High doses of dexamethasone induce increased beta-cell proliferation in pancreatic rat islets

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

Impact of sewage sludge on the soil bacterial communities by DNA microarray analysis

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

Produtividade e qualidade de frutos de mamoeiro ‘sunrise solo’ em função de doses de nitrogênio e boro

The study aimed to evaluate the yield and fruit quality of papaya 'Sunrise Solo' as function of nitrogen and boron fertilization. The experiment had a randomized block design with four replications, two plants per plot with a single border. To make up the treatments, we used the experimental array Plan Puebla III, which set the rates for nitrogen (0.0 to 111.2 - 200 - 288.9 - 400 g plant(-1), and B (0.0 - 0.83 - 1.5 - 2.16 - 3.0 g plant(-1)), in a total of ten treatments. The addition of nitrogen increased the yield, average fruit weight and number of fruits per plant. The nitrogen and boron increased the diameter and length of the fruit, amount of seeds and content of soluble solids. The pH of the pulp decreased linearly with increasing doses of nitrogen and boron. It was observed a significant effect of N rates on the level of vitamin C.

Effects of cumulative doses of vinasse on soil microorganisms in cerrado

Counts of colony forming units of actinomycetes, bacteria and filamentous fungi were determined in cerrado soil treated with vinasse (processed sugar cane effluent) for 5 yr, using doses of 20 l m-2a-1 and 50 l m-2a-1. A temporary increase in the counts of actinomycetes and bacteria for some months after the addition of vinasse was observed. An increased number of fungi was detected throughout the experiment together with qualitative changes in the population. The most abundant fungi in cerrado soil not treated with vinasse (control soil) were Chaetomium, yeasts, Mucor, Penicillium and Trichoderma, while in vinasse treated soils, the same genera adding Verticillium, with the exception of yeasts, were the most common fungi. -Author

The effect of non-antihypertensive doses of angiotensin converting enzyme inhibitor on myocardial necrosis and hypertrophy in young rats with renovascular hypertension

In renovascular hypertensive rats, low doses of angiotensin converting enzyme (ACE) inhibitors have been found to prevent myocardial hypertrophy independent of blood pressure level. This finding would suggest humoral rather than mechanical control of myocyte growth. The aim of this study was to examine the effect of nonantihypertensive doses of ACE inhibitor on myocardial hypertrophy and necrosis in hypertensive rats. Renovascular hypertension (RHT) was induced in four-week-old Wistar rats. Twenty-eight animals were treated for four weeks with three doses of ramipril (0.01, 0.1 or 1.0 mg/kg/day, which are unable to lower blood pressure. Fourteen animals were not treated (RHT group). A sham operated, age/sex-matched group was used as control (n=10). Myocardial histology was analysed in 3 μm thick sections of the ventricle stained with either haematoxylin-eosin, reticulin silver stain or Masson's trichrome. There was a significant correlation between systolic blood pressure and left ventricular to body weight ratio in both sets of animals: untreated plus controls and ramipril-treated rats. ACE inhibition prevented myocyte and perivascular necrosis and fibrosis in a dose-dependent manner. We conclude that myocardial hypertrophy in rats with renovascular hypertension is directly related to arterial pressure, and that this relationship is not affected by nonantihypertensive doses of ACE inhibitor. Myocardial necrosis/fibrosis and coronary artery damage induced by angiotensin II are prevented by ACE inhibitor in a dose-dependent manner, despite the presence of arterial hypertension.

Experimental control of the effect of extra doses of juvenile hormone on bee development: The case of the wax glands of Apis mellifera (Hymenoptera: Apidae)

Experiments on the effect of topical application of the synthetic juvenile hormone (JH-III) and of the solvent used to dissolve the hormone on the development of the wax glands of workers of Apis mellifera, were made. The results show that it was impossible to determine the effect of the juvenile hormone (JH) apart from its solvent (acetone), which also alters the developmental pattern of the gland. Most of the experiments reported in scientific literature do not consider the effect of the solvent, analyzing the results by only comparing the treatment with the hormone plus solvent to a control without any treatment. The data presented suggests that this kind of procedure compromises the evaluation of the real JH effect.

Different doses of exogenous surfactant for treatment of meconium aspiration syndrome in newborn rabbits.

OBJECTIVE: To evaluate the effects of 2 different doses of exogenous surfactant on pulmonary mechanics and on the regularity of pulmonary parenchyma inflation in newborn rabbits. METHOD: Newborn rabbits were submitted to tracheostomy and randomized into 4 study groups: the Control group did not receive any material inside the trachea; the MEC group was instilled with meconium, without surfactant treatment; the S100 and S200 groups were instilled with meconium and were treated with 100 and 200 mg/kg of exogenous surfactant (produced by Instituto Butantan) respectively. Animals from the 4 groups were mechanically ventilated during a 25-minute period. Dynamic compliance, ventilatory pressure, tidal volume, and maximum lung volume (P-V curve) were evaluated. Histological analysis was conducted using the mean linear intercept (Lm), and the lung tissue distortion index (SDI) was derived from the standard deviation of the means of the Lm. One-way analysis of variance was used with a = 0.05. RESULTS: After 25 minutes of ventilation, dynamic compliance (mL/cm H2O.kg) was 0.87 +/- 0.07 (Control); 0.49 +/- 0.04 (MEC*); 0.67 +/- 0.06 (S100); and 0.67 +/- 0.08 (S200), and ventilatory pressure (cm H2O) was 9.0 +/- 0.9 (Control); 16.5 +/- 1.7 (MEC*); 12.4 +/- 1.1 (S100); and 12.1 +/- 1.5 (S200). Both treated groups had lower Lm values and more homogeneity in the lung parenchyma compared to the MEC group: SDI = 7.5 +/- 1.9 (Control); 11.3 +/- 2.5 (MEC*), 5.8 +/- 1.9 (S100); and 6.7 +/- 1.7 (S200) (*P < 0.05 versus all the other groups). CONCLUSIONS: Animals treated with surfactant showed significant improvement in pulmonary mechanics and more regularity of the lung parenchyma in comparison to untreated animals. There was no difference in results after treatment with either of the doses used.

Polymer treatment by plasma immersion ion implantation of nitrogen for formation of diamond-like carbon film

Nitrogen ions were implanted by plasma immersion in Kapton, Mylar and polypropylene, with the objective of forming a diamond-like carbon layer on these polymers. The Raman spectrum of the implanted polypropylene showed typical Diamond-Like Carbon (DLC) graphite (G) and disorder (D) peaks, with an sp 3/sp2 hybridization ratio of approximately 0.4 to 0.6. The XPS analysis of the three implanted polymers also showed peaks of C-C and N-C bonds in the sp3 configuration, with hybridization ratios in the same range as the Raman result. The implanted polymers were exposed to oxygen plasma to test the resistance of the polymers to oxygen degradation. Mass loss rate results, however, showed that the DLC layer formed is not sufficiently robust for this application. Nevertheless, the layer formed can be suitable for other applications such as in gas barriers in beverage containers. Further study of implantation conditions may improve the quality of the DLC layer.

Effects of Plasma Immersion Ion Implantation (PIII) of nitrogen on hardness, composition and corrosion resistance of Ti-6Al-4V alloy

Ti-6Al-4V samples have been treated by PHI processing at different temperatures (400-800°C), treatment time (30-150 min) and plasma potential (100 and 420 V). Hardness measurements results showed an enhancement of the hardness for all implanted samples. XRD results detected the Ti 2N phase and the best corrosion resistance was found for the samples processed at higher temperature and lower PIII time.

Ventricular Systolic Reserve in Asymptomatic Children Previously Treated With Low Doses of Anthracyclines

Doppler echocardiography has been used for the diagnosis of anthracycline-induced cardiotoxicity. However, few data are available that include asymptomatic children previously treated with a low cumulative dose of this drug and therefore have a low risk of cardiac dysfunction. The aim of this study was to evaluate after-exercise cardiac function in asymptomatic children previously treated with a low cumulative dose of anthracycline and no clinical or laboratory evidence of cardiotoxicity. Doppler echocardiography was performed before and immediately after physical exercise in 29 children aged 5 to 17 years (anthracycline [ADRIA] group). All had finished cancer treatment with anthracycline derivatives for ≥1 year (cumulative dose 100 mg/m2). Results were compared with those from age- and gender-matched healthy children (control group; n = 26) using the Mann-Whitney rank test. Exercise-induced cardiac function changes within groups were analyzed using Wilcoxon's signed-rank test. Exercise induced significant increases in left ventricular systolic function indexes in both groups. However, the ADRIA group had significantly lower changes in left ventricular ejection fraction (ADRIA group 0.71 ± 0.02 vs 0.80 ± 0.04 and control group 0.71 ± 0.02 vs 0.89 ± 0.05, p = 0.0017) and end-systolic stress-volume index (ADRIA group 4.59 ± 0.69 vs 6.4 ± 2.0 g.cm-2/ml.m-2 and control group 5.49 ± 0.98 vs 11.54 ± 2.86 g.cm-2/ml.m-2; p <0.0001), indicating decreased functional systolic reserve. In conclusion, asymptomatic children previously treated with low cumulative doses of anthracycline had decreased functional systolic reserve evidenced by exercise, suggesting a nonclinically manifested cardiotoxicity. © 2007 Elsevier Inc. All rights reserved.

Ventricular systolic reserve in asymptomatic children previously treated with low doses of anthracyclines: A longitudinal, prospective exercise echocardiography study

Background: The time course of mild cardiotoxicity induced by anthracycline remains unknown. The aim of this study was to evaluate the long-term evolution of decreased myocardial reserve in children previously treated with a cumulative dose of anthracycline up to 100mg/m 2. Patients and Methods: Twenty-seven asymptomatic cancer survival patients (25 with lymphoblastic leukemia), in continuous remission and off treatment for >12 months with no alterations in conventional echocardiograms were evaluated by exercise echocardiography at 37±15.4 months (T1) and 101±24 months (T2) after finishing treatment (ADRIA group). This group was compared with 25 healthy individuals (control group) similar to the ADRIA group with respect to age and body surface area (BSA). All individuals underwent treadmill exercise testing according to Bruce protocol. Echocardiograms were performed before and immediately after exercise. Results: The groups were similar regarding cardiac structure and left ventricular (LV) systolic function at rest at T1 and T2. The growth of LV posterior wall thickness related to BSA was lower in the ADRIA group at T2. Post exercise, smaller LV ejection indexes and attenuated changes in the afterload in ADRIA group were observed at T1 and T2. Conclusion: The decreased systolic reserve induced by a low dose of anthracycline in asymptomatic children and adolescents remains unaffected over a 5-year period, suggesting that positive outcomes in chronic cardiotoxicity would be expected in patients with mild impairment after anthracycline treatment. © 2011 Wiley Periodicals, Inc.

AMMONIUM AND NITRATE IN SOIL AND RATOON SUGARCANE GROWN IN FUNCTION OF NITROGEN ON OXISOL

After harvest, sugarcane residues left on the soil surface can alter nitrogen (N) dynamics in the plant-soil system. In Oxisols, the nitrogen fertilizer applied had its effects on the levels of ammonium and nitrate in the soil, N concentration in the plant leaves, and on the growth and productivity of second ratoon plants. The N rates tested were of 0, 60, 120, 180, and 240 kg ha-1. Each treatment was replicated four times. Four months after the experiment was started, ammonium and nitrate concentration in the soil, N levels in plant leaves, and plant growth were evaluated. Productivity was evaluated 11 months after the experiment was set. By increasing the content of mineral N in soil, plant growth variables reflected differences in the production of stems; however, it did not affect foliar N. The use of leaf analysis was not important to assess the nutritional status of nitrogen in the ratoon sugarcane. Nitrogen concentration in soil was affected by nitrogen fertilization, but not the N content in leaves. The rate of 138 kg N ha-1enabled greater production of sugarcane stalks (140 t ha-1). © 2013 Copyright Taylor and Francis Group, LLC.