Quantitative analysis of autophagic flux by confocal pH-imaging of autophagic intermediates.

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.

Controlling DNA Bundle Size and Spatial Arrangement in Self-assembled Arrays on Superhydrophobic Surface.

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.

Possible relationship between Al/ferritin complex and Alzheimer's disease.

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.

Inhibitory effect of pituitary adenylate cyclase activating polypeptide on the initial stages of rat follicle development.

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.