Universidade Federal de Santa Catarina

About: Universidade Federal de Santa Catarina is a education organization based out in Florianópolis, Brazil. It is known for research contribution in the topics: Population & Context (language use). The organization has 28408 authors who have published 55433 publications receiving 714461 citations.

Safety of sputum induction

Abstract: One of the most important recent advances in the investigation of airway inflammation has been the introduction of sputum induction by inhalation of an aerosol of hypertonic saline, by Pin et al. 1 in 1992, to directly obtain airway secretions in asthma. This method has a number of advantages over invasive methods. Safety and practicality are the most obvious. The method of obtaining induced sputum is relatively noninvasive and can be carried out at random 2 and repeatedly in subjects with varying disease severity 3–13. Therefore, it is not surprising that the examination of induced sputum has become the most clinically applicable method for the assessment of airway inflammation. The induction procedure is simple and safe. The risks in patients with stable asthma or chronic obstructive pulmonary disease (COPD) with mild­to­moderate airflow limitation are acceptable 1, 3–5, 8, 12–14. It can also be safe in patients with more severe airflow limitation 6, 10, 11 provided that the induction is performed with caution using a modified procedure 6. The safety of sputum induction has been specifically addressed in several recent publications 3–5, 12, 14. To date, there have been no reports of death or need for hospital admission in patients undergoing sputum induction for the assessment of airway inflammation; the airway constriction caused by sputum induction with hypertonic saline is quickly reversed by treatment with an inhaled short­acting β2‐agonist. It is well known, however, that inhalation of hypertonic or even isotonic saline can cause airway constriction in asthmatic subjects and in COPD, particularly in those with associated airway hyperresponsiveness (AHR). In 1958, Bickerman et al. 15, using aerosols of saline generated by jet nebuliser with concentrations ranging 3.0–15%, observed …

Possible oral transmission of acute Chagas' disease in Brazil

Abstract: In October, 1986, 7 to 22 days after a meeting at a farm in Paraiba state, 26 individuals presented with a febrile illness associated with bilateral eyelid and lower limb edema, mild hepatosplenomegaly, lymphadenopathy and, occasionally a skin rash. A 11-year-old boy exhibited atrial premature complexes and a 74-year-old patient developed acute heart failure. In two patients hospitalized in Sao Paulo city, acute Chagas' disease was diagnosed by the demonstration of circulating Trypanosoma cruzi. At autopsy in a fatal case, acute Chagas' cardiomyopathy was demonstrated. Xenodiagnosis were positive in 9 out of 14 tested patients. A specific IgG immune response was found in all patients and specific IgM antibodies were identified in 20 out of 22 tested patients. A epidemiological survey showed the existence of Triatoma brasiliensis in the outbuildings of this farm, but none in the house where most of the guests stayed. A high rate of infection with Trypanosoma cruzi was found in opossums. These observations together with those related to the food consumed by the patients, lead the authors to suggest that the human infections resulted from oral contamination probably originating from naturally infected marsupials in the area or crushed infected bugs.

Two new ternary complexes of copper(II) with tetracycline or doxycycline and 1,10-phenanthroline and their potential as antitumoral: cytotoxicity and DNA cleavage.

Abstract: This paper reports on the synthesis and characterization of two new ternary copper(II) complexes: [Cu(doxycycline)(1,10-phenanthroline)(H(2)O)(ClO(4))](ClO(4)) (1) and [Cu(tetracycline)(1,10-phenanthroline)(H(2)O)(ClO(4))](ClO(4)) (2). These compounds exhibit a distorted tetragonal geometry around copper, which is coordinated to two bidentate ligands, 1,10-phenanthroline and tetracycline or doxycyline, a water molecule, and a perchlorate ion weakly bonded in the axial positions. In both compounds, copper(II) binds to tetracyclines via the oxygen of the hydroxyl group and oxygen of the amide group at ring A and to 1,10-phenanthroline via its two heterocyclic nitrogens. We have evaluated the binding of the new complexes to DNA, their capacity to cleave it, their cytotoxic activity, and uptake in tumoral cells. The complexes bind to DNA preferentially by the major groove, and then cleave its strands by an oxidative mechanism involving the generation of ROS. The cleavage of DNA was inhibited by radical inhibitors and/or trappers such as superoxide dismutase, DMSO, and the copper(I) chelator bathocuproine. The enzyme T4 DNA ligase was not able to relegate the products of DNA cleavage, which indicates that the cleavage does not occur via a hydrolytic mechanism. Both complexes present an expressive plasmid DNA cleavage activity generating single- and double-strand breaks, under mild reaction conditions, and even in the absence of any additional oxidant or reducing agent. In the same experimental conditions, [Cu(phen)(2)](2+) is approximately 100-fold less active than our complexes. These complexes are among the most potent DNA cleavage agents reported so far. Both complexes inhibit the growth of K562 cells with the IC(50) values of 1.93 and 2.59 μmol L(-1) for compounds 1 and 2, respectively. The complexes are more active than the free ligands, and their cytotoxic activity correlates with intracellular copper concentration and the number of Cu-DNA adducts formed inside cells.