ACUTE TOXICITY and ENVIRONMENTAL RISK of OXYTETRACYLINE and FLORFENICOL ANTIBIOTICS TO PACU (Piaractus mesopotamicus)

The oxytetracyline (OTC) and florfenicol (FLO) are the most used antibiotics for bacterial disease control in fish. The aims are: estimating the lethal concentration 50% initial (LC(I) 50;48h) of OTC (Terramicina (R)) and FLO (Aquaflor (R)) for pacu (Piaractus mesopotamicus); classifying OTC and FLO according to the acute toxicity and the risk of environmental intoxication; and assessing OTC and FLO dilution effect in water quality variables. Fish were acclimatized for 10 days in a bioassay room at 27 +/- 2 degrees C. Then nine animals (three each concentration) were exposed to 7.0; 7.5; 8.0 or 8.5 mg L(-1) of OTC or to 600.0; 700.0; 800.0; 900.0 and 1000.0 mg L(-1) of FLO and a control treatment. The water quality variables recorded daily were: pH, temperature, electric conductivity, and dissolved oxygen. OTC and FLO were classified according to acute toxicity and environmental risk. The estimated OTC LC(I) 50;48h for pacu is 7.6 mg L(-1) and the estimated FLO is > 1000 mg L(-1). OTC reduced the dissolved oxygen concentration, and it was considered moderately toxic, causing risk of environmental intoxication to pacu. FLO is not toxic; it does not cause risk of environmental intoxication to pacu and does not change water quality variables.

Detached leaf culture: Viability to evaluate 2,4-D toxicity symptoms in cotton apex leaves

To study the viability of detached leaf culture technique, studies were carried out with detached leaves from cotton apex (true trilobed leaves). The prepared leaves were sprayed with 2,4-D amine and ester, at rates of 10, 30, 70, and 100% of the recommended doses. Detached leaves without herbicide spray were used as controls. Simultaneously, a greenhouse experiment was conducted with the same treatments as used for the detached leaves experiment. Toxicity was measured through a 0-to-5 grading according to the percentage of affected leaf area in the detached leaves experiment or examining the affected rate of whole plant as indicated in the greenhouse. Results showed that the ester form of the herbicide induced earlier and more severe toxicity symptoms in detached leaves and greenhouse grown plants. Positive and significant correlations (p < 0.001) were found between toxicity results obtained at 7 and 14 days after application in detached leaves and greenhouse plants (r = 0.97 and 0.92, respectively). Negative, significant correlations (p < 0.005) were found between the toxicity levels found at 7 and 14 days after application in detached leaves and dry matter of cotton plants grown in the greenhouse (r = -0.92 and -0.92, respectively).

The role of nitric oxide in the regulation of the systemic and pulmonary vasculature of the rattlesnake, Crotalus durissus terrificus

The functional role of nitric oxide (NO) was investigated in the systemic and pulmonary circulations of the South American rattlesnake, Crotalus durissus terrificus. Bolus, intra-arterial injections of the NO donor, sodium nitroprusside (SNP) caused a significant systemic vasodilatation resulting in a reduction in systemic resistance (Rsys). This response was accompanied by a significant decrease in systemic pressure and a rise in systemic blood flow. Pulmonary resistance (Rpul) remained constant while pulmonary pressure (Ppul) and pulmonary blood flow (Qpul) decreased. Injection of L-Arginine (L-Arg) produced a similar response to SNP in the systemic circulation, inducing an immediate systemic vasodilatation, while Rpul was unaffected. Blockade of NO synthesis via the nitric oxide synthase inhibitor, L-NAME, did not affect haemodynamic variables in the systemic circulation, indicating a small contribution of NO to the basal regulation of systemic vascular resistance. Similarly, Rpul and Qpul remained unchanged, although there was a significant rise in Ppul. Via injection of SNP, this study clearly demonstrates that NO causes a systemic vasodilatation in the rattlesnake, indicating that NO may contribute in the regulation of systemic vascular resistance. In contrast, the pulmonary vasculature seems far less responsive to NO.

Influence of pursed-lip breathing on heart rate variability and cardiorespiratory parameters in subjects with chronic obstructive pulmonary disease (COPD)

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

Step Counting and Energy Expenditure Estimation in Patients With Chronic Obstructive Pulmonary Disease and Healthy Elderly: Accuracy of 2 Motion Sensors

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estimation of Maximal Work Rate Based on the 6-Minute Walk Test and Fat-Free Mass in Chronic Obstructive Pulmonary Disease

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

Is walking in daily life a moderate intensity activity in patients with chronic obstructive pulmonary disease?

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

Fractal correlation property of heart rate variability in chronic obstructive pulmonary disease

Background: It was reported that autonomic nervous system function is altered in subjects with chronic obstructive pulmonary disease (COPD). We evaluated short-and long-term fractal exponents of heart rate variability (HRV) in COPD subjects.Patients and methods: We analyzed data from 30 volunteers, who were divided into two groups according to spirometric values: COPD (n = 15) and control (n = 15). For analysis of HRV indices, HRV was recorded beat by beat with the volunteers in the supine position for 30 minutes. We analyzed the linear indices in the time (SDNN [standard deviation of normal to normal] and RMSSD [root-mean square of differences]) and frequency domains (low frequency [LF], high frequency [HF], and LF/HF), and the short-and long-term fractal exponents were obtained by detrended fluctuation analysis. We considered P < 0.05 to be a significant difference.Results: COPD patients presented reduced levels of all linear exponents and decreased short-term fractal exponent (alpha-1: 0.899 +/- 0.18 versus 1.025 +/- 0.09, P = 0.026). There was no significant difference between COPD and control groups in alpha-2 and alpha-1/alpha-2 ratio.Conclusion: COPD subjects present reduced short-term fractal correlation properties of HRV, which indicates that this index can be used for risk stratification, assessment of systemic disease manifestations, and therapeutic procedures to monitor those patients.

Induction of apoptosis in A549 pulmonary cells by two Paracoccidioides brasiliensis samples

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effects and toxicity of Eugenia punicifolia extracts in streptozotocin-diabetic rats

Extracts and decoctions of Eugenia jambolana Lam., Eugenia uniflora L., and Eugenia punicifolia (Humb., Bonpl. & Kunt) DC. are used in traditional medicine to treat diabetes mellitus. Although there have been reports that Eugenia jambolana and Eugenia uniflora have antidiabetic effects, no study has yet been made on Eugenia punicifolia . We investigated the effects of aqueous, butanol, and methanol extracts of Eugenia punicifolia leaves administered by gavage to streptozotocin-diabetic rats for 26 to 29 days. Body weight, food and fluid intake, urine volume, and urinary glucose and urea were evaluated every 7 days. At the end of the experiment, we measured serum cholesterol, high-density lipoprotein (HDL)-cholesterol, triglycerides and bilirubin, hepatic glycogen and serum marker-enzymes (alanine and aspartate aminotransferases, alkaline phosphatase, gamma-glutamyltransferase, L-lactate dehydrogenase, creatine kinase, alpha-amylase, and angiotensin I converting enzyme). We found that in rats treated with the aqueous extracts, food and liquid intake, urinary volume, and body weight were all reduced, while for rats treated with the methanol extract, not only were liquid intake, urinary volume and body weight reduced, but urinary glucose and urea also decreased. Rats treated with the butanol extract showed no significant alterations in any of the parameters measured. Chronic treatment with extracts had no effect on the marker enzymes nor on serum bilirubin levels. The results indicate that aqueous extracts of Eugenia punicifolia leaves produced an anorexic effect and that methanol extracts had a beneficial effect on the diabetic state by improving carbohydrate and protein metabolism without provoking hepatobiliary, microvascular, muscular, or pancreatic toxic effects.

Acute, subacute toxicity and genotoxic effect of a hydroethanolic extract of the cashew (Anacardium occidentale L.)

Anacardium occidentale L. (Anacardiaceae), popularly known as cajueiro is a native plant to Brazil, and largely used in popular medicine to treat ulcers, hypertension and diarrhea. In the present study, acute, 30-day subacute toxicity and genotoxicity assays were carried out. The crude extract did not produce toxic symptoms in rats in doses up to 2000 mg/kg. Based on biochemical analyses of renal and hepato-biliary functions, such as the level of urea, creatinine, transaminases and alkaline phosphatase, we determined that the extract is generally tolerated by rats. This was also confirmed by hematological and histopathological exams. Genotoxicity was accessed by the Ames test in Salmonella typhimurium strains TA97, TA98, TA 100, TA 102 and by the bone marrow micronucleus test in mice. The extract was shown to induce frameshift, base pair substitution and damage to the chromosomes. However, this effect was less deleterious than the clastogenic effect of ciclophosphamide. (c) 2006 Elsevier B.V.. All rights reserved.

Amphotericin B Microemulsion Reduces Toxicity and Maintains the Efficacy as an Antifungal Product

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Protection of insulin-producing cells against toxicity of dexamethasone by catalase overexpression

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