Efeito da inibição da NADPH oxidase sobre o estresse oxidativo e o fenótipo muscular esquelético de ratos com insuficiência cardíaca crônica induzida por estenose aórtica

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Influence of respiratory biofeedback associated to re-expansive ventilation patterns in individuals with functional mouth breathing

Objectives: Assess the effect of re-expansive respiratory patterns associated to respiratory biofeedback (RBF) on pulmonary function, respiratory muscle strength and habits in individuals with functional mouth breathing (FMB).Methods: Sixty children with FMB were divided into experimental and control groups. The experimental group was submitted to 15 sessions of re-expansive respiratory patterns associated to RBF (biofeedback pletsmovent; MICROHARD (R) V1.0), which provided biofeedback of the thoracic and abdominal movements. The control group was submitted to 15 sessions using biofeedback alone. Spirometry, maximum static respiratory pressure measurements and questions regarding habits (answered by parents/guardians) were carried out before and after therapy. The Student's t-test for paired data and non-parametric tests were employed for statistical analysis at a 5% Level of significance.Results: Significant changes were found in forced vital. capacity, Tiffeneau index scores, maximum expiratory pressure, maximum inspiratory pressure and habits assessed in FMB with the use of RBF associated to the re-expansive patterns. No significant differences were found comparing the experimental and control groups.Conclusions: The results allow the conclusion that RBF associated to re-expansive patterns improves forced vital capacity, Tiffeneau index scores, respiratory muscle strength and habits in FMB and can therefore be used as a form of therapy for such individuals. (C) 2008 Elsevier B.V. All rights reserved.

FUNCTIONAL AND ULTRASTRUCTURAL EVALUATION OF MYOCARDIAL PROTECTION PROVIDED BY INTERMITTENT CORONARY SINUS PERFUSION IN THE ISOLATED DOG HEART

1. The protection offered by intermittent perfusion of of cardioplegic solution through the coronary sinus was investigated in isovolumic blood-perfused dog heart preparations submitted to 60 min of ischemia and 45 min of reperfusion.2. The preparations were divided into three treatment groups: a) coronary sinus, consisting of preparations (N = 10) perfused through the coronary sinus under 40 cm water pressure; b) aortic, consisting of preparations (N = 10) perfused through the aortic stump under 100 mmHg pressure; c) control, consisting of hearts (N = 9) that were not perfused with cardioplegic solution.3. Properties of contractile capacity and relaxation were markedly impaired in the control group but were preserved to a comparable extent in the groups perfused with cardioplegic solution through the aorta and coronary sinus. Developed pressure decreased in the control group (before ischemia: 70 +/- 5.5 mmHg; after reperfusion: 35 +/- 12 mmHg; P < 0.05) and didn't vary in the aortic group (from 69 +/- 4 mmHg to 65 +/- 13 mmHg; P > 0.05) and coronary sinus group (from 69 +/- 4.6 mmHg to 60 +/- 10 mmHg; P > 0.05). Myocardial relaxation was evaluated by the +/- dp/dt ratio. In the control group there was impairment of myocardial relaxation as indicated by an increase of this index after reperfusion (from 1.05 +/- 0.05 to 1.46 +/- 0.23; P < 0.05), whereas in the aortic (from 1.10 +/- 0.13 to 1.15 +/- 0.20; P > 0.05) and the coronary sinus (from 1.03 +/- 0.14 to 1.08 +/- 0.16; P > 0.05) groups there was no variation. Ultrastructural changes in the myocardium were negligible in all three groups at the end of reperfusion.4. We conclude that intermittent perfusion of a hypothermic cardioplegic solution through the coronary sinus is effective for the protection of the myocardium during total ischemia.

Density functional theory study on the structural and electronic properties of low index rutile surfaces for TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 composite systems

The present study is concerned with the structural and electronic properties of the TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 composite systems. Periodic quantum mechanical method with density functional theory at the B3LYP level has been carried out. Relaxed surface energies, structural characteristics and electronic properties of the (I 10), (0 10), (10 1) and (00) low-index rutile surfaces for TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 models are studied. For, comparison purposes, the bare rutile TiO2 and SnO2 structures are also analyzed and compared with previous theoretical and experimental data. The calculated surface energy for both rutile TiO2 and SnO2 surfaces follows the sequence (110) < (010) < (101) < (001) and the energy increases as (010) < (101) < (110) < (001) and (010) approximate to (110) < (101) < (001) for SnO2/TiO2/SnO2 and TiO2/SnO2/TiO2 composite systems, respectively. SnO2/TiO2/SnO2 presents larger values of surface energy than the individual SnO2 and TiO2 metal oxides and the TiO2/SnO2/TiO2 system renders surface energy values of the same order that the TiO2 and lower than the SnO2. An analysis of the electronic structure of the TiO2/SnO2/TiO2 and SnO2/TiO2/SnO2 systems shows that the main characteristics of the upper part of the valence bands for all the studied surfaces are dominated by the external layers, i.e., by the TiO2 and the SnO2, respectively, and the topology of the lower part of the conduction bands looks like the core layers. There is an energy stabilization of both valence band top and conduction band bottom for (110) and (010) surfaces of the SnO2/TiO2/SnO2 composite system in relation to their core TiO2, whereas an opposite trend is found for the same surfaces of the TiO2/SnO2/TiO2 composite system in relation to the bare SnO2. The present theoretical results may explain the growth of TiO2@SnO2 bimorph composite nanotape.

Diastolic function is associated with quality of life and exercise capacity in stable heart failure patients with reduced ejection fraction

Exercise capacity and quality of life (QOL) are important outcome predictors in patients with systolic heart failure (HF), independent of left ventricular (LV) ejection fraction (LVEF). LV diastolic function has been shown to be a better predictor of aerobic exercise capacity in patients with systolic dysfunction and a New York Heart Association (NYHA) classification >II. We hypothesized that the currently used index of diastolic function E/e' is associated with exercise capacity and QOL, even in optimally treated HF patients with reduced LVEF. This prospective study included 44 consecutive patients aged 55±11 years (27 men and 17 women), with LVEF,0.50 and NYHA functional class I-III, receiving optimal pharmacological treatment and in a stable clinical condition, as shown by the absence of dyspnea exacerbation for at least 3 months. All patients had conventional transthoracic echocardiography and answered the Minnesota Living with HF Questionnaire, followed by the 6-min walk test (6MWT). In a multivariable model with 6MWT as the dependent variable, age and E/e' explained 27% of the walked distance in 6MWT (P=0.002; multivariate regression analysis). No association was found between walk distance and LVEF or mitral annulus systolic velocity. Only normalized left atrium volume, a sensitive index of diastolic function, was associated with decreased QOL. Despite the small number of patients included, this study offers evidence that diastolic function is associated with physical capacity and QOL and should be considered along with ejection fraction in patients with compensated systolic HF.

Effect of Fusarium graminearum and infection index on germination and vigor of maize seeds

Patógenos em sementes de milho (Zea mays) causam sérios problemas, como a perda de sua capacidade germinativa. O objetivo do trabalho foi determinar qual o melhor tempo para infecção das sementes de milho com Fusarium graminearum, para posterior avaliação dos danos causados pelo fungo na germinação e vigor das mesmas. As sementes foram colocadas sobre meio de BDA contendo o patógeno e incubadas por 4, 8, 16 e 32 h. Após os respectivos períodos de incubação, estas foram submetidas ao teste de sanidade (papel de filtro), com duas variações, sem e com assepsia superficial, usando hipoclorito de sódio a 1% de cloro ativo, por 3 min. Determinado o melhor tempo para infecção, outras sementes foram infetadas com o patógeno, para realização dos testes de germinação e vigor (envelhecimento acelerado e teste de frio) com uma mistura de sementes sadias (colocadas sobre o meio BDA) e sementes inoculadas, resultando em 0, 20, 40, 60, 80 e 100% de sementes infetadas com o fungo em estudo. Os resultados obtidos mostraram que o período de incubação de 32 h foi suficiente para se obter sementes infetadas. Com relação à germinação, não houve diferenças significativas entre os diferentes níveis de infecção, provavelmente devido ao alto vigor das sementes de milho testadas. Quanto aos testes de vigor, os níveis de infecção diferiram significativamente da testemunha, apesar de não terem diferido entre si.

Thermal study and physico-chemical characterization of some functional properties of guava seeds protein isolate (Psidium guajava)

The guava seed protein isolate ( PI) was obtained from the protein precipitation belonging to the class of the gluteline (Ip 4.5). The conditions for the preparation of the PI were determined by both the solubility curve and simultaneous thermogravimetry-differential thermal analysis (TG-DTA): pH 11.5, absence of NaCl and whiteners and T=( 25 +/- 3) degrees C. Under these conditions a yield of 77.0 +/- 0.4%, protein content of 94.2 +/- 0.3, ashes 0.50 +/- 0.05% and thermal stability, T= 200 degrees C, were obtained. The TG-DTA curves and the PI emulsification capacity study showed the presence of hydrophobic microdomains at pH 11.5 and 3.0 suggesting a random coil protein conformation and, to pH 10.0, an open protein conformation. The capacity of emulsification (CE), in the absence of NaCl, was verified for: 1 - pH 3.0 and 8.5, using the IP extracted at pH 10.0 and 11.5, CE >= 343 +/- 5 g of emulsified oil/g of protein; 2 - pH 6.60 just for the PI obtained at pH 11.5, CE >= 140 +/- 8 g of emulsified oil/g of protein.

Morphological and functional characteristics of chilled semen obtained from domestic feline epididymides (Felis catus)

The objective of this study was to determine morphological and functional characteristics of semen retrieved from the feline epididymis before and after cooling. Sixteen adult male cats were orchiectomized. The distal portion of the epididymis and proximal part of the deferent ducts were dissected and squeezed to obtain their content. After centrifugation, the supernatant was removed, sperm were resuspended in a 0.9 mL Tris-fructose-citric acid extender containing 20% egg yolk, aliquoted into three 0.3 mL samples, placed in a refrigerator (4.8 degrees C) and cooled (0.5 degrees C/min). Semen evaluations were performed on four occassions: immediately after epididymal sperm retrieval (TO), and at 24 h (T-1), 48 h (T-2) and 72 h (T-3) after cooling. on each occasion, progressive motility, vigor and sperm morphology were determined. Mean motility and vigor decreased (P < 0.05) between each successive examination. Although the majority of sperm cell damage occurred within the first 24 h, there was a decrease (P < 0.05) in mean percentage of morphologically normal sperm between To and each evaluated time (T-1, T-2, T-3) after cooling, due to an increase in coiled and bent sperm tails. Further studies are needed to evaluate the effects of cooling on the fertilizing capacity of cat epididymal spermatozoa in assisted reproduction programs. (c) 2006 Elsevier B.V. All rights reserved.

Fertilizing Capacity of Frozen Epididymal Sperm Collected from Dogs

The collection of epididymal sperm may be a valuable tool for canine reproduction especially since it can enable collection of cells after death of a valuable dog. The aim of the present study was to evaluate the viability of epididymal sperm after freeze-thawing. Epididymides were obtained from four adult dogs by elective orchiectomy. The caudal portion of the epididymides and part of the deferential ducts were squeezed by means of an anatomic clamp into a Petri dish containing either 0.9% saline solution (Group 1) or Ringer solution without lactate (Group 2). Samples were centrifuged at 800 x g for 10 min, the supernatant was removed and the pellet was diluted in one step with a Tris/citric acid/OEP (Orvus Es Paste) extender containing 7% glycerol and subjected to semen freezing. Oocytes were obtained from canine ovaries, after ovariohysterectomy. Only oocytes that were approximately 100 mu m in diameter, with a dark ooplasm surrounded by three-or four-well formed cumulus cell layers were used for sperm testing. Frozen semen samples were thawed in a water bath at 70 degrees C for 8 s and analysed at room temperature for sperm motility and velocity. Oocytes were incubated with spermatozoa in humidified atmosphere containing 5% CO(2) at 38 degrees C for 18 h. Morphological and functional characteristics of spermatozoa were similar in both groups. However, the percentage of sperm cells bound to oocytes was significantly higher in Group 2 than in Group 1. This result suggests that the Ringer solution without lactate was a more suitable medium for collecting epididymal canine sperm than 0.9% saline.

Perfil do nível de atividade física na vida diária de pacientes portadores de DPOC no Brasil

Objective: To evaluate characteristics of physical activities in daily life in COPD patients in Brazil, correlating those Characteristics with physiological variables. Methods: Physical activities in daily life were evaluated in 40 COPD patients (18 males; 66 +/- 8 years of age; FEV(1) = 46 +/- 16 % of predicted; body mass index = 27 +/- 6 kg/m(2)) and 30 healthy age- and gender-matched subjects, using a multiaxial accelerometer-based sensor for 12 h/day on two consecutive days. We also assessed maximal and functional exercise capacity, using the incremental exercise test and the six-minute walk test (6MWT), respectively; MIP and MEP; peripheral muscle force, using the one-repetition maximum test and the handgrip test; quality of life, using the Saint George's Respiratory Questionnaire (SGRQ); functional status, using the London Chest Activity of Daily Living questionnaire; and dyspnea sensation, using the Medical Research Council (MRC) scale. Results: Mean walking time/day was shorter for COPD patients than for the controls (55 +/- 33 vs. 80 +/- 28 min/day; p = 0.001), as movement intensity was lower (1.9 +/- 0.4 vs. 2.3 +/- 0.6 m/s(2); p = 0.004). The COPD patients also tended to spend more time seated (294 +/- 114 vs. 246 +/- 122 min/day, p = 0.08). Walking time/day correlated with the 6MWT (r = 0.42; p = 0.007) and maximal workload (r = 0.41; p = 0.009), as well as with age, MRC scale score and SGRQ activity domain score (-0.31 <= r <= -0.43; p <= 0.05 for all). Conclusions: This sample of Brazilian patients with COPD, although more active than those evaluated in studies conducted in Europe, were less active than were the controls. Walking time/day correlated only moderately with maximal and functional exercise capacity.

Functional and Morphological Reproductive Aspects in Male Rats Exposed to Di-n-Butyl Phthalate (DBP) in Utero and During Lactation

The potential adverse reproductive effects, with emphasis on the epididymis, of in utero and lactational exposure to 100 mg/kg/d di-n-butyl phthalate (DBP) in adult male rat offspring were investigated. The fetal testis histopathology was also determined. The selected endpoints included reproductive organ weights, sperm motility and morphology, sperm epididymal transit time, sperm quantity in the testis and epididymis, hormonal status, fetal testis and epididymal histopathology and stereology, and androgen receptor (AR), aquaporin 9 (AQP9), and Ki-67 immunoreactivities. Pregnant females were divided into two groups: control (C) and treated (T). The treated females received DBP (100 mg/kg/d, by gavage) from gestation day (GD) 12 to postnatal day (PND) 21, while control dams received the vehicle. Some pregnant dams were killed by decapitation on GD20, and testes from male fetuses were collected for histopathogy. Male rats from other dams were killed at PND 90. Fetal testes from treated group showed Leydig-cell clusters, presence of multinucleated germinative cells, and increase of the interstitial component. Testosterone levels and reproductive organ weights were similar between the treated and control adult groups. DBP treatment did not markedly affect relative proportions of epithelial, stromal, or luminal compartments in the epididymis; sperm counts in the testis and epididymis; sperm transit time; or sperm morphology and motility in adult rats. The AR and AQP9 immunoreactivities and proliferation index were similar for the two groups. These results showed that fetal testes were affected by DBP as evidenced by testicular histopathologic alterations, but reproductive parameters and epididymal structure/function were not significantly altered in the adult animals exposed to 100 mg/kg DBP in utero and during lactation.

The functional morphology of the metapleural gland of the leaf-cutting ant Atta laevigata (Formicidae: Attini)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Foraging Behavior of the Swarm-founding Wasp Polybia (Trichothorax) sericea (Hymenoptera, Vespidae): Daily Resource Collection Activity and Flight Capacity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Correlation between balance and the level of functional independence among elderly people

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anaerobic capacity may not be determined by critical power model in elite table tennis players

The aim of the present study was to verify the applicability of anaerobic work capacity (AWC) determined from the critical power model in elite table tennis players. Eight male international level table tennis players participated in the study. The tests undertaken were: 1) A critical frequency test used to determinate the anaerobic work capacity; 2) Wingate tests were performed using leg and arm ergometers. AWC corresponded to 99.5 +/- 29.1 table tennis balls. AWC was not related to peak (r = -0.25), mean (r = -0.02), relative peak (r = -0.49) or relative mean power (r = 0.01), nor fatigue index (r = -0.52) (Wingate leg ergometer). Similar correlations for peak (r = -0.34), mean (r = -0.04), relative peak (r = -0.49), relative mean power (r = -0.14) and peak blood lactate concentration (r = -0.08) were determined in the Wingate arm ergometer test. Based on these results the AWC determined by a modified critical power test was not a good index for measurement of anaerobic capacity in table tennis players.