149 resultados para OXYGEN STORAGE
Resumo:
This study aimed to evaluate the second-generation OptiMal test for malaria diagnosis under various storage conditions. It detected all the positive samples, except for two Plasmodium malariae samples. Further research evaluating diverse environmental conditions are important for ICT test applicability in Brazilian malaria areas.
Resumo:
Hyperbaric oxygen has been successfully used on treatment of acute ischemic injuries involving soft tissues and chronic injuries. In nerve crush injuries, the mechanisms involved are very similar to those found in ischemic injuries. Consequently, it is logical to hypothesize that hyperbaric oxygen should improve nerve repair, which is a critical step on functional recovery. In the present study, we created standard nerve crush injuries on sciatic nerves of rats, which underwent treatment with hyperbaric oxygen. Results were assessed by functional evaluation using walking-track analysis. The functional recovery indexes observed did not differ from control group. We concluded that hyperbaric oxygen therapy, in the schedule used, had no influence on functional recovery after nerve crush injuries.
Resumo:
Bacuri (Platonia insignis, Mart.) is one of the most important among Amazonian fruits. However, little is known about its postharvest physiology, such as maturity stages, changes during ambient storage, and respiratory pattern. Fruits were harvested at three maturity stages based on epicarp colour: dark green, light green, and turning (50% yellow), in order to determine colour modification and respiratory pattern during ambient storage (25.2 ºC, 75.1 % RH). Fruit of all maturity stages showed, after three days of harvest, a non-climacteric respiratory pattern, with turning fruit presenting the highest CO2 production rate until the fourth storage day (177.63 mg.CO2.kg-1.h-1). Yellowing increased throughout storage as related to lightness, chromaticity, and hue angle reductions. Turning fruit can be stored at ambient conditions for up to 10 days without any loss in marketability.
Resumo:
PURPOSE: To compare peak exercise oxygen consumption (VO2peak) of healthy individuals with asymptomatic individuals with probable heart disease. METHODS: Ninety-eight men were evaluated. They were divided into two groups: 1) 39 healthy individuals (group N) with an age range of 50±4.6 years; and 2) 59 asymptomatic individuals with signs of atherosclerotic and/or hypertensive heart disease (group C) with an age range of 51.9±10.4 years. In regard to age, height, body surface area, percentage of fat, lean body mass, and daily physical activity, both groups were statistically similar. Environmental conditions during the ergometric test were also controlled. RESULTS: Maximal aerobic power (watts), VO2peak, maximal heart rate, and maximal pulmonary ventilation were lower in group C (p<0.01) than in group N; weight, however, was lower in group N (p=0.031) than in group C. Differences in the respiratory gas exchange index, heart rate at rest, and the maximal double product of the two groups were not statistically significant. CONCLUSION: Signs of probable heart disease, even though asymptomatic, may reduce the functional capacity, perhaps due to the lower maximal cardiac output and/or muscle metabolic changes.
Resumo:
OBJECTIVE: To compare the effects of 3 types of noninvasive respiratory support systems in the treatment of acute pulmonary edema: oxygen therapy (O2), continuous positive airway pressure, and bilevel positive pressure ventilation. METHODS: We studied prospectively 26 patients with acute pulmonary edema, who were randomized into 1 of 3 types of respiratory support groups. Age was 69±7 years. Ten patients were treated with oxygen, 9 with continuous positive airway pressure, and 7 with noninvasive bilevel positive pressure ventilation. All patients received medicamentous therapy according to the Advanced Cardiac Life Support protocol. Our primary aim was to assess the need for orotracheal intubation. We also assessed the following: heart and respiration rates, blood pressure, PaO2, PaCO2, and pH at begining, and at 10 and 60 minutes after starting the protocol. RESULTS: At 10 minutes, the patients in the bilevel positive pressure ventilation group had the highest PaO2 and the lowest respiration rates; the patients in the O2 group had the highest PaCO2 and the lowest pH (p<0.05). Four patients in the O2 group, 3 patients in the continuous positive pressure group, and none in the bilevel positive pressure ventilation group were intubated (p<0.05). CONCLUSION: Noninvasive bilevel positive pressure ventilation was effective in the treatment of acute cardiogenic pulmonary edema, accelerated the recovery of vital signs and blood gas data, and avoided intubation.
Resumo:
Background: The equations predicting maximal oxygen uptake (VO2max or peak) presently in use in cardiopulmonary exercise testing (CPET) softwares in Brazil have not been adequately validated. These equations are very important for the diagnostic capacity of this method. Objective: Build and validate a Brazilian Equation (BE) for prediction of VO2peak in comparison to the equation cited by Jones (JE) and the Wasserman algorithm (WA). Methods: Treadmill evaluation was performed on 3119 individuals with CPET (breath by breath). The construction group (CG) of the equation consisted of 2495 healthy participants. The other 624 individuals were allocated to the external validation group (EVG). At the BE (derived from a multivariate regression model), age, gender, body mass index (BMI) and physical activity level were considered. The same equation was also tested in the EVG. Dispersion graphs and Bland-Altman analyses were built. Results: In the CG, the mean age was 42.6 years, 51.5% were male, the average BMI was 27.2, and the physical activity distribution level was: 51.3% sedentary, 44.4% active and 4.3% athletes. An optimal correlation between the BE and the CPET measured VO2peak was observed (0.807). On the other hand, difference came up between the average VO2peak expected by the JE and WA and the CPET measured VO2peak, as well as the one gotten from the BE (p = 0.001). Conclusion: BE presents VO2peak values close to those directly measured by CPET, while Jones and Wasserman differ significantly from the real VO2peak.
Resumo:
AbstractBackground:Aerobic fitness, assessed by measuring VO2max in maximum cardiopulmonary exercise testing (CPX) or by estimating VO2max through the use of equations in exercise testing, is a predictor of mortality. However, the error resulting from this estimate in a given individual can be high, affecting clinical decisions.Objective:To determine the error of estimate of VO2max in cycle ergometry in a population attending clinical exercise testing laboratories, and to propose sex-specific equations to minimize that error.Methods:This study assessed 1715 adults (18 to 91 years, 68% men) undertaking maximum CPX in a lower limbs cycle ergometer (LLCE) with ramp protocol. The percentage error (E%) between measured VO2max and that estimated from the modified ACSM equation (Lang et al. MSSE, 1992) was calculated. Then, estimation equations were developed: 1) for all the population tested (C-GENERAL); and 2) separately by sex (C-MEN and C-WOMEN).Results:Measured VO2max was higher in men than in WOMEN: -29.4 ± 10.5 and 24.2 ± 9.2 mL.(kg.min)-1 (p < 0.01). The equations for estimating VO2max [in mL.(kg.min)-1] were: C-GENERAL = [final workload (W)/body weight (kg)] x 10.483 + 7; C-MEN = [final workload (W)/body weight (kg)] x 10.791 + 7; and C-WOMEN = [final workload (W)/body weight (kg)] x 9.820 + 7. The E% for MEN was: -3.4 ± 13.4% (modified ACSM); 1.2 ± 13.2% (C-GENERAL); and -0.9 ± 13.4% (C-MEN) (p < 0.01). For WOMEN: -14.7 ± 17.4% (modified ACSM); -6.3 ± 16.5% (C-GENERAL); and -1.7 ± 16.2% (C-WOMEN) (p < 0.01).Conclusion:The error of estimate of VO2max by use of sex-specific equations was reduced, but not eliminated, in exercise tests on LLCE.
Resumo:
Abstract Background: Prolonged aerobic exercise, such as running a marathon, produces supraphysiological stress that can affect the athlete's homeostasis. Some degree of transient myocardial dysfunction ("cardiac fatigue") can be observed for several days after the race. Objective: To verify if there are changes in the cardiopulmonary capacity, and cardiac inotropy and lusitropy in amateur marathoners after running a marathon. Methods: The sample comprised 6 male amateur runners. All of them underwent cardiopulmonary exercise testing (CPET) one week before the São Paulo Marathon, and 3 to 4 days after that race. They underwent echocardiography 24 hours prior to and immediately after the marathon. All subjects were instructed not to exercise, to maintain their regular diet, ingest the same usual amount of liquids, and rest at least 8 hours a day in the period preceding the CPET. Results: The athletes completed the marathon in 221.5 (207; 250) minutes. In the post-marathon CPET, there was a significant reduction in peak oxygen consumption and peak oxygen pulse compared to the results obtained before the race (50.75 and 46.35 mL.kg-1 .min-1; 19.4 and 18.1 mL.btm, respectively). The echocardiography showed a significant reduction in the s' wave (inotropic marker), but no significant change in the E/e' ratio (lusitropic marker). Conclusions: In amateur runners, the marathon seems to promote changes in the cardiopulmonary capacity identified within 4 days after the race, with a reduction in the cardiac contractility. Such changes suggest that some degree of "cardiac fatigue" can occur.
Resumo:
Eosinophils are prominent inflammatory cells in asthma and other allergic disorders, as well as in helminthic parasite infections. Recently, eosinophils have been reported to synthesize and store a range of regulatory proteins within their secretory granules (eokines). Eokines comprise a group of cytokines, chemokines, and growth factors which are elaborated by eosinophils. These proteins, and the messages which encode them, appear to be identical to those produced by lymphocytes and other tissues. Interestingly, immunoreactivity to many of these eokines has been found to co-localize to the eosinophil´s secretory granules. In this review, we have discussed the repertoire of 18 eokines so far identified in eosinophils, and focused on four of these, namely, interleukin-2 (IL-2), IL-4, granulocyte/macrophage colony-stimulating factor (GM-CSF), and RANTES. These four eokines co-localize to the crystalloid granules in eosinophils, as shown in studies using subcellular fractionation and immunogold labeling in electron microscopy. During stimulation by physiological triggers, for example, with serum-coated particles, eosinophils release these mediators into the surrounding supernatant. In addition, eokines are likely to be synthesized within eosinophils rather than taken up by endocytosis, as show in detection of mRNA for each of these proteins using in situ hybridization, RT-PCR, and in the case of RANTES, in situ RT-PCR. Eokines synthesis and release from eosinophils challenges the commonly held notion that these cells act downstream of key elements in immune system, and indicate that they may instead belong to the afferent arm of immunity.
Resumo:
The metabolisms of reactive nitrogen and oxygen intermediates (RNI and ROI) in patients with cutaneous leishmaniasis (CL) were investigated and compared with those of healthy subjects. To determine RNI metabolism, nitrite plus nitrate concentrations were measured spectrophotometrically. Nitrite concentration in plasma was determined directly by the Griess method. Nitrate levels in plasma were measured after reduction into nitrite by using copper-cadmium-zinc. ROI metabolism was evaluated by measuring erythrocyte superoxide dismutase, catalase and glutathione peroxidase activities. Plasma nitrite plus nitrate levels and erythrocyte superoxide dismutase activity were higher in the patient group than healthy subjects (p<0.01). In contrast, erythrocyte catalase and glutathione peroxidase activities were lower (p<0.05, p<0.01, respectively). ROI metabolism was altered in relation to hydrogen peroxide elevation in patients with CL. These alterations in ROI enable nitric oxide (NO) to amplify its leishmanicidal effect. The determination of ROI and RNI in patients with CL may be a useful tool to evaluate effector mechanisms of NO and clinical manifestations.
Resumo:
The aim of this study was to compare the efficacy of conservation by freezing the strains of Haemophilus influenzae at -20ºC and -70ºC. Skim milk supplemented with glucose, yeast extract and glycerol allowed highest viability of H. influenzae both at -20ºC and -70ºC from the media analyzed. Trypticase soy broth and brain heart infusion broth supplemented with glycerol, allowed excellent recovery. Use of cotton swaps as supporting material, with or without addition of cryoprotective agents, did not modify H. influenzae viability after six months of storage. Concentration of the initial inoculum positively affected viability when stored at -20ºC. Initial concentration did not influence survival after storage at -70ºC. Thawing at room temperature should not exceed 3 h as to get highest survival percentage.
Resumo:
The viability of Ochlerotatus albifasciatus (Macquart) eggs stored at room temperature and at 5ºC was studied over 31 months. After 12, 18 and 31 months of storage, eggs were acclimatized at 22ºC for ten days, and then inundated twice every seven days. The effect of the storage period on the percentage of hatching was analyzed by one way ANOVA. Differences on the hatching response between the first and second flooding were analyzed by paired t-test. Differences on the hatching response between the two storage conditions were analyzed by Mann-Whitney rank test. Results showed that (1) Oc. albifasciatus eggs were able to survive and hatch over 31 months; (2) the percent hatching of eggs stored at 5ºC was higher than that of eggs stored at room temperature; and (3) low temperatures and long periods without water favor installment hatching.
Resumo:
Stool is chemically complex and the extraction of DNA from stool samples is extremely difficult. Haemoglobin breakdown products, such as bilirubin, bile acids and mineral ions, that are present in the stool samples, can inhibit DNA amplification and cause molecular assays to produce false-negative results. Therefore, stool storage conditions are highly important for the diagnosis of intestinal parasites and other microorganisms through molecular approaches. In the current study, stool samples that were positive for Giardia intestinalis were collected from five different patients. Each sample was stored using one out of six different storage conditions [room temperature (RT), +4ºC, -20ºC, 70% alcohol, 10% formaldehyde or 2.5% potassium dichromate] for DNA extraction procedures at one, two, three and four weeks. A modified QIAamp Stool Mini Kit procedure was used to isolate the DNA from stored samples. After DNA isolation, polymerase chain reaction (PCR) amplification was performed using primers that target the β-giardin gene. A G. intestinalis-specific 384 bp band was obtained from all of the cyst-containing stool samples that were stored at RT, +4ºC and -20ºC and in 70% alcohol and 2.5% potassium dichromate; however, this band was not produced by samples that had been stored in 10% formaldehyde. Moreover, for the stool samples containing trophozoites, the same G. intestinalis-specific band was only obtained from the samples that were stored in 2.5% potassium dichromate for up to one month. As a result, it appears evident that the most suitable storage condition for stool samples to permit the isolation of G. intestinalis DNA is in 2.5% potassium dichromate; under these conditions, stool samples may be stored for one month.
Resumo:
Soil water storage of Central Amazonian soil profiles in upland forest plots subjected to selective logging (in average, 8 trees or 34, 3 m³ of timber per hectare were removed) was measured in four layers, down to a depth of 70 cm. The study lasted 27-months and was divided in two phases: measurements were carried out nearly every week during the first 15 months; in the following year, five intensive periods of measurements were performed. Five damage levels were compared: (a) control (undisturbed forest plot); (b) centre of the clearing/gap; (c) edge of the gap; (d) edge of the remaining forest; and (e) remaining forest. The lowest values for water storage were found in the control (296 ± 19.1 mm), while the highest were observed (333 ± 25.8 mm) in the centre of the gap, during the dry period. In the older gaps (7.5-8.5 year old), soil water storage was similar to the remaining and the control forest, indicating a recovery of hydric soil properties to nearly the levels prior to selective logging.