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In this paper we present a simple and robust method to realize highly ordered arrays of stretched and suspended DNA molecules over the millimeter length scale. To this end we used an ad hoc designed superhydrophobic surface made of high aspect-ratio silicon pillars, where we deposited a droplet containing genomic DNA. A precise positioning of DNA strands was achieved by shaping the silicon pillars so that sharpened features resembling tips were included. Such features allowed us to accurately control the droplet de-wetting dynamics, pinning DNA strands in a well-defined position above pillars. The proposed technique has the potential to positively impact on the development of novel DNA chips for genetic analysis. [ABSTRACT FROM AUTHOR]

Many experimental evidences point out the correlation between the presence of aluminum-ferritin complex and neursopathological disorders. In these complexes, two different ranges of Aluminium (Al) atoms are usually found, i.e., just few atoms or several hundreds. Here, we investigated the in-vitro Al-apoferritin binding, with the aim to elucidate the mechanism behind the formation of Al-ferritin complexes in-vivo. To this purpose, we studied the mineralization of Al in its ionic and complexed form with citrate demonstrating that high Al levels found in clinical studies can be obtained only conveying Al by small physiological ligands. [ABSTRACT FROM AUTHOR]

Increased iron concentration in tissues appears to be a factor in the genesis and development of inflammatory and degenerative diseases. By means of real-time small angle x-ray scattering measurements, we studied the kinetics of iron release from the ferritin inorganic core as a function of time and distance from the iron core centre. Accordingly, the iron release process follows a three step model: (i) a defect nucleation in the outer part of the mineral core, (ii) the diffusion of the reducing agent towards the inner part of the core, and (iii) the erosion of the core from the inner to the outer part. [ABSTRACT FROM AUTHOR]

The use of superhydrophobic surfaces (SHSs) is now emerging as an attractive platform for the realization of one-dimensional (1D) nanostructures with potential applications in many nanotechnological and biotechnological fields. To this purpose, a strict control of the nanostructures size and their spatial arrangement is highly required. However, these parameters may be strongly dependent on the complex evaporation dynamics of the sessile droplet on the SHS. In this work, we investigated the effect of the evaporation dynamics on the size and the spatial arrangement of self-assembled 1D DNA bundles. Our results reveal that different arrangements and bundle size distributions may occur depending on droplet evaporation stage. These results contribute to elucidate the formation mechanism of 1D nanostructures on SHSs.

Although numerous techniques have been developed to monitor autophagy and to probe its cellular functions, these methods cannot evaluate in sufficient detail the autophagy process, and suffer limitations from complex experimental setups and/or systematic errors. Here we developed a method to image, contextually, the number and pH of autophagic intermediates by using the probe mRFP-GFP-LC3B as a ratiometric pH sensor. This information is expressed functionally by AIPD, the pH distribution of the number of autophagic intermediates per cell. AIPD analysis reveals how intermediates are characterized by a continuous pH distribution, in the range 4.5-6.5, and therefore can be described by a more complex set of states rather than the usual biphasic one (autophagosomes and autolysosomes). AIPD shape and amplitude are sensitive to alterations in the autophagy pathway induced by drugs or environmental states, and allow a quantitative estimation of autophagic flux by retrieving the concentrations of autophagic intermediates.

Objectives: Ferritin is the main iron-storage protein capable of containing thousands of iron atoms. However, ferritin can bind in vitro other atoms such as aluminum and it has been shown that also in vivo atoms other than iron, as aluminum and zinc, are present in large amounts in ferritin. Since aluminum appears to be involved in the development of Alzheimer's disease, in the present study the specific content of aluminum in ferritin of Alzheimer's patients was analyzed and compared with other control groups., Design and Methods: The content of Fe, Al and Zn of blood ferritin was measured by mass spectrometry in patients with Alzheimer's disease and compared with other clinical and control groups., Results: The results obtained confirm the hypothesis of a functional role of ferritin as a regulatory protein of toxic metals and clearly indicate that ferritin from Alzheimer's patients has a content of aluminum higher than that of controls., Conclusions: The specific aluminum content of ferritin seems to be related to different disease stages of Alzheimer's disease. This result confirms the hypothesis of aluminum as a possible factor inducing the Alzheimer's disease and opens the ways to possible new diagnostic tests., (Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Pituitary adenylate cyclase activating polypeptide (PACAP) is transiently expressed in preovulatory follicles of different species and positively affects parameters correlated with the ovulatory process. It has also been shown to be expressed in the interstitial tissue and in interstitial glandular cells in the proximity of primordial and preantral follicles. The aim of the present study was to investigate whether PACAP influences the recruitment of primordial follicles and the growth and differentiation of preantral follicles. Rat ovaries from 2-day-old animals were cultured for 5 days in the presence of PACAP. This treatment significantly inhibited the primordial to primary follicle transition. PACAP inhibited granulosa cell proliferation without affecting cell viability. PACAP also inhibited the growth of isolated preantral follicles cultured under basal conditions or in the presence of follicle-stimulating hormone (FSH). These results suggest that PACAP is significantly involved in the cyclic recruitment of primordial follicles and in the FSH-dependent growth of preantral follicles., ((c) 2010 Elsevier Ireland Ltd. All rights reserved.)