An in vitro model of Fusobacterium nucleatum and Porphyromonas gingivalis in single- and dual-species biofilms

Tavares, Livia Jacovassi,Klein, Marlise Inez,Panariello, Beatriz Helena Dias,de Avila, Erica Dorigatti,Pavarina, Ana Claudia Korean Academy of Periodontology 2018 Journal of Periodontal & Implant Science Vol.48 No.1

Purpose: The goal of this study was to develop and validate a standardized in vitro pathogenic biofilm attached onto saliva-coated surfaces. Methods: Fusobacterium nucleatum (F. nucleatum) and Porphyromonas gingivalis (P. gingivalis) strains were grown under anaerobic conditions as single species and in dual-species cultures. Initially, the bacterial biomass was evaluated at 24 and 48 hours to determine the optimal timing for the adhesion phase onto saliva-coated polystyrene surfaces. Thereafter, biofilm development was assessed over time by crystal violet staining and scanning electron microscopy. Results: The data showed no significant difference in the overall biomass after 48 hours for P. gingivalis in single- and dual-species conditions. After adhesion, P. gingivalis in single- and dual-species biofilms accumulated a substantially higher biomass after 7 days of incubation than after 3 days, but no significant difference was found between 5 and 7 days. Although the biomass of the F. nucleatum biofilm was higher at 3 days, no difference was found at 3, 5, or 7 days of incubation. Conclusions: Polystyrene substrates from well plates work as a standard surface and provide reproducible results for in vitro biofilm models. Our biofilm model could serve as a reference point for studies investigating biofilms on different surfaces.

Combination of a new ultrasonic tip with rotary systems for the preparation of flattened root canals

Tavares Karina Ines Medina Carita,Pinto Jáder Camilo,Santos-Junior Airton Oliveira,Esteves Torres Fernanda Ferrari,Guerreiro-Tanomaru Juliane Maria,Tanomaru-Filho Mario 대한치과보존학회 2021 Restorative Dentistry & Endodontics Vol.46 No.4

Objectives This study evaluated 2 nickel-titanium rotary systems and a complementary protocol with an ultrasonic tip and a small-diameter instrument in flattened root canals. Materials and Methods Thirty-two human maxillary second premolars with flattened canals (buccolingual diameter ≥4 times larger than the mesiodistal diameter) at 9 mm from the radiographic apex were selected. The root canals were prepared by ProDesign Logic (PDL) 30/0.01 and 30/0.05 or Hyflex EDM (HEDM) 10/0.05 and 25/0.08 (n = 16), followed by application of the Flatsonic ultrasonic tip in the cervical and middle thirds and a PDL 25/0.03 file in the apical third (FPDL). The teeth were scanned using micro-computed tomography before and after the procedures. The percentage of volume increase, debris, and uninstrumented surface area were analyzed using the Kruskal-Wallis, Dunn, Wilcoxon, analysis of variance/Tukey, and paired and unpaired t-tests (α = 0.05). Results No significant difference was found in the volume increase and uninstrumented surface area between PDL and HEDM (p > 0.05). PDL had a higher percentage of debris than HEDM in the middle and apical thirds (p < 0.05). The FPDL protocol resulted in less debris and uninstrumented surface area for PDL and HEDM (p < 0.05). This protocol, with HEDM, reduced debris in the middle and apical thirds and uninstrumented surface area in the apical third (p < 0.05). Conclusions High percentages of debris and uninstrumented surface area were observed after preparation of flattened root canals. The HEDM, Flatsonic tip, and 25/0.03 instrument protocol enhanced cleaning in flattened root canals.

Pediatric Liver Transplantation: Caregivers' Quality of Life

Tavares, Ana Paula Bastos,Seixas, Lucas Belem Pessoa de Melo Guerra,Jayme, Caren Lopes Wanderlei,Porta, Gilda,Seixas, Renata Belem Pessoa de Melo,Carvalho, Elisa de The Korean Society of Pediatric Gastroenterology 2022 Pediatric gastroenterology, hepatology & nutrition Vol.25 No.6

Purpose: The survival rate of pediatric patients undergoing liver transplantation has increased considerably. Despite this, the period after transplantation is still complex and poses several challenges to the recipient's family, which is responsible for care management. Recently, more attention has been paid to the impact of this complex procedure on the quality of life of caregivers. Hence, this study is aimed at assessing the quality of life of caregivers of patients who have undergone liver transplantation and the aspects that influence it. Methods: This was an observational and cross-sectional study. From November 2020 to January 2021, short-form-36 questionnaires and additional questions were given to the main caregivers of children and adolescents who underwent pediatric liver transplantation. Results: Thirty-eight questionnaires were completed and the results revealed a lower quality of life in comparison to Brazilian standards, primarily in the mental domains (41.8±14.1 vs. 51.1±2.8; p<0.001). It did not show a significant association with socioeconomic or transplant-related factors, but it did show a negative impact on parents' perception of the child's health. Parents who reported worse health status for their children had a lower mental quality of life (44.1±13.8 vs. 33.3±12.6; p<0.05). Conclusion: The caregivers of transplanted children have a lower quality of life than those of the local population. Psychological assistance should be routinely provided to parents for long-term follow-up to mitigate potential negative effects on the transplanted child's care.

Resolving the Kashmir Conflict: Pakistan, India, Kashmiris and Religious Militants

Rodrigo Tavares 서울대학교행정대학원 2008 Asian Journal of Political Science Vol.16 No.3

This article introduces a conflict resolution framework to address the Kashmir1 conflict. Firstly, Kashmir is mapped out as a multi-dimensional dispute between various parties:besides the interstate dispute between India and Pakistan, Kashmir is also an armedconflict both between India and the Kashmiris over the right of self-determination andbetween India and the religious militants who are waging a jihad to create a theocraticstate. Secondly, in order to understand the complexity of Kashmir, I introduce an originalframework based upon six levels of sovereignty that helps us in underscoring theimplications of the bargaining process between India, Pakistan and Kashmir. Based onthis, I propose a roadmap for peace, which comprises three successive steps: confidencebuildingmeasures, restoration of the asymmetric original status of Jammu and Kashmirand, finally, shared sovereignty (partial or total condominium) between India andPakistan.

Breeding and biology of Hypsipyla grandella Zeller (Lepidoptera: Pyralidae) fed with mahogany seeds (Swietenia macrophylla King)

Marcelo Tavares de Castro,Sandro Coelho Linhares Montalvão,Rose Gomes Monnerat 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.1

The shoot borer, Hypsipyla grandella Zeller, is a Lepidopteran that practically covers the entire Brazilian territory. Its damage to mahogany is so intense that it can prevent establishment of commercial plantations of the species. Studies of its control are critical for mahogany planting in different regions to be feasible and sustainable. To conduct bioassays and studies of this insect's biology, mass rearing is necessary. This study aimed to develop a method of mass rearing based on a diet of mahogany seeds. Caterpillars arising from mahogany populations located in Brasilia, Brasil were placed in plastic containers containing mahogany seeds. Morphological and morphometric aspects were evaluated through eight successive generations. The mahogany seeds produced a good supply of quality insects for performance of bioassays, with uniform sizes and weights for each instar and a low adult deformation rate.

Ovarian teratoma removed by laparoscopic ovariectomy in a dog

Inês T. Tavares,Ramón R. Barreno,José P. Sales-Luís,Carlo G. Vaudano 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.6

An elective laparoscopic ovariectomy on a healthy dog revealed a cystic structure in the left ovary. The surgical procedure was successful. Histopathological examination showed the presence of a teratoma adjacent to the ovary. To the best of the authors’ knowledge, this is the first reported case of an ovarian teratoma removed by laparoscopic ovariectomy in a dog by using a multiport laparoscopic ovariectomy technique.

A Systems Engineering Approach for Uncertainty Analysis of a Station Blackout Scenario

J. Ricardo Tavares de Sousa,Aya Diab 한국시스템엔지니어링학회 2019 시스템엔지니어링학술지 Vol.15 No.1

After Fukushima Dai-ichi NPP accident, the need for implementation of diverse and flexible coping strategies (FLEX) became evident. However, to ensure the effectiveness of the safety strategy, it is essential to quantify the uncertainties associated with the station blackout (SBO) scenario as well as the operator actions. In this paper, a systems engineering approach for uncertainty analysis (UA) of a SBO scenario in advanced pressurized water reactor is performed. MARS-KS is used as a best estimate thermal-hydraulic code and is loosely-coupled with Dakota software which is employed to develop the uncertainty quantification framework. Furthermore, the systems engineering approach is adopted to identify the requirements, functions and physical architecture, and to develop the verification and validation plan. For the preliminary analysis, 13 uncertainty parameters are propagated through the model to evaluate the stability and convergence of the framework. The developed framework will ultimately be used to quantify the aleatory and epistemic uncertainties associated with an extended SBO accident scenario and assess the coping capability of APR1400 and the effectiveness of the implemented FLEX strategies.

The influence of nanofillers on the properties of ethanol-solvated and non-solvated dental adhesives

Leonardo Bairrada Tavares da Cruz,Marcelo Tavares Oliveira,Adriano Fonseca Lima 대한치과보존학회 2019 Restorative Dentistry & Endodontics Vol.44 No.3

Objectives: The aim of this study was to evaluate the influence of different concentrations of nanofillers on the chemical and physical properties of ethanol-solvated and non-solvated dental adhesives. Materials and Methods: Eight experimental adhesives were prepared with different nanofiller concentrations (0, 1, 2, and 4 wt%) and 2 solvent concentrations (0% and 10% ethanol). Several properties of the experimental adhesives were evaluated, such as water sorption and solubility (n = 5, 20 seconds light activation), real-time degree of conversion (DC; n = 3, 20 and 40 seconds light activation), and stability of cohesive strength at 6 months (CS; n = 20, 20 seconds light activation) using the microtensile test. A light-emitting diode (Bluephase 20i, Ivoclar Vivadent) with an average light emittance of 1,200 mW/cm2 was used. Results: The presence of solvent reduced the DC after 20 seconds of curing, but increased the final DC, water sorption, and solubility of the adhesives. Storage in water reduced the strength of the adhesives. The addition of 1 wt% and 2 wt% nanofillers increased the polymerization rate of the adhesives. Conclusions: The presence of nanofillers and ethanol improved the final DC, although the DC of the solvated adhesives at 20 seconds was lower than that of the non-solvated adhesives. The presence of ethanol reduced the strength of the adhesives and increased their water sorption and solubility. However, nanofillers did not affect the water sorption and strength of the tested adhesives.

An in vitro model of Fusobacterium nucleatum and Porphyromonas gingivalis in single- and dual-species biofilms

Lívia Jacovassi Tavares,Marlise Inêz Klein,Beatriz Helena Dias Panariello,Erica Dorigatti de Avila,Ana Cláudia Pavarina 대한치주과학회 2018 Journal of Periodontal & Implant Science Vol.48 No.1

Purpose: The goal of this study was to develop and validate a standardized in vitro pathogenic biofilm attached onto saliva-coated surfaces. Methods: Fusobacterium nucleatum (F. nucleatum) and Porphyromonas gingivalis (P. gingivalis) strains were grown under anaerobic conditions as single species and in dual-species cultures. Initially, the bacterial biomass was evaluated at 24 and 48 hours to determine the optimal timing for the adhesion phase onto saliva-coated polystyrene surfaces. Thereafter, biofilm development was assessed over time by crystal violet staining and scanning electron microscopy. Results: The data showed no significant difference in the overall biomass after 48 hours for P. gingivalis in single- and dual-species conditions. After adhesion, P. gingivalis in single- and dual-species biofilms accumulated a substantially higher biomass after 7 days of incubation than after 3 days, but no significant difference was found between 5 and 7 days. Although the biomass of the F. nucleatum biofilm was higher at 3 days, no difference was found at 3, 5, or 7 days of incubation. Conclusions: Polystyrene substrates from well plates work as a standard surface and provide reproducible results for in vitro biofilm models. Our biofilm model could serve as a reference point for studies investigating biofilms on different surfaces.

발전소 정전사고 시나리오를 위한 불확실성 분석

J. Ricardo Tavares de Sousa,Aya Diab 한국전산유체공학회 2019 한국전산유체공학회지 Vol.24 No.4

In the wake of Fukushima Dai-ichi NPP accident, the diverse and flexible coping strategies (FLEX) have been proposed for advanced nuclear reactors to enhance the coping capability of extended station blackout. In this work, the uncertainty analysis is performed to analyze a station blackout for APR1400 nuclear reactor by calculating the key parameters and quantifying the safety margin. APR1400 model was generated using MARS-KS thermal-hydraulic code. 16 uncertain parameters were identified and an uncertainty analysis framework was developed by coupling MARS-KS and Dakota statistical tool. Afterwards, a sensitivity analysis is conducted with core exit temperature and peak cladding temperature selected as safety parameters. For the sensitivity analysis, the accident was split into two phases: before and after the alignment of the FLEX equipment. The major contributors to a higher core exit temperature are: initial pressurizer pressure, initial secondary pressure, reactor power, SIT inventory and SIT temperature. A high safety margin is quantified which demonstrates the robustness of the emergency procedures which contemplates the use of FLEX equipment and TDAFWP to cope with 72 hours of station blackout.