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1.
Materials (Basel) ; 17(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930376

RESUMO

This is the first study of non-woven fabrics elaborated by melt-blowing from polymer nanocomposites made of Nylon 6 and nanoclay (Cloisite 20A) modified with an amine (1,4 diaminobutane dihydrochloride). Morphological and physical characteristics, adsorption capacity, and antibacterial properties are presented. From the X-ray diffraction (XRD) results, it was possible to observe a displacement of the signals to other 2θ angles, due to an α to ϒ phase shift. The scanning electron microscopy (SEM) images showed that the mean diameter of fiber decreased as the content of nanoclay increased. The mechanical tests showed that the tear strength force of neat nylon was 1.734 N, but this characteristic increased to 2.135 N for the sample with 0.5% modified nanoclay. The inulin adsorption efficiency of the Nylon 6/C20A 1.5% and Nylon 6/C20A 2% samples at 15 min was 75 and 74%, respectively. The adsorption capacity of Nylon 6/C20A 1.5% and Nylon 6/C20A 2% for methylene blue and methyl orange remained above 90% even after four adsorption cycles. In addition, non-woven fabrics present antibacterial activity against E. coli.

2.
Nanomaterials (Basel) ; 12(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36500869

RESUMO

The number of chronic kidney disease (CKD) persons continues to rise in Mexico. They require renal replacement therapy, and in the absence of it, hemodialysis is the major option for their survival. The uremic toxins present in the blood are removed by hemodialysis, which involve membranes. In this study, nonwoven fabrics with modified carbon black nanoparticles in a matrix polymer of Nylon 6 were obtained and evaluated as an adsorbent material of uremic toxins. All nonwoven fabrics were characterized by FTIR, XRD, TGA, SEM, and contact angle measurements and were evaluated as an adsorbent material for the urea toxin and as an albumin retainer. The findings suggest their potential application as a hemodialysis membrane. Nanocomposites had a higher hydrophilic characteristic compared to pure Nylon 6. The average diameter size of the fibers was in the range of 5 to 50 µm. All nanocomposites nonwoven fabrics showed high removal percentages of inulin in a range of 80-85% at 15 min of contact. Most Ny6 Zytel/CB nanocomposites showed a high percentage of urea removal (80 to 90%).

3.
J Fr Ophtalmol ; 45(7): 741-747, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35850884

RESUMO

PURPOSE: Brow ptosis can interfere with blepharoplasty results and can be corrected using several techniques. The present study was performed to compare two techniques for brow suspension, both with concomitant upper eyelid blepharoplasty. METHOD: A prospective, interventional, randomized study involving 27 female patients was performed to compare the effects of two different techniques of brow suspension: eyebrow suspension with nylon thread (ESN) and internal browpexy fixation (IBF), both combined with upper lid blepharoplasty. Qualitative assessment was carried out using a questionnaire, and quantitative angular measurement analysis of the brow position was performed using digital photographs taken with a Vectra H1 camera before, 60, and 120 days after surgery. The data were transferred to an Excel table and statistically analyzed. RESULTS: ESN was performed in 14 patients and IBF in 13 patients. Both groups were homogeneous in terms of age. The main preoperative complaints were excess skin on the upper eyelid (81.4%) and reduced visual field (59.2%) in both groups. Most of the patients expected aesthetic improvement, and the surgical results were considered satisfactory for all of them. There was no significant difference between ESN and IBF in the quantitative evaluation of eyebrow position. CONCLUSION: Both ESN and IBF resulted in a high degree of patient satisfaction. Both techniques provided similar brow suspension, emphasizing that IBF is technically easier to perform and produces less scarring.


Assuntos
Blefaroplastia , Sobrancelhas , Blefaroplastia/efeitos adversos , Blefaroplastia/métodos , Pálpebras/cirurgia , Feminino , Humanos , Estudos Prospectivos , Estudos Retrospectivos
4.
J Comp Physiol B ; 192(3-4): 423-434, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35195757

RESUMO

Physiological trade-offs among expensive fitness-related traits, such as reproduction and immunity, are common in life histories of animals. An immune challenge can have different effects on female reproduction mediated by resource allocation and acquisition. In this study, employing a widely used method to challenge the insect immune system (nylon implant), we assessed the effects of mounting a chronic immune response simulating three successive immune assaults on survival and reproduction of mated females of Gryllus assimilis. We also verified feeding behavior following an implantation, which can be important in explaining trade-off dynamics in terms of energy acquisition. For this, three experimental groups were designed (Control, Sham, and Implant) with oviposition rates, egg morphometry, and nymph vigour observed over 3 weeks, at which ovarian mass and unlaid eggs were quantified from remaining individuals. The results showed that chronic implants were detrimental to female survival and reproduction throughout the experiments; Surgical Sham had no effect on survival compared to the control, but did on reproductive aspects such as oviposition rates and hatchling vigour. These negative effects on reproduction in Sham disappeared in the last experimental week, but still strong in the implanted females. Such immune challenge affected the feeding behavior of implanted females by reducing food consumption compared to control after infection, which is probably explained by illness-induced anorexia that takes place to maximize the immune system performance as a part of sickness behavior, exacerbating the adverse effects observed on reproduction (i.e., fewer and smaller eggs, and low vigour of nymphs) and survival.


Assuntos
Gryllidae , Animais , Comportamento Alimentar , Feminino , Gryllidae/fisiologia , Insetos , Ninfa , Fenótipo , Reprodução/fisiologia
5.
Dent Traumatol ; 38(1): 53-61, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34309197

RESUMO

BACKGROUND/AIM: Splinting is an important procedure after avulsion. However, the role of splint stiffness and extension is not fully understood. The aim of this study was to evaluate the effect of splint stiffness and extensions on the mobility and stress on an injured tooth under physiological biting load. MATERIALS AND METHODS: Three-dimensional (3D) finite element models were created from a cone beam computer tomogram of a patient with normal occlusion. An avulsion injury of the right central incisor was created with a 1000 N load application on the palatal of the injured tooth, causing increased socket width. Splints made from four materials were tested: 0.9 mm diameter wire-composite splint (WCS1), 0.4 mm diameter wire-composite splint (WCS2), 1.0 mm diameter nylon-composite splint (NCS), and a 2 mm high by 0.2 mm thick plastic strip composite splint (PSS). Three splint extensions (involving 6, 5, and 3 teeth) were evaluated. Mobility of the avulsed tooth and the maximum principal stress distributions in the adjacent teeth were calculated. RESULTS: The injured incisor tooth mobility was not affected by the splint extensions. The NCS and PSS stabilized the avulsed incisor but allowed, respectively, 10 and 20 times more mobility under horizontal loading than the WCS1, which inhibited most mobility, while the WCS2 allowed double the mobility compared with WCS1. The NCS and PSS allowed more tooth mobility, mainly in the extrusion direction. Splints were 2-3 times more effective in limiting mobility under intrusive loads than extrusive loads. High levels of stress were found at the base of the composite attachments in the adjacent incisors. CONCLUSION: Splinting an avulsed tooth to one or two teeth bilaterally using a nylon splint or a plastic strip is appropriate for tooth stabilization and should be recommended over the 0.4mm wire-composite splint, while the 0.9 mm orthodontic wire is too rigid and not recommended.


Assuntos
Avulsão Dentária , Mobilidade Dentária , Resinas Compostas , Análise de Elementos Finitos , Humanos , Incisivo , Contenções
6.
Front Med (Lausanne) ; 8: 700793, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513873

RESUMO

Purpose: To compare the performance of nylon sutures to that of polyglactin sutures in pediatric patients undergoing cataract surgery. Setting: University of Campinas (UNICAMP), Campinas, São Paulo, Brazil Design: A prospective, randomized, partially masked, single-site clinical trial. (https://clinicaltrials.gov/ct2/show/NCT03812640). Methods: A total of 80 eyes from 80 patients who underwent pediatric cataract surgery were randomized into two groups in block sizes of four. Group A consisted of 41 patients whose surgical incisions were sutured with polyglactin 10-0 material. Group B consisted of 39 patients whose surgical incisions were sutured with nylon 10-0 material. The primary outcome was frequency of suture-related complications in each group. Secondary outcomes were the frequency with which suture removal was necessary. Results: The incidence of suture-related complications within 6 months of follow up was 0 out of 41 eyes (0.00%) in the polyglactin group and 17 out of 39 eyes (43.59%) in the nylon control group (p < 0.001). In all of the eyes with suture-related complications, the sutures were promptly removed. The most frequent complications were vascularization near the suture (17.95%) and loose sutures (17.95%). No ocular or systemic study-related adverse events were observed. Conclusions: Polyglactin sutures were found to be safe and effective for pediatric patients undergoing cataract surgery. Their lower rate of complications and reduced likelihood of removal (and the subsequent need for general anesthesia) make their use preferrable to that of nylon sutures. This study represents the first controlled randomized clinical trial to compare nylon sutures to polyglactin sutures in pediatric patients undergoing cataract surgery. Clinical Trial Registration: URL: https://clinicaltrials.gov/ct2/show/, Identifier: NCT03812640.

7.
Polymers (Basel) ; 13(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204165

RESUMO

Approximately 200,000 tons of water contaminated with dyes are discharged into effluents annually, which in addition to infectious diseases constitute problems that afflict the population worldwide. This study evaluated the mechanical properties, surface structure, antimicrobial performance, and methylene blue dye-contaminant adsorption using the non-woven fabrics manufactured by melt-blowing. The non-woven fabrics are composed of nylon 6 (Ny 6) and zinc oxide nanoparticles (ZnO NPs). The polymer nanocomposites were previously fabricated using variable frequency ultrasound assisted-melt-extrusion to be used in melt-blowing. Energy dispersion spectroscopy (SEM-EDS) images showed a homogeneous dispersion of the ZnO nanoparticles in nylon 6. The mechanical properties of the composites increased by adding ZnO compared to the nylon 6 matrix, and sample Ny/ZnO 0.5 showed the best mechanical performance. All fabric samples exhibited antimicrobial activity against S. aureus and fungus C. albicans, and the incorporation of ZnO nanoparticles significantly improved this property compared to pure nylon 6. The absorption efficiency of methylene blue (MB), during 60 min, for the samples Ny/ZnO 0.05 and Ny/ZnO 0.25 wt%, were 93% and 65%, respectively. The adsorption equilibrium data obeyed the Langmuir isotherm.

8.
Mar Environ Res ; 169: 105327, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33892337

RESUMO

Plankton organisms, biogenic particles, inorganic mineral particles, and microplastics are the four main components of particulate organic matter in aquatic ecosystems. We propose a new index, the Relative Microplastics Concentration (RMC, in %), considering that microplastics are more deleterious when food is scarce. A total of 112 plankton net samples were collected in estuarine, coastal and shelf environments of Tamandaré, Brazil. Particles were identified by image analysis (ZooScan) and FTIR. Higher concentrations of total microplastics, PP (Polypropylene) and PE (Polyethylene) in the estuary indicate an oceanward decreasing gradient from terrestrial sources. Higher concentrations of nylon fibres were found offshore. Yet, RMC indicated that the Bay had the most severely impacted ecosystems (RMC: 2.4% in the estuary, 5.1% in the Bay, and 2.0% on the shelf), for total microplastics and PP & PE. Shelf ecosystems were most severely impacted with nylon fibres. RMC analysis provided a new perspective into the impact of microplastics on tropical coastal food webs.


Assuntos
Microplásticos , Poluentes Químicos da Água , Brasil , Ecossistema , Monitoramento Ambiental , Plásticos , Poluentes Químicos da Água/análise
9.
Dent Traumatol ; 37(2): 256-263, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33180992

RESUMO

BACKGROUND/AIMS: Traumatic dental injuries are highly prevalent and are considered an important health problem. The aim of this study was to evaluate the in vitro stress distribution around simulated traumatized teeth subjected to different types of splints by photoelastic analysis. MATERIALS AND METHODS: For each group, five models of maxillary and mandibular arches were made in photoelastic resin using prefabricated teeth models, which were fixed and adjusted in a semi-adjustable articulator. All splints were bonded with composite resin on the labial surfaces of the maxillary central incisors, the lateral incisors and the canine teeth, simulating trauma to the 11. The groups were divided according to the type of splint: control-without splint; rigid-brackets and 0.021 × 0.025 inch stainless steel wire; semi-rigid-brackets and 0.016 × 0.016 inch cobalt-chromium wire; fiber-fiberglass ribbon; and flexible-nylon thread. The groups were submitted to an occlusal force in a special device attached to a universal test machine in balanced, protrusive, and lateral occlusions. Then, the incisal edge of the 11 was ground to simulate infra-occlusion, and the tests were performed again. Five points were analyzed around tooth 11 with a polariscope, and the data were submitted to ANOVA and Tukey tests at a 5% level of significance. RESULTS: When centric occlusion was analyzed by comparing normal occlusion to infra-occlusion, all groups showed high stress values in infra-occlusion with statistical differences-except for the control group. When lateral occlusion was analyzed, the nylon splint showed lower statistical differences compared with the control, fiberglass, and rigid splint groups, which did not differ between each other. The semi-rigid splint did not differ from any group. CONCLUSIONS: Fiberglass and semi-rigid splints showed better stress distribution around the traumatized tooth under occlusal loads. The nylon splint showed characteristics of non-stress distribution.


Assuntos
Contenções , Mobilidade Dentária , Resinas Compostas , Humanos , Fios Ortodônticos , Contenções Periodontais
10.
Acta sci. vet. (Impr.) ; 49(supl.1): 731, 2021. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1366375

RESUMO

Background: Hydronephrosis is the dilation of the pelvis and renal calyxes due to post-renal obstruction. The obstruction is often associated with extraluminal masses, blood clots and ureter ligation in castration procedures. Ureter ligation is reported as a malpractice. The renal function is reestablished if ligation is rapidly undone, but not for obstructions longer than four weeks. Often, clinical signs are results from months to years after the castration, when nephrectomy is the best therapeutic option. This paper aims to report a case of asymptomatic unilateral hydronephrosis in a 10-year-old dog caused by chronic ureter occlusion with Nylon 3.0 suture during an elective procedure. Case: A 10-year-old female pinscher dog, spayed 3 years ago was admitted at the Surgery Department of the Veterinary Hospital of the Federal University of Jataí (HV-UFJ). The animal was taken for periodontal treatment. In the physical and laboratory examination (complete blood count, hepatic and renal biochemical tests) no significant and noteworthy alterations were found. Ultrasonographic examination showed no changes in the topography and echotexture of the left kidney, however the right kidney was not visualized, with an anechoic structure suggestive of advanced and severe hydronephrosis. Therefore, exploratory laparotomy was proposed to identify the observed structure, with the periodontal treatment considered for a later time. So, a retroumbilical incision was made, followed by linea alba and the removal of simple isolated suture remaining from previous surgical procedure. In the cavity, the viscera were isolated and the left kidney was identified, observing preserved anatomy. On the other hand, the right kidney had altered topography and morphology, being exposed after release of adhesions in adjacent structures. The right renal artery and vein were dissected and a double ligature was made. Then, the right ureter was dissected, observing marked dilatation in the proximal portion and the presence of local ligation with Nylon 3.0. Right ureterectomy and right nephrectomy were performed. After nephrectomy, the capsule was ruptured, observing dark fluid in it and absence of tissue compatible with renal parenchyma. The material was preserved in 10% formaldehyde and sent for histopathological examination. Histopathology revealed risk of rupture of the renal capsule due to the advance of renal degeneration and complete absence of parenchyma. However, contrary to the severity of the histopathological, surgical and ultrasonographic findings, the patient did not present clinical signs at the time of diagnosis. Discussion: In the intraoperative evaluation, the cause of the hydronephrosis was verified to be in fact the ligation of the ureter, which may have been accidental or due to the malpractice of the veterinarian surgeon. Other possible causes such as adhesions and granulomas were ruled out because the Nylon 3.0 suture was found in the proximal portion of the right ureter. It is believed that the patient may have presented clinical signs of hydronephrosis that may have been confused by the tutors as postoperative complications, changes that if identified and performed in time, could have avoided the occurrence or worsening of hydronephrosis and subsequent nephrectomy. Clinically, the bitch did not show clinical signs presented in the literature as consistent with hydronephrosis such as polyuria, polydipsia, abdominalgia, external fistula and anorexia. Therefore, it is believed that this case is one of the first reports of the occurrence of severe hydronephrosis without typical clinical manifestations of hydronephrosis. This fact raises a warning about the thorough monitoring in the postoperative period by owners and veterinarians, in addition to highlighting concerns regarding the occurrence of medical malpractice versus surgical accidents.


Assuntos
Animais , Feminino , Cães , Obstrução Ureteral/veterinária , Erros Médicos/veterinária , Hidronefrose/cirurgia , Hidronefrose/veterinária , Rim/cirurgia , Ovariectomia/veterinária , Salpingectomia/veterinária , Histerectomia/veterinária , Imperícia , Nefrectomia/veterinária
11.
Rev. med. vet. zoot ; 67(1): 33-41, ene.-abr. 2020. tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1127011

RESUMO

RESUMEN La investigación se realizó a fin de evaluar el efecto del gas de formalina sobre el recuento de mesófilos en nailon comercial (poliamida) destinado a procedimientos quirúrgicos. En primer lugar, se evaluó la contaminación de una muestra del material comercial de 1 g expuesta al ambiente de quirófano por 72 horas, a través de la técnica de recuento en placa para mesófilos; se obtuvieron 850 UFC/g. Una vez comprobada la contaminación de la poliamida comercial, esta se sometió a gases de formalina en comprimidos. Se colocaron 5 muestras (n=5) de nailon de 1 g cada una en 5 recipientes herméticos de 1 litro con 1 gramo de formalina cada uno; estos recipientes se almacenaron en un mueble en sala de esterilización a un metro de altura del piso y posteriormente, fueron abiertos y cultivados a través de la técnica de recuento en placa para mesófilos, uno por día a lo largo de 5 días a intervalos de 24 horas. Los resultados obtenidos no registraron crecimientos de microorganismos a partir de las 24 horas y durante los 5 días posteriores y se encontraron diferencias estadísticamente significativas (p < 0,05). Se concluye que bajo las condiciones del presente estudio el tiempo de esterilización de la formalina sobre nailon comercial es de 24 horas.


ABSTRACT Hie present research work was carried out with the purpose of evaluating the effect of formalin gas on the count of mesophiles in commercial nylon (polyamide) destined to surgical procedures. Firstly, the contamination of a 1 g commercial nylon sample, exposed to the operating room environment for 72 hours, was evaluated through the plate counting technique for mesophiles; it yielded a result of 850 CFU / gram. Once the contamination of the commercial polyamide was checked, it was subjected to formalin gases in tablets. Five nylon samples (n=5) of 1 gram each were placed in 5 1 liter airtight containers containing 1 gram of formalin; Hese containers were stored in a cabinet in the sterilization room one meter above the floor, and later opened and cultivated through the plate counting technique for mesophiles, one per day for 5 days at 24 hour intervals. The results obtained after being exposed to formalin gases in tablets did not register growths of microorganisms after 24 hours and during the 5 days after the study, finding statistically significant differences (p < 0.05) in relation to the studied times concluding under the conditions of the present study that the sterilization time of the formalin on commercial nylon is equal to 24 hours.


Assuntos
Animais , Procedimentos Cirúrgicos Operatórios , Esterilização , Poluição Ambiental , Formaldeído , Gases , Resistência à Seca , Nylons , Salas Cirúrgicas , Pesquisa , Suturas , Comprimidos , Termômetros , Tempo , Bactérias , Toxinas Bacterianas , Contagem de Colônia Microbiana , Abscesso , Temperatura Alta , Inflamação
12.
Indian J Dent Res ; 31(5): 763-767, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33433516

RESUMO

AIM: The aim of this study was to develop an alternative low-cost membrane for use in guided tissue regeneration (GTR). SETTING AND DESIGN: In vitro study. METHODS AND MATERIAL: In this study, a membrane prepared from a 335 mm sized opening nylon substrate, covered in aqueous resin derived from chitosan, was compared with a commercial material, a non-degradable expanded poly (tetrafluoroethylene). Nylon substrate samples 2.0 × 2.0 cm were covered by aqueous resin based on diluted chitosan solution into 1:05 or 1:10 by spin coating technique to produce from 06, 10, and 15 layers. The surfaces of these membranes were observed using optical microscopy. The physical properties were measured by hydration superficial energy measurements (ΔG) and a tensile test machine. STATISTICAL ANALYSIS: Statistical analysis was performed using the Student's t test at a significance level of 5%, using the BioEstat 2.0 program. RESULTS: The Δ G values of the nylon membrane covered by the 1:05 of chitosan with 15 layers were close to the commercial membrane's Δ G values. The tensile strength values of the nylon membrane covered by the 1:05 of chitosan with 15 layers were higher than the commercial membrane's (115.826 MPa, P < 0.05). CONCLUSION: Therefore, the membrane developed shows some favorable physical properties that could qualify it as a material candidate for use in guided tissue regeneration.


Assuntos
Quitosana , Regeneração Tecidual Guiada , Regeneração Óssea , Humanos , Membranas Artificiais , Resistência à Tração
13.
São José dos Campos; s.n; 2020. 86 p. il., graf., tab..
Tese em Português | BBO - Odontologia | ID: biblio-1151413

RESUMO

O uso de próteses fixas adesivas é uma opção de tratamento reabilitador em casos de ausência dentária. A resina composta é um material com boas características mecânicas e estéticas, mas se faz necessário a utilização de reforços para proporcionar maior resistência ao conjunto. O presente estudo teve como objetivo avaliar a carga máxima de fratura quando da utilização de um sistema de reforço de sílica-nylon em próteses fixas adesivas confeccionadas em resina composta indireta. O estudo in vitro simulou uma prótese fixa adesiva de três elementos anterior (A) e posterior (P). Dessa forma, foram confeccionados 80 espécimes distribuídos em 8 grupos experimentais (n=10), tendo como variáveis a presença do sistema de reforço em sílica-nylon (R) e a ciclagem mecânica da peça protética (C). O processo de envelhecimento foi realizado através da ciclagem mecânica por 106 ciclos a 4 Hz (ERIOS ER-11000 Plus, São Paulo, Brasil). As amostras foram submetidas ao ensaio de resistência à carga máxima de fratura na máquina de ensaio universal (EMIC DL 1000, EMIC, Brasil) com uma célula de carga de 1000 Kgf e foram feitas análises das amostras após a fratura em estereomicroscópio (Discovery V20 CarlZeiss, Jena, Alemanha) e Microscopia Eletrônica de Varredura (Inspect S 50, FEI Company, Brno, República Tcheca). A análise estatística foi constituída pela análise de variância (ANOVA) e teste Tukey 5%. O estudo in silico foi realizado através da Análise em Elementos Finitos (FEA), onde os dentes pilares e as próteses foram escaneados (Ceramill Map 400, Amann Girrbach) e transferidos para o software CAD Rhinoceros (version 4.0SR8; McNeel North America, Seattle, WA), para elaboração do modelo volumétrico 3D e posteriormente a análise foi feita através do Software Ansys 19.3 (ANSYS, Inc. Southpointe, Canonsburg, EUA). Os resultados de resistência à carga máxima de fratura foram (N): A=163,55; AC=184,48; AR=198,81; ARC=192,24; P=539,99; PC=359,61; PR=541,74 e PRC=608,74. Foi constatado que houve diferença estatística na presença do reforço tanto nos grupos da região anterior (p=0,025), quanto da região posterior (p=0,001). Os resultados de tensão máxima principal, obtidos no FEA, foram (MPa): A=53,24/122,40; AR=55,07/117,70; P=33,28/36,18 e PR=28,06/42,87. Concluiu-se que a incorporação da malha de sílica-nylon aumentou a resistência à carga máxima de fratura das próteses fixas adesivas, independente da área em que se encontra, e os resultados obtidos no FEA corroboraram com os encontrados no teste in vitro o que permite concluir que houve validação do teste in silico(AU)


The use of resin-bonded fixed dental prostheses is a rehabilitative treatment option in cases of missing teeth. Composite resin is a material with good mechanical and aesthetic characteristics, but it is necessary to use reinforcements to provide greater resistance to the prosthesis. The present study aims to evaluate the maximum fracture load using a silica-nylon reinforcement system on resin-bonded fixed dental prostheses made of indirect composite resin. In vitro test simulated an anterior (A) and posterior (P) three-element resin-bonded fixed dental prostheses. Thus, 80 specimens were made in 8 experimental groups (n = 10), with variables the presence of the silica-nylon reinforcement system (R) and the mechanical cycling of the prosthesis (C). The aging process was performed through mechanical cycling for 106 cycles at 4 Hz (ERIOS ER-11000 Plus, São Paulo, Brazil). The samples were tested by maximum fracture load in the universal test machine (EMIC DL 1000, EMIC, Brazil) with a 1000 Kgf load cell and analyzed by stereomicroscope (Discovery V20 CarlZeiss, Jena, Germany) and Scanning Electron Microscopy (Inspect S 50, FEI Company, Brno, Czech Republic). Statistical analysis consisted of analysis of variance (ANOVA) and Tukey test 5%. In silico study was performed by Finite Element Analysis (FEA), where the abutment teeth and the prostheses were scanned (Ceramill Map 400, Amann Girrbach) and transferred to the CAD Rhinoceros (version 4.0SR8; McNeel North America, Seattle, WA) for the elaboration of the 3D volumetric model and the analysis test was made in the Ansys Software 19.3 (ANSYS, Canonsburg, PA, USA). The results of resistance to the maximum fracture load were (N): A=163,55; AC=184,48; AR=198,81; ARC=192,24; P=539,99; PC=359,61; PR=541,74 and PRC=608,74. It was found that there was a statistical difference in the presence of reinforcement in both the anterior region (p=0,025) and posterior region groups (p=0,001). The maximum main stress results obtained in the FEA were (MPa): A=53,24/122,40; AR=55,07/117,70; P=33,28/36,18 and PR=28,06/42,87. It was concluded that the incorporation of the silica-nylon mesh increased the resistance to maximum fracture load of the resin-bonded fixed dental prostheses regardless of the area it is located, and the results obtained in the FEA corroborated the results of in vitro test, which allows to conclude that the in silico test was validated(AU)


Assuntos
Prótese Adesiva/efeitos adversos , Teste de Materiais/métodos , Resinas Compostas/administração & dosagem , Análise de Elementos Finitos/estatística & dados numéricos , Nylons/análise
14.
Methods Mol Biol ; 1932: 151-157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30701498

RESUMO

Tissue printing and dot blot are simple techniques to detect miRNA expression and localization, allowing a better understanding of the function of a miRNA. In this work, we describe a tissue printing and a dot blot hybridization protocol for miRNA detection and localization in plant tissues, which opens the possibility of analyzing spatiotemporal expression patterns of miRNAs.


Assuntos
Immunoblotting/métodos , Hibridização In Situ/métodos , MicroRNAs/genética , Plantas/genética , RNA de Plantas/genética , Análise Espaço-Temporal
15.
Animal ; 12(1): 54-65, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28554338

RESUMO

Although the conventional in situ ruminal degradability method is a relevant tool to describe the nutritional value of ruminant feeds, its need for rumen-fistulated animals may impose a restriction on its use when considering animal welfare issues and cost. The aim of the present work was to develop a ruminal degradability technique which avoids using surgically prepared animals. The concept was to orally dose a series of porous bags containing the test feeds at different times before slaughter, when the bags would be removed from the rumen for degradation measurement. Bags, smaller than those used in the conventional nylon bag technique, were made from woven nylon fabric, following two shape designs (rectangular flat shape, tetrahedral shape) and were fitted with one of three types of device for preventing their regurgitation. These bags were used in two experiments with individually housed non-pregnant, non-lactating sheep, as host animals for the in situ ruminal incubation of forage substrates. The bags were closed at the top edge by machine stitching and wrapped in tissue paper before oral dosing. Standard times for ruminal incubation of substrates in all of the tests were 4, 8, 16, 24, 48, 72 and 96 h before slaughter. The purpose of the first experiment was to compare the effectiveness of the three anti-regurgitation device designs, constructed from nylon cable ties ('Z-shaped', ARD1; 'double Z-shaped', ARD2; 'umbrella-shaped', ARD3), and to observe whether viable degradation curves could be generated using grass hay as the substrate. In the second experiment, three other substrates (perennial ryegrass, red clover and barley straw) were compared using flat and tetrahedral bags fitted with type ARD1 anti-regurgitation devices. Non-linear mixed-effect regression models were used to fit asymptotic exponential curves of the percentage dry matter loss of the four substrates against time of incubation in the reticulorumen, and the effect of type of anti-regurgitation device and the shape of nylon bag. All three devices were highly successful at preventing regurgitation with 93% to 100% of dosed bags being recovered in the reticulorumen at slaughter. Ruminal degradation data obtained for tested forages were in accordance with those expected from the conventional degradability technique using fistulated animals, with no significant differences in the asymptotic values of degradation curves between bag shape or anti-regurgitation device. The results of this research demonstrate the potential for using a small bag technique with intact sheep to characterise the in situ ruminal degradability of roughages.


Assuntos
Fibras na Dieta/metabolismo , Digestão , Ovinos/fisiologia , Animais , Hordeum/metabolismo , Lolium/metabolismo , Valor Nutritivo , Nylons , Poaceae/metabolismo , Análise de Regressão , Rúmen/metabolismo , Trifolium/metabolismo
16.
Rev. bras. oftalmol ; 76(6): 300-305, nov.-dez. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-899092

RESUMO

Abstract Objective: to compare nylon, fibrin glue and Vicryl® in the conjunctival autograft for treatment of primary pterygium. Methods: Prospective study approved by the Ethics Committee following the Declaration of Helsinki. 89 eyes were underwent pterygium excision and conjunctival autograft. They were grouped according to the technique: fibrin glue, nylon 10-0 and 8-0 Vicryl® and followed up for 3 months. Surgical Time, intra and postoperative symptoms, biomicroscopic signs, ocular discomfort ( by Visual Analogue Scale), aesthetic appearance and recurrences (day 21, 90 and 3 years) were evaluated. Results: The operative time was shorter with the fibrin glue (p<0.001). As to intraoperative symptomatology, burning sensation predominated with Vicryl® (p=0,012). The postoperative symptoms and signs: on day 1- secretion with fibrin glue (p=0.02), foreign body sensation (p=0.017) and subconjunctival hemorrhage (p=0.022) with Vycril®; on day 7- chemosis (p=0.035), hyperemia (p<0.001) and eyelid edema (p=0.011) with Vicryl®; on day 21-foreign body sensation (p=0.001) and conjunctival hyperemia (p<0.001) with nylon; on day 90- dry eye (p=0.005) with Vicryl®. Ocular discomfort was greater with Vycril® (p=0.015) on day 7. Final aesthetic appearance was superior with fibrin glue (p=0.003). The recurrences was greater on day 90: 20,7%(nylon), 10%(fibrin glue) and 19%(Vicryl®) (p=0.496) and after 3 years: 4.8% in NG, 0% in FGG, and 5.3% in VG (p=0.536). Conclusion: Fibrin glue showed efficacy, rapidity, less postoperative discomfort and better final aesthetic appearance. Vicryl® showed significant intraoperative and early postoperative symptoms and obvious signs of inflammation, beside ocular discomfort on day 7. Nylon caused more foreign body sensation and conjunctival hyperemia until its removal. The signs of recurrence were similar among the groups.


Resumo Objetivo: comparar o nylon, a cola de fibrina e o Vicryl® no autotransplante conjuntival para o tratamento do pterígio primário. Métodos: estudo prospectivo aprovado pelo Comitê de Ética seguindo a Declaração de Helsinque. 89 olhos foram submetidos à excisão de pterígio e autotransplante conjuntival, agrupados conforme as técnicas: nylon 10-0, cola de fibrina, e Vicryl® 8-0, acompanhados por 3 meses. Tempo cirúrgico, sintomas intra e pós-operatórios, sinais biomicroscópicos, desconforto ocular (Escala Analógica Visual), aspecto estético, recorrências no 21º e 90º dia pós-operatório e aos 3 anos. Resultados: O tempo operatório foi menor com a cola de fibrina e maior com Vicryl® (p<0,001). Sintomatologia intra-operatória: a ardência predominou com Vicryl® (p=0,012). Sintomas e sinais pós-operatórios significativos: no 1º dia, secreção com cola de fibrina (p=0,02), sensação de corpo estranho (p=0,017) e hemorragia subconjuntival (p=0,022) com Vycril®; No 7º dia - quemose (p=0,035), hiperemia (p<0,001) e edema da pálpebra (p=0,011) com Vicryl®; No 21º dia - sensação de corpo estranho (p=0,001) e hiperemia conjuntival (p<0,001) com nylon; No 90º dia - olho seco (p=0,005) com Vicryl®. Desconforto ocular: maior com Vycril® (p=0,015) no 7º dia. Aparência estética final: melhor com a cola (p=0,003). Sinais de recidiva: maior no 90º dia: 20,7%(nylon), 10%(cola) e 19%(Vicryl®) e após 3 anos: 4,8%(nylon), 0%(cola) e 5.3%(Vicryl®) (p=0,536). Conclusão: A cola de fibrina mostrou eficácia, rapidez, menor desconforto pós-operatório e melhor aspecto estético; o Vicryl®, maiores sintomas intraoperatórios, pós-operatórios iniciais e sinais evidentes de inflamação, aliados ao desconforto ocular no 7º dia; o nylon, mais sensação de corpo estranho e hiperemia conjuntival até sua remoção. Os sinais de recidiva foram semelhantes entre os grupos.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Poliglactina 910/uso terapêutico , Transplante Autólogo , Pterígio/cirurgia , Adesivo Tecidual de Fibrina/uso terapêutico , Túnica Conjuntiva/transplante , Nylons , Complicações Pós-Operatórias , Recidiva , Procedimentos Cirúrgicos Oftalmológicos/métodos , Adesivos Teciduais/uso terapêutico , Estudos Prospectivos , Seguimentos , Técnicas de Sutura , Resultado do Tratamento , Satisfação do Paciente , Período Perioperatório , Duração da Cirurgia , Autoenxertos , Escala Visual Analógica , Microscopia com Lâmpada de Fenda
17.
Rev. colomb. cienc. pecu ; 30(4): 267-277, oct.-dic. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-900625

RESUMO

Abstract Background: Ensiling spent mushroom substrate (SMS) generally increases its nutrient digestibility and quality. Objective: To determine the feed quality and digestibility of SMS from Pleurotus ostreatus (SMSP) inoculated with lactic acid bacteria (LAB: Lactobacillus brevis) in Hanwoo steers. Methods: Ruminal disappearance of SMSP and inoculated SMSP (ISMSP) were evaluated in three rumen-fistulated Hanwoo steers (408 ± 13.0 Kg body weight). Further, three healthy Hanwoo steers (336 ± 69.0 Kg body weight) were randomly allotted to one of three dietary treatments (control: 25% straw, 75% concentrates; treatments: 25% straw, 60% concentrates, and 15% of either SMSP or ISMSP) in a 3×3 Latin square design. Results: The chemical composition of the ISMSP diet did not differ from that of the control or the SMSP diets. In the ISMSP diet, the rate of decrease of pH of ruminal fluid and the increase in storage period was greater than with the SMSP diet. Ruminal disappearance of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber were slightly higher in steers fed ISMSP than those fed SMSP. Furthermore, the degradation rate and effective degradability of crude protein was greater in the ISMSP diet than in the SMSP diet. Effective ruminal fermentation characteristics and total nutrients digestibility were not affected by SMSP nor ISMSP diet. Conclusion: The SMSP and ISMSP diets could replace formulated concentrate without adverse effects and be a cost-effective feed for Hanwoo steers. Furthermore, LAB inoculation improved the SMSP preservation.


Resumen Antecedentes: El ensilado de cama de champiñón desechada (SMS) generalmente aumenta la digestibilidad y la calidad de sus nutrientes. Objetivo: Determinar la calidad del alimento y digestibilidad del SMS a partir de Pleurotus ostreatus (SMSP) inoculado con bacterias ácido-lácticas (LAB: Lactobacillus brevis) en bueyes Hanwoo. Métodos: La desaparición ruminal del SMSP y ISMSP (SMSP inoculado) fue evaluada en tres bueyes Hanwoo fistulados en el rumen (408 ± 13,0 Kg peso corporal). Igualmente, tres bueyes Hanwoo sanos (336 ± 69,0 Kg peso corporal) fueron asignados al azar a uno de los tres tratamientos dietéticos (control: 25% de heno, 75% de concentrados; tratamientos: 25% de heno, 60% de concentrados y 15% de SMSPo ISMSP) en un diseño cuadrado latino 3×3. Resultados: La composición química de la dieta ISMSP no difirió de la del control o de la dieta SMSP. En la dieta ISMSP, la tasa de disminución del pH del fluido ruminal y el incremento del tiempo de almacenamiento fueron mayores que los de la dieta SMSP. La desaparición ruminal de la materia seca, proteína cruda, fibra detergente neutra y la fibra detergente ácida fue ligeramente superior en los bueyes alimentados con el ISMSPque en aquellos alimentados con SMSP. Además, la tasa de degradación y la degradabilidad efectiva de la proteína cruda fueron mayores en la dieta ISMSPque en la dieta SMSP. Las características de la fermentación ruminal efectiva y la digestibilidad total de nutrientes no fueron afectadas por la dieta SMSP ni por la de ISMSP. Conclusión: Las dietas SMSPe ISMSP podrían reemplazar el concentrado formulado sin efectos adversos y ser una alimentación económica para los bueyes Hanwoo. Además, la inoculación con LAB mejoró la conservación del SMSP.


Resumo Antecedentes: Ensilagem de resíduo de substrato de cogumelo (SMS) geralmente aumenta a digestibilidade e a qualidade dos nutrientes. Objetivo: Determinar a qualidade da alimentação e digestibilidade do RSC apartir do Pleurotus ostreatus (SMSP) inoculado com bactérias de ácido láctico (LAB: Lactobacillus brevis) nos novilhos Hanwoo. Métodos: Desaparecimento ruminal do SMSP e ISMSP (SMSP inoculado) foram avaliados em três novilhos Hanwoo fistulados no rúmen (408 ± 13.0 Kg peso corporal). Além disso, três novilhos Hanwoo (336 ± 69.0 Kg peso corporal) foram aleatoriamente distribuídos para um dos três tratamentos dietéticos (controle: 25% palha, 75% concentrado; tratamentos: 25% palha, 60% concentrado, e 15% ambos SMSP e ISMSP) em um quadrado Latino de 3×3. Resultados: A composição química da dieta ISMSP não diferiu do controle ou das dietas SMSP. Na dieta ISMSP, a taxa de diminuição do pH do fluido ruminal e o aumento no período de armazenamento foram melhores do que com a dieta SMSP. O desaparecimento ruminal de matéria seca, proteína bruta, fibra em detergente neutro, e fibra detergente ácido foi ligeiramente superior em novilhos alimentados com ISMSP, do que aqueles alimentados com SMSP. Além disso, a taxa de degradação e degradabilidade da proteína bruta foi maior na dieta ISMSP, do que na dieta SMSP. As características efetivas de fermentação ruminal e a digestibilidade total de nutrientes não foram afetadas pela dieta SMSP, nem pela dieta ISMSP. Conclusão: Dietas com SMSP e ISMSP podem ser utilizados em substituição ao concentrado formulado sem causar efeitos adversos e ser um alimento rentável em novilhos Hanwoo. Além disso, a inoculação com LAB melhorou a qualidade conservante da SMSP.

18.
PróteseNews ; 4(3): 328-335, jul.-set. 2017. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-859234

RESUMO

O uso da resina acrílica na confecção de próteses, tanto totais quanto parciais removíveis, tem sido estudado durante anos com o intuito de caracterizar as propriedades intrínsecas do material nas mais diversas condições, como sua resistência mecânica, módulo elástico, dureza e propriedades biológicas quando modificadas por sais metálicos. Com a ocorrência constante de pacientes com necessidades protéticas especiais nas clínicas odontológicas, tais como os submetidos a ressecções oncológicas ou com defeitos orais congênitos, a confecção de próteses com o intuito de harmonizar as funções básicas tornou-se uma etapa cada vez mais desafiadora, com a necessidade de por vezes individualizar as peças, com a finalidade de selar ou preencher esses defeitos anatômicos. A resina acrílica não oferece uma resistência tão grande quando utilizada para extensões ou obturações palatinas associadas a uma armação de prótese parcial removível. No presente relato de caso clínico, buscou-se contornar essa deficiência com a instalação de uma rede de nylon na matriz resinosa previamente à acrilização, a fim de oferecer suporte e fortalecer a estrutura da armação, garantindo uma maior longevidade do conjunto. Deve-se ressaltar que o sucesso restaurador protético objetivou a devolução de função para o paciente e sua satisfação no uso da peça finalizada, de modo previsível e fundamentado na literatura atual.


The use of acrylic resin in the manufacture of both total and removable partial denture has been studied for years in order to characterize the intrinsic properties of the material under the most diverse conditions, such as mechanical strength, elastic modulus, hardness, as well as biological properties. With the constant occurrence of patients with special prosthetic needs in dental clinics, such as those submitted to oncologic resections or still patients with congenital oral defects, the preparation of prosthesis in order to harmonize the basic functions becomes an increasingly challenging stage, with the need to sometimes individualize the denture for the purpose of sealing or filling these anatomical defects. Acrylic resin alone does not offer such great resistance when used for extensions or palatine fillings associated with a removable partial denture frame. In the present case report, we overcame this defi ciency by installing a nylon net in the resin matrix prior to acrylization in order to support and strengthen the structure of the acrylic frame, guaranteeing its greater longevity. It should be emphasized that the restorative success of prosthetics aimed the return of function for the patient and their satisfaction in the use of the fi nished denture in a predictable way based on the current literature.


Assuntos
Humanos , Masculino , Idoso , Resinas Acrílicas , Prótese Dentária/métodos , Prótese Parcial Removível , Nylons , Neoplasias Orofaríngeas
19.
Braz. j. microbiol ; Braz. j. microbiol;48(2): 187-188, April.-June 2017.
Artigo em Inglês | LILACS | ID: biblio-839392

RESUMO

Abstract Pseudomonas taiwanensis strain SJ9 is a caprolactam degrader, isolated from industrial wastewater in South Korea and considered to have the potential for caprolactam bioremediation. The genome of this strain is approximately 6.2 Mb (G + C content, 61.75%) with 6,010 protein-coding sequences (CDS), of which 46% are assigned to recognized functional genes. This draft genome of strain SJ9 will provide insights into the genetic basis of its caprolactam-degradation ability.


Assuntos
Pseudomonas/genética , Pseudomonas/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/química , Caprolactama/metabolismo , Genoma Bacteriano , Análise de Sequência de DNA , Pseudomonas/isolamento & purificação , Composição de Bases , Microbiologia da Água , Biotransformação , Fases de Leitura Aberta , Anotação de Sequência Molecular , Resíduos Industriais , Coreia (Geográfico)
20.
Braz. J. Microbiol. ; 48(2): 187-188, abr.-jun. 2017.
Artigo em Inglês | VETINDEX | ID: vti-13222

RESUMO

Pseudomonas taiwanensis strain SJ9 is a caprolactam degrader, isolated from industrial wastewater in South Korea and considered to have the potential for caprolactam bioremediation. The genome of this strain is approximately 6.2 Mb (G + C content, 61.75%) with 6,010 protein-coding sequences (CDS), of which 46% are assigned to recognized functional genes. This draft genome of strain SJ9 will provide insights into the genetic basis of its caprolactam-degradation ability.(AU)


Assuntos
Pseudomonas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Biodegradação Ambiental , Nylons , República da Coreia , Caprolactama
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