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1.
J Appl Stat ; 50(10): 2194-2208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434632

RESUMO

In this paper, we propose a hierarchical Bayesian approach for modeling the evolution of the 7-day moving average for the number of deaths due to COVID-19 in a country, state or city. The proposed approach is based on a Gaussian process regression model. The main advantage of this model is that it assumes that a nonlinear function f used for modeling the observed data is an unknown random parameter in opposite to usual approaches that set up f as being a known mathematical function. This assumption allows the development of a Bayesian approach with a Gaussian process prior over f. In order to estimate the parameters of interest, we develop an MCMC algorithm based on the Metropolis-within-Gibbs sampling algorithm. We also present a procedure for making predictions. The proposed method is illustrated in a case study, in which, we model the 7-day moving average for the number of deaths recorded in the state of São Paulo, Brazil. Results obtained show that the proposed method is very effective in modeling and predicting the values of the 7-day moving average.

2.
J Endocrinol Invest ; 46(7): 1459-1464, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36645638

RESUMO

PURPOSE: Simultaneous pancreas-kidney transplantation (SPKT) remains the best treatment option in patients with type 1 diabetes and chronic kidney failure. There are only a few studies addressing the potential ischemic deterioration of peripheral arterial disease (PAD) due to blood diverting from the iliac artery to the kidney graft. We aimed to evaluate diabetic foot lesions and PAD evolution in SPKT recipients and investigate if they are more frequent in ipsilateral lower limb of kidney graft. METHODS: We developed a retrospective cohort, including patients submitted to SPKT in our tertiary center, between 2000 and 2017. Diabetic foot lesions and PAD frequencies were compared in the period before and after transplantation. RESULTS: Two hundred and eleven patients were included, 50.2% (n = 106) female, with a median age at transplantation of 35 years (IQR 9). After a median follow-up period of 10 years (IQR 7), patient, kidney, and pancreatic graft survival were 90.5% (n = 191), 83.4% (n = 176), and 74.9% (n = 158), respectively. Before transplant, 2.8% (n = 6) had PAD and 5.3% (n = 11) had history of foot lesions. In post-transplant period, 17.1% (n = 36) patients presented PAD and 25.6% (n = 54) developed diabetic foot ulcers, 47.6% (n = 35) of which in the ipsilateral and 53.3% (n = 40) in the contralateral lower limb of the kidney graft (p = 0.48). Nine patients (4.3%) underwent major lower limb amputation, 3 (30%) ipsilateral and 7 (70%) contralateral to the kidney graft (p = 0.29). CONCLUSIONS: Diabetic foot lesions were not more frequent in the ipsilateral lower limb of the kidney graft, therefore downgrading the 'steal syndrome' role in these patients.


Assuntos
Diabetes Mellitus Tipo 1 , Pé Diabético , Transplante de Rim , Doença Arterial Periférica , Humanos , Feminino , Criança , Pé Diabético/etiologia , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Doença Arterial Periférica/etiologia , Pâncreas , Resultado do Tratamento
3.
Comput Methods Biomech Biomed Engin ; 23(2): 54-68, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31813291

RESUMO

Osteoporosis is an osteometabolic disease, which promotes structural degradation of bone tissue and reduction of mineral density. We reported here a mechanical resistance assay from normal, osteopenic and osteoporotic trabecular vertebral bones of human cadavers. We performed a compressed test on ninety samples, evaluating Young's modulus and X-ray microtomography to measure bone volume fraction and trabecular thickness. This experimental data are employed for computing the orthotropic macroscopic behavior of vertebral trabecular bones using known analytical formulae that were obtained by Galka et al. (Arch Mech 51: 335-355, 1999) via an asymptotic homogenization model. A geometrical model with a periodic orthogonal plate-like structure is applied. The properties of the bone-trabecular mass are considered linear, homogeneous and orthotropic. Average values for all technical or engineering elastic properties are computed for three important regions of the trabecular bones corresponding to thirty individuals classified as normal, osteopenic or osteoporotic by calcaneus ultrassometry. This study could be useful for a better understanding of the elastic behavior of trabecular bones in human vertebral bodies, allowing an estimation of bone answer under stress in different directions and the risk of fracture associated with osteoporosis.HighlightsDescribing the elastic behavior of trabecular bones in human vertebral bodies at the micro and macroscopic.Allow a better estimation of the stress in different directions and risk of fracture associated with osteoporosis.Model request a very low computational cost.Offer a better understand the global effective coefficients of samples of trabecular bone, from the model of a periodic unit cell, in the format orthogonal plate-like structure with homogeneous bone mass.


Assuntos
Osso Esponjoso/fisiopatologia , Osteoporose/fisiopatologia , Coluna Vertebral/fisiopatologia , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Módulo de Elasticidade , Elasticidade , Humanos , Masculino , Osteoporose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Microtomografia por Raio-X
4.
Oper Dent ; 44(6): E271-E278, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31373891

RESUMO

OBJECTIVE: The aim of this study was to investigate the biofilm formation and cell viability of a polymer-infiltrated ceramic (PIC) and an yttria-stabilized polycrystalline zirconium dioxide ceramic (Y-TZP). The null hypothesis was that there would be no difference in biofilm formation and cell viability between the materials. METHODS AND MATERIALS: Streptococcus mutans biofilm was analyzed with scanning electron microscopy (SEM), confocal laser scanning microscopy, and colony counting (colony-forming units/mL). The cell viability (fibroblasts) of both materials was measured with 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium) (MTT) test. Roughness measurements were also performed. RESULTS: The PIC displayed higher roughness but showed similar colony-forming units and biovolume values to those of Y-TZP. SEM showed a higher amount of adhered fibroblasts on the PIC surface on the first day and similar amounts on both materials after seven days. Moreover, the materials were biocompatible with human fibroblasts. CONCLUSION: PIC and Y-TZP are biocompatible and present the same characteristics for biofilm formation; therefore, they are indicated for indirect restorations and implant abutments.


Assuntos
Polímeros , Streptococcus mutans , Biofilmes , Sobrevivência Celular , Cerâmica , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Ítrio , Zircônio
5.
Arq. bras. med. vet. zootec. (Online) ; 71(4): 1339-1347, jul.-ago. 2019. tab, graf, ilus
Artigo em Português | VETINDEX, LILACS | ID: biblio-1038623

RESUMO

O presente estudo objetivou comparar, biomecanicamente, por meio do ensaio de compressão excêntrica, a resistência dos implantes Clamp and Rod Internal Fixation (CRIF) 5,0mm e placa de reconstrução 3,5mm na fixação de fraturas distais de fêmur de cão. Foram utilizados 22 fêmures de 11 cadáveres de cão entre 2 e 7 anos de idade e peso corporal entre 20 e 40kg e subdivididos em dois grupos, denominados grupo CRIF (GC - 11 fêmures) e grupo placa (GP - 11 fêmures). Para realização dos testes, foi simulada falha que mimetizasse uma fratura distal nos corpos de prova, por meio de uma osteotomia de até 0,5cm, realizada com auxílio de serra oscilatória, imediatamente proximal ao início da tróclea. Os implantes foram fixados segundo os padrões AOSIF, lateralmente ao fêmur, sendo utilizados três parafusos distais e cinco proximais ao foco de fratura. Foi empregado o programa de computador PMI para calcular o ponto máximo de resistência antes da falha e avaliaram-se as variáveis força máxima, deformação máxima real, rigidez, força intermediária e deformação intermediária real. Não foram encontradas diferenças estatisticamente significativas entre os GC e GP quanto às variáveis avaliadas, sugerindo que ambos os implantes são boas opções de fixações para tais fraturas.(AU)


This study aims to compare the biomechanical properties, through compression eccentric test, of the resistance of the 5.0mm Clamp and Rod Internal Fixation Implants (CRIF) and 3.5mm reconstruction plate in fixing dog femur distal fracture. It was used 22 femurs from 11 dog cadavers with age between 2 and 7 years old and body weight between 20 and 40kg, subdivided into two groups, called CRIF Group (CG - 11 femurs) and plate group (PG - 11 femurs). A distal fracture in the specimens with a gap of 0.5cm osteotomy, was simulated to perform the test, performed by the oscillating saw, just proximal to the beginning of the trochlea. The implants were fixed by the standards AO / SIF, laterally to the femur, using three distal screws and five proximal to the fracture site. PMI computer program was used to calculate the maximum point of resistance before failure and evaluated the variables maximum strength, real maximum deformation, stiffness, intermediate strength and real intermediate deformation. No statistically significant differences were found between the GC and GP as the variables evaluated, suggesting that both implants are good fixation options for such fractures.(AU)


Assuntos
Animais , Cães , Placas Ósseas/veterinária , Fixadores Internos/veterinária , Fraturas do Fêmur/veterinária , Fixação de Fratura/métodos , Fixação de Fratura/veterinária
6.
Braz J Med Biol Res ; 52(4): e8154, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30970084

RESUMO

Elite judo demands high levels of physical and psychological skills. The brain-derived neurotrophic factor (BDNF) may be of particular interest in sports medicine for its ability to promote neuroplasticity. We investigated the plasma BDNF before and after a judo training session (Randori) and the maximal incremental ramp test (MIRT) in athletes from the Brazilian national judo team and compared the results between both exercise stimuli and sexes. Fifty-six elite judo athletes were recruited who performed each task on a separated day. Anthropometric, physiological, athletic parameters, and plasma BDNF levels were measured before and after the tasks (Randori and MIRT). The groups presented similar anthropometric and physiological characteristics at baseline for the two tasks. All athletes reached maximal performance for the tasks. Plasma levels of BDNF increased significantly after Randori and MIRT for all subjects, both men and women. When comparing both exercise stimuli, a greater increase in BDNF was observed after Randori. There was no significant difference in the delta BDNF between sexes. Our findings indicate that training specificity of sport gestures influenced the increase of blood BDNF levels.


Assuntos
Desempenho Atlético/fisiologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Artes Marciais/fisiologia , Resistência Física/fisiologia , Adulto , Feminino , Humanos , Masculino
7.
Braz. j. med. biol. res ; 52(4): e8154, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1001509

RESUMO

Elite judo demands high levels of physical and psychological skills. The brain-derived neurotrophic factor (BDNF) may be of particular interest in sports medicine for its ability to promote neuroplasticity. We investigated the plasma BDNF before and after a judo training session (Randori) and the maximal incremental ramp test (MIRT) in athletes from the Brazilian national judo team and compared the results between both exercise stimuli and sexes. Fifty-six elite judo athletes were recruited who performed each task on a separated day. Anthropometric, physiological, athletic parameters, and plasma BDNF levels were measured before and after the tasks (Randori and MIRT). The groups presented similar anthropometric and physiological characteristics at baseline for the two tasks. All athletes reached maximal performance for the tasks. Plasma levels of BDNF increased significantly after Randori and MIRT for all subjects, both men and women. When comparing both exercise stimuli, a greater increase in BDNF was observed after Randori. There was no significant difference in the delta BDNF between sexes. Our findings indicate that training specificity of sport gestures influenced the increase of blood BDNF levels.


Assuntos
Humanos , Masculino , Feminino , Adulto , Resistência Física/fisiologia , Artes Marciais/fisiologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Desempenho Atlético/fisiologia
8.
Arq. bras. med. vet. zootec. (Online) ; 69(4): 807-814, jul.-ago. 2017. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-876516

RESUMO

As lesões traumáticas dos membros que resultam em secções tendíneas são problemas comuns na clínica equina. Diversas complicações têm sido associadas à reparação dos tendões nessa espécie. O objetivo do presente trabalho foi avaliar biomecanicamente dois padrões de sutura e dois diferentes materiais aplicados às tenorrafias. Vinte e quatro peças de tendão flexor digital profundo de equinos foram seccionadas e suturadas em padrão locking loop duplo (grupo 1, com polipropileno; grupo 2, com poliglactina) ou em padrão locking loop simples associado à sutura de epitendão (grupo 3, com polipropileno; grupo 4, com poliglactina). Os corpos de prova foram submetidos a ensaios mecânicos de tração, em que se determinaram valores de força mínima, força máxima e pico de força, além do afastamento observado entre os cotos durante o pico máximo de força. Para avaliação dos resultados, foram utilizados os métodos ANOVA e os não paramétricos de Kruskal-Wallis e Mann-Whitney (P<0,05). Os maiores valores de força máxima foram documentados no grupo 3. Os valores de força mínima foram maiores nos grupos 3 e 4 que nos grupos 1 e 2, mas não diferiram significativamente entre os grupos 3 e 4. Os valores de pico de força foram maiores nos grupos 1 e 2 que no grupo 4, mas não diferiram significativamente no grupo 3. O afastamento foi maior nos grupos 1 e 2 quando comparados aos grupos 3 e 4. O padrão locking loop simples, com sutura de epitendão, atingiu maior resistência quando avaliado afastamento de até 3 milímetros entre os cotos tendíneos, sendo considerado padrão de escolha para aplicação clínica, tendo em vista os resultados obtidos neste trabalho.(AU)


Traumatic distal limb injuries resulting in tendon rupture are common in equine practice. Several complications have been associated with tendon repair in horses. The aim of this study was to compare the biomechanical properties of two tenorrhaphy techniques using two different suture materials. Twenty-four equine deep digital flexor tendon specimens were transected and sutured with the double locking loop pattern (polypropylene, group 1; polyglactin, group 2) or the single locking loop pattern with peripheral epitendon suture (polypropylene, group 3; polyglactin, group 4). Specimens were submitted to mechanical strain testing. Maximum, minimum and peak strain, and maximum, minimum and peak gap formation were evaluated. ANOVA and the non-parametric Kruskal-Wallis and Mann-Whitney tests were used (P<0.05). Higher maximum strength values were documented in group 3. Minimum strength values were higher in groups 3 and 4 than 1 and 2, but did not differ significantly between groups 3 and 4. Peak strength values were higher in groups 1 and 2 than 4, but did not differ significantly from group 3. Gap formation was greater in groups 1 and 2 than 3 and 4. The single locking loop pattern with epitendon suture performed with polypropylene had greater resilience, yielded lesser gap formation (3 mm) and is the pattern of choice for clinical application based on the results of this study.(AU)


Assuntos
Animais , Cavalos/cirurgia , Fenômenos Mecânicos , Técnicas de Sutura/veterinária , Suturas/veterinária , Tendões/cirurgia
9.
J Mech Behav Biomed Mater ; 71: 441-447, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28499606

RESUMO

PURPOSE: The purpose of the present study was to evaluate the distribution of stresses and consequent bone volume affected surrounding external hexagon or Morse taper dental implant systems by finite element analysis. MATERIAL AND METHODS: Two different dental implant-abutment designs were assessed: external hexagon or Morse taper joints. A mandibular bone model obtained from a computed tomography scan was used. The implant-abutment systems were axially or obliquely (45°) loaded on 150 N relatively to the central axis of the implant. The von Mises stresses were analysed in terms of magnitude and volume of affected surrounding bone. RESULTS: The von Mises equivalent values found on the cortical bone were higher than that recorded on the trabecular bone. Additionally, the bone volume associated with high stress values was higher in cortical and trabecular bone for oblique loading compared to axial loading. The values of von Mises equivalent stress around Morse taper implant-abutment system were lower on both axial and oblique loads than those recorded for external hexagon implant-abutment systems. CONCLUSIONS: Morse taper implant joints revealed a proper biomechanical behavior when compared to external hexagon systems concerning a significant volume of surrounding peri-implant bone subjected to lower stresses values.


Assuntos
Osso Esponjoso/fisiologia , Osso Cortical/fisiologia , Implantes Dentários , Análise do Estresse Dentário , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Mandíbula/fisiologia , Estresse Mecânico
10.
Environ Sci Pollut Res Int ; 24(14): 12529-12537, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27614638

RESUMO

Calcium titanate zirconate, Ca(Ti(1-x)Zrx)O3 (CZT), powders have been synthesised by the polymeric precursor method. The structural analysis of the CZT powders was monitored by X-ray diffraction (XRD), photoacoustic spectroscopy (PAS) and textural analysis. The photocatalytic properties were evaluated by methylene blue (MB) decomposition and real textile wastewater (RTW) combined treatment (coagulation/flocculation/photocatalysis). Chemical oxygen demand (COD) of RTW was successfully reduced from 6195 mg L-1 (untreated) to 662 mg L-1 after coagulation/flocculation with a tannin-based coagulant (Tanfloc®) and finally to 471 mg L-1 after combined treatment (coagulation/flocculation/photocatalysis) applying ultraviolet radiation and CaTiO3 as photocatalyst.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias/química , Compostos de Cálcio , Óxidos , Indústria Têxtil , Têxteis , Titânio , Raios Ultravioleta
11.
Oper Dent ; 41(6): 642-654, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27820691

RESUMO

This study evaluated the effects of excess cement removal techniques, with or without subsequent polishing, on biofilm formation and micromorphology in the marginal region of the tooth/restoration. From bovine teeth, 96 dentin blocks (4 × 8 × 2 mm) were produced, molded, and reproduced in type IV gypsum, on which 96 pressed ceramic blocks (Vita PM9, Vita Zahnfabrik; 4 × 8 × 2 mm) were produced via the lost wax technique. The dentin blocks and their respective ceramic blocks were cemented with a self-adhesive resin cement (RelyX U200, 3M ESPE), and cement excess was removed from the margin using four different techniques, followed or not by polishing with silicone rubber tips: MBr, removal with microbrush and photoactivation; MBr-Pol, MBr + polishing; Br, removal with brush and photoactivation; Br-Pol, Br + polishing; Photo-Expl, 5 seconds of initial photoactivation, removal with explorer, and final curing; Photo-Expl-Pol, Photo-Expl + polishing; Photo-SB, 5 seconds of initial photoactivation, removal with scalpel, and final curing; and Photo-SB-Pol, Photo-SB + polishing. After 24 hours, the roughness in the marginal region was analyzed using a profilometer (three measurements on each sample). Micromorphological analyses of the region were performed by stereomicroscope and scanning electron microscopy (SEM). Then the samples were contaminated with sucrose broth standardized suspension with Streptococcus mutans , Staphylococcus aureus , and Candida albicans and incubated for a period of 48 hours. The samples were quantitatively analyzed for bacterial adherence in the marginal region by confocal laser scanning microscopy and counting of colony-forming units (CFUs/mL) and qualitatively analyzed using SEM. Roughness data (Ra) were submitted to two-way analysis of variance, Tukey test at a confidence level of 95%, and Student t-tests. CFU, biomass, and biothickness data were analyzed by Kruskal-Wallis, Mann-Whitney, and Dunn tests. The removing technique statistically influenced Ra (MBr, p=0.0019; Br, p=0.002; Photo-Expl, p=0.0262; Photo-SB, p=0.0196) when comparing the polished and unpolished groups. The MBr and MBr-Pol technique differed significantly for CFU/mL values (p=0.010). There was no significant difference in the amounts of biomass and biothickness comparing polished and unpolished groups and when all groups were compared (p>0.05). Different morphological patterns were observed (more regular surface for polished groups). We conclude that margin polishing after cementation of feldspar/pressed ceramic restorations is decisive for achieving smoother surfaces, as the excess cement around the edges can increase the surface roughness in these areas, influencing bacterial adhesion.


Assuntos
Aderência Bacteriana , Polimento Dentário , Porcelana Dentária , Animais , Bovinos , Cerâmica , Teste de Materiais , Microscopia Eletrônica de Varredura , Cimentos de Resina , Staphylococcus aureus , Propriedades de Superfície
12.
Arq. bras. med. vet. zootec ; 68(4): 945-952, jul.-ago. 2016. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: lil-792462

RESUMO

Este é o primeiro estudo que compara o comportamento biomecânico de duas diferentes placas de avanço da tuberosidade tibial (ATT). Com o objetivo de minimizar a incidência de falhas de implante, foram realizados ensaios biomecânicos em 10 pares de membros pélvicos de cadáveres de cães. No membro pélvico direito, foi colocada placa de ATT fixa por garfo, e no membro pélvico esquerdo placa fixa por parafusos. Os ensaios foram realizados utilizando-se máquina universal de ensaios mecânicos Kratos(r), modelo KE3000, dotada de célula de carga de 3000N, com velocidade de ensaio de 20mm/min. O parâmetro força e os gráficos gerados foram gravados por meio de sistema de aquisição analógica TRACOMP-W95 (TRCV61285). A média da carga máxima até a falha foi de 128,70kg/F (mínimo 104,55kg/F e máximo 151,80kg/F) e de 141,99kg/F (mínimo 111,60kg/F e máximo 169,65kg/F) no grupo utilizando garfo e parafusos, respectivamente. O desvio-padrão dos grupos garfo e parafuso foi baixo, 12,99 e 17,21, respectivamente. Foi encontrada diferença significativa (P=0,03) entre as médias dos grupos. Com base nos resultados obtidos, conclui-se que existe diferença estatística significativa na resistência promovida entre as placas testadas, quando se observou que a placa fixa por parafusos promove maior resistência.(AU)


This is the first study to compare the biomechanical strength between the two different TTA plates. With the purpose of minimizing the incidence of implant failure, biomechanical tests were performed on 10 pairs of cadaveric hind limbs from dogs. The right hind limb of each dog was used as a model for the TTA plate fixed by fork, and the left pelvic limb was used as a model for the TTA plate fixed by screws. Tests were performed using a universal mechanical testing Kratos (r) machine, model KE 3000, equipped with a load cell of 3000N with a test speed of 20mm/min. The strength parameter and graphs generated were recorded via analog acquisition system TRACOMP-W95 (TRCV61285). The mean load to failure was 128.70kg/F (minimum 104.55kg and maximum 151.80kg/F) and 141.99kg/F (minimum 111.60kg/F and maximum 169.65kg/F) in the fork and screws groups respectively. The standard deviation of the fork and screws groups was low: 12.99 and 17.21 respectively. Significant difference (P= 0.03) between means of the groups was observed. From the results obtained it was concluded that there is a statistically significant difference in the resistance between plates and the plate fixed by screws promotes increased strength.(AU)


Assuntos
Animais , Cães , Fenômenos Biomecânicos , Implantação de Prótese/veterinária , Tíbia/transplante , Osteotomia/veterinária , Joelho de Quadrúpedes
13.
Arq. bras. med. vet. zootec ; 68(3): 673-682, tab
Artigo em Português | LILACS, VETINDEX | ID: lil-785712

RESUMO

O presente estudo comparou, por meio do ensaio de flexão em quatro pontos, a resistência de segmentos de rádios de cães autoclavados e desvitalizados em nitrogênio líquido. Avaliaram-se 40 rádios, que foram divididos em quatro grupos: grupo autoclave (GA), grupo controle autoclave (GCA), grupo nitrogênio (GN) e grupo controle nitrogênio (GCN). Os corpos de prova dos grupos GCA e GCN pertenciam ao lado contralateral dos grupos GA e GN, respectivamente. Os ossos foram autoclavados a 121°C, por 20min a 2atm. A desvitalização em nitrogênio foi realizada por meio da imersão em nitrogênio líquido, por 20min, seguida de descongelamento à temperatura ambiente, sendo finalizada por imersão em solução de NaCL a 0,9%, por mais 15min. Após os testes biomecânicos, foram comparadas as variáveis força máxima, rigidez, altura máxima à secção transversa do corpo de prova, deslocamento do baricentro em relação ao eixo x, flecha, tensão-tração, tensão-compressão e tensão máxima. Não foram encontradas diferenças estatisticamente significantes entre os grupos GN e GCN. Foram encontradas diferenças estatisticamente significantes entre os grupos GA e GCA somente na comparação da variável força máxima. A análise das variáveis tensão-tração, tensão-compressão e tensão máxima evidenciou diferenças estatisticamente significantes entre os grupos GA e GN, sendo os valores maiores para o grupo GA. Também foi realizada comparação entre os deltas (GN menos GCN e GA menos GCA), em que não foram observadas diferenças estatísticas.(AU)


The study compared through the four points bending test, the strength of bone segments autoclaved and devitalized in liquid nitrogen radius segments. 40 radius were used, collected and divided into 4 groups, as follows: Autoclave Group (GA), Control Autoclave Group (GCA), Nitrogen Group (NG) and Control Nitrogen Group (GCN). Bone segments from groups GCA and GCN were contralateral to GA and NG. The segments were autoclaved at 121ºC and 2 atm for 20 minutes. Nitrogen devitalization of the bone segments was obtained by 20 minutes immersion, followed by thawing at room temperature and 15 minutes immersion in 0.9% NaCL solution. After biomechanical tests the variables compared were maximum strength, stiffness, maximum hight trough the transverse section of the bone segment, centers of mass dislocation in relation to x axe, arrow, stress-tension, stress-compression and maximum stress. No statistically significant differences between the GN and GCN groups were found. Statistically significant differences were found between GA and GCA groups only in the comparison of the maximum force variable. The analysis of variable stress-tension, stress-compression and maximum stress showed statistically significant differences between the GA and GN groups, with higher values for the GA group. Comparison of the deltas (GN least GCN and GA least GCA) where no statistical differences were observed was also performed.(AU)


Assuntos
Animais , Cães , Fenômenos Biomecânicos , Densitometria/veterinária , Nitrogênio , Transplante Autólogo/veterinária , Ortopedia/veterinária , Osteossarcoma/veterinária , Esqueleto
14.
PLoS One ; 11(5): e0154325, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27152840

RESUMO

UNLABELLED: Breast cancer (BC) in young adult patients (YA) has a more aggressive biological behavior and is associated with a worse prognosis than BC arising in middle aged patients (MA). We proposed that differentially expressed miRNAs could regulate genes and proteins underlying aggressive phenotypes of breast tumors in YA patients when compared to those arising in MA patients. OBJECTIVE: Using integrated expression analyses of miRs, their mRNA and protein targets and stromal gene expression, we aimed to identify differentially expressed profiles between tumors from YA-BC and MA-BC. METHODOLOGY AND RESULTS: Samples of ER+ invasive ductal breast carcinomas, divided into two groups: YA-BC (35 years or less) or MA-BC (50-65 years) were evaluated. Screening for BRCA1/2 status according to the BOADICEA program indicated low risk of patients being carriers of these mutations. Aggressive characteristics were more evident in YA-BC versus MA-BC. Performing qPCR, we identified eight miRs differentially expressed (miR-9, 18b, 33b, 106a, 106b, 210, 518a-3p and miR-372) between YA-BC and MA-BC tumors with high confidence statement, which were associated with aggressive clinicopathological characteristics. The expression profiles by microarray identified 602 predicted target genes associated to proliferation, cell cycle and development biological functions. Performing RPPA, 24 target proteins differed between both groups and 21 were interconnected within a network protein-protein interactions associated with proliferation, development and metabolism pathways over represented in YA-BC. Combination of eight mRNA targets or the combination of eight target proteins defined indicators able to classify individual samples into YA-BC or MA-BC groups. Fibroblast-enriched stroma expression profile analysis resulted in 308 stromal genes differentially expressed between YA-BC and MA-BC. CONCLUSION: We defined a set of differentially expressed miRNAs, their mRNAs and protein targets and stromal genes that distinguish early onset from late onset ER positive breast cancers which may be involved with tumor aggressiveness of YA-BC.


Assuntos
Neoplasias da Mama/patologia , MicroRNAs/genética , Receptores de Estrogênio/metabolismo , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade
15.
J Biotechnol ; 216: 110-5, 2015 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-26481831

RESUMO

Insect cells are largely used for industrial production of vaccines, viral vectors and recombinant proteins as well as in research and development as an important tool for biology and bioprocess studies. They grow in suspension and are semi-adherent cells. Among the cell culture systems enabling scalable bioprocess the single-use fixed-bed iCELLis(®) bioreactors offer great advantages. We have established the conditions for Drosophila melanogaster Schneider 2 (S2) and Spodoptera frugiperda (Sf9) cells entrapment into the fixed-bed, cell growth and recover from the fixed-bed once high cell densities were attained. Our established protocol allowed these cells, at a cell seeding of 2×1E5 cells/microfiber carriers (MC) (3.5×1E6cells/mL; 1.7×1E4cells/cm(2)), to grow inside a 4m(2)/200mL fixed-bed attaining a concentration of 5.3×1E6 cells/MC (9.5×1E7cells/mL; 4.7×1E5 cells/cm(2)) for S2 cells or 4.6×1E6 cells/MC (8×1E7cells/mL; 4.1×1E5cells/cm(2)) for Sf9 cells. By washing the fixed-bed, entrapped cells could then be recovered from the fixed-bed at a high rate (>85%) with high viability (>95%) by increasing the agitation to 1200/1500rpm. Although the cell yields in the fixed-bed bioreactor were comparable to those obtained in a stirred tank (respectively, 1.3×1E10 and 2.5×1E10 total cells), S2 cells stably transfected with a cDNA coding for the rabies virus glycoprotein (RVGP) showed a 30% higher preserved rRVGP production (2.5±0.1 and 1.9±0.1µg/1E7 cells), as evidenced by a conformational ELISA evaluation. These findings demonstrate not only the possibility to entrap, cultivate to high densities and recover insect cells using a single-use fixed-bed bioreactor, but also that this system provides suitable physiological conditions for the entrapped cells to produce a cell membrane associated recombinant protein with higher specific biological activity as compared to classical suspension cell cultures.


Assuntos
Reatores Biológicos , Biotecnologia/métodos , Células Imobilizadas/citologia , Drosophila melanogaster/citologia , Proteínas Recombinantes/biossíntese , Spodoptera/citologia , Animais , Técnicas de Cultura de Células , Cinética
16.
Transpl Infect Dis ; 17(2): 308-13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25726707

RESUMO

BACKGROUND: The incidence of bloodstream infection (BSI) varies according to the transplanted organ. Mortality can be as high as 24%, with a significant impact on graft survival. Transplantation is a risk factor for multidrug-resistant (MDR) organisms, but comparison with a non-transplanted population in a single large cohort has not been described. METHODS: This is a prospective nationwide study (16 centers) reporting data on 2364 monomicrobial nosocomial BSIs, comparing 83 episodes in solid organ transplant patients with 2447 BSIs occurring in the general hospital population. RESULTS: The prevalence of groups of infecting organisms (gram-positive, gram-negative, and fungi) was similar between transplant patients and the general population and a similar crude mortality rate was observed (34.9% in transplant vs. 43.3% in non-transplant patients). Staphylococcus aureus was the single most frequently isolated organism in both groups, and Acinetobacter species was more frequently isolated in the general population. Regarding MDR organisms, Klebsiella species, and Enterobacter species resistant to cefepime, as well as Acinetobacter species resistant to meropenem, were significantly more frequent in transplant patients. CONCLUSION: Antimicrobial resistance is higher, particularly among gram-negative bacteria in the transplant population, although the overall mortality rate between transplant and non-transplant patients with nosocomial BSI is similar.


Assuntos
Bacteriemia/epidemiologia , Candidemia/epidemiologia , Infecção Hospitalar/epidemiologia , Transplantados/estatística & dados numéricos , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/microbiologia , Brasil/epidemiologia , Candidemia/microbiologia , Criança , Pré-Escolar , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Feminino , Fungemia/epidemiologia , Fungemia/microbiologia , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Adulto Jovem
17.
Orthop Traumatol Surg Res ; 100(7): 727-31, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25261174

RESUMO

BACKGROUND: Few biomechanical studies have assessed the resistance of the ligamentous structures of the sternoclavicular joint, and none have reproduced the physiological movements of the joint. Determining the structures that are injured in sternoclavicular dislocations is important for the surgical planning of acute or chronic ligament reconstruction. METHODS: Forty-eight joints from 24 human cadavers were studied, and they were divided into 4 groups of 12 joints each (retraction, protraction, depression and elevation). Biomechanical testing assessed primary and secondary failures. The mechanical resistance parameters between movements that occurred on the same plane (depression versus elevation, protraction versus retraction) were compared. RESULTS: The posterior sternoclavicular ligament was the most injured structure during the protraction test, but it was not injured during retraction. The anterior sternoclavicular ligament was the most affected structure during retraction and depression. The costoclavicular ligament was the most affected structure during elevation. Joint resistance was significantly greater during protraction movements when compared to retraction (P<0.05). CONCLUSION: The anterior sternoclavicular ligament was the most affected structure during retraction and depression movements. During protraction, lesions of the posterior sternoclavicular ligament were most frequent during elevation, and the costoclavicular ligament was the most frequently injured ligament. The resistance of the sternoclavicular joint was significantly greater during protraction movement when compared to retraction. LEVEL OF EVIDENCE: IV, basic science, biomechanics, cadaver model.


Assuntos
Luxações Articulares/cirurgia , Ligamentos Articulares/fisiopatologia , Procedimentos Ortopédicos , Procedimentos de Cirurgia Plástica/métodos , Amplitude de Movimento Articular/fisiologia , Articulação Esternoclavicular/fisiopatologia , Cadáver , Humanos , Luxações Articulares/fisiopatologia , Ligamentos Articulares/cirurgia , Articulação Esternoclavicular/cirurgia
18.
Curr Med Chem ; 21(15): 1707-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23992329

RESUMO

Infections caused by protozoan parasites are one of the most important public health problems in developing countries. One approach to design new drugs for these parasitic diseases relies on metabolic and molecular features which are ideally absent in mammalian hosts. Out of them, nutrient transporters play an important role since they were subjected to millions of years of adaptation to parasitism, in which this protozoan replaced many biosynthetic routes for transport systems. Here we address the current knowledge of trypanosomatids transport systems and the molecules related to such processes, including a description of permeases involved in drug uptake, and also those responsible of drug resistance. The latter process produces, in many cases, the treatment failure due to the loss of the transporter function, as is the case of eflornithine, as well as by increasing the extrusion of drugs, in which usually ABC-type transporters are involved. All these aspects and the perspectives on this topic are briefly updated in this review.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Protozoários/metabolismo , Tripanossomicidas/farmacologia , Trypanosoma/metabolismo , Animais , Transporte Biológico , Humanos , Tripanossomicidas/química , Trypanosoma/efeitos dos fármacos
19.
Cytotechnology ; 65(5): 829-38, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23340966

RESUMO

Recombinant rabies virus glycoprotein (RVGP) was expressed in cell membranes of stably transfected Drosophila S2 cells using constitutive and inducible promoters. Although with quantitative differences of RVGP expression in both systems, the cDNA transcription, as evaluated by relative RVGP mRNA levels measured by qRT-PCR, sustained the amount of RVGP producing cells and the RVGP volumetric (ΠRVGP) productivity. At the transition to the stationary cell growth phase, once the cell culture slowed down its rate of multiplication, an accumulation of RVGP mRNA and RVGP was clearly observed in both cell populations. Nevertheless, cell cultures performed under sub-optimal temperatures indicated that an envisaged increase in the RVGP production is not only dependent on cell growth rate, but essentially on optimal cell metabolic state.

20.
J Parasitol Res ; 2012: 743920, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22811885

RESUMO

Human infection by Schistosoma mansoni affects more than 100 million people worldwide, most often in populations of developing countries of Africa, Asia, and Latin America. The transmission of S. mansoni in human populations depends on the presence of some species of Biomphalaria that act as an intermediate host. The compatibility between S. mansoni and its intermediate host is influenced by behavioral, physiological, and genetical factors of the mollusc and the parasite. The susceptibility level of the mollusc has been attributed to the capacity of internal defense system (IDS)-hemocytes and soluble components of the hemolymph-to recognize and destroy the parasite, and this will be the center of interest of this paper. The schistosome-resistant Biomphalaria can be an alternative strategy for the control of schistosomiasis.

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