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31.
Shruti Vidhawan Agarwalla Kassapa Ellepola Nikolaos Silikas AH Castro Neto Chaminda Jayampath Seneviratne Vinicius Rosa 《Dental materials》2021,37(2):370-377
ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics. 相似文献
32.
TRA Lane HM Moore IJ Franklin AH Davies 《Annals of the Royal College of Surgeons of England》2015,97(2):e18-e20
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae. 相似文献
33.
Jennifer VanderWeele Teresa Pollack Diana Johnson Oakes Colleen Smyrniotis Vidhya Illuri Priyathama Vellanki Kevin OLeary Jane Holl Grazia Aleppo Mark E. Molitch Amisha Wallia 《Journal of diabetes and its complications》2018,32(7):650-654
Aims
This study validated enterprise data warehouse (EDW) data for a cohort of hospitalized patients with a primary diagnosis of diabetic ketoacidosis (DKA).Methods
247 patients with 319 admissions for DKA (ICD-9 code 250.12, 250.13, or 250.xx with biochemical criteria for DKA) were admitted to Northwestern Memorial Hospital from 1/1/2010 to 9/1/2013. Validation was performed by electronic medical record (EMR) review of 10% of admissions (N?=?32). Classification of diabetes type (Type 1 vs. Type 2) and DKA clinical status were compared between the EMR review and EDW data.Results
Key findings included incorrect classification of diabetes type in 5 of 32 (16%) admissions and indeterminable classification in 5 admissions. DKA was not present, based on the review, in 11 of 32 (34%) admissions. DKA was not present, based on biochemical criteria, in 15 of 32 (47%) admissions.Conclusions
This study found that EDW data have substantial errors. Some discrepancies can be addressed by refining the EDW query code, while others, related to diabetes classification and DKA diagnosis, cannot be corrected without improving clinical coding accuracy, consistency of medical record documentation, or EMR design. These results support the need for comprehensive validation of data for complex clinical populations obtained through data repositories such as the EDW. 相似文献34.
Hannah V. Oakes Shannon Ketchem Alexis N. Hall Tucker Ensley Kristen M. Archibald Brooks B. Pond 《Pharmacological reports : PR》2019,71(6):1289-1292
BackgroundMethylphenidate (Ritalin®) is a psychostimulant used chronically to treat attention deficit hyperactivity disorder. Methylphenidate acts by preventing the reuptake of dopamine and norepinephrine, resulting in an increase in these neurotransmitters in the synaptic cleft. Excess dopamine can be autoxidized to a quinone that may lead to oxidative stress. The antioxidant, glutathione helps to protect the cell against quinones via conjugation reactions; however, depletion of glutathione may result from excess quinone formation. Chronic exposure to methylphenidate appears to sensitize dopaminergic neurons to the Parkinsonian toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We hypothesized that oxidative stress caused by the autooxidation of the excess dopamine renders dopaminergic neurons within the nigrostriatal pathway to be more sensitive to MPTP.MethodsTo test this hypothesis, male mice received chronic low or high doses of MPH and were exposed to saline or MPTP following a 1-week washout. Quinone formation in the striatum was examined via dot blot, and striatal GSH was quantified using a glutathione assay.ResultsIndeed, quinone formation increased with increasing doses of methylphenidate. Additionally, methylphenidate dose-dependently resulted in a depletion of glutathione, which was further depleted following MPTP treatment.ConclusionsThus, the increased sensitivity of dopamine neurons to MPTP toxicity following chronic methylphenidate exposure may be due to quinone production and subsequent depletion of glutathione. 相似文献
35.
Esra PAMUK?U GüVEN Mehmet Emir YALVA? Mehmet Baybora KAYAHAN Hakk? SUNAY Fikrettin ?AH?N Gündüz BAYIRLI 《Journal of applied oral science : revista FOB》2013,21(4):351-357
Objective
The aim of this study was to compare the cytotoxic effects of endodontic cements on human tooth germ stem cells (hTGSCs). MTA Fillapex, a mineral trioxide aggregate (MTA)-based, salicylate resin containing root canal sealer, was compared with iRoot SP, a bioceramic sealer, and AH Plus Jet, an epoxy resin-based root canal sealer.Material and Methods
To evaluate cytotoxicity, all materials were packed into Teflon rings (4 mmµ3 mm) and co-cultured with hTGSCs with the aid of 24-well Transwell permeable supports, which had a pore size of 0.4 µm. Coverslips were coated with MTA Fillapex, iRoot SP and AH Plus Jet and each coverslip was placed onto the bottom of one well of a six-well plate for scanning electron microscopy (SEM) analysis. Before the cytotoxicity and SEM analysis, all samples were stored at 37ºC and at 95% humidity and 5% CO2 for 24 hours to set. The cellular viability was analyzed using MTS test (3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium). The cytotoxic effects and SEM visualization of the tested materials were analyzed at 24-hour, 72-hour, one-week and two-week periods.Results
On the 1st day, only MTA Fillapex caused cytotoxicity compared to negative control (NC) group (p<0.008). No significant difference was observed between the other tested materials at this period (p>0.05). After 14 days of incubation with the test materials, MTA Fillapex exhibited significantly higher cytotoxicity compared with iRoot SP, AH Plus Jet and the NC group (P<0.008). In the SEM analysis, the highest levels of cell attachment were observed for iRoot SP and the control group. After 24 hours, MTA Fillapex reduced the number of cells attached to the surface.Conclusions
Within the limitations of this study, sealers exerted different cytotoxic effects on hTGSCs. Although all materials have exerted cellular toxicity, iRoot SP and AH Plus Jet may promote better attachment to hTGSCs. 相似文献36.
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38.
Robotics in otolaryngology and head and neck surgery: Recommendations for training and credentialing: A report of the 2015 AHNS education committee,AAO‐HNS robotic task force and AAO‐HNS sleep disorders committee
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Neil D. Gross MD F. Christopher Holsinger MD J. Scott Magnuson MD Umamaheswar Duvvuri MD PhD Eric M. Genden MD Tamer AH. Ghanem MD PhD Kathleen L. Yaremchuk MD David Goldenberg MD Matthew C. Miller MD Eric J. Moore MD Luc GT. Morris MD James Netterville Gregory S. Weinstein MD Jeremy Richmon MD 《Head & neck》2016,38(Z1):E151-E158
39.
Sarah A. Rydell Rachael M. Turner Tessa A. Lasswell Simone A. French J. Michael Oakes Brian Elbel Lisa J. Harnack 《Journal of the Academy of Nutrition and Dietetics》2018,118(2):294-300
Background
Policy makers are considering changes to the Supplemental Nutrition Assistance Program (SNAP). Proposed changes include financially incentivizing the purchase of healthier foods and prohibiting the use of funds for purchasing foods high in added sugars. SNAP participant perspectives may be useful in understanding the consequences of these proposed changes.Objective
To determine whether food restrictions and/or incentives are acceptable to food benefit program participants.Design
Data were collected as part of an experimental trial in which lower-income adults were randomly assigned to one of four financial food benefit conditions: (1) Incentive: 30% financial incentive on eligible fruits and vegetables purchased using food benefits; (2) Restriction: not allowed to buy sugar-sweetened beverages, sweet baked goods, or candies with food benefits; (3) Incentive plus Restriction; or (4) Control: no incentive/restriction. Participants completed closed- and open-ended questions about their perceptions on completion of the 12-week program.Participants/setting
Adults eligible or nearly eligible for SNAP were recruited between 2013 and 2015 by means of events or flyers in the Minneapolis/St Paul, MN, metropolitan area. Of the 279 individuals who completed baseline measures, 265 completed follow-up measures and are included in these analyses.Statistical analysis
χ2 analyses were conducted to assess differences in program satisfaction. Responses to open-ended questions were qualitatively analyzed using principles of content analysis.Results
There were no statistically significant or meaningful differences between experimental groups in satisfaction with the program elements evaluated in the study. Most participants in all conditions found the food program helpful in buying nutritious foods (94.1% to 98.5%) and in buying the kinds of foods they wanted (85.9% to 95.6%). Qualitative data suggested that most were supportive of restrictions, although a few were dissatisfied. Participants were uniformly supportive of incentives.Conclusions
Findings suggest a food benefit program that includes incentives for purchasing fruits and vegetables and/or restrictions on the use of program funds for purchasing foods high in added sugars appears to be acceptable to most participants. 相似文献40.