Preventive hygiene protocol of University of Milan for women during pregnancy: A qualitative and quantitative bacterial plaque analysis prospective original study

Introduction: The aim of this article is to describe the preventive hygiene protocol of University of Milan for women during pregnancy analyzing the bacterial plaque quantitatively and qualitatively. Materials and methods: A sample of 35 pregnant women following a protocol of periodic visits starting from the first month of pregnancy until the childbirth and in follow up controls were analyzed. Several samples (n = 4) of bacterial plaque for quantitative and qualitative analysis were taken, from the lingual surface of the lower first molar, during the first visit (T0), during the first trimester (T1), during the second or third trimester of pregnancy (T2), and one month after childbirth (T3). Results: By performing a quantitative analysis, it was calculated that the average plaque index (Fig. 1) was n = 48.1% (T0), n = 14.7% (T1), n = 18.4% (T2) and n = 18.9% (T3). The plaque index score presents a downward trend, passing from 48.1% (T0) to 18.9% (T3). The number of total cocci (Fig. 2) was n = 205.39 (T0), n = 57.5(T1), n = 74.6 (T2) and n = 75.4(T3). The number of total bacilli (Fig. 3) was n = 62.7 (T0), n = 23.1 (T1), n = 25.3 (T2), n = 27.1(T3). The total values of cocci and bacilli were correlated and the average trend of the various samples was calculated. By performing a qualitative analysis, the value of G+ cocci (Fig. 5) was n = 2.7 (T0), n = 1.4 (T1), n = 1.4 (T2) and n = 1.5 (T3). The value of G 12 cocci (Fig. 5) was n = 2.3 (T0), n = 0.7 (T1), n = 1.1 (T2) and n = 1.1 (T3). The value of G+ bacilli (Fig. 6) was n = 1.6 (T0), n = 0.9 (T1), n = 1.2 (T2) and n = 1.2 (T3). The value of G 12 bacilli (Fig. 6) was n = 1.3 (T0), n = 0.3 (T1), n = 0.7 (T2) and n = 0.7 (T3). Conclusions: The preventive hygiene protocol used in the Dental Hygiene Department of the University of Milan, during the gestation period, is a suitable method for the control of the bacterial plaque. A considerably decrease of the plaque index and bacterial components between the first visit and the subsequent check-ups was calculated

Vapor etching to avoid micro-masking by gas-bubbles in wet release of MEMS

We report on the formation of gas bubbles during the release of MEMS devices using buffered oxide etch. Several approaches to mitigate the problem are proposed and tested together with a qualitative study of the phenomenon. The chemical reaction behind such phenomenon and the influence of defects and topography is discussed. Finally, a comparison with the HF-vapor release technique is shown

HECT E3 Ligases : a Tale With Multiple Facets

Ubiquitination plays a pivotal role in several cellular processes and is critical for protein degradation and signaling. E3 ubiquitin ligases are the matchmakers in the ubiquitination cascade, responsible for substrate recognition. In order to achieve selectivity and specificity on their substrates, HECT E3 enzymes are tightly regulated and exert their function in a spatially and temporally controlled fashion in the cells. These characteristics made HECT E3s intriguing targets in drug discovery in the context of cancer biology

Ancoraggio in ortodonzia: Revisione della letteratura

Objectives: Anchorage is resistance to an unwanted dental movement. The aim of this study is to analyze the biologic background for a correct control of the anchorage and to evaluate the different kinds of anchorage depending on the movement to be obtained. Materials and methods: A systematic revision of the literature on orthodontic anchorage has been done on US National Library of Medicine on Medline database (www.ncbi.nim.nih.gov/pubmed). Keywords chosen were: "orthodontic and anchorage". Fifteen articles were chosen: the full texts were evaluated. Results: A good anchorage depends on the cellular activity of the periodontal system. From a biologic point of view the best anchorage is seen when there are no changes in the periodontal turn over. This can be obtained when the forces acting on the periodontal ligament and on the periodontal bone do not exceed the threshold promoting a dental movement. Conclusions: The aim of the biomechanical forces is to minimize the unwanted side effects and to maximize the desired dental movements

A novel ubiquitin mark at the N-terminal tail of histone H2As targeted by RNF168 ubiquitin ligase

Ubiquitination of histones plays a critical role in the regulation of several processes within the nucleus, including maintenance of genome stability and transcriptional regulation. The only known ubiquitination site on histones is represented by a conserved Lys residue located at the C terminus of the protein. Here, we describe a novel ubiquitin mark at the N-terminal tail of histone H2As consisting of two Lys residues at positions 13 and 15 (K13/K15). This "bidentate" site is a target of the DNA damage response (DDR) ubiquitin ligases RNF8 and RNF168. Histone mutants lacking the K13/K15 site impair RNF168- and DNA damage-dependent ubiquitination. Conversely, inactivation of the canonical C-terminal site prevents the constitutive monoubiquitination of histone H2As but does not abolish the ubiquitination induced by RNF168. A ubiquitination-defective mutant is obtained by inactivating both the N- and the C-terminal sites, suggesting that these are unique, non-redundant acceptors of ubiquitination on histone H2As. This unprecedented result implies that RNF168 generates a qualitatively different Ub mark on chromatin

Electrode-dependent asymmetric conduction mechanisms in K0.5Na0.5NbO3 micro-capacitors

The ultimate performance of devices employing lead-free piezoelectrics is determined not only by the intrinsic properties of the piezo, but also by processes and materials employed to create the electric contacts. In this paper, we investigate the impact of different metallic electrodes with increasing chemical reactivity (Pt, Ni, Ti, Cr), on the asymmetric behavior of the leakage current in M/K0.5Na0.5NbO3/Pt(111) micro-capacitors, where M stands for the top metallic electrode. For all electrodes we found a marked leakage asymmetry that we ascribed to the presence of a Schottky-like rectifying junction at the M/K0.5Na0.5NbO3/Pt(111) bottom interface, while the corresponding junction at the top interface is deeply affected by the creation of oxygen vacancies due to oxygen scavenging during the growth of the top metallic electrodes, leading to an almost ohmic top contact. The leakage increases with the reactivity of the electrodes, while the asymmetry decreases, thus suggesting that the creation of the top metal/K0.5Na0.5NbO3 interface generates oxygen vacancies diffusing down to the bottom interface and impacting on the rectifying behavior of the Schottky-like junction. Noteworthy, this asymmetric conduction can reflect in an asymmetric piezoelectric and ferroelectric behavior, as a sizable portion of the applied voltage drops across the rectifying junction in reverse bias, thus hampering symmetric bipolar operation, especially in leaky materials

Quantum Poincar\'e Recurrences

We show that quantum effects modify the decay rate of Poincar\'e recurrences P(t) in classical chaotic systems with hierarchical structure of phase space. The exponent p of the algebraic decay P(t) ~ 1/t^p is shown to have the universal value p=1 due to tunneling and localization effects. Experimental evidence of such decay should be observable in mesoscopic systems and cold atoms.Comment: revtex, 4 pages, 4 figure

Clathrin light chain A drives selective myosin VI recruitment to clathrin-coated pits under membrane tension

Clathrin light chains (CLCa and CLCb) are major constituents of clathrin-coated vesicles. Unique functions for these evolutionary conserved paralogs remain elusive, and their role in clathrin-mediated endocytosis in mammalian cells is debated. Here, we find and structurally characterize a direct and selective interaction between CLCa and the long isoform of the actin motor protein myosin VI, which is expressed exclusively in highly polarized tissues. Using genetically-reconstituted Caco-2 cysts as proxy for polarized epithelia, we provide evidence for coordinated action of myosin VI and CLCa at the apical surface where these proteins are essential for fission of clathrin-coated pits. We further find that myosin VI and Huntingtin-interacting protein 1-related protein (Hip1R) are mutually exclusive interactors with CLCa, and suggest a model for the sequential function of myosin VI and Hip1R in actin-mediated clathrin-coated vesicle budding

Quantum Poincare Recurrences for Hydrogen Atom in a Microwave Field

We study the time dependence of the ionization probability of Rydberg atoms driven by a microwave field, both in classical and in quantum mechanics. The quantum survival probability follows the classical one up to the Heisenberg time and then decays algebraically as P(t) ~ 1/t. This decay law derives from the exponentially long times required to escape from some region of the phase space, due to tunneling and localization effects. We also provide parameter values which should allow to observe such decay in laboratory experiments.Comment: revtex, 4 pages, 4 figure