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1.
J Helminthol ; 98: e7, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38225903

RESUMO

Semperula wallacei (Issel, 1874) is a species of terrestrial slug that occurs in southeast China and the Pacific Basin and is the only species of its genus that occurs beyond the Oriental region and to the east of Wallace's line in the Australian region, where it has probably been introduced. In this study, we report for the first time S. wallacei as an intermediate host for Angiostrongylus cantonensis (Chen, 1935) based on histological and molecular analyses of slugs from Tuamasaga, Samoa, deposited at the Medical Malacological Collection (Fiocruz-CMM). DNA was obtained from the deparafinized tissues scraped from specimen slides. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) targeted to the internal transcribed spacer 2 (ITS2) region were carried out using the restriction enzyme Cla I. The RFLP profile observed for our larval specimen of S. wallacei was identical to the profile previously established for A. cantonensis, demonstrating that S. wallacei can be naturally infected with A. cantonensis and is likely to be an intermediate host for this parasitic nematode species in the field. The potential for geographical range expansion of S. wallacei in the Pacific Basin, its small size, and the general role of veronicellids as crop pests and hosts of nematodes, indicate the significance of S. wallacei as an invasive species in the Pacific Basin. Our work also highlights the importance of biological collections for investigating the environmental impact of invasive species on agriculture, public health, and biodiversity conservation.


Assuntos
Angiostrongylus cantonensis , Angiostrongylus , Gastrópodes , Nematoides , Infecções por Strongylida , Animais , Angiostrongylus cantonensis/genética , Austrália , Moluscos/parasitologia , Espécies Introduzidas , Infecções por Strongylida/veterinária , Infecções por Strongylida/parasitologia
2.
Pol J Vet Sci ; 26(2): 231-238, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389418

RESUMO

Studies on serum interleukin (IL)-31 levels in dogs with atopic dermatitis (AD) and their correlation with disease severity are limited. To the author's knowledge, there are no studies that measured serum IL-31 in dogs treated with lokivetmab injections, a selective inhibitor of this key cytokine in pruritus. The aim of the study was to evaluate serum IL-31 levels in dogs treated with lokivetmab and correlate it with the severity of canine atopic dermatitis using the pruritus visual analog scale (pVAS) and canine atopic dermatitis extent and severity index (CADESI-04). Ten client-owned dogs diagnosed with AD received two injections of lokivetmab four weeks apart. Disease severity was assessed using the pVAS and CADESI-04 scores before and after both injections. In addition, canine serum IL-31 levels were measured at the same moments. Serum IL-31 was detected in all dogs in the study. There was a significant reduction in pVAS scores and serum IL-31 after administrations. However, there was no difference in CADESI-04 scores, and there was no significant correlation between CADESI-04 scores and serum IL-31 in dogs diagnosed with AD. Nonetheless, a significant positive correlation was observed between the pVAS scores and serum IL-31 levels with lokivetmab therapy, which reinforces the role of IL-31 in the pathogenesis of pruritus in dogs with AD. The data presented here provide further evidence that IL-31 is directly involved in pruritus pathogenesis in dogs with AD. In addition, blocking IL-31 has a significant antipruritic effect, but has no influence on skin lesion severity and extension.


Assuntos
Dermatite Atópica , Doenças do Cão , Cães , Animais , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/veterinária , Prurido/tratamento farmacológico , Prurido/veterinária , Interleucinas , Resultado do Tratamento , Doenças do Cão/tratamento farmacológico
3.
J Am Chem Soc ; 145(5): 2930-2940, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36696237

RESUMO

Surface terminations and defects play a central role in determining how water interacts with metal oxides, thereby setting important properties of the interface that govern reactivity such as the type and distribution of hydroxyl groups. However, the interconnections between facets and defects remain poorly understood. This limits the usefulness of conventional notions such as that hydroxylation is controlled by metal cation exposure at the surface. Here, using hematite (α-Fe2O3) as a model system, we show how oxygen vacancies overwhelm surface cation-dependent hydroxylation behavior. Synchrotron-based ambient-pressure X-ray photoelectron spectroscopy was used to monitor the adsorption of molecular water and its dissociation to form hydroxyl groups in situ on (001), (012), or (104) facet-engineered hematite nanoparticles. Supported by density functional theory calculations of the respective surface energies and oxygen vacancy formation energies, the findings show how oxygen vacancies are more prone to form on higher energy facets and induce surface hydroxylation at extremely low relative humidity values of 5 × 10-5%. When these vacancies are eliminated, the extent of surface hydroxylation across the facets is as expected from the areal density of exposed iron cations at the surface. These findings help answer fundamental questions about the nature of reducible metal oxide-water interfaces in natural and technological settings and lay the groundwork for rational design of improved oxide-based catalysts.

4.
J Mech Behav Biomed Mater ; 138: 105583, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36442369

RESUMO

A home-made 3D Multi-Material Laser Powder Bed Fusion (3DMMLPBF) technology was exploited to manufacture novel multi-material Ti6Al4V-CoCrMo parts. This multi-material concept aims to bring to life a new and disruptive material's design concept for the acetabular cup. Only using a layer-by-layer approach it is possible to manufacture an acetabular cup capable to combine CoCrMo alloy wear resistance and Ti6Al4V alloy bone-friendly nature, in a single component, fabricated at once. This system works with multiple powder deposition functions and vacuum cleaning procedures allowing to use two different powders (Ti6Al4V and CoCrMo) in each layer and thus, allowing to construct 3D Multi-Material transition between distinct materials, point-by-point and layer-by-layer. In this sense, the manufacturing strategies and the functional transition between Ti6Al4V and CoCrMo with a mechanical interlocking were analyzed and discussed both from mechanical and metallurgical point of view. A small diffusion area and no evidence of defects or cracks can be found in the transition's regions between the distinct materials which are strong evidences of a solid metallurgical bonding at the interfacial regions of Ti6Al4V and CoCrMo materials. A functional transition is also obtained through a design capable to provide a 3D mechanical interlocking with potential of assuring, simultaneously, tensile and compressive strength. This proof of concept might be a step-ahead in Laser Powder Bed Fusion in which the most desired intrinsic of individual materials can be combined in a single component targeting biomedical disruptive solutions.


Assuntos
Ligas , Lasers , Teste de Materiais , Pós
5.
Osteoarthritis Cartilage ; 31(3): 317-339, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36481451

RESUMO

OBJECTIVE: To investigate the effects and mechanotransduction pathways of therapeutic ultrasound on chondrocytes. METHOD: PubMed, EMBASE and Web of Science databases were searched up to 19th September 2021 to identify in vitro studies exploring ultrasound to stimulate chondrocytes for osteoarthritis (OA) treatment. Study characteristics, ultrasound parameters, in vitro setup, and mechanotransduction pathways were collected. Risk of bias was judged using the Risk of Bias Assessment for Non-randomized Studies (RoBANS) tool. RESULTS: Thirty-one studies were included comprising healthy and OA chondrocytes and explants. Most studies had high risk of performance, detection and pseudoreplication bias due to lack of temperature control, setup calibration, inadequate semi-quantitatively analyzes and independent experiments. Ultrasound was applied to the culture plate via acoustic gel, water bath or culture media. Regardless of the setup used, ultrasound stimulated the cartilage production and suppressed its degradation, although the effect size was nonsignificant. Ultrasound inhibited p38, c-Jun N-terminal kinases (JNK) and factor nuclear kappa B (NFκB) pathways in OA chondrocytes to reduce apoptosis, inflammation and matrix degradation, while triggered phosphoinositide-3-kinase/akt (PI3K/Akt), extracellular signal-regulated kinase (ERK), p38 and JNK pathways in healthy chondrocytes to promote matrix synthesis. CONCLUSION: The included studies suggest that ultrasound application induces therapeutic effects on chondrocytes. However, these results should be interpreted with caution because high risk of performance, detection and pseudoreplication bias were identified. Future studies should explore the application of ultrasound on human OA chondrocytes cultures to potentiate the applicability of ultrasound towards cartilage regeneration of knee with OA.


Assuntos
Cartilagem Articular , Osteoartrite , Terapia por Ultrassom , Humanos , Condrócitos/metabolismo , Mecanotransdução Celular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Cartilagem Articular/metabolismo , Osteoartrite/metabolismo
6.
J Mech Behav Biomed Mater ; 136: 105508, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36265278

RESUMO

The development of implant metal-free surfaces has gained attention since non-benefic results have been reported related to the metallic ions released from metal implants to the human body. Ceramic coatings have been proposed as a possible solution however, the detachment of these coatings, during implantation or even in function, can compromise its function. In order to overcome this problem, this work proposes a novel hybrid Ti6Al4V-ZrO2 surface, starting with laser texturing of the Ti6Al4V substrate by Laser Nd:YV04, followed by the allocation of the zirconia (ZrO2) powder and its subsequent sintering by hot pressing process. Results revealed that zirconia strongly adheres to titanium textured surfaces since no detachment was found under tribological and adhesion scratch tests. Moreover, the tribological results showed that the incorporation of zirconia into textured titanium surface reduces significantly the wear rate of titanium (≈93%), which is a good indicator of low metallic particles/ions released to the body. These results suggest that this novel surface with good aesthetic properties and improved wear resistance (given by zirconia) and mechanical resistance (from titanium) can be a promising solution for dental implants, especially for implant/abutment or abutment/ceramic contact zones, and thus have a huge impact on the long-term performance of implants.


Assuntos
Implantes Dentários , Titânio , Humanos , Teste de Materiais , Titânio/química , Zircônio/química , Lasers , Íons , Propriedades de Superfície
7.
J Am Chem Soc ; 144(32): 14809-14818, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35926171

RESUMO

Electrocatalysis is a promising approach to convert waste nitrate to ammonia and help close the nitrogen cycle. This renewably powered ammonia production process sources hydrogen from water (as opposed to methane in the thermal Haber-Bosch process) but requires a delicate balance between a catalyst's activity for the hydrogen evolution reaction (HER) and the nitrate reduction reaction (NO3RR), influencing the Faradaic efficiency (FE) and selectivity to ammonia/ammonium over other nitrogen-containing products. We measure ammonium FEs ranging from 3.6 ± 6.6% (on Ag) to 93.7 ± 0.9% (on Co) across a range of transition metals (TMs; Ti, Fe, Co, Ni, Ni0.68Cu0.32, Cu, and Ag) in buffered neutral media. To better understand these competing reaction kinetics, we develop a microkinetic model that captures the voltage-dependent nitrate rate order and illustrates its origin as competitive adsorption between nitrate and hydrogen adatoms (H*). NO3RR FE can be described via competition for electrons with the HER, decreasing sharply for TMs with a high work function and a correspondingly high HER activity (e.g., Ni). Ammonium selectivity nominally increases as the TM d-band center energy (Ed) approaches and overcomes the Fermi level (EF), but is exceptionally high for Co compared to materials with similar Ed. Density functional theory (DFT) calculations indicate Co maximizes ammonium selectivity via (1) strong nitrite binding enabling subsequent reduction and (2) promotion of nitric oxide dissociation, leading to selective reduction of the nitrogen adatom (N*) to ammonium.

8.
Virus Res ; 313: 198746, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35292290

RESUMO

Canine parvovirus 2 (CPV-2), a highly contagious virus, affects dogs worldwide. Infected animals present severe and acute gastroenteritis which may culminate in death. CPV-2 VP2 protein is responsible for important biological functions related to virus-host interactions. Herein we obtained VP2 full-length gene sequences from Brazilian dogs with bloody diarrhea (n=15) and vaccine strains (n=7) produced by seven different laboratories and marketed in Brazil. All wild sequences and one vaccine strain were classified as CPV-2b and six vaccines were the classic CVP-2. Mutations in VP2 protein from vaccine and wild strains obtained in Brazil and worldwide were analyzed (n=906). Amino acid sequences from vaccine strains remarkably diverge from each other, even that classic CPV-2. Phylogenetic analysis based on VP2 gene and conducted with sequences displaying mutations in epitope regions previously described shows that vaccine strains are distantly related from the wide range of wild CPV-2. The impact of amino acid mutations over VP2 protein structure shows that vaccine and wild strains obtained in this study diverge in loop 3, an epitope region that plays a role in the CPV-2 host range. This is the first analysis of CPV-2 VP2 from commercial vaccine strains in Brazil and wild ones from Minas Gerais State, Brazil, and the first detailed attempt to vaccinal VP2 molecular and structural analyses.


Assuntos
Doenças do Cão , Infecções por Parvoviridae , Parvovirus Canino , Vacinas , Animais , Brasil , Cães , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Filogenia
9.
Infect Prev Pract ; 3(3): 100167, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34471868

RESUMO

Healthcare-associated infections (HAIs) are among the most common adverse events in hospitals. We used artificial intelligence (AI) algorithms for infection surveillance in a cohort study. The model correctly detected 67 out of 73 patients with HAIs. The final model used a multilayer perceptron neural network achieving an area under receiver operating curve (AUROC) of 90.27%; specificity of 78.86%; sensitivity of 88.57%. Respiratory infections had the best results (AUROC ≥93.47%). The AI algorithm could identify most HAIs. AI is a feasible method for HAI surveillance, has the potential to save time, promote accurate hospital-wide surveillance, and improve infection prevention performance.

10.
iScience ; 23(12): 101814, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33305178

RESUMO

In this perspective, we highlight the role of surface heterogeneity in electrosynthesis reactions. Heterogeneities may come in the form of distinct crystallographic facets, boundaries between facets or grains, or point defects. We approach this topic from a foundation of surface science, where signatures from model systems provide understanding of observations on more complex and higher-surface-area materials. In parallel, probe-based techniques can inform directly on spatial variation across electrode surfaces. We call attention to the role spectroscopy can play in understanding the impact of these heterogeneities in electrocatalyst activity and selectivity, particularly where these surface features have effects extending into the electrolyte double layer.

11.
J Mech Behav Biomed Mater ; 112: 104049, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32942227

RESUMO

OBJECTIVES: The aim of this study was to develop a novel design for implants surface functionalization through the production of HAp-coated zirconia structured surfaces by means of hybrid laser technique. The HAp-rich structured surfaces were designed to avoid hydroxyapatite (HAp) coating detachment from the zirconia surface during implant insertion, thus guaranteeing an effective osseointegration. MATERIALS AND METHODS: The functionalization process of zirconia surface started by creating micro-textures using a Nd:YAG laser and subsequent deposition of a HAp coating on the designated locations by dip-coating process. Afterwards, a CO2 laser was used to sinter the HAp coating. The potential of the HAp-coated zirconia structured surfaces was inspected concerning HAp bioactivity preservation, surface wettability, HAp coating adhesion to the textured surfaces and mechanical resistance of zirconia, as assessed by different approaches. RESULTS: The functionalized surfaces exhibited a superhydrophilic behavior (2.30 ± 0.81°) and the remaining results showed that through the hybrid strategy, it is possible to maintain the HAp bioactivity as well as promote a strong adhesion of HAp coating to the textured surfaces even after high energy ultrasonic cavitation tests and friction tests against bovine bone. It was also verified that the flexural strength of zirconia (503 ± 24 MPa) fulfills the strict requirements of the ISO 13356:2008 standard and as such is expectable to be enough for biomedical applications. SIGNIFICANCE: The promising results of this study indicate that the proposed surface design can open the window for manufacturing zirconia-based implants with improved bioactivity required for an effective osseointegration as it avoids the coating detachment problem during the implant insertion.


Assuntos
Durapatita , Zircônio , Animais , Bovinos , Materiais Revestidos Biocompatíveis , Lasers , Propriedades de Superfície , Titânio
12.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1213-1220, July-Aug. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131481

RESUMO

Surgical site infections (SSIs) and antimicrobial resistance among pathogens causing SSI are a growing concern in veterinary hospitals. One major reason, the widespread use of antimicrobials, has led to increased incidence of SSIs. This study identified bacteria and resistance profiles to antimicrobials in the SSI cases diagnosed at the Surgical Clinic of Small Animals in the Veterinary Hospital, Federal University of Viçosa, Brazil. The main genus identified was Staphylococcus, followed by Escherichia, Enterococcus, Bacillus, Shigella, Citrobacter, Proteus, Morganella, Serratia, Enterobacter, Pseudomonas and Klebsiella were also found, but in small number. The results indicated the predominance of Gram-negative bacteria among the collected samples. Most of isolates identified were resistant to more than one of the following antimicrobials: ampicillin, tetracycline, enrofloxacin, amoxicillin/clavulanic acid and cephalotin. Of the 17 Staphylococcus sp. isolates, two (11.8%) were methicillin-resistant Staphylococcus aureus (MRSA) and 11 (64.7%) of them were methicillin-resistant Staphylococcus pseudintermedius (MRSP). There were bacterial genera identified with resistance to all tested antimicrobials in different proportions. This should alert veterinary hospitals to the emergence of multidrug-resistant bacteria and to the requirement for the revision of surgical protocols with regard to antimicrobial prophylaxis and therapy.(AU)


As infecções em sítio cirúrgico (ISCs) e a resistência bacteriana entre os patógenos relacionados constituem uma preocupação crescente nos hospitais veterinários. O aumento na incidência de ISCs possui forte relação com o uso amplo e disseminado de antibióticos. O presente estudo identificou bactérias e perfis de resistência a antibióticos nos casos de ISCs diagnosticados na Clínica Cirúrgica de Pequenos Animais do Hospital Veterinário da Universidade Federal de Viçosa, Brasil. O principal gênero identificado foi Staphylococcus, seguido pelos gêneros Escherichia, Enterococcus, Bacillus, Shigella, Citrobacter, Proteus, Morganella, Serratia, Enterobacter, Pseudomonas e Klebsiella, porém, em menor quantidade. Os resultados demonstraram a predominância de bactérias Gram-negativas entre as amostras coletadas. A maioria dos isolados identificados eram resistentes a um ou a mais de um dos seguintes antibióticos: ampicilina, tetraciclina, enrofloxacina, amoxicilina/ácido clavulânico e cefalotina. Entre os 17 isolados de Staphylococcus sp., dois (11,8%) eram Staphylococcus aureus resistentes à meticilina (SARM) e 11 (64,7%) eram Staphylococcus pseudintermedius resistentes à meticilina (SPRM). Houve identificação de gêneros bacterianos com diferentes proporções de resistência para todos os antibióticos avaliados. Esses achados devem alertar os hospitais veterinários para a emergência de bactérias multirresistentes e para a necessidade de revisar a profilaxia e a terapia antimicrobiana referente aos protocolos cirúrgicos.(AU)


Assuntos
Animais , Gatos , Cães , Resistência Microbiana a Medicamentos , Infecção Hospitalar/veterinária , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana/veterinária
13.
Mater Sci Eng C Mater Biol Appl ; 109: 110492, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228989

RESUMO

Laser texturing is a technique that has been increasingly explored for the surface modification of several materials on different applications. Laser texturing can be combined with conventional coating techniques to functionalize surfaces with bioactive properties, stimulating cell differentiation and adhesion. This study focuses on the cell adhesion of laser-sintered coatings of hydroxyapatite (HAp) and 45S5 bioactive glass (45S5 BG) on zirconia textured surfaces using MC3T3-E1 cells. For this purpose, zirconia surfaces were micro-textured via laser and then coated with HAp and 45S5 BG glass via dip coating. Afterwards, the bioactive coatings were laser sintered, and a reference group of samples was conventionally sintering. The cell adhesion characterisation was achieved by cell viability performing live/dead analysis using fluorescence stains and by SEM observations for a qualitative analysis of cell adhesion. The in vitro results showed that a squared textured pattern with 100µm width grooves functionalized with a bioactive coating presented an increase of 90% of cell viability compared to flat surfaces after 48h of incubation. The functionalized laser sintered coatings do not present significant differences in cell viability when compared to conventionally sintered coatings. Therefore, the results reveal that laser sintering of HAp and 45S5 BG coatings is a fast and attractive coating technique.


Assuntos
Osteoblastos/efeitos dos fármacos , Zircônio/química , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Durapatita/química , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley
14.
Mater Sci Eng C Mater Biol Appl ; 108: 110390, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923937

RESUMO

The development of new surface designs to enhance the integration process between surgically placed implants and biological tissues remains a challenge for the scientific community. In this way and trying to overcome this issue, in this work, laser technology was explored to produce novel textures on the surface of green zirconia compacts produced by cold pressing technique. Two strategies regarding line design (8 and 16 lines design) and different laser parameters (laser power and number of laser passages) were explored to assess their influence on geometry and depth of created textures. The produced textures were evaluated with Scanning Electron Microscopy (SEM) and it was observed that well-defined textured surfaces with regular geometric features (cavities or pillars) were obtained by laser combining different strategies lines design and parameters. The potential of proposed textures was also evaluated regarding surface wettability, friction performance (static and dynamic coefficient of friction evolution) against bone, aging resistance and flexural strength. Results demonstrated that all the produced textures display a super hydrophilic or hydrophilic behavior. Regarding the friction behavior, it was experimentally observed a high initial static coefficient of friction (COF) for all produced textures. Concerning the aging resistance, all the textured surfaces revealed a low monoclinic content, less than 25% after 5 h of hydrothermal aging. The flexural strength results showed that the mechanical resistance of zirconia was not significantly compromised with the laser action. Based on the obtained results, it is possible to prove that the processing route used for manufacturing the new and different surface designs (cold pressing technique followed by laser texturing) showed to be particularly effective for the production of zirconia implants with customized surface designs according to the properties required in a specific application. These new surface designs besides to enhance the surface wettability and also to improve the fixation at the initial moment of the implantation, do not significantly compromise the resistance to aging and the mechanical performance of zirconia. Hence, a positive impact on the long-term performance of the zirconia implants may be expected with the proposed novel laser textured surface designs.


Assuntos
Lasers , Próteses e Implantes , Zircônio/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Temperatura
15.
Braz J Med Biol Res ; 52(12): e9124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826182

RESUMO

Carbohydrate antigen 125 (CA125) has long been used as an ovarian cancer biomarker. However, because it is not specific for ovarian cells, CA125 could also be used to monitor congestion and inflammation in heart disease. Acute heart failure (HF) is used to identify patients with a worse prognosis in ST-segment elevation myocardial infarction (STEMI). We aimed to determine the association of CA125 with acute HF in STEMI and to compare CA125 with N-terminal pro brain natriuretic peptide (NTproBNP) with a cross-sectional study. At admission, patients were examined to define Killip class and then underwent coronary angioplasty. Blood samples, preferably taken in the hemodynamic ward, were centrifuged (1500 g for 15 min at ambient temperature) and stored at -80°C until biomarker assays were performed. Patients were divided into two groups according to the presence or absence of congestion. Patients in Killip class ≥II were in the congestion group and those with Killip

Assuntos
Antígeno Ca-125/sangue , Edema Pulmonar/etiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Idoso , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Edema Pulmonar/sangue , Edema Pulmonar/diagnóstico , Curva ROC , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue
16.
Mater Sci Eng C Mater Biol Appl ; 104: 109901, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500026

RESUMO

The development of smart biomedical implants with intrinsic communication system between sensors and actuators, or between implant and patient, remains a challenge for scientific community. Titanium and its alloys, especially Ti6Al4V, are the most used materials in the implant's fabrication. The present work is concerned with implant internal communication printing process and presents a detailed study on titanium alloy (Ti6Al4V) surface texturing and their characterization (morphological and chemical) produced by a Nd: YAG laser, aiming to create localized electrical insulation zones, necessary to accommodate electrical communication systems. The characterization of the textured surface was carried out by scanning electron microscopy and the heat affected zone was analyzed by X-ray diffraction. The results showed the formation of α-Ti, Ti6O and Ti2O phases on the textured surface. Through simulations in TINA software, the outer oxide layer formed during laser texturing had efficiency above 90% as insulator when an electrical current was applied.


Assuntos
Eletricidade , Lasers , Óxidos/química , Titânio/química , Ligas , Oxirredução , Propriedades de Superfície , Difração de Raios X
17.
J Mech Behav Biomed Mater ; 94: 110-125, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30884280

RESUMO

Zirconia implants are becoming a preference choice for different applications such as knee, dental, among others. In order to improve osseointegration, implant's surfaces are usually coated with bioactive materials like hydroxyapatite (HAp) and beta-tricalcium phosphate (ß-TCP) that are very similar to the calcium phosphates found in bones. However, due to the implantation process, these coatings can be detached from the zirconia surface, leading to implant premature failure. In this work, a new component materials design aiming to avoid this coating detachment problem is proposed. It is based on the use of a bioactive zirconia-calcium phosphate composite outer layer onto the zirconia bulk, where the zirconia bulk provides mechanical strength and the outer layer provides biological performance. In order to assess the potential of this new materials design, two types of bioactive zirconia outer composite layers (zirconia reinforced by 10 vol% of HAp and by 10 vol% of ß-TCP) were produced by press and sinter process and the gradated samples were fully characterized concerning materials, mechanical resistance, fatigue resistance, and biological performance, as measured by different approaches. Results showed that the novel component materials design and the manufacturing process proposed for producing the bioactive zirconia samples with outer composite layers on zirconia bulk substrates are a promising solution for implants, with improved biological performance without substantially compromising their overall mechanical and fatigue properties.


Assuntos
Próteses e Implantes , Zircônio/química , Fosfatos de Cálcio/química , Durapatita/química , Módulo de Elasticidade , Dureza , Propriedades de Superfície , Temperatura , Molhabilidade
18.
Braz. j. med. biol. res ; 52(12): e9124, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055465

RESUMO

Carbohydrate antigen 125 (CA125) has long been used as an ovarian cancer biomarker. However, because it is not specific for ovarian cells, CA125 could also be used to monitor congestion and inflammation in heart disease. Acute heart failure (HF) is used to identify patients with a worse prognosis in ST-segment elevation myocardial infarction (STEMI). We aimed to determine the association of CA125 with acute HF in STEMI and to compare CA125 with N-terminal pro brain natriuretic peptide (NTproBNP) with a cross-sectional study. At admission, patients were examined to define Killip class and then underwent coronary angioplasty. Blood samples, preferably taken in the hemodynamic ward, were centrifuged (1500 g for 15 min at ambient temperature) and stored at −80°C until biomarker assays were performed. Patients were divided into two groups according to the presence or absence of congestion. Patients in Killip class ≥II were in the congestion group and those with Killip <II in the absence of congestion group. We evaluated 231 patients. The mean age was 63.3 years. HF at admission was identified in 17.7% of patients. CA125 and NTproBNP levels were higher in patients with Killip class ≥II than those with Killip class <II (8.03 vs 9.17, P=0.016 and 772.45 vs 1925, P=0.007, respectively). The area under the receiver operator characteristic curve was 0.60 (95%CI 0.53−0.66, P=0.024) for CA125 and 0.63 (95%CI 0.56−0.69, P=0.001) for NTproBNP. There was no statistical difference between the curves (P=0.69). CA125 has similar use to NTproBNP in identifying acute HF in patients presenting with STEMI.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Edema Pulmonar/etiologia , Antígeno Ca-125/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Edema Pulmonar/diagnóstico , Edema Pulmonar/sangue , Biomarcadores/sangue , Estudos Transversais , Valor Preditivo dos Testes , Fatores de Risco , Curva ROC , Infarto do Miocárdio com Supradesnível do Segmento ST
19.
J Biomed Mater Res B Appl Biomater ; 106(4): 1534-1545, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28748671

RESUMO

This work presents a novel texture design for implants surface functionalization, through the creation of line-shaped textures on Ti6Al4V surfaces and subsequent sintering of hydroxyapatite (HAp) powder into the designated locations. HAp-rich locations were designed to avoid HAp detachment during insertion, thus guaranteeing an effective osseointegration. This process starts by creating textured lines using a Nd:YAG laser, filling these lines with HAp powder and sintering HAp using a CO2 laser. The adhesion of HAp is known to be influenced by HAp sintering parameters, especially laser power and scanning speed and also by the textured lines manufacturing. Different laser parameters combinations were used to assess the sintering and adhesion of HAp to the textured lines. HAp adhesion was assessed by performing high energy ultrasonic cavitation tests and sliding tests mimicking an implant insertion, with Ti6Al4V/HAp specimens sliding against animal bone. The HAp content retained after these tests was measured and results showed that an excellent HAp sintering and adhesion was achieved when using a scan speed of 1 mm/s and laser power between 9 and 9.6 W. It is important to emphasize that results indicated that the HAp bioactivity was maintained when using these conditions, validating this functionalization process for the production of hip prosthesis with improved bioactivity. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1534-1545, 2018.


Assuntos
Materiais Revestidos Biocompatíveis/química , Durapatita/química , Titânio/química , Ligas , Lasers , Osseointegração , Propriedades de Superfície
20.
Parasitology ; 144(13): 1677-1685, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28805164

RESUMO

Fascioliasis is a condition caused by the trematode Fasciola hepatica. In this paper, the spatial distribution of F. hepatica in bovines in Brazil was modelled using a decision tree approach and a logistic regression, combined with a geographic information system (GIS) query. In the decision tree and the logistic model, isothermality had the strongest influence on disease prevalence. Also, the 50-year average precipitation in the warmest quarter of the year was included as a risk factor, having a negative influence on the parasite prevalence. The risk maps developed using both techniques, showed a predicted higher prevalence mainly in the South of Brazil. The prediction performance seemed to be high, but both techniques failed to reach a high accuracy in predicting the medium and high prevalence classes to the entire country. The GIS query map, based on the range of isothermality, minimum temperature of coldest month, precipitation of warmest quarter of the year, altitude and the average dailyland surface temperature, showed a possibility of presence of F. hepatica in a very large area. The risk maps produced using these methods can be used to focus activities of animal and public health programmes, even on non-evaluated F. hepatica areas.


Assuntos
Distribuição Animal , Doenças dos Bovinos/epidemiologia , Fasciola hepatica/fisiologia , Fasciolíase/epidemiologia , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/parasitologia , Clima , Árvores de Decisões , Fasciolíase/parasitologia , Sistemas de Informação Geográfica , Modelos Logísticos , Modelos Teóricos , Prevalência , Medição de Risco , Fatores de Risco , Análise Espacial
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