2,762 research outputs found

    The combined use of corticotomy and clear aligners: a case report

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    OBJECTIVE:   To describe an orthodontic treatment that combines an esthetic approach (clear aligners) with surgery (alveolar corticotomy). MATERIALS AND METHODS:   A patient with moderate dental crowding and Class I skeletal and molar relationships was selected. Orthodontic records of the patient were taken. Periodontal indexes, oral health-related quality of life (OHRQoL), and treatment time were evaluated. After we reflected a full-thickness flap beyond the teeth apices, the cortical bone was exposed on the buccal aspect and a modified corticotomy procedure was performed. Interproximal corticotomy cuts were extended through the entire thickness of the cortical layer, just barely penetrating into medullary bone. Orthodontic force was applied on the teeth immediately after surgery. RESULTS:   Total treatment time was 2 months. Periodontal indexes were improved after correction of crowding. A deterioration of OHRQoL was limited to 3 days following surgery. CONCLUSION:   This case report may encourage the use, limited to selected cases, of corticotomy associated with clear aligners to treat moderate crowding

    STAT3, a hub protein of cellular signaling pathways, is triggered by ÎČ-hexaclorocyclohexane

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    Background: Organochlorine pesticides (OCPs) are widely distributed in the environment and their toxicity is mostly associated with the molecular mechanisms of endocrine disruption. Among OCPs, particular attention was focused on the effects of ÎČ-hexaclorocyclohexane (ÎČ-HCH), a widely common pollutant. A detailed epidemiological study carried out on exposed population in the “Valle del Sacco” found correlations between the incidence of a wide range of diseases and the occurrence of ÎČ-HCH contamination. Taking into account the pleiotropic role of the protein signal transducer and activator of transcription 3 (STAT3), its function as a hub protein in cellular signaling pathways triggered by ÎČ-HCH was investigated in different cell lines corresponding to tissues that are especially vulnerable to damage by environmental pollutants. Materials and Methods: Human prostate cancer (LNCaP), human breast cancer (MCF-7 and MDA-MB 468), and human hepatoma (HepG2) cell lines were treated with 10 ”M ÎČ-HCH in the presence or absence of specific inhibitors for different receptors. All samples were subjected to analysis by immunoblotting and RT-qPCR. Results and Conclusions: The preliminary results allow us to hypothesize the involvement of STAT3, through both its canonical and non-canonical pathways, in response to ÎČ-HCH. Moreover, we ascertained the role of STAT3 as a master regulator of energy metabolism via the altered expression and localization of HIF-1α and PKM2, respectively, resulting in a Warburg-like effect

    New high-performance liquid chromatography-dad method for analytical determination of arbutin and hydroquinone in rat plasma

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    Natural substances present in herbal preparations should be carefully used because they can give toxic or therapeutic effects despite of their amount or the way of administration. The safety of products of vegetable origin must be assessed before commercialisation by monitoring the active ingredients and their metabolites. This study was therefore designed to identify and quantify arbutin and its metabolite hydroquinone, naturally present in Arctostaphylos uva-ursi (L.) Spreng plant in rat plasma, after an acute and subacute administration of aqueous arbutin solution in Wistar rats. For this purpose a reversed-phase high-performance liquid chromatography coupled with photodiode array detection was developed to assess the pharmacokinetic of arbutin and hydroquinone in plasma of female rats treated with aqueous arbutin solutions. The detection (arbutin: 0.0617 ”g/ml and hydroquinone 0.0120 ”g/ml) and quantification (arbutin: 0.2060 ”g/ml and hydroquinone: 0.0400 ”g/ml) limits were determined. At the arbutin concentration level of 10.7 ”g/ml repeatability was 13.33% and its recovery 93.4±6.93%, while at the hydroquinone concentration level of 10.6 ”g/ml repeatability was 11.66% and its recovery 92.9±7.75%. Furthermore the method was fully validated and the obtained data indicate that the new method provides good performances

    A ring galaxy at z=1 lensed by the cluster Abell 370

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    We present a study of a very peculiar object found in the field of the cluster-lens Abell 370. This object displays, in HST imaging, a spectacular morphology comparable to nearby ring-galaxies. From spectroscopic observations at the CFHT, we measured a redshift of z=1.062z=1.062 based on the identification of [O ii] 3727 \AA and [Ne v] 3426 \AA emission lines. These emission lines are typical of starburst galaxies hosting a central active nucleus and are in good agreement with the assumption that this object is a ring-galaxy. This object is also detected with ISO in the LW2 and LW3 filters, and the mid Infra-Red (MIR) flux ratio favors a Seyfert 1 type. The shape of the ring is gravitationally distorted by the cluster-lens, and most particularly by a nearby cluster elliptical galaxy. Using the cluster mass model, we can compute its intrinsic shape. Requiring that the outer ring follows an ellipse we put constraints on the M/L ratio of the nearby galaxy and derive a magnification factor of 2.5 ±\pm 0.2. The absolute luminosities of the source are then $L_B = 1.3 \ 10^{12} L_{B \odot}and and \nuL L_\nu \simeq 4. 10^{10}L L_\odot$ in the mid-IR.Comment: 5 pages, 5 figures, uses aa.cls, accepted to A&A Letters. Minor changes, Figure 1 revisited and typos adde

    Accelerated tests on Si and SiC power transistors with thermal, fastand ultra-fast neutrons

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    Neutron test campaigns on silicon (Si) and silicon carbide (SiC) power MOSFETs and IGBTs were conducted at the TRIGA (Training, Research, Isotopes, General Atomics) Mark II (Pavia, Italy) nuclear reactor and ChipIr-ISIS Neutron and Muon Source (Didcot, U.K.) facility. About 2000 power transistors made by STMicroelectronics were tested in all the experiments. Tests with thermal and fast neutrons (up to about 10 MeV) at the TRIGA Mark II reactor showed that single-event burnout (SEB) failures only occurred at voltages close to the rated drain-source voltage. Thermal neutrons did not induce SEB, nor degradation in the electrical parameters of the devices. SEB failures during testing at ChipIr with ultra-fast neutrons (1-800 MeV) were evaluated in terms of failure in time (FIT) versus derating voltage curves according to the JEP151 procedure of the Joint Electron Device Engineering Council (JEDEC). These curves, even if scaled with die size and avalanche voltage, were strongly linked to the technological processes of the devices, although a common trend was observed that highlighted commonalities among the failures of different types of MOSFETs. In both experiments, we observed only SEB failures without single-event gate rupture (SEGR) during the tests. None of the power devices that survived the neutron tests were degraded in their electrical performances. A study of the worst-case bias condition (gate and/or drain) during irradiation was performed

    Efeito de espécies vegetais em bordadura em cebola sobre a densidade populacional de tripes e sirfídeos predadores.

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    Analisou-se a relação entre o efeito do plantio de diferentes espĂ©cies vegetais, em bordadura, na cultura da cebola, Allium cepa L, na incidĂȘncia de Thrips tabaci Lind. e sirfĂ­deos predadores, Toxomerus spp. O experimento foi conduzido na Epagri, EE de Ituporanga, de agosto a dezembro de 1998. Os tratamentos foram cebola em monocultivo; cebola + trigo mourisco (Fagopyrum esculentum Moench); cebola + nabo forrageiro (Raphanus sativus L. var. oleiferus Metzg.); cebola + cenoura (Daucus carota L., cv. Nantes e cv. BrasĂ­lia); cebola + milho (Zea mays L.); cebola + rĂșcula (Eruca sativa L.) + vegetação espontĂąnea. O plantio de diferentes espĂ©cies vegetais em bordadura nĂŁo provocou diferenças significativas na incidĂȘncia de tripes e sirfĂ­deos predadores. A produtividade comercial de bulbos de cebola foi similar em sistema de monocultivo e diversificado, sugerindo ser possĂ­vel adotar tais sistemas sem perdas em rendimento

    New XMM-Newton observation of the Phoenix cluster: properties of the cool core

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    (Abridged) We present a spectral analysis of a deep (220 ks) XMM-Newton observation of the Phoenix cluster (SPT-CL J2344-4243), which we also combine with Chandra archival ACIS-I data. We extract CCD and RGS X-ray spectra from the core region to search for the signature of cold gas, and constrain the mass deposition rate in the cooling flow which is thought to be responsible of the massive star formation episode observed in the BCG. We find an average mass deposition rate of M˙=620(−190+200)stat(−50+150)systM⊙\dot M = 620 (-190 +200)_{stat} (-50 +150)_{syst} M_\odot/yr in the temperature range 0.3-3.0 keV from MOS data. A temperature-resolved analysis shows that a significant amount of gas is deposited only above 1.8 keV, while upper limits of the order of hundreds of M⊙M_\odot/yr can be put in the 0.3-1.8 keV temperature range. From pn data we obtain M˙=210(−80+85)stat(−35+60)systM⊙\dot M = 210 (-80 +85)_{stat} ( -35 +60)_{syst} M_\odot/yr, and the upper limits from the temperature-resolved analysis are typically a factor of 3 lower than MOS data. In the RGS spectrum, no line emission from ionization states below Fe XXIII is seen above 12A˚12 \AA, and the amount of gas cooling below ∌3\sim 3 keV has a best-fit value M˙=122−122+343\dot M = 122_{-122}^{+343} M⊙M_{\odot}/yr. In addition, our analysis of the FIR SED of the BCG based on Herschel data provides SFR=(530±50)M⊙SFR = (530 \pm 50) M_\odot/yr, significantly lower than previous estimates by a factor 1.5. Current data are able to firmly identify substantial amount of cooling gas only above 1.8 keV in the core of the Phoenix cluster. While MOS data analysis is consistent with values as high as M˙∌1000\dot M \sim 1000 within 1σ1 \sigma, pn data provide M˙<500M⊙\dot M < 500 M_\odot yr−1^{-1} at 3σ3\sigma c.l. at temperature below 1.8 keV. At present, this discrepancy cannot be explained on the basis of known calibration uncertainties or other sources of statistical noise.Comment: A&A in press, typos corrected, revised text according to published versio

    A New Bi-Functional Derivative of Polyethylene Glycol as Molecular Carrier for Eugenol and Ibuprofen

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    Eugenol (EU) and ibuprofene (IBU) were covalently bound to a bi-functionalized PEG, used as molecular carrier of drugs and the release kinetics of the two bioactive molecules was studied in vitro in buffer solution at pH 7.4, in simulated gastric fluid and in mouse plasma. The hydrolysis studies showed a specific cleavage dependent on the pH of the medium and by the presence of proteolytic enzymes in mouse plasma. Studies in vitro on the release of the parent drug from this double prodrug in various media, indicate that the adduct may be sufficiently stable to pass intact the gastrointestinal tract and release into the circulation EU and IBU. Many advantages may be achieved by the synthesis of the prodrug EU-PEG-IBU related to synergistic analgesic and anti-inflammatory effects, to the reduction of the adverse reactions and the improvement of the chemical-physical properties of the parent drugs
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