

Conclusions

Based on these behaviors, the developed method offers a fast, easy and cheap assay for the interest in future diagnostic and treatment application.