Synthesis, characterization, antibacterial and antitumoral activities of mononuclear zinc complexes containing tridentate amine based ligands with N3 or N2O donor groups

The synthesis and characterization of the four zinc(II) complexes [Zn(HL1)Cl-2] (1), [Zn(H2L2)Cl-2](2), [Zn(H2L3)Cl-2] (3) and[Zn(H2L4)Cl-2] (4), where HL1 = (bis-2-pyridylmethyl)amine, H2L2 = (2-hydroxybenzyl- 2-pyridylmethyl) amine, H2L3 = N-2[(pyridine-2-ylmethyl)amino)ethanol, H2L4 = 1-[(pyridine-2-ylmethyl)- amino]-propan-2-ol are reported; (3) and (4) are new while (2) was reported previously but its structure had not been determined. The complexes were characterized by elemental analysis, IR, UV-Vis and NMR spectroscopic, electrospray ionization mass spectrometry (ESI(+)-MS) and tandem mass spectrometry ESI(+)-MS/MS). X-ray diffraction studies were performed for complexes (1)-(3) revealing the presence of mononuclear structures in the solid state. The X-ray analyses of (1) and (3) demonstrate that HL1 and HL2 act as tridentate ligands, while the ligand H2L2 in (2) is bidentate. The cytotoxic properties of the ligands and of all the complexes were examined using human leukemia THP-1, U937 and Molt-4 cells. Complex (4) exhibited the highest cytotoxicity in this series with an IC50 value of 75 +/- 1 mu mol L (1) against U937 cells. Transmission electron microscopy (TEM) reveals ultrastructural changes typical of apoptotic cells. The induction of apoptosis was confirmed by the annexin V assay. The antimicrobial activity of complexes (1)-(4) was also investigated in vitro against four Gram-positive bacteria (ATCC10832, ATCC25923, COL) and the clinical Staphylococcus aureus isolate LSA88 (SEC/SEF/ TSST-1+). Complex (2) showed the most potent inhibitory activity, reaching almost 100% of inhibition against all strains tested. Morphological investigations using TEM indicate that the antibacterial activity of complex (2) may be associated with the inhibition of cell wall and therefore cell division. (C) 2014 Elsevier B. V. All rights reserved

Analysis of the Intestinal Microbiota of Rainbow Trout (Oncorhynchus Mykiss, Walbaum) and the Aquatic Environment in the Mountain Region of the State of Rio de Janeiro

Truticulture is an activity widely developed activity in the South and Southeast regions of Brazil, including the mountain region of the state of Rio de Janeiro, the target of this study. Antibiotic therapy is used for the prophylaxis and treatment of bacterial diseases. However, these drugs act on commensal and pathogenic bacteria in the intestinal microbiota of healthy and sick fish, which increases the presence of residues in the environment if used indiscriminately, favoring the selective pressure for bacterial resistance to antimicrobials and increasing horizontal transfer of resistance genes among several bacterial populations. The objective of this study was to carry out a survey of cultivable commensal and pathogenic microorganisms in the intestinal content of rainbow trout (Oncorhynchus mykiss) and the aquatic environment for identification of bacteria resistant to antimicrobials and circulating pathogenic factors in the region. Five trout farms were visited. Nine samples of water from the active tanks and 50 fish of the species O. mykiss were collected from July to October and submitted to zootechnical evaluation including the parameters body mass (MC), total length (CT) and standard length (CP). The mean values were 307.15±149.65, 25.79±3.71 and 22.85±3.45, respectively. From the total samples, 222 bacterial isolates were obtained, and the susceptibility profile to antimicrobials was evaluated. Of the total of isolates, 54.5% (n = 121) showed Gram-negative bacteria, especially species from the Enterobacteriaceae, Aeromonaceae and Pseudomonadaceae families; and 45.5% (n = 101) Gram-positive, especially species of the genera Staphylococcus, Enterococcus, Lactococcus, Streptococcus, Kocuria and Gemella. We observed that 65.3% (n = 79) of Gram-negative bacteria and 82.2% (n = 83) of Gram-positive bacteria showed resistance to at least one antimicrobial, and a multidrug resistance profile was observed in 7.4% (n = 9) and 36.6% (n = 37), respectively. Both groups had statistically significant (P<0,05) resistance to beta-lactam antibiotics (p = 0.000; p = 0.045) according to Fisher's exact test. Cephalothin (45.5%), amoxicillin/clavulanic Acid (27.3%), ampicillin (26.5%) and cefoxitin (24,0%) for Gram-negative; amoxicillin and oxacillin (48.5%), ampicillin (42.6%), penicillin G (39.6%), clindamycin (33.7%), gentamicin (28.7%) and tetracycline (27.7%) for Gram-positive. In the molecular analysis, strains of coagulase-negative Staphylococcus spp. (n = 51) were submitted to the PCR technique to detect the methicillin-resistant mecA gene and to detect staphylococcal enterotoxins A, C and D, with the following results: 33.3% (n = 17) positive for the presence of the mecA gene; 98.0% (n = 50) for the sea gene; 9.8% (n = 5) for the sec gene; and 13.7% (n = 7) for the sed gene. Considering the microbiological diversity, resistance profile to antimicrobials associated with virulence factors, it is important to advise producers about adoption of sustainable practices in truticulture, in order to prevent the spread of resistant genes and the consequences to the environment and public health

Development of IgY antibodies in chickens and IgG in rabbits immunized against proteins of Pythium insidiosum isolated from horses in the state of Rio de Janeiro

Pythiosis is caused by Pythium insidiosum and the occurrence of disease in horses was described in the North and Northwest State of Rio de Janeiro, Brazil. The disease was described in cattle, sheep, humans, and horses in different states and regions across the country. This paper describes the development of IgY and IgG polyclonal antibodies, in chicken and rabbits, respectively against proteins extracted from kunkers and hyphae of P. insidiosum from affected horses. The proteins were recognized by chicken, rabbit and horse antibodies by immunodiffusion and Western blot against majority bands of 27 and 43 KDa, and titrated by ELISA. The antibodies IgY developed by the first time against Brazilian strains of P. insidiosum may represent a valuable tool in the detection of antigens of the pathogen and contribute to further studies aimed at immunotherapy and knowledge about this disease in endemic areas in Rio de Janeiro and in Brazil