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1.
J Mech Behav Biomed Mater ; 131: 105246, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35512486

RESUMEN

In this study, Selective Laser Melting (SLM) was used to produce mono-material Ti64Al4V- and NiTi-cubic cellular structures with an open-cell size and wall thickness of 500 µm and 100 µm, respectively. Bioactive beta-tricalcium phosphate (ßTCP) and polymer poly-ether-ether ketone (PEEK) were used to fill the produced structures open-cells, thus creating multi-material components. These structures were characterized in vitro in terms of cell viability, adhesion, differentiation and mineralization. Also, bio-tribological experiments were performed against bovine plate to mimic the moment of implant insertion. Results revealed that metabolic activity and mineralization were improved on SLM mono-material groups, when compared to the control group. All cell metrics were improved with the addition of PEEK, conversely to ßTCP where no significant differences were found. These results suggest that the proposed solutions can be used to improve implants performance.


Asunto(s)
Aleaciones , Prótesis e Implantes , Animales , Bovinos , Éteres , Cetonas/química , Cetonas/farmacología , Ensayo de Materiales , Polietilenglicoles/química , Polímeros/farmacología , Titanio/química , Titanio/farmacología
2.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1422-1430, Nov.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355676

RESUMEN

This work was conducted to evaluate the effect of deferred pasture condition of Brachiaria brizantha cv. Marandu in the late winter on tillering during the growing season. The treatments were three pasture conditions at late winter: short pasture, tall pasture and tall/mown pasture. In September and October, tiller appearance rate (TApR) and tiller mortality rate (TMoR) were greater in the tall/mown pasture. In November and December, tall pasture presented greater TApR. From November to January the TMoR was greater in the tall pasture. The tiller stability index of short and tall/mown pastures were greater in October. The short pasture presented a greater tiller number than the tall and tall/mown pastures during the entire experimental period. Deferred and short pasture of marandu palisade grass at late winter presents in general lower tiller mortality and higher population density of tillers from the early spring onwards, in comparison to tall pasture. The mowing of marandu palisade grass with high forage mass at the late winter, although it only temporarily compromises the population stability of tillers, also stimulates its fast tillering from spring on.(AU)


Este trabalho foi conduzido com o objetivo de avaliar o efeito da condição da pastagem diferida de Brachiaria brizantha cv. Marandu ao final do inverno sobre o perfilhamento durante a estação de crescimento. Os tratamentos foram três condições de pastagem no final do inverno: pasto baixo, pasto alto e pasto alto/roçado. Nos meses de setembro e outubro, a taxa de aparecimento de perfilhos (TApP) e a taxa de mortalidade de perfilhos (TMoP) foram maiores na pastagem alta/roçada. Nos meses de novembro e dezembro, a pastagem alta apresentou maior TApP. De novembro a janeiro, a TMoP foi maior na pastagem alta. Os índices de estabilidade de perfilhos das pastagens baixas e altas/roçadas foram maiores em outubro. A pastagem baixa apresentou maior número de perfilhos do que as pastagens altas e altas/roçadas durante todo o período experimental. A pastagem diferida e baixa de capim-marandu no final do inverno apresenta, em geral, menor mortalidade de perfilhos e maior densidade populacional de perfilhos no início da primavera, em comparação com a pastagem alta. A roçada do capim-marandu com alta massa de forragem ao final do inverno, embora comprometa apenas temporariamente a estabilidade populacional dos perfilhos, também estimula o perfilhamento rápido a partir da primavera.(AU)


Asunto(s)
Estaciones del Año , Pastizales/análisis , Brachiaria/crecimiento & desarrollo
3.
Braz J Med Biol Res ; 54(11): e11556, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34550274

RESUMEN

Sedentary time is associated with increased obesity in police officers. Caffeine intake may reduce sedentary time but it has not been extensively investigated. In the present study, the effect of caffeine ingestion on sedentary time was investigated in obese police officers. Fourteen obese police officers ingested either 5 mg/kg of caffeine or cellulose (placebo) for six days. Information on inactivity time, time spent with physical activities, self-reported perception of tiredness, and physical activity disposition was obtained daily during the intervention period. Sedentary and physical activity times were divided into two intraday periods (T1: 08:00 am-02:00 pm and T2: 02:00 pm-08:00 pm). Caffeine intake decreased the sedentary time in both T1 (79.2±2.2%) and T2 (79.1±2.5%), when compared with T2 of the placebo condition (81.1±3.6%, P<0.05). Caffeine intake also increased the time spent on light physical activities in T1 and T2 (17±2 and 18±2%), when compared with T2 of the placebo condition (16±3%, P<0.05). In addition, sedentary time increased and light physical activity time decreased from T1 to T2 in the placebo (P<0.001) but not in the caffeine condition (P=0.81). Caffeine intake had no effect on tiredness (P>0.05), but it increased the self-reported physical activity disposition compared to the placebo condition (4.5±2.7 vs 3.2±2.3 units, P<0.05). Caffeine intake reduced the sedentary time and increased the time spent on light physical activities of obese police officers, which seems to be related to a higher disposition for the practice of physical activity.


Asunto(s)
Cafeína , Conducta Sedentaria , Ingestión de Alimentos , Ejercicio Físico , Humanos , Obesidad , Policia
4.
Braz. j. med. biol. res ; 54(11): e11556, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1339453

RESUMEN

Sedentary time is associated with increased obesity in police officers. Caffeine intake may reduce sedentary time but it has not been extensively investigated. In the present study, the effect of caffeine ingestion on sedentary time was investigated in obese police officers. Fourteen obese police officers ingested either 5 mg/kg of caffeine or cellulose (placebo) for six days. Information on inactivity time, time spent with physical activities, self-reported perception of tiredness, and physical activity disposition was obtained daily during the intervention period. Sedentary and physical activity times were divided into two intraday periods (T1: 08:00 am-02:00 pm and T2: 02:00 pm-08:00 pm). Caffeine intake decreased the sedentary time in both T1 (79.2±2.2%) and T2 (79.1±2.5%), when compared with T2 of the placebo condition (81.1±3.6%, P<0.05). Caffeine intake also increased the time spent on light physical activities in T1 and T2 (17±2 and 18±2%), when compared with T2 of the placebo condition (16±3%, P<0.05). In addition, sedentary time increased and light physical activity time decreased from T1 to T2 in the placebo (P<0.001) but not in the caffeine condition (P=0.81). Caffeine intake had no effect on tiredness (P>0.05), but it increased the self-reported physical activity disposition compared to the placebo condition (4.5±2.7 vs 3.2±2.3 units, P<0.05). Caffeine intake reduced the sedentary time and increased the time spent on light physical activities of obese police officers, which seems to be related to a higher disposition for the practice of physical activity.


Asunto(s)
Humanos , Cafeína , Conducta Sedentaria , Ejercicio Físico , Policia , Ingestión de Alimentos , Obesidad
5.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 40-48, Jan.-Feb. 2020. tab, ilus
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1088936

RESUMEN

A ultrassonografia é um exame complementar não invasivo ainda pouco utilizado na avaliação prepucial e sem descrições detalhadas da parte livre do pênis (PLP) de bovinos. Este estudo objetivou padronizar a ultrassonografia prepucial em bovinos hígidos da raça Nelore com um ano de idade e, para tanto, descreveu o aspecto da lâmina interna prepucial (LIP) e da PLP, determinando as principais janelas acústicas, a viabilidade da utilização de contraste no lúmen da cavidade prepucial (LCP) e o melhor posicionamento do animal para a realização do exame. O escaneamento foi realizado com os animais na posição quadrupedal e em decúbito lateral direito. Foram determinadas cinco janelas acústicas a partir do óstio até a identificação do recesso prepucial. Os escaneamentos foram realizados nos planos longitudinais, transversais e dorsais, antes e após a infiltração de solução fisiológica a 0,9% no LCP. Como conclusões, o exame ultrassonográfico permitiu identificar a LIP e a PLP em todos os planos e em todas as janelas acústicas propostas. O melhor ponto de referência é a identificação da glande. O posicionamento quadrupedal é mais adequado para a realização do exame e o uso de contraste é recomendado para delimitação topográfica das estruturas.(AU)


Ultrasonography is a noninvasive complementary exam that is still rarely used in the preputial evaluation and without detailed descriptions of the bovine free end of the penis. The purpose of this study was to standardize preputial ultrasonography in one-year-old healthy Nelore cattle, describing the main acoustic windows, the viability of using contrast in the preputial cavity and the best positioning of the animal for performing the ultrasound examination. The scanning was performed with the animals in standing and decubitus position. Five acoustic windows were determined from the preputial ostium to the preputial fornix, at the free end of the penis. The scans were performed in longitudinal, transverse and dorsal planes, before and after infiltration of 0.9% saline solution into the preputial cavity. As conclusions, the ultrasound examination is able to identify the internal layer and the free part of the penis in all proposed planes and acoustic windows. The best landmark is the identification of the glans. Furthermore, standing positioning is the most appropriate to perform the exam and the use of contrast is recommended for topographic delimitation of the structures.(AU)


Asunto(s)
Animales , Masculino , Bovinos , Pene/diagnóstico por imagen , Prepucio/diagnóstico por imagen , Ultrasonografía/métodos
6.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1750-1758, set.-out. 2019. tab, graf, ilus
Artículo en Portugués | VETINDEX, LILACS | ID: biblio-1038659

RESUMEN

The effects of housing lactating sows at different locations in a shed with evaporative cooling system (ECS) on their thermoregulation and reproductive and productive performance of the sow and the litter in summer were determined. 34 females were used in the three lines of cages at these locations: near the pad cooling; in the middle of the shed and near the exhaust fans. The air temperature and the temperature and humidity index (THI) were lower near the pad cooling (22.38ºC, 71.84) than the middle (24.56ºC, 74.82) and near the exhaust fans (25.00°C, 75.62). Respiratory rate, rectal and surface temperatures were lower in sows near the pad cooling (43.67 breaths.min -1 , 38.40°C; 29.51°C) than in the center (52.04 breaths.min -1 ; 38.48ºC; 32.02ºC) and near the exhaust fans (56.38 breaths.min-1, 38.93ºC; 32.52ºC). The backfat thickness, the weaning-estrus interval and daily average consumption of the sows, number of weaning piglets, corporal mass and daily average gain of the piglets were not influenced by the location of housing in the shed. Lactating sows housed in the middle and near the exhaust fans in the ECS presented increased thermoregulation physiological variables, however, this did not impair the performance.(AU)


Asunto(s)
Animales , Femenino , Embarazo , Porcinos/crecimiento & desarrollo , Temperatura , Regulación de la Temperatura Corporal/fisiología , Bienestar del Animal/organización & administración , Trastornos de Estrés por Calor/prevención & control , Vivienda para Animales/organización & administración
7.
Mater Sci Eng C Mater Biol Appl ; 98: 705-716, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30813075

RESUMEN

Load-bearing implants success is strongly dependent on several physical and chemical properties that are known to drive cellular response. In this work, multi-material ß-TCP-Ti6Al4V cellular structures were designed to combine Ti6Al4V mechanical properties and ß-Tricalcium Phosphate bioactivity, in order to promote bone ingrowth as the bioactive material is being absorbed and replaced by newly formed bone. In this sense, the produced structures were characterized regarding roughness, wettability, ß-TCP quantity and quality inside the structures after fabrication and the pH measured during cell culture (as consequence of ß-TCP dissolution) and those aspects were correlated with cellular viability, distribution, morphology and proliferation. These structures displayed a hydrophilic behavior and results showed that the addition of ß-TCP to these cellular structures led to an alkalization of the medium, aspect that significantly influences the cellular response. Higher impregnation ratios were found more adequate for lowering the media pH and toxicity, and thus enhance cell adhesion and proliferation.


Asunto(s)
Materiales Biocompatibles/química , Fosfatos de Calcio/química , Aleaciones , Animales , Línea Celular , Ensayo de Materiales , Ratas , Titanio/química
8.
Eur J Nucl Med Mol Imaging ; 45(6): 1031-1040, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29478081

RESUMEN

PURPOSE: PET using radiolabelled amino acids has become a promising tool in the diagnostics of gliomas and brain metastasis. Current research is focused on the evaluation of amide proton transfer (APT) chemical exchange saturation transfer (CEST) MR imaging for brain tumour imaging. In this hybrid MR-PET study, brain tumours were compared using 3D data derived from APT-CEST MRI and amino acid PET using O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET). METHODS: Eight patients with gliomas were investigated simultaneously with 18F-FET PET and APT-CEST MRI using a 3-T MR-BrainPET scanner. CEST imaging was based on a steady-state approach using a B1 average power of 1µT. B0 field inhomogeneities were corrected a Prametric images of magnetisation transfer ratio asymmetry (MTRasym) and differences to the extrapolated semi-solid magnetisation transfer reference method, APT# and nuclear Overhauser effect (NOE#), were calculated. Statistical analysis of the tumour-to-brain ratio of the CEST data was performed against PET data using the non-parametric Wilcoxon test. RESULTS: A tumour-to-brain ratio derived from APT# and 18F-FET presented no significant differences, and no correlation was found between APT# and 18F-FET PET data. The distance between local hot spot APT# and 18F-FET were different (average 20 ± 13 mm, range 4-45 mm). CONCLUSION: For the first time, CEST images were compared with 18F-FET in a simultaneous MR-PET measurement. Imaging findings derived from18F-FET PET and APT CEST MRI seem to provide different biological information. The validation of these imaging findings by histological confirmation is necessary, ideally using stereotactic biopsy.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Glioma/diagnóstico por imagen , Espectroscopía de Protones por Resonancia Magnética , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Protones , Tirosina , Adulto Joven
9.
Stem Cells Int ; 2017: 6319129, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29333166

RESUMEN

Mesenchymal stem cells (MSCs) have been proposed for spinal cord injury (SCI) applications due to their capacity to secrete growth factors and vesicles-secretome-that impacts important phenomena in SCI regeneration. To improve MSC survival into SCI sites, hydrogels have been used as transplantation vehicles. Herein, we hypothesized if different hydrogels could interact differently with adipose tissue-derived MSCs (ASCs). The efficacy of three natural hydrogels, gellan gum (functionalized with a fibronectin peptide), collagen, and a hydrogel rich in laminin epitopes (NVR-gel) in promoting neuritogenesis (alone and cocultured with ASCs), was evaluated in the present study. Their impact on ASC survival, metabolic activity, and gene expression was also evaluated. Our results indicated that all hydrogels supported ASC survival and viability, being this more evident for the functionalized GG hydrogels. Moreover, the presence of different ECM-derived biological cues within the hydrogels appears to differently affect the mRNA levels of growth factors involved in neuronal survival, differentiation, and axonal outgrowth. All the hydrogel-based systems supported axonal growth mediated by ASCs, but this effect was more robust in functionalized GG. The data herein presented highlights the importance of biological cues within hydrogel-based biomaterials as possible modulators of ASC secretome and its effects for SCI applications.

10.
Environ Sci Pollut Res Int ; 24(4): 3506-3518, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27878484

RESUMEN

The treatment of large volumes of olive mill wastewater is presently a challenge. This study reports the technical and economical feasibility of a sequential treatment of olive mill wastewater comprising a dissolved air flotation pre-treatment and nanofiltration. Different pilot nanofiltration assays were conducted in a concentration mode up to different volume reduction factors (29, 45, 58, and 81). Data attained demonstrated that nanofiltration can be operated at considerably high volume reduction factors and still be effective towards the removal of several components. A flux decline of approximately 50% was observed at the highest volume reduction factor, mainly due to increase of the osmotic pressure. Considerably high rejections were obtained across all experiments for total suspended solids (83 to >99%), total organic carbon (64 to 99%), chemical oxygen demand (53 to 77%), and oil and grease (67 to >82%). Treated water was in compliance with European legal limits for discharge regarding total suspended solids and oil and grease. The potential recovery of phenolic compounds was evaluated and found not relevant. It was demonstrated that nanofiltration is economically feasible, involving operation costs of approximately 2.56-3.08 €/m3, depending on the working plan schedule and volume reduction factor, and requiring a footprint of approximately 52 m2 to treat 1000 m3 of olive mill wastewater.


Asunto(s)
Nanotecnología , Olea/química , Aguas Residuales/química , Análisis de la Demanda Biológica de Oxígeno , Filtración , Nanotecnología/economía , Nanotecnología/métodos , Fenoles/análisis , Proyectos Piloto , Eliminación de Residuos Líquidos , Purificación del Agua/economía , Purificación del Agua/métodos
11.
J Endocrinol Invest ; 38(4): 421-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25352236

RESUMEN

BACKGROUND: Epicardial fat thickness (EFT) has been evaluated as a marker of cardiovascular disease, with good correlation with classical cardiovascular risk factors in the general population. The aim of this study was to evaluate the EFT in subclinical hypothyroidism (SCH), in comparison to a group without thyroid dysfunction. METHODS: A cross-sectional study was performed with 100 participants, including 52 SCH patients and 48 individuals without any thyroid dysfunction (euthyroid group-EU). Transthoracic echocardiography (TE), thyroid hormone levels, lipid profile, and assessment of body composition by bioelectrical impedance (BIA) and anthropometry were measured in all subjects. RESULTS: The SCH and EU groups were comparable with respect to age, gender, and Framingham risk scores. Serum thyroid-stimulating hormone (TSH) was 6.7 ± 1.4 mIU/L in the SCH group and 2.0 ± 0.84 mIU/L in the control group. EFT was similar in both groups (SCH 3.5 ± 1.3 mm, EU 3.5 ± 1.1 mm, p = 0.43). EFT showed a slight trend for a positive correlation with serum TSH in the SCH group (r s = 0.263, p = 0.05). EFT correlated with the body fat percentage in the SCH group (r s = 0.350, p = 0.03) and EU group (r s = 0.033, p = 0.04). EFT in this cohort was not independently correlated to changes in TSH and Framingham risk score. CONCLUSIONS: EFT determination by TE does not seem to be a good marker of cardiovascular risk in SCH patients with serum TSH <10.0 mIU/L and no pre-existing cardiovascular morbidity.


Asunto(s)
Adiposidad , Enfermedades Cardiovasculares/diagnóstico por imagen , Hipotiroidismo/diagnóstico por imagen , Pericardio/diagnóstico por imagen , Adulto , Biomarcadores , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/patología , Femenino , Humanos , Hipotiroidismo/sangre , Hipotiroidismo/patología , Masculino , Persona de Mediana Edad , Ultrasonografía
12.
Indoor Air ; 25(1): 105-14, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24735406

RESUMEN

Carbon dioxide (CO2 ) sensors that provide a visual indication were installed in classrooms during normal school operation. During 2-week periods, teachers and students were instructed to open the windows in response to the visual CO2 feedback in 1 week and open them, as they would normally do, without visual feedback, in the other week. In the heating season, two pairs of classrooms were monitored, one pair naturally and the other pair mechanically ventilated. In the cooling season, two pairs of naturally ventilated classrooms were monitored, one pair with split cooling in operation and the other pair with no cooling. Classrooms were matched by grade. Providing visual CO2 feedback reduced CO2 levels, as more windows were opened in this condition. This increased energy use for heating and reduced the cooling requirement in summertime. Split cooling reduced the frequency of window opening only when no visual CO2 feedback was present.


Asunto(s)
Contaminación del Aire Interior/análisis , Dióxido de Carbono/análisis , Monitoreo del Ambiente/métodos , Ventilación , Contaminantes Atmosféricos/análisis , Recursos Audiovisuales , Niño , Dinamarca , Humanos , Instituciones Académicas , Estaciones del Año , Encuestas y Cuestionarios , Temperatura
13.
Arq. bras. med. vet. zootec ; 66(5): 1611-1614, Sep-Oct/2014. tab
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1095994

RESUMEN

From fifteen female dogs with clinical diagnoses of pyometra, hematological exams were performed at three times: M0 (prior to the surgery), M24 (24h after ovarysalpingohisterectomy-OSH) and M48 (48h after OSH). Anemia was seen in 80% of the cases, characterized as mild normocytic normochromic type. The means of total leukocyte counts were 27.043, 57.940 and 40.139 céls/µL in M0, M24 and M48. A total of80% of the animals presented neutrophilic left shift in all moments. During medullar exams, the cellular, iron reserve and megakaryocytic concentration were raised as well as the ME ratio, showing a value of 26,3:1,0, probably due to the elevation of granular proliferation and maturation compartment, as the mean of the reserve compartment was within normal range. As 83% of the animals with neutrophilic left shift showed a melullary reserve compartment raised, it can be concluded that female dogs with piometra had left shift of neutrophils with disproportionally between compartments, without segmented medullar saturation.(AU)


Asunto(s)
Animales , Femenino , Perros , Médula Ósea/patología , Piómetra/veterinaria , Neutrófilos , Recuento de Células Sanguíneas/veterinaria
14.
Lupus ; 23(3): 255-62, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24356611

RESUMEN

Proteinuria is a major feature of lupus nephritis (LN) and reflects podocyte injury. Analysis of podocyte biomarkers was performed attempting to identify if podocyte phenotype is distinct in pure membranous and proliferative LN. Expression of synaptopodin, Wilms tumor protein 1 (WT1), glomerular epithelial protein 1 (GLEPP1) and nephrin was evaluated in 52 LN biopsies by immunohistochemistry. Preserved synaptopodin expression was observed in only 10 (19.2%) of all biopsies while 42 (80.8%) had reduced expression. Both groups had comparable proteinuria at the time of biopsy (p = 0.22); however, in the mean follow-up of four years there was a tendency toward lower mean levels of proteinuria in patients with preserved synaptopodin staining (0.26±0.23 vs. 0.84±0.90 g/24 h, p = 0.05) compared with those with diminished expression. Thirty-nine (75%) biopsies were classified as proliferative and 13 (25%) as pure membranous. Comparison of podocyte biomarkers demonstrated a predominance of preserved staining of synaptopodin (69.2%), WT1 (69.2%), GLEPP1 (53.9%) and nephrin (60%) in the pure membranous group whereas only <10% of the proliferative showed preserved expression. Our data suggest that in proliferative forms there seems to occur structural podocyte damage, whereas in the pure membranous the predominant preserved pattern suggests a dysfunctional podocyte lesion that may account for the better long-term prognosis of proteinuria outcome.


Asunto(s)
Proliferación Celular , Glomerulonefritis Membranoproliferativa/etiología , Glomerulonefritis Membranosa/etiología , Nefritis Lúpica/etiología , Podocitos/patología , Proteinuria/etiología , Adulto , Biomarcadores/análisis , Biopsia , Femenino , Glomerulonefritis Membranoproliferativa/metabolismo , Glomerulonefritis Membranoproliferativa/patología , Glomerulonefritis Membranosa/metabolismo , Glomerulonefritis Membranosa/patología , Humanos , Inmunohistoquímica , Nefritis Lúpica/metabolismo , Nefritis Lúpica/patología , Masculino , Proteínas de la Membrana/análisis , Proteínas de Microfilamentos/análisis , Persona de Mediana Edad , Podocitos/química , Pronóstico , Proteinuria/metabolismo , Proteinuria/patología , Proteínas Tirosina Fosfatasas Clase 3 Similares a Receptores/análisis , Factores de Tiempo , Proteínas WT1/análisis , Adulto Joven
15.
Biochimie ; 95(12): 2297-303, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23851197

RESUMEN

It has been previously shown that the secretome of Human Umbilical Cord Perivascular Cells (HUCPVCs), known for their mesenchymal like stem cell character, is able to increase the metabolic viability and hippocampal neuronal cell densities. However, due to the different micro-environments of the distinct brain regions it is important to study if neurons isolated from different areas have similar, or opposite, reactions when in the presence of HUCPVCs secretome (in the form of conditioned media-CM). In this work we: 1) studied how cortical and cerebellar neuronal primary cultures behaved when incubated with HUCPVCs CM and 2) characterized the differences between CM collected at two different conditioning time points. Primary cultures of cerebellar and cortical neurons were incubated with HUCPVCs CM (obtained 24 and 96 h after three days of culturing). HUCPVCs CM had a higher impact on the metabolic viability and proliferation of cortical cultures, than the cerebellar ones. Regarding neuronal cell densities it was observed that with 24 h CM condition there were higher number MAP-2 positive cells, a marker for fully differentiated neurons; this was, once again, more evident in cortical cultures. In an attempt to characterize the differences between the two conditioning time points a proteomics approach was followed, based on 2D Gel analysis followed by the identification of selected spots by tandem mass spectrometry. Results revealed important differences in proteins that have been previously related with phenomena such as neurl cell viability, proliferation and differentiation, namely 14-3-3, UCHL1, hsp70 and peroxiredoxin-6. In summary, we demonstrated differences on how neurons isolated from different brain regions react to HUCPVCs secretome and we have identified different proteins (14-3-3 and hsp70) in HUCPVCs CM that may explain the above-referred results.


Asunto(s)
Cerebelo/citología , Corteza Cerebral/citología , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical/citología , Proteínas 14-3-3/fisiología , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Medios de Cultivo Condicionados , Femenino , Proteínas HSP70 de Choque Térmico/fisiología , Humanos , Proteínas Asociadas a Microtúbulos/metabolismo , Neuronas/fisiología , Proteómica
16.
Lupus ; 22(9): 899-907, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23857989

RESUMEN

OBJECTIVES: The objective of this paper is to assess the predictors of time-to-lupus renal disease in Latin American patients. METHODS: Systemic lupus erythematosus (SLE) patients (n = 1480) from Grupo Latino Americano De Estudio de Lupus (GLADEL's) longitudinal inception cohort were studied. Endpoint was ACR renal criterion development after SLE diagnosis (prevalent cases excluded). Renal disease predictors were examined by univariable and multivariable Cox proportional hazards regression analyses. Antimalarials were considered time dependent in alternative analyses. RESULTS: Of the entire cohort, 265 patients (17.9%) developed renal disease after entering the cohort. Of them, 88 (33.2%) developed persistent proteinuria, 44 (16.6%) cellular casts and 133 (50.2%) both; 233 patients (87.9%) were women; mean (± SD) age at diagnosis was 28.0 (11.9) years; 12.2% were African-Latin Americans, 42.5% Mestizos, and 45.3% Caucasians (p = 0.0016). Mestizo ethnicity (HR 1.61, 95% CI 1.19-2.17), hypertension (HR 3.99, 95% CI 3.02-5.26) and SLEDAI at diagnosis (HR 1.04, 95% CI 1.01-1.06) were associated with a shorter time-to-renal disease occurrence; antimalarial use (HR 0.57, 95% CI 0.43-0.77), older age at onset (HR 0.90, 95% CI 0.85-0.95, for every five years) and photosensitivity (HR 0.74, 95% CI 0.56-0.98) were associated with a longer time. Alternative model results were consistent with the antimalarial protective effect (HR 0.70, 95% CI 0.50-0.99). CONCLUSIONS: Our data strongly support the fact that Mestizo patients are at increased risk of developing renal disease early while antimalarials seem to delay the appearance of this SLE manifestation. These data have important implications for the treatment of these patients regardless of their geographic location.


Asunto(s)
Antimaláricos/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Nefritis Lúpica/prevención & control , Adolescente , Adulto , Edad de Inicio , Antimaláricos/administración & dosificación , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/epidemiología , América Latina/epidemiología , Estudios Longitudinales , Lupus Eritematoso Sistémico/etnología , Lupus Eritematoso Sistémico/fisiopatología , Nefritis Lúpica/etnología , Masculino , Análisis Multivariante , Trastornos por Fotosensibilidad/epidemiología , Modelos de Riesgos Proporcionales , Análisis de Regresión , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Adulto Joven
17.
Arq. bras. med. vet. zootec ; 64(5): 1256-1264, out. 2012. ilus, tab
Artículo en Portugués | LILACS | ID: lil-655900

RESUMEN

Compararam-se duas diferentes metodologias na avaliação genética de curvas de crescimento de animais Nelore: o algoritmo SAEM e o método Two-step. Para a implementação dessas metodologias, foram utilizados o modelo de crescimento de Brody modificado e o modelo touro. A diferença entre o SAEM e o Two-step é que o algoritmo SAEM estima simultaneamente parâmetros do modelo e efeitos genéticos e ambientais, e o método Two-step faz esse processo de estimação em duas etapas distintas. Mais ainda, o algoritmo SAEM utiliza o método de máxima verossimilhança, e o do Two-step o de máxima verossimilhança restrita. Foram obtidos, com base nas metodologias testadas, além das estimativas de efeitos fixos e parâmetros genéticos, os valores genéticos preditos para os touros avaliados. A partir dos valores genéticos preditos, foram obtidas as curvas genéticas para os touros. O algoritmo SAEM mostrou-se consistente na estimação dos efeitos fixos e na predição dos efeitos aleatórios, apresentando-se como uma alternativa viável para avaliação genética de animais Nelore.


Two methodologies in genetic evaluation of growth curves of Nellore cattle were compared: the SAEM algorithm and the Two Step method. To implement these methodologies the Brody modified growth curve and the sire model were used. The difference between the SAEM and the Two Step is that SAEM estimates jointly the parameters of the model and genetics and environmental effects and the Two Step method does this process in two independent steps. Estimates of the fixed effects and genetics parameters, and prediction breeding values for the sires were obtained from the methodologies. From the breeding values genetic curves were obtained for the sires. The SAEM algorithm proved consistent in the estimation of fixed effects and prediction of random effects.


Asunto(s)
Animales , Bovinos , Algoritmos , Bovinos/genética , Genes , Anotación de Secuencia Molecular
18.
Comput Biol Med ; 42(10): 993-1004, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22964397

RESUMEN

In this work we present HeMoLab (Hemodynamics Modeling Laboratory), a computational environment for modeling the Human Cardiovascular System. Its integrates novel computational tools, running from medical image processing to numerical simulation and visualization. As a simulation tool, it allows to accommodate complex physiological and/or pathophysiological (virtual) scenarios aimed to retrieve detailed information from the numerical computations. Such application makes possible to speed up research in the study and analysis of the cardiovascular system and, to provide a virtual laboratory for medical training and education, and specialized Human Resources development. In order to demonstrate the modeling and simulation capabilities of HeMoLab some cases of use are presented.


Asunto(s)
Fenómenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/anatomía & histología , Hemodinámica/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Modelos Cardiovasculares , Gráficos por Computador , Simulación por Computador , Humanos , Interfaz Usuario-Computador
19.
J Mater Sci Mater Med ; 23(11): 2821-30, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22903600

RESUMEN

Spinal cord injuries (SCI) present a major challenge to therapeutic development due to its complexity. Combinatorial approaches using biodegradable polymers that can simultaneously provide a tissue scaffold, a cell vehicle, and a reservoir for sustained drug delivery have shown very promising results. In our previous studies we have developed a novel hybrid system consisting of starch/poly-e-caprolactone (SPCL) semi-rigid tubular porous structure, based on a rapid prototyping technology, filled by a gellan gum hydrogel concentric core for the regeneration within spinal-cord injury sites. In the present work we intend to promote enhanced osteointegration on these systems by pre-mineralizing specifically the external surfaces of the SPCL tubular structures, though a biomimetic strategy, using a sodium silicate gel as nucleating agent. The idea is to create two different cell environments to promote axonal regeneration in the interior of the constructs while inducing osteogenic activity on its external surface. By using a Teflon cylinder to isolate the interior of the scaffold, it was possible to observe the formation of a bone-like poorly crystalline carbonated apatite layer continuously formed only in the external side of the tubular structure. This biomimetic layer was able to support the adhesion of Bone Marrow Mesenchymal Stem Cells, which have gone under cytoskeleton reorganization in the first hours of culture when compared to cells cultured on uncoated scaffolds. This strategy can be a useful route for locally stimulate bone tissue regeneration and facilitating early bone ingrowth.


Asunto(s)
Materiales Biocompatibles , Regeneración , Traumatismos de la Médula Espinal/fisiopatología , Hidrogeles , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
20.
J Tissue Eng Regen Med ; 5(8): 668-72, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21774090

RESUMEN

Transplantation of bone marrow mesenchymal stem cells (BM-MSCs) has been shown to ameliorate the injured central nervous system (CNS). Although these effects were initially attributed to the putative differentiation of MSCs towards the neural lineage, it is now known that most of them are mediated by the secretome. Up to now most in vitro reports have dealt with the effects of the secretome on neural stem cells and their differentiation. Consequently, there is a lack of information regarding the role of the secretome on the viability and survival of pre-existent matured differentiated cell populations. Moreover, it is also not known how the time points of conditioned media (CM) collection affect such parameters. In the present study, primary cultures of hippocampal neurons and glial cells were incubated with CM obtained from MSCs. To determine how the temporal profiles of CM collection impact on post-natal neurons and glial cells, we collected MSCs CM at 24, 48, 72 and 96 h of conditioning. MTS test revealed that for the hippocampal cultures the incubation with CM increased cell viability for all time points, with significant increases in the percentage of neurons in culture incubated with CM 24 h. For glial cells only the later time point of CM collection (96 h) increased cell viability. Fluorescence microscopy observations also revealed that CM 48 h and 72 h increased astrocytes percentages, while CM 24 h decreased microglial cell and oligodendrocytes values. These results revealed that post-natal neuronal and glial cells respond differently to MSCs CM; moreover, there are specific temporal variations in the composition of the CM of MSCs collected at different time points that trigger different effects on mature neurons and the distinct glial cell populations (astrocytes, oligodendrocytes and microglial cells).


Asunto(s)
Células de la Médula Ósea/metabolismo , Diferenciación Celular/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Neuroglía/citología , Neuronas/citología , Animales , Células de la Médula Ósea/citología , Células Cultivadas , Hipocampo/citología , Células Madre Mesenquimatosas/citología , Neuroglía/efectos de los fármacos , Neuroglía/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratas , Ratas Wistar , Factores de Tiempo
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