Problems of ranking and dynamics of complex bipartite networks

openA recent new line of research that aims to couple network theory and economics has grown in the last decade, thanks to its ability to capture information from large datasets of exports and cast it into human-readable measures to rank nations and commodities. With Economic Complexity, we aim to infer as much as possible meaningful information about the nodes of the network of worldwide exports and, possibly, use this information to deduce the future topology of the economic network. In this thesis, we will present a new algorithm to measure the complexity of nations and the ubiquity of products, based on a self-consistent use of the Shannon entropy function that makes full use of the exports dataset information. We will discuss how these new entropic measures differ from the usually used complexity measures in the economic complexity framework, such as Fitness and Economic Complexity Index (ECI), highlighting the improvements. An original discussion about the dynamics of the measure will be presented, constructing an entropy-income plane by coupling the entropic complexity measure to some macroeconomic monetary indicator. A coarse-grained analysis of the plane will unveil a flow structure, individuating a laminar dynamics region thanks to the entropic dimension of nations. Moreover, we will observe how entropy and economic stability are strongly correlated. Finally, we will use the dynamical information of the entropy-income plane to predict Gross Domestic Product (GDP) growth at five years. We will use an algorithm developed in the context of Fitness, the selective predictability scheme bootstrap. This algorithm is an example of the method of analogues, firstly developed in the context of atmospheric prediction, as we will look at historical dynamics of nations with comparable entropy and GDP, hence at the analogues, to infer future growth. However, in the original formulation of the algorithm the problem to choose the right ”comparable” nations’ dynamics was not addressed. We will individuate and solve this problem using a statistical learning approach to historical data, combined with an update of the algorithm towards kernel regression. The use of the maximum information available in the dataset of exports, their stability against noisy data, the relevant dynamical information, and the improvement in accuracy of a 20% with respect to the International Monetary Fund prediction of growth make this measure an excellent candidate to rank nations and products according to their relevance in the trade market

The myloglossus muscle: anatomical and clinical observations

The myloglossus muscle is considered an anomalous muscle among the extrinsic muscle of the tongue. In the past, only few Authors provided an anatomical description of the myloglossus muscle (Valenti, 1925; Jude, 1973; Gruber, 1980) and recently a description of myloglossus muscle in Japanese cadaver was reported (Nakajima and Nakamura, 2008). Dissection studies showed that the myloglossus muscle arises from the inner surface of the mandible between the alveolar process and the distal part of the mylohyoid groove and inserts into the tongue root, joining the palatoglossus muscle. Some anatomical variations regarding its origin could be present: it could originate from stylomandibular ligament or partially replace the styloglossus muscle. In patients, with discrete muscle trophism, the myloglossus muscle provides a lateral to medial mucosal fold in the posterior portion of the sublingual sulcus that is evident when the tongue is controlaterally moved. On the contrary, in patients with poor muscle trophism these mucosal folds were not observed. The myloglossus muscle acts primarily as an antagonist of both the controlateral muscle and other muscles that move the tongue toward the opposite side; moreover, it acts together with the controlateral and the palatoglossus muscle, determining the upward movements of the tongue and pharynx, especially in the last phase of deglutition. Its location should be considered to well determine the distal lingual extension of the removable prosthesis. Gruber W. 1880. Uber den musculus myloglossus bei mangel und vorkommen des styloglossus. Arch Path Anat Physiol Klin Med 81:453-457. Jude HD. 1973. Anatomiche untersuchungen uber extensionmoglichkeiten unterer total prothesen im retromolaren raum. Dtsch Zahnarztl Z 28:486. Nakajima K, Nakamura M. Rare case of myloglossus in Japanese cadaver: anatomical and developmental considerations. Anat Sci Int. 2008; 83: 1-5 Valenti G. 1925. Sur un muscle mandibulo-glosse (M. Mylo-Glossus Wood). Arch Ital Biol 75: 77

Epithelial expression of vanilloid and cannabinoid receptors: a potential role in burning mouth syndrome pathogenesis

Burning mouth syndrome is an intraoral burning sensation in which the oral mucosa has a normal appearance and no medical or dental causes can be found. It remains an unknown disease for which long-term treatment is still lacking. The aim of this study is to assess in epithelial human tongue the expression of three receptors involved in pain transmission, such as a transient receptor potential vanilloid receptor type 1 (TRPV1) which mediates the sensation produced by chilli peppers, cannabinoid receptors type 1 (CB1) and type 2 (CB2), which are pathway-related to TRPV1. Epithelial cells express TRPV1, CB1 and CB2 receptors suggesting a role for these cells in sensory transduction. The study was performed on 8 healthy and 9 BMS patients. All patients underwent a 3-mm punch biopsy at the anterolateral aspect of the tongue close to the tip. Specimens were included in paraffin and serially cut to obtain 6um thick sections. The sections were processed for TRPV1, CB1 and CB2 immunohistochemistry. The analysis showed an altered expression of the studied receptors. In particular we observed an increase of TRPV1, a decrease of CB1 and an increase of CB2 expression in epithelial cells of the tongue with a change in morphological localization. So, these receptors seem to be correlated with BMS. These data could be useful for future characterization of BMS markers and specific therapies

Different preparation of Sodium-DNA for bone tissue regeneration

Current strategies for bone tissue regeneration involve the use of a wide range of biomaterials and synthetic bone substitutes; among them, Sodium-DNA could represent a new chance considering its osteoinductive properties (Nakamura et al., 2000; Bowler et a., 2001; Guizzardi et al., 2003; Guizzardi et al., 2007). The aim of this study was to evaluate the regenerative properties of two different preparation of Sodium- DNA (paste or liquid form) in a rat calvarial defect model. The cranium of each rat was shaved and a skin incision from the naso-frontal area to the external occipital protuberance was performed. The skin and the subcutaneous tissues were reflected to expose the full extent of the calvaria. Full-thickness 5X8 mm bone skull defects were made on each parietal region using piezoelectric surgery. Bone defects were filled with Sodium-DNA (paste or liquid form, Veritas, Brescia, Italy) alone or mixed with Bio-Oss (Geistlich, Wolhusen, Switzerland). Histomorphometric evaluation of bone regeneration was performed at the end of the treatments. The data obtained showed a time-dependent active bone healing process; however, differences in the use of past or liquid form were evident. These results suggest that Sodium-DNA could be considered an active biomaterial in bone regeneration, but an adequate formulation to obtain a better regenerative efficacy is needed

TGF-beta1 and VEGF after fresh frozen bone allograft insertion inoral-maxillo-facial surgery

Bone regeneration technique using allografts is widely used in oral surgery to repair alveolar defects and to increase alveolar volume for endosseous implant insertions. Bone allografts promote the reabsorption and neo-synthesis of bone tissue, which are regulated by numerous cytokines, proteins and growth factors. In this study, six patients with insufficient alveolar volume for endosseous implant insertions, were treated with bone regeneration technique using Fresh Frozen Bone (FFB) allografts collected from the femoral head or the hip. Samples of bone graft collected during graft insertion surgery and biopsies collected six months later during implantology were fixed, decalcified and analyzed histomorphologically and morphometrically by haematoxylin-eosin staining. In addition, TGF-beta1 and VEGF were analyzed by immunohistochemistry. The histological analysis of FFBs showed wide areas of calcified bone organized in osteons intermingled with areas of non-calcified matrix containing osteoblasts. However, the regenerated alveolar bone, collected six months after the graft insertion surgery, showed wide areas of non-calcified matrix. TGF-beta1 and VEGF were less expressed in FFB than in regenerated alveolar bone

In vitro effects of Red LED Light on human epidermal keratinocytes: a skin regeneration strategy.

The Red LED (light-emitting diode) light is a promising approach for skin regeneration. Even if its mechanism of action is not clearly understood, its regenerative properties have been investigated since about ten years ago. Keratinocytes represent the first and primary target of this technology because of they are involved in epidermal reconstitution. In these experiments, a new treatment, named “Dermodinamica” (Elisor, Milan), with a wavelength of 630nm, has been used. Different factors produced by keratinocytes have a key role in skin regenerative process: transforming growth factor-b1 (TGF-b1) with a crucial role in maintaining skin homeostasis and in re-epithelialization but also the modulation of metalloproteinases (MMP), in particular 1 and 8, during extracellular matrix production. Moreover, ROS-detoxifying enzymes, such as superoxide dismutase 1 (SOD-1) and heme-oxygenase 1 (HO-1), have an important role in cutaneous wound repair. The aim of the present in vitro study was to evaluate the effect of Red LED light (Dermodinamica, Elisor, Milan) on normal human epidermal keratinocytes (NHEK) after 1 day and 3 days of exposition monitoring: cell viability using MTT assay; TGF-1 production using ELISA kit; expression of collagen type I, MMP-1, MMP-8, SOD-1 and HO-1, using immunohistochemical technique; morphological evaluation analyzing semi-fine sections. Moreover, short (15 min exposition) and prolonged (30 min exposition) treatments were investigated. The results showed an increase of cell viability with the short treatment (15 min of exposition) and a modulation of TGF-b1, ROS-detoxifying enzymes, metalloproteinases. Morphological data confirm the induction of cell cycle physiological progression of keratinocytes. These data indicate a positive role of Red LED light in promoting keratinocytes renewal

Growth factors, CD34 positive cells, and fibrin network analysis in concentrated growth factors fraction

An interesting clinical option for optimizing healing tissue is the use of platelet concentrate. Platelets contain high quantities of growth factors, among these TGF-??1 and VEGF, which are known to be implicated in tissue regeneration. CGF is produced by processing blood samples with a special centrifuge device; three layers are formed: top acellular plasma (PPP), middle CGF and bottom red blood cells (RBC) layers. Given that to date there are no data concerning the biological characteristic of CGF, the aim of this study was to evaluate the presence of TGF-??1 and VEGF in CGF and also in PPP and RBC layers. In addition, since circulating stem cells are recruited from blood to injured tissue for healing we also evaluated the presence of CD34 positive cells. Our data show the presence of TGF-??1 and VEGF in CGF and RBC layers. In addition, we show CD34 positive cells in CGF

Sodium-DNA for Bone Tissue Regeneration: An Experimental Study in Rat Calvaria

Surgical techniques in dental and maxillofacial surgery request fast bone tissue regeneration, so there is a significant need to improve therapy for bone regeneration. Several studies have recently underlined the importance of nucleotides and nucleosides to increase cell proliferation and activity; in particular, the ability of polydeoxyribonucleotide (PDRN) to induce growth and activity of human osteoblasts was demonstrated. Sodium-DNA is the deoxyribonucleic acid (DNA) extracted from the gonadic tissue of male sturgeon and then purified, depolymerized, and neutralized with sodium hydroxide. To date, there are no evidences about the use of Sodium-DNA for bone tissue regeneration. Consequently, our question is about the efficacy of Sodium-DNA in bone healing. For testing the role of Sodium-DNA in bone healing we used a rat calvarial defect model. Sodium-DNA at different concentrations used alone or in association with Fibrin and/or Bio-Oss was used for healing treatments and the bone healing process was evaluated by histomorphometric and immunohistochemical analyses. Our results suggested a positive effect of Sodium-DNA in bone regeneration, providing a useful protocol and a model for the future clinical evaluation of its osteogenic properties

Vestnik statistiki : ezemesjacnyj teoreticeskij naucno-prakticeskij zurnal Gosudarstvennogo Komiteta SSSR po Statistike

Chaperones are the primary regulators of the proteostasis network and are known to facilitate protein folding, inhibit protein aggregation, and promote disaggregation and clearance of misfolded aggregates inside cells. We have tested the effects of five chaperones on the toxicity of misfolded oligomers preformed from three different proteins added extracellularly to cultured cells. All the chaperones were found to decrease oligomer toxicity significantly, even at very low chaperone/protein molar ratios, provided that they were added extracellularly rather than being overexpressed in the cytosol. Infrared spectroscopy and site-directed labeling experiments using pyrene ruled out structural reorganizations within the discrete oligomers. Rather, confocal microscopy, SDS-PAGE, and intrinsic fluorescence measurements indicated tight binding between oligomers and chaperones. Moreover, atomic force microscopy imaging indicated that larger assemblies of oligomers are formed in the presence of the chaperones. This suggests that the chaperones bind to the oligomers and promote their assembly into larger species, with consequent shielding of the reactive surfaces and a decrease in their diffusional mobility. Overall, the data indicate a generic ability of chaperones to neutralize extracellular misfolded oligomers efficiently and reveal that further assembly of protein oligomers into larger species can be an effective strategy to neutralize such extracellular species