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《Journal of endodontics》2020,46(6):846-857
IntroductionThis study assessed the cleaning, shaping, and disinfection abilities of 2 instrumentation systems in molar root canals using a novel correlative analytical approach.MethodsThe root canals from extracted mandibular and maxillary molars with apical periodontitis were pair matched according to anatomic similarities as determined by micro–computed tomographic analysis and prepared with either XP-endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) (n = 16) or Reciproc Blue (VDW, Munich, Germany) (n = 16) instruments and 2.5% sodium hypochlorite irrigation. Pre- and postpreparation micro–computed tomographic scans were used to identify and calculate the unprepared surface areas (shaping), which were histobacteriologically evaluated for the presence of residual bacteria (disinfection) and pulp tissue remnants (cleaning) in each canal third.ResultsUnprepared canal surface areas for XP-endo Shaper and Reciproc Blue in the full canal length were approximately 26% and 19% (P < .05), respectively (30% and 23% in the apical part of the canal, P > .05). Preparation with Reciproc Blue resulted in 37.5% canals free of bacteria in all sections examined and 56% in the apical sections only. XP-endo Shaper resulted in 44% canals free of bacteria in all sections, and 56% in the apical part of the canal only. Pulp tissue remnants were not observed in 31% (all canal sections) and 50% (apical canal sections) of specimens from both instrument systems. No significant differences were observed between instruments when comparing the amount of pulp tissue remnants and the number of cases negative for bacteria and tissue remnants (P > .05).ConclusionsAlthough the Reciproc Blue instrument had superior shaping ability in comparison with XP-endo Shaper, both systems performed similarly in cleaning and disinfecting root canals. Irregular canals and difficult-to-reach areas were not thoroughly cleaned and disinfected by any of the tested systems. 相似文献
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Andres Eduardo Campuzano-García Bertha Torres-Alvarez Diana Hernández-Blanco 《Journal of cosmetic and laser therapy》2015,17(4):213-215
Hailey–Hailey disease (HHD), also known as benign familial pemphigus, is an autosomal dominant skin condition that affects the adhesion of epidermal keratinocytes. Although the initial manifestation of flaccid vesicles on erythematous or normal skin in flexure sites frequently goes unnoticed, large, macerated, exudative plaques of superficial erosions with crusting are observed at the time of diagnosis. There is no specific treatment for HHD, and most cases are symptomatically supported. However, infrared laser ablation has been somewhat helpful. We present a case successfully treated with fractional CO2 laser showing a long-term favourable outcome and no adverse effects. Thus, this modality could be an alternative to full ablation for this condition. 相似文献
25.
Adolescence is marked by a steep increase in risk-taking behavior. The serious consequences of such heightened risk taking raise the importance of identifying protective factors. Despite its dynamic change during adolescence, family relationships remain a key source of influence for teenagers. Using a longitudinal fMRI approach, we scanned 23 adolescents twice across a 1.5-year period to examine how changes in parent–child relationships contribute to changes in adolescent risk taking over time via changes in adolescents’ neural reactivity to rewards. Results indicate that although parent–child relationships are not associated with adolescent risk taking concurrently, increases in positive parent–child relationships contribute to declines in adolescent risk taking. This process is mediated by longitudinal decreases in ventral striatum activation to rewards during risk taking. Findings highlight the neural pathways through which improvements in positive parent–child relationships serve to buffer longitudinal increases in adolescent risk taking. 相似文献
26.
《Vaccine》2020,38(46):7372-7378
BackgroundTheories of health behavior change are being inadequately adopted to understand the reasons behind low influenza vaccination rates among healthcare workers (HCWs). The Theory of Planned Behavior (TPB) is being used to predict intention-behavior relationship while the Health Belief Model (HBM) is being employed to predict actual behavior. The purpose of this study was to test a conceptual model based on the HBM’s constructs to predict Jordanian HCWs’ intentions for influenza vaccine uptake as an alternative to the TPB.MethodA cross-sectional questionnaire-based study was conducted in 2016 in a tertiary teaching hospital in Amman-Jordan including a convenience sample of 477 HCWs with direct patient contact. The study instrument was tested for validity and reliability. A conceptual regression model was proposed incorporating the constructs of the primary HBM with some modifications in the threat construct as well as an additional variable about explicit past vaccination behavior (in the past year and/or any previous history of influenza vaccine uptake).ResultsAlmost all the constructs of the HBM demonstrated significant differences between participants intending and those who did not intend to vaccinate against influenza. After adjusting for the confounding variables in the final conceptual regression model, past vaccination behavior (OR= 4.50, 95%Confidence Interval 3.38–6.00, P< 0.0005) and the perceived benefit scale (OR= 1.19, 95% Confidence Interval 1.11–1.28, P< 0.0005) were the only significant predictors of intentions to vaccinate against influenza in the next season.ConclusionTaking into consideration the altruistic beliefs of HCWs and their explicit past vaccination history augments the utility of the original HBM tool in predicting HCWs’ intentions to vaccinate against influenza in a way that is consistent with the predictive ability of the Theory of Planned Behavior. 相似文献
27.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases. 相似文献
28.
《Drug metabolism and pharmacokinetics》2020,35(1):56-70
Hepatic uptake mediated by organic anion transporting polypeptide (OATP) 1B1 and 1B3 can serve as a major elimination pathway for various anionic drugs and as a site of drug-drug interactions (DDIs). This article provides an overview of the in vitro approaches used to predict human hepatic clearance (CLh) and the risk of DDIs involving OATP1Bs. On the basis of the so-called extended clearance concept, in vitro–in vivo extrapolation methods using human hepatocytes as in vitro systems have been used to predict the CLh involving OATP1B-mediated hepatic uptake. CLh can be quantitatively predicted using human donor lots possessing adequate OATP1B activities. The contribution of OATP1Bs to hepatic uptake can be estimated by the relative activity factor, the relative expression factor, or selective inhibitor approaches, which offer generally consistent outcomes. In OATP1B1 inhibition assays, substantial substrate dependency was observed. The time-dependent inhibition of OATP1B1 was also noted and may be a mechanism underlying the in vitro–in vivo differences in the inhibition constant of cyclosporine A. Although it is still challenging to quantitatively predict CLh and DDIs involving OATP1Bs from only preclinical data, understanding the utility and limitation of the current in vitro methods will pave the way for better prediction. 相似文献
29.
Puja Vijay Parikh 《International journal of environmental health research》2016,26(4):458-466
Environmental chemical exposure could be an important etiologic factor for geographic differences in breast cancer incidence. In this study, we examined emissions of polycyclic aromatic hydrocarbons (PAHs) and PM2.5 in relation to breast cancer incidence in metro Atlanta and rural Georgia by analyzing data from the Surveillance, Epidemiology, and End Results Program and the Environmental Protection Agency. The results showed that metro Atlanta had a significantly higher age-adjusted annual incidence rate of female breast cancer than rural Georgia (132.6 vs. 113.7 per 100,000) for 1992–2011. Emissions of both PAHs [adjusted β = 0.568 (95 % CI: 0.209, 0.927); p = 0.004] and PM2.5 [adjusted β = 2.964 (95 % CI: 0.468, 5.459); p = 0.023] were significantly associated with breast cancer incidence in metro Atlanta area. This study suggests that ambient air pollution, especially PAHs and PM2.5, could have a significant impact on the increased incidence of female breast cancer in urban areas. 相似文献
30.
《Mayo Clinic proceedings. Mayo Clinic》2019,94(7):1321-1329
Immune checkpoint inhibitors are molecules that increase the endogenous immune response against tumors. They have revolutionized the field of oncology. Since their initial approval for the treatment of advanced melanoma, their use has expanded to the treatment of several other advanced cancers. Unfortunately, immune checkpoint inhibitors have also been associated with the emergence of a new subset of autoimmune-like toxicities, known as immune-related adverse events. These toxicities differ depending on the agent, malignancy, and individual susceptibilities. Although the skin and colon are most commonly involved, any organ may be affected, including the liver, lungs, kidneys, and heart. Most of these toxicities are diagnosed by excluding other secondary infectious or inflammatory causes. Corticosteroids are commonly used for treatment of moderate and severe immune-related adverse events, although additional immunosuppressive therapy may occasionally be required. The occurrence of immune-related toxicities may require discontinuation of immunotherapy, depending on the specific toxicity and its severity. In this article, we provide a focused review to familiarize practicing clinicians with this important topic given that the use of immune checkpoint inhibitors continues to increase. 相似文献