FEM analysis of RF breast ablation: Multiprobe versus cool-tip electrode

Background: Radio-frequency ablation (RFA) has recently received much attention as an effective minimally invasive strategy for the local treatment of tumors. The purpose of this study was to evaluate the efficacy of single-needle cool-tip RF breast ablation in terms of temperature distribution and duration of the procedure as compared to multiprobe RF breast ablation. Materials and Methods: Two different commercially available radiofrequency ablation needle electrodes were compared. Finite-element method (FEM) models were developed to simulate the thermoablation procedures. A series of ex vivo radiofrequency thermal lesions were induced to check the response of the FEM calculations. Results: Data obtained from FEM models and from ex vivo procedures showed that cool-tip RF breast ablation assures better performances than multiprobe RF breast ablation in terms of temperature distribution and duration of the procedure. Histopathological analysis of the cool-tip RF thermoablated specimens showed successful induction of coagulation necrosis in the thermoablated specimens. Conclusion: Data obtained from FEM models and from ex vivo procedures suggest that the proposed cool-tip RF breast ablation may kill more tumor cells in vivo with a single application than the multiprobe RF breast ablation

Feasibility and relevance of urine culture during stone fragmentation in patients undergoing percutaneous nephrolithotomy and retrograde intrarenal surgery : a prospective study

Purpose: We evaluated if, during lithotripsy, bacteria may be detected in the irrigation fluid of percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS). The concordance between urine culture from stone fragmentation (SFUC), bladder (BUC), renal pelvic (RPUC) and stone (SC) was analyzed. We also assessed the correlation between variables and cultures and their association with systemic inflammatory response syndrome (SIRS) and of a positive SC. Methods: We included 107 patients who underwent PCNL (n = 53) and RIRS (n = 54) from January 2017 to May 2018. Samples for RPUC were obtained by renal catheterization. Stone fragments and irrigation fluid sample were sent for culture. Results: SFUC was positive in 17 (15.9%), BUC in 22 (20.6%), RPUC in 26 (24.3%) and SC in 30 patients (28%). The concordance between SFUC and SC was the highest among all cultures: 94.1%. SFUC and SC grew identical microorganisms in 15/17 (88.2%) patients. Out of 17 (15.9%) patients with SIRS, 8 (7.5%) had sepsis. SFUC had the highest PPV and specificity to detect positive SC and SIRS. Previous urinary tract infection, a preoperative nephrostomy, stone diameter and composition, staghorn calculi, PCNL, positive BUC, RPUC and SFUC were predictors of infected stone. Variables that indicate complex stones, complex PCNL and an infection of the upper tract were associated with SIRS. Conclusion: SFUC is technically feasible, easy to retrieve and to analyze. The spectrum of SFUC potential application in clinical practice is when is not possible to perform a SC, e.g. complete dusting or during micro-PCNL

Osseointegration of zirconia implants: an SEM observation of the bone-implant interface

Background The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. Methods A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Gottinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Results Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. Conclusion The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level

Effect of microwave sintering on microstructure and mechanical properties in Y-TZP materials used for dental applications

The aim of this work is to study the application of microwave sintering to consolidate yttria-stabilized zirconia polycrystalline (Y-TZP) ceramics commonly applied in dentistry, so as to obtain highly dense materials and fine microstructure with shorter sintering cycles. Three Y-TZP materials are considered: two commercially available for dental applications and one laboratory studied powder. Microwave sintering was carried out at 1200 and 1300 degrees C for 10 min and conventional sintering at 1300 and 1400 degrees C for 2 h. Relative density, Vickers hardness and fracture toughness values for sintered samples were determined. Microwave sintering results, generally, in improved mechanical properties of the materials in terms of hardness and fracture toughness compared to conventional sintering and, in some cases, at lower sintering temperatures. A finer grain microstructure (final grain size < 250 min) was obtained with microwave sintering for both commercial materials. Fracture toughness values differ significantly between sintering techniques and chosen parameters. These results suggest that microwave heating can be employed to sinter Y-TZP commercial ceramics for dental applications obtaining improving the mechanical properties of the materials with a very important time and energy consumption reduction. Crown Copyright (C) 2015 Published by Elsevier Ltd and Techna Group S.r.l. All rights reserved.The authors would like to thank the financial support received from Universidad Politecnica de Valencia under Project 5P20120677 and Ministerio de Economia y Competitividad (MINECO) and co-funded by ERDF (European Regional Development Funds) through the Project (IEC2012-37532-C02-01). A. Borrell acknowledges the Spanish Ministry of Science and Innovation for her Juan de la Cierva Contract (JCI-2011-10498) and the Generalitat Valenciana for the financial support under Project GV/2014/009. A. Presenda acknowledges the Generalitat Valenciana for his Santiago Grisolia program scholarship (GRISOLLV2013/035). The authors would also like to acknowledge Prof. Dr. M. F. Sold from the Faculty of Medicine and Odontology at the Universidad de Valencia for supplying the commercial materials.Presenda, Á.; Salvador Moya, MD.; Penaranda-Foix, FL.; Moreno, R.; Borrell Tomás, MA. (2015). Effect of microwave sintering on microstructure and mechanical properties in Y-TZP materials used for dental applications. Ceramics International. 41(5, Part B):7125-7132. https://doi.org/10.1016/j.ceramint.2015.02.025S71257132415, Part

What is the impact of SARS-CoV-2 pandemic on antimicrobial stewardship programs (ASPs)? The results of a survey among a regional network of infectious disease centres

Discontinuation of antimicrobial stewardship programs (ASPs) and increased antibiotic use were described during SARS-CoV-2 pandemic. In order to measure COVID-19 impact on ASPs in a setting of high multidrug resistance organisms (MDRO) prevalence, a qualitative survey was designed. In July 2021, eighteen ID Units were asked to answer a questionnaire about their hospital characteristics, ASPs implementation status before the pandemic and impact of SARS-CoV-2 pandemic on ASPs after the 1st and 2nd pandemic waves in Italy. Nine ID centres (50%) reported a reduction of ASPs and in 7 cases (38.9%) these were suspended. After the early pandemic waves, the proportion of centres that restarted their ASPs was higher among the ID centres where antimicrobial stewardship was formally identified as a priority objective (9/11, 82%, vs 2/7, 28%). SARS-CoV-2 pandemic had a severe impact in ASPs in a region highly affected by COVID-19 and antimicrobial resistance but weaknesses related to the pre-existent ASPs might have played a role

Universal adhesives applied to deep dentin with different bonding treatments

Fil: Mirotti, Germán. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Lutri, Mónica Paola. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Kraemer, María Elis. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Monserrat, Natalia. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Piconi, María Celeste. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Caballero, Alicia L. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Rozas, Carlos A.. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Croharé, Luis M. Universidad Nacional de Córdoba. Facultad de Odontología. Área de Biología Odontológica; Argentina.Fil: Sezin, Mario. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Eighth-generation adhesives may be applied with total etch, selective-etch or self-conditioning, and serve as primers for non-dental substrates. Aim: To determine the bonding characteristics of universal adhesives applied to the deep pulp wall with different strategies, by means of shear bond strength and laser microscopy. Materials and Method: Cavities 4 mm deep and maximum width were carved in 36 extracted molars. Nine groups were formed according to dental substrate treatment and adhesives, as follows: Total-etch: group 1-Monobond 7 self-etch, group 2-One coat 7 universal, and group 3-Single bond universal; Adamantine etch: group 4-Monobond 7 self-etch, group 5-One coat 7 universal, and group 6-Single bond universal; Self-conditioning: group 7-Monobond 7 self-etch, group 8-One coat 7 universal, and group 9-Single bond universal. Molars were filled following the manufacturer?s instructions. Three specimens per group (27 altogether) were used to determine shear bond strength using a universal testing machine, while layer thicknesses were measured on the remaining specimens using microscope images and Olympus LEXT 3D Software. Analysis of variance was used to compare data. Results: Mean (standard deviation) bond strength in megapascals (MPa) was: group 1: 7.06±3.01; group 2: 10.74±4.36; group 3: 8.20±3.92; group 4: 7.41±2.23; group 5: 6.84±1.50; group 6: 5.86±2.10; group 7: 5.83±1.94; group 8: 7.14±2.37; group 9: 8.06±3.51. Bond strength was higher (p=0.049) for total-etch (8.61±3.96) than for selective etch (6.71±1.98) and self-conditioning (6.91±2.68). No significant difference was found among the three adhesives (p=0.205). Adhesive layer in micrometers (&#956;m) was total-etch 8.71±4.93, selective etch 5.49±1.70 and self-conditioning 6.27±3.01, with no significant difference. Conclusions: There were significant differences among bonding strategies, with the highest values for total-etch. No significant difference was observed between self-conditioning and selective etch. No significant difference was found among the adhesives, which all behaved similarly. The greatest adhesive layer thicknesses were recorded in the total-etch group, with no significant difference among the various adhesive approaches.info:eu-repo/semantics/publishedVersionFil: Mirotti, Germán. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Lutri, Mónica Paola. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Kraemer, María Elis. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Monserrat, Natalia. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Piconi, María Celeste. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Caballero, Alicia L. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Rozas, Carlos A.. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Fil: Croharé, Luis M. Universidad Nacional de Córdoba. Facultad de Odontología. Área de Biología Odontológica; Argentina.Fil: Sezin, Mario. Universidad Nacional de Córdoba. Facultad de Odontología. Departamento de Rehabilitación Bucal. Cátedra de Operatoria I "A”; Argentina.Otras Ciencias de la Salu

Effect of High-Titer Convalescent Plasma on Progression to Severe Respiratory Failure or Death in Hospitalized Patients with COVID-19 Pneumonia: A Randomized Clinical Trial

Importance: Convalescent plasma (CP) has been generally unsuccessful in preventing worsening of respiratory failure or death in hospitalized patients with COVID-19 pneumonia. Objective: To evaluate the efficacy of CP plus standard therapy (ST) vs ST alone in preventing worsening respiratory failure or death in patients with COVID-19 pneumonia. Design, Setting, and Participants: This prospective, open-label, randomized clinical trial enrolled (1:1 ratio) hospitalized patients with COVID-19 pneumonia to receive CP plus ST or ST alone between July 15 and December 8, 2020, at 27 clinical sites in Italy. Hospitalized adults with COVID-19 pneumonia and a partial pressure of oxygen-to-fraction of inspired oxygen (Pao2/Fio2) ratio between 350 and 200 mm Hg were eligible. Interventions: Patients in the experimental group received intravenous high-titer CP (≥1:160, by microneutralization test) plus ST. The volume of infused CP was 200 mL given from 1 to a maximum of 3 infusions. Patients in the control group received ST, represented by remdesivir, glucocorticoids, and low-molecular weight heparin, according to the Agenzia Italiana del Farmaco recommendations. Main Outcomes and Measures: The primary outcome was a composite of worsening respiratory failure (Pao2/Fio2ratio &lt;150 mm Hg) or death within 30 days from randomization. Results: Of the 487 randomized patients (241 to CP plus ST; 246 to ST alone), 312 (64.1%) were men; the median (IQR) age was 64 (54.0-74.0) years. The modified intention-to-treat population included 473 patients. The primary end point occurred in 59 of 231 patients (25.5%) treated with CP and ST and in 67 of 239 patients (28.0%) who received ST (odds ratio, 0.88; 95% CI, 0.59-1.33; P =.54). Adverse events occurred more frequently in the CP group (12 of 241 [5.0%]) compared with the control group (4 of 246 [1.6%]; P =.04). Conclusions and Relevance: In patients with moderate to severe COVID-19 pneumonia, high-titer anti-SARS-CoV-2 CP did not reduce the progression to severe respiratory failure or death within 30 days. Trial Registration: ClinicalTrials.gov Identifier: NCT04716556