Nasal isolates of commensal Staphylococcus aureus and non-aureus species from healthy young adults in Valencia (Spain) and their resistance to chemotherapeutic agents

Fluoroquinolones are critical antimicrobials for both human and veterinary medicine. Due to their unique mechanism of antimicrobial action and good pharmacokinetic properties, they are often the first choice drugs in the treatment of bacterial infections in animals. The purpose of the investigation was to study the antimicrobial activity of a third-generation fluoroquinolone antibiotic of danofloxacin against bacteria, pathogens of respiratory and intestinal infection in goats. The samples of the nasal outflows (respiratory infection) and fecal masses (intestinal infection) were collected from clinically ill goats for microbiological studies. The sensitivity test of the microflora of the biomaterial, carried out by the disco-diffusion method, showed that the microorganisms of all the samples were sensitive to danofloxacin. Bacteria Streptococcus pneumonia (n = 10), Staphylococcus aureus (n = 4) and Escherichia coli (n = 2) were isolated and identified from nasal exudate samples (n = 10). Pathogenic strains of Escherichia coli were isolated from all faecal samples (n = 12). The degree of bacteriostatic activity of danofloxacin was determined by establishing its minimum inhibitory concentration (MIC) for bacterial isolates by sequential dilutions in a liquid nutrient medium. The average MIC of danofloxacin for Streptococcus pneumoniae isolates was 0.26 ± 0.13 μg/ml and for Staphylococcus aureus isolates – 0.25 ± 0.075 μg/ml. For Escherichia coli strains isolated from faeces of goats suffering from coli infection, the average MIC of danofloxacin was 0.38 ± 0.12 μg/ml (range 0.2 to 0.8 μg/ml). Antimicrobial sensitivity testing have shown a high level of bacteriostatic activity of danofloxacin against bacteria, pathogens of respiratory and intestinal infections in goats. This may be the argument for the use of danofloxacin-based chemotherapeutic agents in the treatment of bacterial infections in goats, especially for the empirical approach to therapy.

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Short Communication: Methicillin-Resistant Staphylococcus aureus Infections in Children and Young Adults Infected with HIV

AIDS Research and Human Retroviruses ◽

10.1089/aid.2009.0040 ◽

2009 ◽

Vol 25 (12) ◽

pp. 1219-1224 ◽

Cited By ~ 12

Author(s):

Ashok Srinivasan ◽

Steven Seifried ◽

Liang Zhu ◽

Wally Bitar ◽

Deo K. Srivastava ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Young Adults ◽

Methicillin Resistant Staphylococcus Aureus ◽

Short Communication ◽

Methicillin Resistant ◽

Children And Young Adults

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Resistance to the chemotherapeutic agents of Staphylococcus aureus strains isolated from hospitalized patients

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2014.03.593 ◽

2014 ◽

Vol 21 ◽

pp. 79-80 ◽

Cited By ~ 2

Author(s):

L.M. Junie ◽

L.M. Simon ◽

S.L. Pandrea

Keyword(s):

Staphylococcus Aureus ◽

Chemotherapeutic Agents ◽

Hospitalized Patients

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Adjuvant Chemotherapy in Patients with Osteosarcoma

European Oncology & Haematology ◽

10.17925/eoh.2011.07.03.183 ◽

2011 ◽

Vol 07 (03) ◽

pp. 183

Author(s):

Noah Federman ◽

William Tap ◽

◽

Keyword(s):

Young Adults ◽

Adjuvant Chemotherapy ◽

Malignant Neoplasm ◽

Chemotherapeutic Agents ◽

Term Survival ◽

Future Directions ◽

The Past ◽

Metastatic Osteosarcoma ◽

Improvement In Survival

Osteosarcoma is the most common primary malignant neoplasm of bone in children, adolescents and young adults. Prior to 1970, the outcome for patients with osteosarcoma was dismal, with only 1020 % of patients achieving long-term survival. The improvement in survival over the past four decades, now approaching 75 %, has largely been due to the addition of adjuvant chemotherapy to surgery. However, for patients that have metastatic osteosarcoma or recurrence of their cancer, the outlook is poor and the prognosis has not improved over the past several decades, despite the advent and use of newer chemotherapeutic agents and combinations. This review will focus on the current chemotherapeutic treatments of localised osteosarcoma, the controversies surrounding adjuvant therapy and future directions and additions to our armamentarium.

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Two Cases of Infectious Endocarditis Caused by Methicillin-sensitive Staphylococcus Aureus in Young Adults with Atopic Dermatitis

Nihon Naika Gakkai Zasshi ◽

10.2169/naika.101.1680 ◽

2012 ◽

Vol 101 (6) ◽

pp. 1680-1683

Author(s):

Kazushi Fukagawa ◽

Ryuichi Aikawa ◽

Kazunao Haba ◽

Nagako Kitagawa ◽

Kunihiro Higuchi ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Young Adults ◽

Atopic Dermatitis ◽

Infectious Endocarditis

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Identification of Functional Regulatory Residues of the β-Lactam Inducible Penicillin Binding Protein in Methicillin-Resistant Staphylococcus aureus

Chemotherapy Research and Practice ◽

10.1155/2013/614670 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10

Author(s):

Andreas N. Mbah ◽

Raphael D. Isokpehi

Keyword(s):

Staphylococcus Aureus ◽

Binding Site ◽

Binding Protein ◽

Clinical Problem ◽

Structural Features ◽

Chemotherapeutic Agents ◽

Penicillin Binding Protein ◽

Methicillin Resistant ◽

Regulatory Analysis ◽

New Protein

Resistance to methicillin by Staphylococcus aureus is a persistent clinical problem worldwide. A mechanism for resistance has been proposed in which methicillin resistant Staphylococcus aureus (MRSA) isolates acquired a new protein called β-lactam inducible penicillin binding protein (PBP-2′). The PBP-2′ functions by substituting other penicillin binding proteins which have been inhibited by β-lactam antibiotics. Presently, there is no structural and regulatory information on PBP-2′ protein. We conducted a complete structural and functional regulatory analysis of PBP-2′ protein. Our analysis revealed that the PBP-2′ is very stable with more hydrophilic amino acids expressing antigenic sites. PBP-2′ has three striking regulatory points constituted by first penicillin binding site at Ser25, second penicillin binding site at Ser405, and finally a single metallic ligand binding site at Glu657 which binds to Zn2+ ions. This report highlights structural features of PBP-2′ that can serve as targets for developing new chemotherapeutic agents and conducting site direct mutagenesis experiments.

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Spontaneous Deletion of the Methicillin Resistance Determinant, mecA, Partially Compensates for the Fitness Cost Associated with High-Level Vancomycin Resistance in Staphylococcus aureus

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01164-07 ◽

2008 ◽

Vol 52 (4) ◽

pp. 1221-1229 ◽

Cited By ~ 48

Author(s):

Michael J. Noto ◽

Paige M. Fox ◽

Gordon L. Archer

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistance ◽

Chemotherapeutic Agents ◽

Vancomycin Resistance ◽

Resistance Determinant ◽

Gene Acquisition ◽

Resistant Strains ◽

Vancomycin Resistant ◽

Mrsa Strains ◽

High Level

ABSTRACT Treatment of infections caused by Staphylococcus aureus is often confounded by the bacterium's ability to develop resistance to chemotherapeutic agents. Methicillin-resistant S. aureus (MRSA) arises through the acquisition of staphylococcal chromosomal cassette mec (SCCmec), a genomic island containing the methicillin resistance determinant, mecA. In contrast, resistance to vancomycin can result from exposure to the drug, a mechanism that is not dependent upon a gene acquisition event. Here we describe three MRSA strains that became resistant to vancomycin during passage in the presence of increasing concentrations of the drug. In each case two derivative strains were isolated, one that had lost mecA and one that retained mecA during passage. Strain 5836VR lost mecA by the site-specific chromosomal excision of SCCmec, while the other two strains (strains 3130VR and VP32) deleted portions of their SCCmec elements in a manner that appeared to involve IS431. Conversion to vancomycin resistance caused a decrease in the growth rate that was partially compensated for by the deletion of mecA. In mixed-culture competition experiments, vancomycin-resistant strains that lacked mecA readily outcompeted their mecA-containing counterparts, suggesting that the loss of mecA during conversion to vancomycin resistance was advantageous to the organism.

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Analysis of community- and hospital-acquired bacteraemia during a recent 5-year period

Journal of Medical Microbiology ◽

10.1099/jmm.0.069054-0 ◽

2014 ◽

Vol 63 (3) ◽

pp. 421-426 ◽

Cited By ~ 10

Author(s):

Hee-Won Moon ◽

Young Jin Ko ◽

Seungman Park ◽

Mina Hur ◽

Yeo-Min Yun

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Young Adults ◽

Klebsiella Pneumoniae ◽

E Coli ◽

Mixed Features ◽

Healthcare Associated ◽

Micro Organisms ◽

Hospital Acquired ◽

Age And Sex

There are sparse data concerning sex- and age-specific characteristics of community-acquired bacteraemia (CAB) and hospital-acquired bacteraemia (HAB). Between January 2008 and December 2012, we identified 2956 bacteraemia cases, which we classified as CAB, HAB or healthcare-associated bacteraemia (HCAB). Almost half of the pathogens were Escherichia coli in CAB patients. By contrast, Staphylococcus aureus was most frequent (16.2 %) in HAB patients. HCAB showed mixed features of CAB and HAB. In CAB, E. coli was significantly more abundant in females than in males (56.9 vs 24.3 %, respectively). This trend was most striking in young adults (20–39 years) (77.2 % in females vs 11.4 % in males). HAB cases showed greater heterogeneity in their associated pathogens. The extended-spectrum β-lactamase-positive rates of E. coli and Klebsiella pneumoniae, respectively, were 31.3 and 33.8 % in HAB and 8.8 and 8.4 % in CAB. The non-susceptibility rates of S. aureus to oxacillin were 37.4 % in CAB and 73.0 % in HAB. In conclusion, CAB and HAB showed different distributions of micro-organisms, and these distributions also differed with patient age and sex. In addition, antimicrobial susceptibility needs to be monitored separately.

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HYDRAZIDE SCHIFF BASES OF ACETYLACETONATE METAL COMPLEXES: SYNTHESIS, SPECTROSCOPIC AND BIOLOGICAL STUDIES

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i12.22225 ◽

2017 ◽

Vol 9 (12) ◽

pp. 257 ◽

Cited By ~ 3

Author(s):

Charity W. Dikio ◽

Ikechukwu P. Ejidike ◽

Fanyana M. Mtunzi ◽

Michael J. Klink ◽

Ezekiel D. Dikio

Keyword(s):

Staphylococcus Aureus ◽

Schiff Base ◽

Metal Complexes ◽

Enterococcus Faecalis ◽

Schiff Bases ◽

Condensation Reaction ◽

Chemotherapeutic Agents ◽

Schiff Base Ligands ◽

Biological Studies ◽

Ft Ir

Objective: The study was focused on the synthesis and spectroscopic studies of metal acetylacetonates and their complexes using bidentate Schiff-base ligands (NO), evaluation of their in-vitro antibacterial potentials against pathogenic microorganism.Methods: Acetylacetonate salts of Cobalt(II), Manganese(II) and Magnesium(II) were prepared by reacting their metal hydroxides with acetylacetone. The metal complexes of N'-{(E)-[4-(diethylamino)-2-hydroxyphenyl]methylidene}-4-nitrobenzohydrazide (HL1), N'-{(E)-[4-(diethylamino)-2-hydroxyphenyl]methylidene}-4-methoxybenzohydrazide (HL2) obtained from the condensation reaction of 4-(diethylamino)-2-hydroxybenzaldehyde and 4-nitrobenzohydrazide/ or 4-methoxybenzohydrazide. The synthesized compounds were characterized by fourier transform infrared spectroscopy (FT-IR), proton and carbon-13 nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA). The compounds were screened for their antimicrobial properties against a list of Gram-positive bacterial strains.Results: The FT-IR spectra revealed that the Schiff bases acts as bidentate chelating ligand via nitrogen of the azomethine and phenolic oxygen atoms. NMR reveal the presence of azomethine (HC=N) and aromatic hydrogens at expected chemical shifts confirming the formation of the Schiff base ligands. Thermal decomposition behaviour was studied by thermogravimetry revealing stability up to 260 °C. The compounds were evaluated for their antibacterial potentials against Staphylococcus aureus and Enterococcus faecalis. The manganese acetylacetonato(N'-{(E)-[4-(diethylamino)-2-hydroxyphenyl]methylidene}-4-methoxybenzohydrazide: Mn(acac)(L2) exhibited antimicrobial activities against both Enterococcus faecalis and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 398.0 μg/mL.Conclusion: The prepared compounds showed no inhibition against the selected pathogenic microorganisms except for Mn(acac)(L2) Standard antibacterial compounds: ampicillin and ciprofloxacin were used as positive control. The antibacterial activity of the compound depends on the kind of substituent on the benzo hydrazide rings at the para position, thereby suggesting the compound as promising chemotherapeutic agents for further structural optimization.

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