Hypertension depresses but exercise training restores both Mfsd2a expression and blood-brain barrier function within PVN capillaries.

Hypertension augments while exercise training corrects the increased vesicle trafficking (transcytosis) across the blood-brain barrier (BBB) within preautonomic areas and the autonomic imbalance. There is no information on a possible mechanism(s) conditioning these effects. Knowing that Mfsd2a is the major transporter of docosahexaenoic acid (DHA) and that Mfsd2a knockout mice exhibited leaky BBB, we sought to identify its possible involvement in hypertension- and exercise-induced transcytosis across the BBB. Spontaneously hypertensive rats (SHR) and Wistar rats were submitted to treadmill training (T) or kept sedentary (S) for 4 wk. Resting hemodynamic/autonomic parameters were recorded in conscious chronically cannulated rats. BBB permeability within the hypothalamic paraventricular nucleus (PVN) was evaluated in anesthetized rats. Brains were harvested for Mfsd2a and caveolin-1 (an essential protein for vesicle formation) expression. SHR-S versus Wistar-S exhibited elevated arterial pressure (AP) and heart rate (HR), increased vasomotor sympathetic activity, reduced cardiac parasympathetic activity, greater pressure variability, reduced HR variability, and depressed baroreflex control. SHR-S also showed increased BBB permeability, reduced Mfsd2a, and increased caveolin-1 expression. SHR-T versus SHR-S exhibited increased Mfsd2a density, reduced caveolin-1 protein expression, and normalized PVN BBB permeability, which were accompanied by resting bradycardia, partial AP drop, reduced sympathetic and normalized cardiac parasympathetic activity, increased HR variability, and reduced pressure variability. No changes were observed in Wistar-T versus Wistar-S. Training is an efficient tool to rescue Mfsd2a expression, which by transporting DHA into the endothelial cell reduces caveolin-1 availability and vesicles' formation. Exercise-induced Mfsd2a normalization is an important mechanism to correct both BBB function and autonomic control in hypertensive subjects.

Impact of the content and size of NaCl on dynamic sensory profile and instrumental texture of beef burgers.

The objectives of this study were to determine the effect of reducing the content and size of NaCl on the instrumental texture and dynamic sensory profile, and to determine the temporal drivers of liking (TDL). The reduction of the NaCl content decreased the hardness and chewiness parameters, and affected the dynamic sensory profile of the product. The NaCl reduction (<1.0% NaCl) was related to a higher incidence of the attributes off-flavor and dry. In general, the overall liking was driven by the juicy and tasty attributes, the latter being associated with the presence of the sensory attributes salty and seasoned and the texture parameters hardness and chewiness. According to the results, among the treatments with NaCl reduction, the beef burger added with 1.0% micronized salt stood out, since it did not affect considerably the texture parameters, the dynamic sensory profile during chewing and the consumers' liking.

Bleaching effects on shear bond strengths of orthodontic brackets.

OBJECTIVES: The purpose of this research was to investigate the influence of 35% hydrogen peroxide on orthodontic bracket adhesion at zero hour, 24 hours, 7, 21 and 56 days after dental bleaching. MATERIALS AND METHODS: Ninety bovine incisors were prepared for adhesion test and adhesive remnant index (ARI) determination. The 35% hydrogen peroxide was used as a bleaching agent and the Transbond XT as a bonding agent. RESULTS: Statiscally significant differences were observed between all the groups (p<0.001) and were observed in the comparison of zero hour and control group (p<0.001) and in the comparison of zero hour and 24 hours (p<0.001). ARI scores (0, 1, 2 e 3) also showed statiscally differences between all the groups (p=0.011) and at the comparison of all the test groups with the control: zero hour (p=0.001), 24 hours (p=0.009), 7 days (p=0.018), 21 days (p<0.001) e 56 days (p=0.004). CONCLUSIONS: The shear bond strength values became significantly lower when the bracket was bonded immediately after bleaching and quickly returned to control level in 24 hours. In seven days, there was a slight increase that was not significant and recovered to normal values in the next weeks. Different patterns of fractures were observed in bleached enamel when ARI scores were analyzed. The control group showed a high frequency of 3 score and none of zero score, the opposite behavior was observed in the test groups.

Friction generated by elastomeric ligature with and without polymercoating / Atrito gerado por ligaduras elásticas com e sem cobertura polimérica

The purpose of this study was to compare, in vitro, the friction generated by elastomeric ligature with polymer coating to conventional elastomeric ligature. Three calipers of stainless steel wire were tested: 0.020”, 0.019” x 0.025” and 0.019” x 0.026 “. Two acrylic plates were manufactured. An upper central incisor bracket was fixed to one of them and a canal (or groove) – where orthodontic wires were fixed – was made on the other. The acrylic plates were adapted and adjusted to a traction test machine so that the wire would fit into the bracket slot without any angulation. Ten ligatures of each kind were tested for each wire. The wires were pulled and slid into the bracket for a distance of 5mm at a constant rate of 5mm/min. The obtained data was compared by Student´s T test with the significance value of p<0.05 and revealed the existence of great differences between the forces generated for each wire caliper. The conventional ligatures without polymer coating generated significantly higher forces than the ligatures with coating. The polymer-coated ligatures generated lower friction than the conventional ligature in all calipers evaluated. That suggests that this type of ligature should be the best choice for sliding mechanism

O objetivo deste estudo foi comparar, in vitro, o atrito gerado por ligaduras elásticas com cobertura polimérica com ligaduras convencionais. Três calibres de fio de aço inoxidável foram testados: 0.020”, 0.019” x 0.025” and 0.019” x 0.026 “. Foram confeccionadas duas placas de acrílico, onde em uma placa foi colado um bráquete de incisivo central superior e na outra placa foi feita uma canaleta onde os fios ortodônticos foram fixados. As placas de acrílico foram adaptadas e reguladas em uma máquina de ensaio de tração de maneira que o fio se encaixasse no bráquete sem nenhuma angulação. Para cada fio foram testadas 10 ligaduras de cada tipo. Os fios foram tracionados, deslizando pelo slot do bráquete a uma distância de 5mm com uma velocidade constante de 5mm/min. Os resultados obtidos foram comparados pelo teste t de Student com significância de p<0.05, e revelaram a existência de diferenças significativas entre as forças geradas para cada calibre de fio. As ligaduras convencionais sem cobertura polimérica geraram forças significativamente maiores que as ligaduras com cobertura polimérica. As ligaduras com cobertura polimérica geraram menor atrito que as ligaduras convencionais em todos os calibres de fio avaliados, sugerindo que estas ligaduras devem ser o material de escolha nas mecânicas de deslizamento.