1
|
Gordon AT, Hosten EC, van Vuuren S, Ogunlaja AS. Copper(II)-photocatalyzed Hydrocarboxylation of Schiff bases with CO 2: antimicrobial evaluation and in silico studies of Schiff bases and unnatural α-amino acids. J Biomol Struct Dyn 2024:1-14. [PMID: 38192072 DOI: 10.1080/07391102.2024.2301765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 12/30/2023] [Indexed: 01/10/2024]
Abstract
We synthesized and characterized two copper(II) complexes: [CuL2Cl]Cl and [CuL'2Cl]Cl, where L = 2,2'-bipyridine and L' = 4,4'-dimethyl-2,2'-bipyridine. We evaluated their photocatalytic hydrocarboxylation properties on a series of synthesized Schiff bases (SBs): (E)-1-(4-((5-bromo-2-hydroxybenzylidene)amino)phenyl)ethanone (SB1), (E)-N-(4-(dimethylamino)benzylidene)benzo[d]thiazol-2-amine (SB2), (E)-4-Bromo-2-((thiazol-2-ylimino)methyl)phenol (SB3), and (E)-4-((5-bromo-2-hydroxybenzylidene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (SB4). Under mild photocatalytic reaction conditions (room temperature, 1 atm CO2, 30-watt Blue LED light), the derivatives of α-amino acids UAA1-4 were obtained with yields ranging from 5% to 44%. Experimental results demonstrated that [CuL2Cl]Cl exhibited superior photocatalytic efficiency compared to [CuL'2Cl]Cl, attributed to favourable electronic properties. In silico studies revealed strong binding strengths with E. faecalis DHFR (4M7U) for docked Schiff bases (SB) and unnatural α-amino acids (UAAs). In vitro studies further demonstrated significant antimicrobial and antifungal activity for SB2, SB3, and SB4, while none of the synthesized UAAs exhibited such properties, primarily due to the electronic and binding properties of these molecules.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Allen T Gordon
- Department of Chemistry, Nelson Mandela University, Port Elizabeth, South Africa
| | - Eric C Hosten
- Department of Chemistry, Nelson Mandela University, Port Elizabeth, South Africa
| | - Sandy van Vuuren
- Department of Pharmacy and Pharmacology, Faculty of Health Sciences, University of the Witwatersrand, Parktown, South Africa
| | - Adeniyi S Ogunlaja
- Department of Chemistry, Nelson Mandela University, Port Elizabeth, South Africa
| |
Collapse
|
2
|
El-Naggar NEA, El-Bindary AAA, Abdel-Mogib M, Nour NS. In vitro activity, extraction, separation and structure elucidation of antibiotic produced by Streptomyces anulatus NEAE-94 active against multidrug-resistant Staphylococcus aureus. BIOTECHNOL BIOTEC EQ 2017. [DOI: 10.1080/13102818.2016.1276412] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Noura El-Ahmady El-Naggar
- Department of Bioprocess Development, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, Alexandria, Egypt
| | | | - Mamdouh Abdel-Mogib
- Department of Chemistry, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Noura Salah Nour
- Department of Bioprocess Development, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, Alexandria, Egypt
| |
Collapse
|
3
|
Xu LQ, Zeng JW, Jiang CH, Wang H, Li YZ, Wen WH, Li JH, Wang F, Ting WJ, Sun ZY, Huang CY. Isolation and determination of four potential antimicrobial components from Pseudomonas aeruginosa extracts. Int J Med Sci 2017; 14:1368-1374. [PMID: 29200950 PMCID: PMC5707753 DOI: 10.7150/ijms.18896] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 10/11/2017] [Indexed: 11/25/2022] Open
Abstract
Background:Pseudomonas aeruginosa can cause disease and also can be isolated from the skin of healthy people. Additionally, it exhibits certain antimicrobial effects against other microorganisms.Methods: We collected 60 strains of P. aeruginosa and screened their antimicrobial effects against Staphylococcus aureus (ATCC 25923) using the filter paper-disk method, the cross-streaking method and the co-culture method and then evaluated the antimicrobial activity of the chloroform-isolated S. aureus extracts against methicillin-resistant S. aureus (MRSA, Gram-positive cocci), vancomycin intermediate-resistant S. aureus (VISA, Gram-positive cocci), Corynebacterium spp. (CS, Gram-positive bacilli), Acinetobacter baumannii (AB, Gram-negative bacilli), Moraxella catarrhalis (MC, Gram-negative diplococcus), Candida albicans (CA, fungi), Candida tropicalis (CT, fungi), Candida glabrata (CG, fungi) and Candida parapsilosis (CP, fungi). Results: The PA06 and PA46 strains have strong antimicrobial effects. High-performance liquid chromatography (HPLC) analysis revealed that the major components of PA06 and PA46 that exhibit antimicrobial activity are functionally similar to phenazine-1-carboxylic acid (PCA) and pyocyanin. Preparative HPLC was performed to separate and isolate the 4 major potential antimicrobial components: PA06ER10, PA06ER16, PA06ER23 and PA06ER31. Further, the molecular masses of PA06ER10 (260.1), PA06ER16 (274.1), PA06ER23 (286.1) and PA06ER31 (318.2) were determined by electrospray ionization (ESI) mass spectrometry. Conclusion:P. aeruginosa can produce small molecules with potential antimicrobial activities against MRSA, VISA, CS, MC, CA, CT, CG and CP but not against AB.
Collapse
Affiliation(s)
- Ling-Qing Xu
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Jian-Wen Zeng
- Department of Urology, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Chong-He Jiang
- Department of Urology, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Huan Wang
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Yu-Zhen Li
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Wei-Hong Wen
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Jie-Hua Li
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China
| | - Feng Wang
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| | - Wei-Jen Ting
- Department of Clinical Laboratory, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangdong, China.,Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan
| | - Zi-Yong Sun
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| | - Chih-Yang Huang
- Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan.,Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan.,Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| |
Collapse
|
4
|
Reda FM, Shafi SA, Ismail M. Efficient inhibition of some multi-drug resistant pathogenic bacteria by bioactive metabolites from Bacillus amyloliquefaciens S5I4 isolated from archaeological soil in Egypt. APPL BIOCHEM MICRO+ 2016. [DOI: 10.1134/s0003683816060144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
5
|
Xu L, Wang F, Shen Y, Hou H, Liu W, Liu C, Jian C, Wang Y, Sun M, Sun Z. Pseudomonas aeruginosa inhibits the growth of pathogenic fungi: In vitro and in vivo studies. Exp Ther Med 2014; 7:1516-1520. [PMID: 24926335 PMCID: PMC4043586 DOI: 10.3892/etm.2014.1631] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 02/27/2014] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to investigate the inhibitory effect of Pseudomonas aeruginosa (PA) on pathogenic fungi, including Candida albicans (CA), Candida tropicalis (CT), Candida glabrata (CG), Candida parapsilosis (CP) and Candida krusei (CK), in vitro and in vivo. In total, 24 PA strains were collected from clinical specimens and identified by Gram staining, oxidase production and the API 20NE system. Cross-streak, disk diffusion and co-culture methods were used to observe the inhibitory effect of PA. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to analyze differences in the bacterial proteins of PA. A blood infection model in mice was used to evaluate the effect of PA on fungi in vivo. The in vitro and in vivo results demonstrated that a number of PA isolates exhibited a marked inhibitory effect on pathogenic fungi, including CA, CT, CP, CG and CK, while other PA strains exhibited no effect. Therefore, PA exhibits an inhibitory effect on pathogenic fungi and this activity may be important in the treatment of patients. It was hypothesized that PA secretes various types of proteins to suppress the growth of fungal filaments, which subsequently inhibits pathogenic fungi.
Collapse
Affiliation(s)
- Lingqing Xu
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Feng Wang
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Yin Shen
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Hongyan Hou
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Weiyong Liu
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Cailin Liu
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Cui Jian
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Yue Wang
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Mingyue Sun
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Ziyong Sun
- Department of Clinical Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| |
Collapse
|
6
|
Yar M, Mushtaq N, Afzal S. Synthesis, reactions, applications, and biological activity of diethanolamine and its derivatives. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2013. [DOI: 10.1134/s1070428013070014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
7
|
Konaté K, Zerbo P, Ouédraogo M, Dibala CI, Adama H, Sytar O, Brestic M, Barro N. Anti-nociceptive properties in rodents and the possibility of using polyphenol-rich fractions from sida urens L. (Malvaceae) against of dental caries bacteria. Ann Clin Microbiol Antimicrob 2013; 12:14. [PMID: 23787152 PMCID: PMC3699430 DOI: 10.1186/1476-0711-12-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 06/08/2013] [Indexed: 11/17/2022] Open
Abstract
Background Sida urens L. (Malvaceae) is in flora of Asian medicinal herbs and used traditionally in West of Burkina Faso for the treatment of infectious diseases and particularly used against, dental caries bacteria, fever, pain and possesses analgesic properties. This study was conducted to reveal the antibacterial effect against dental caries bacteria on the one hand, and evaluate their analgesic capacity in experimental model with Swiss mice and on the other hand, with an aim to provide a scientific basis for the traditional use of this plant for the management of dental caries bacteria. Method The antibacterial assays in this study were performed by using inhibition zone diameters, MIC (Minimum inhibitory concentration) and MBC (Minimal bactericidal concentration) methods. On the whole the dental caries bacteria (Gram-positive and Gram-negative bacterial strains) were used. Negative control was prepared using discs impregnated with 10% DMSO in water and commercially available Gentamicin from Alkom Laboratories LTD was used as positive reference standards for all bacterial strains. In acute toxicity test, mice received doses of extract (acetone/water extract) from Sida urens L. by intraperitoneal route and LD50 was determined in Swiss mice. As for analgesic effects, acetic acid writhing method was used in mice. The acetic acid-induced writhing method was used in mice with aim to study analgesic effects. Results The results showed that the highest antibacterial activities were founded with the polyphenol-rich fractions against all bacterial strains compared to the standard antibiotic. About preliminary study in acute toxicity test, LD50 value obtained was more than 5000 mg/kg b.w. Polyphenol-rich fractions produced significant analgesic effects in acetic acid-induced writhing method and in a dose-dependent inhibition was observed. Conclusion These results validate the ethno-botanical use of Sida urens L. (Malvaceae) and demonstrate the potential of this herbaceous as a potential antibacterial agent of dental caries that could be effectively used for future health care purposes.
Collapse
|
8
|
Fawad SA, Khalid N, Asghar W, Suleria HAR. In vitro comparative study of Bougainvillea spectabilis “stand” leaves and Bougainvillea variegata leaves in terms of phytochemicals and antimicrobial activity. Chin J Nat Med 2012. [DOI: 10.1016/s1875-5364(12)60085-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
9
|
Tawiah AA, Gbedema SY, Adu F, Boamah VE, Annan K. Antibiotic producing microorganisms from River Wiwi, Lake Bosomtwe and the Gulf of Guinea at Doakor Sea Beach, Ghana. BMC Microbiol 2012; 12:234. [PMID: 23072432 PMCID: PMC3493300 DOI: 10.1186/1471-2180-12-234] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 09/27/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Microorganisms have provided a wealth of metabolites with interesting activities such as antimicrobial, antiviral and anticancer. In this study, a total of 119 aquatic microbial isolates from 30 samples (taken from water bodies in Ghana) were screened by the agar-well diffusion method for ability to produce antibacterial-metabolites. RESULTS Antibacterial activity was exhibited by 27 of the isolates (14 bacteria, 9 actinomycetes and 4 fungi) against at least one of the indicator microorganisms: Enterococcus faecalis (ATCC 29212), Bacillus thuringiensis (ATCC 13838), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Proteus vulgaris (NCTC 4635) and Bacillus Subtilis (NCTC 10073). A sea isolate MAI2 (identified as a strain of Pseudomonas aeruginosa) exhibited the highest antibacterial activity (lowest zone of inhibition = 22 mm). The metabolites of MAI2 extracted with chloroform were stable to heat and gave minimum inhibitory concentrations ranging between 250 and 2000 μg/ml. Bioautography of the extract revealed seven active components. CONCLUSION This study has therefore uncovered the potential of water bodies in the West African sub-region as reservoirs of potent bioactive metabolite producing microorganisms.
Collapse
Affiliation(s)
- Adelaide A Tawiah
- Department of Pharmaceutics, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and technology, Kumasi, Ghana
| | - Stephen Y Gbedema
- Department of Pharmaceutics, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and technology, Kumasi, Ghana
| | - Francis Adu
- Department of Pharmaceutics, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and technology, Kumasi, Ghana
| | - Vivian E Boamah
- Department of Pharmaceutics, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and technology, Kumasi, Ghana
| | - Kofi Annan
- Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and technology, Kumasi, Ghana
| |
Collapse
|
10
|
Rodrigues FFG, Oliveira LGS, Rodrigues FFG, Saraiva ME, Almeida SCX, Cabral MES, Campos AR, Costa JGM. Chemical composition, antibacterial and antifungal activities of essential oil from Cordia verbenacea DC leaves. Pharmacognosy Res 2012; 4:161-5. [PMID: 22923954 PMCID: PMC3424843 DOI: 10.4103/0974-8490.99080] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Revised: 12/03/2011] [Accepted: 07/27/2012] [Indexed: 12/03/2022] Open
Abstract
Background: Cordia verbenacea is a Brazilian coastal shrub popularly known as “erva baleeira”. The essential oil from fresh leaves was obtained by hydrodistillation and analyzed by CG/MS. The main components were identified as β-caryophyllene (25.4%), bicyclogermacrene (11.3%), δ-cadinene (9.%) and α-pinene (9.5%). In this study, the antimicrobial activity of Cordia verbenacea was evaluated. Materials and Methods: The minimal inhibitory concentration (MIC) of the essential oil was obtained using the broth microdilution assay (from 512 to 8 μg/ml). Results: The results showed that the essential oil presented fungistatic activity against Candida albicans and Candida krusei and antibacterial activity against Gram-positive strains (Staphylococcus aureus and Bacillus cereus) and against multiresistant Gram-negative (Escherichia coli 27), in all tests the MIC was 64 μg/ml. When the essential oil was associated to aminoglycosides (subinhibitory concentrations, MIC/8), a synergic and antagonic activity was verified. The synergic effect was observed to the amikacin association (MIC reduction from 256 mlto 64 μg/ml) in all strains tested. Conclusion: The essential oil of Cordia verbenacea influences the activity of antibiotics and may be used as an adjuvant in antibiotic therapy against respiratory tract bacterial pathogens.
Collapse
Affiliation(s)
- Fabiola F G Rodrigues
- Department of Biological Chemistry, Molecular Bioprospection Post-graduation Program, Laboratory of Natural Products Research, Regional University of Cariri, Crato, CE, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Lazreg-Aref H, Mars M, Fekih A, Aouni M, Said K. Chemical composition and antibacterial activity of a hexane extract of Tunisian caprifig latex from the unripe fruit of Ficus carica. PHARMACEUTICAL BIOLOGY 2012; 50:407-412. [PMID: 22136172 DOI: 10.3109/13880209.2011.608192] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
CONTEXT The plant kingdom has become a target in the search for new drugs and biologically active lead compounds. The common Jrani Tunisian caprifig Ficus carica L. (Moraceae) is one of the large number of plant species that are used in folklore medicine yet to be investigated for the treatment of many diseases, including those of infectious nature. OBJECTIVE Hexane extract of the Tunisian common Jrani caprifig latex was assayed for antibacterial activity against several Gram-positive and Gram-negative bacteria. Chemical composition of the extract was also investigated. MATERIALS AND METHODS The hexane extract was obtained from Tunisian Jrani caprifig latex by maceration, and then analyzed by gas chromatography-mass spectrometry. The extract was tested in vitro for antibacterial activity by the disc diffusion method and minimal inhibitory concentration (MIC) was also determined for all the test cultures. RESULTS Thirty-six compounds of the extract were identified, 90.56% of the total area of peaks were coumarins. A strong bactericidal effect was demonstrated. The most sensitive bacteria were Staphylococcus saprophyticus clinical isolate, and Staphylococcus aureus ATCC 25923, with a MIC of 19 µg/mL. DISCUSSION AND CONCLUSION These findings demonstrate an effective in vitro antibacterial activity of the hexane extract of caprifig latex.
Collapse
Affiliation(s)
- Houda Lazreg-Aref
- Laboratoire de Génétique, Biodiversité et Valorisation des Bio ressources (UR 03ES09), Institut Supérieur de Biotechnologie, Monastir, Tunisie.
| | | | | | | | | |
Collapse
|
12
|
Prakash NU, Bhuvaneswa S, Jahnavi B, Abhinaya K, Rajalin AG, Kumar MP, Sundrarama G, Elumalai K, Devipriya S, Kannan V, Sriraman V, Kathiravan G. A Study on Antibacterial Activity of Common Weeds in Northern Districts of Tamil Nadu, India. ACTA ACUST UNITED AC 2012. [DOI: 10.3923/rjmp.2012.341.345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
13
|
Cock IE, Kalt FR. Toxicity evaluation of Xanthorrhoea johnsonii leaf methanolic extract using the Artemia franciscana bioassay. Pharmacogn Mag 2011; 6:166-71. [PMID: 20931073 PMCID: PMC2950376 DOI: 10.4103/0973-1296.66929] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 02/05/2010] [Accepted: 07/30/2010] [Indexed: 11/23/2022] Open
Abstract
The toxicity of Xanthorrhoea johnsonii methanolic leaf extract was investigated using the Artemia franciscana nauplii bioassay. At 24 h, the extract produced an EC50 of 361.0 ± 41.8 μg/ml, indicating that it was substantially more toxic than the pesticide Mevinphos (1346.2 ± 80.1 μg/ml) and approximately 4 fold less toxic than potassium dichromate (87.1 ± 5.2 μg/ml). Whilst potassium dichromate LC50 values remained constant across the 72-h test period, these values decreased for the extract and Mevinphos to similar values (199.8 ± 60.5 and 114 ± 12.8 μg/ml, respectively), indicating their similar level of efficacy. Noteworthy was the apparent anesthetic effect of X. johnsonii leaf extract. Although the extract initially appeared to kill the A. franciscana nauplii, they were seen to temporarily recover by 48 h only to die by 72 h.
Collapse
Affiliation(s)
- I E Cock
- Biomolecular and Physical Sciences, Nathan Campus, Griffith University 170 Kessels Road, Nathan, Queensland 4111 Australia
| | | |
Collapse
|
14
|
Brown J, Aitken SL, van Manen RP. Potential for Linezolid-Related Blindness: A Review of Spontaneous Adverse Event Reports. Pharmacotherapy 2011; 31:585-90. [DOI: 10.1592/phco.31.6.585] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
15
|
Moschovi M, Trimis G, Tsotra M, Chatzi F, Karamolegou K, Santou A, Tourkantoni N, Chrousos G. Efficacy and safety of linezolid in immunocompromised children with cancer. Pediatr Int 2010; 52:694-8. [PMID: 20149126 DOI: 10.1111/j.1442-200x.2010.03097.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The aim of this study was to determine the safety, tolerance and efficacy of linezolid for the treatment of infections from Gram-positive bacteria in immunocompromised children with cancer. METHODS This was a prospective non-comparative unblinded study in the Hematology/Oncology Unit over a two-year period, administering linezolid as monotherapy in children with cancer. RESULTS Seventeen children received linezolid (30 mg/kgr: 3 i.v. per day). Mean duration of linezolid administration was 12.2 days (range, 6-38 days), while the median age of the evaluable patients was 2.2 years (range, 6 months-11.2 years). Primary diagnosis was acute lymphoblastic leukemia (nine patients), brain tumor (three patients), multi-organ Langerhans cell histiocytosis (two patients), rhabdomyosarcoma, Burkitt's lymphoma and ovarian tumor (one patient each). All patients were in the midst of chemotherapy cycles. Ten out of 17 children had positive blood cultures (methicillin-resistant Staphylococcus aureus, four patients; vancomycin-resistant Enterococcus, three patients; penicillin-resistant Streptococcus pneumoniae, three patients), while seven of the 17 had fever and vancomycin-resistant Enterococcus in stool cultures. All patients were considered clinically cured after the end of the linezolid regimen (100% efficacy). The main adverse events were thrombocytopenia grade 1-3 and anemia grade 2-3 (four and two patients, respectively). Chemotherapy-induced myelotoxicity (six patients) was not worsened during linezolid therapy. No bleeding episodes were presented. Self-limited diarrhea grade 1-2 was presented in four patients (mean duration 2 days). The total adverse event rate was 23.5%; however, there was no premature cessation of linezolid in any patient. CONCLUSIONS Linezolid may be another effective and safe therapy to treat infections from resistant Gram-positive bacteria in immunocompromised children, even in young ages.
Collapse
Affiliation(s)
- Maria Moschovi
- First Department of Paediatrics, Athens University Medical School, Aghia Sophia Children's Hospital, Athens, Greece
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Zhanel GG, Calic D, Schweizer F, Zelenitsky S, Adam H, Lagacé-Wiens PR, Rubinstein E, Gin AS, Hoban DJ, Karlowsky JA. New Lipoglycopeptides. Drugs 2010; 70:859-86. [DOI: 10.2165/11534440-000000000-00000] [Citation(s) in RCA: 234] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
|
17
|
Rao K, Ch B, Narasu LM, Giri A. Antibacterial activity of Alpinia galanga (L) Willd crude extracts. Appl Biochem Biotechnol 2010; 162:871-84. [PMID: 20387130 DOI: 10.1007/s12010-009-8900-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Accepted: 12/28/2009] [Indexed: 11/26/2022]
Abstract
Methanol, acetone and diethyl ether extracts of Alpinia galanga have been evaluated against pathogens viz. Bacillus subtilis MTCC 2391, Enterobacter aerogene, Enterobacter cloacae, Enterococcus faecalis, Escherichia coli MTCC 1563, Klebsiella pneumoniae, Pseudomonas aeruginosa MTCC 6642, Salmonella typhimurium, Staphylococcus aureus and Streptococcus epidermis using Agar well diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of all the extracts were determined using the macrodilution method. Methanol extracts have shown excellent activity towards all the pathogens with MIC and MBC values ranging from 0.04-1.28 mg/ml and 0.08-2.56 mg/ml, respectively. The GC-MS analysis of methanol extracts have yielded compounds like 5-hydroxymethyl furfural (59.9%), benzyl alcohol (57.6%), 1,8 cineole (15.65%), methylcinnamate (9.4%), 3-phenyl-2-butanone (8.5%) and 1,2 benzenedicarboxylic acid (8.9%), which could be responsible for its broad spectrum activity. So, A. galanga can be quite resourceful for the development of new generation drugs.
Collapse
Affiliation(s)
- Kiranmayee Rao
- Centre for Biotechnology, Institute of Science and Technology, Jawaharlal Nehru Technological University Hyderabad, Kukatpally, Hyderabad 500 085, India
| | | | | | | |
Collapse
|
18
|
Fàbrega A, Madurga S, Giralt E, Vila J. Mechanism of action of and resistance to quinolones. Microb Biotechnol 2009; 2:40-61. [PMID: 21261881 PMCID: PMC3815421 DOI: 10.1111/j.1751-7915.2008.00063.x] [Citation(s) in RCA: 257] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 08/20/2008] [Accepted: 08/24/2008] [Indexed: 01/11/2023] Open
Abstract
Fluoroquinolones are an important class of wide-spectrum antibacterial agents. The first quinolone described was nalidixic acid, which showed a narrow spectrum of activity. The evolution of quinolones to more potent molecules was based on changes at positions 1, 6, 7 and 8 of the chemical structure of nalidixic acid. Quinolones inhibit DNA gyrase and topoisomerase IV activities, two enzymes essential for bacteria viability. The acquisition of quinolone resistance is frequently related to (i) chromosomal mutations such as those in the genes encoding the A and B subunits of the protein targets (gyrA, gyrB, parC and parE), or mutations causing reduced drug accumulation, either by a decreased uptake or by an increased efflux, and (ii) quinolone resistance genes associated with plasmids have been also described, i.e. the qnr gene that encodes a pentapeptide, which blocks the action of quinolones on the DNA gyrase and topoisomerase IV; the aac(6')-Ib-cr gene that encodes an acetylase that modifies the amino group of the piperazin ring of the fluoroquinolones and efflux pump encoded by the qepA gene that decreases intracellular drug levels. These plasmid-mediated mechanisms of resistance confer low levels of resistance but provide a favourable background in which selection of additional chromosomally encoded quinolone resistance mechanisms can occur.
Collapse
Affiliation(s)
- Anna Fàbrega
- Department of Microbiology, Hospital Clinic, School of Medicine, University of Barcelona, Spain
| | - Sergi Madurga
- Institute for Research in Biomedicine, Barcelona, Spain
- Departments of Physical Chemistry & IQTCUB and
| | - Ernest Giralt
- Institute for Research in Biomedicine, Barcelona, Spain
- Organic Chemistry, University of Barcelona, Spain
| | - Jordi Vila
- Department of Microbiology, Hospital Clinic, School of Medicine, University of Barcelona, Spain
| |
Collapse
|
19
|
Tanaka JCA, Silva CCD, Oliveira AJBD, Nakamura CV, Dias Filho BP. Antibacterial activity of indole alkaloids from Aspidosperma ramiflorum. Braz J Med Biol Res 2006; 39:387-91. [PMID: 16501818 DOI: 10.1590/s0100-879x2006000300009] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V) obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC) was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7) CFU/mL). Microtiter plates were incubated at 37 masculineC and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 microg/mL) and S. aureus (MIC = 500 microg/mL), and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 microg/mL). Fractions I and II were inactive against standard strains at concentrations of < or =1000 microg/mL and fraction III displayed moderate antibacterial activity against B. subtilis (MIC = 500 microg/mL) and S. aureus (MIC = 250 microg/mL). Fraction IV showed high activity against B. subtilis and S. aureus (MIC = 15.6 microg/mL) and moderate activity against E. coli and P. aeruginosa (MIC = 250 microg/mL). Fraction V presented high activity against B. subtilis (MIC = 15.6 microg/mL) and S. aureus (MIC = 31.3 microg/mL) and was inactive against Gram-negative bacteria (MIC > 1000 microg/mL). Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 microg/mL) and E. faecalis (MIC = 50 microg/mL), with EC50 of 8 and 2.5 microg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.
Collapse
Affiliation(s)
- J C A Tanaka
- Departamento de Química, Universidade Estadual de Maringá, Maringá, PR, Brazil
| | | | | | | | | |
Collapse
|
20
|
Cianchetta G, Mannhold R, Cruciani G, Baroni M, Cecchetti V. Chemometric Studies on the Bactericidal Activity of Quinolones via an Extended VolSurf Approach. J Med Chem 2004; 47:3193-201. [PMID: 15163198 DOI: 10.1021/jm030986y] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An extended VolSurf approach, that additionally includes SHAPE descriptors, was applied to a dataset of 55 quinolones. Bactericidal activity was measured at Bayer AG, Germany, for Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis). Chemometric analysis was first approached via a classical VolSurf approach. The following descriptors were found most important: bactericidal activity particularly increases with high values of the best volume (BV11(OH2)) and the minimum energy (Emin1(OH2)) of the water probe, high values of the integy moment (ID(DRY)) of the lipophilic probe, and high values of the hydrophilic region (W(O)) of the hydrogen bond acceptor probe. Best volume (BV31(OH2)) of the water probe and best volume (BV12(DRY)) and lipophilic regions (D(DRY)) of the lipophilic probe as well as H-bonding capacity derived with the CO probe (HB(O)) are inversely related to activity. PLS analysis yields a five-component model with an r(2) of 0.83 and a q(2) of 0.43 after variable selection via fractional factorial design (FFD). Chemometric modeling could be improved by including newly derived SHAPE descriptors, which were merged with the VolSurf descriptors and subjected to PLS analysis. The global model of this extended VolSurf approach is optimal with two components and exhibits a significantly improved statistical quality; a marginally reduced r(2) (0.75 versus 0.83) is more than compensated by a highly improved predictivity with a q(2) of 0.63 versus 0.43. To prove model quality, external prediction of seven test set quinolones was performed. The precise prediction of all test set molecules nicely demonstrates the robustness and statistical significance of the obtained chemometric model using the extended VolSurf approach.
Collapse
Affiliation(s)
- Giovanni Cianchetta
- Dipartimento di Chimica e Tecnologia del Farmaco, Università di Perugia, Via del Liceo 1, I-06123 Perugia, Italy
| | | | | | | | | |
Collapse
|
21
|
Lowy FD, Waldhausen JA, Miller M, Sopko G, Rosenberg Y, Skarlatos SI. Report of the National Heart, Lung and Blood Institute-National Institute of Allergy and Infectious Diseases working group on antimicrobial strategies and cardiothoracic surgery. Am Heart J 2004; 147:575-81. [PMID: 15077070 DOI: 10.1016/j.ahj.2003.08.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Infections related to cardiac surgery increase morbidity and mortality, and increase cost and use of health resources. With the widespread use of synthetic materials, whether in prosthetic valves or vascular conduits, bacterial infection and, more rarely, fungal complications can be devastating, requiring prolonged antimicrobial therapy and, at times, re-operations with high morbidity and mortality rates. With the US population aging and living longer, cardiac surgery is applied to an older population with significant comorbidities, making the threat from infectious complications significant. The dwindling armamentarium of existing antimicrobial agents, a limited pharmaceutical pipeline of future therapies, and the emergence of antimicrobial-resistant bacteria have increased the challenge of treating cardiothoracic infections. Thus, there is critical need for addressing the existing and emerging issues in this area to develop new safe and effective strategies to address the clinical challenges facing cardiothoracic surgeons. As a result of this need, the National Heart, Lung, and Blood Institute and the National Institute of Allergy and Infectious Diseases convened a Working Group on April 4 and 5, 2002, in Bethesda, Md, which explored both basic science and clinical research opportunities in the prevention and treatment of major infections after cardiac surgery. Because of its importance as the most common pathogen in this setting, the focus of discussions was on the prevention and treatment of Staphylococcus aureus infections. This report summarizes the 5 main areas that the Working Group targeted (epidemiology of infections, molecular mechanisms of infections and complications, current pharmacotherapy, new frontiers, and clinical trial design) and highlights the recommendations that were set forth by the Working Group.
Collapse
Affiliation(s)
- Franklin D Lowy
- College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | | | | | | | | | | |
Collapse
|
22
|
Entenza JM, Vouillamoz J, Glauser MP, Moreillon P. Efficacy of garenoxacin in treatment of experimental endocarditis due to Staphylococcus aureus or viridans group streptococci. Antimicrob Agents Chemother 2004; 48:86-92. [PMID: 14693523 PMCID: PMC310157 DOI: 10.1128/aac.48.1.86-92.2004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The activity of garenoxacin was investigated in rats with experimental endocarditis due to staphylococci and viridans group streptococci (VGS). The staphylococci tested comprised one ciprofloxacin-susceptible and methicillin-susceptible Staphylococcus aureus (MSSA) isolate (isolate 1112), one ciprofloxacin-susceptible but methicillin-resistant S. aureus (MRSA) isolate (isolate P8), and one ciprofloxacin-resistant mutant (grlA) of P8 (isolate P8-4). The VGS tested comprised one penicillin-susceptible isolate and one penicillin-resistant isolate (Streptococcus oralis 226 and Streptococcus mitis 531, respectively). To simulate the kinetics of drugs in humans, rats were infused intravenously with garenoxacin every 24 h (peak and trough levels in serum, 6.1 and 1.0 mg/liter, respectively; area under the concentration-time curve [AUC], 63.4 mg. h/liter) or levofloxacin every 12 h (peak and trough levels in serum, 7.3 and 1.5 mg/liter, respectively; AUC, 55.6 mg. h/liter) for 3 or 5 days. Flucloxacillin, vancomycin, and ceftriaxone were used as control drugs. Garenoxacin, levofloxacin, flucloxacillin, and vancomycin sterilized >/=70% of the vegetations infected with both ciprofloxacin-susceptible staphylococcal isolates (P < 0.05 versus the results for the controls). Garenoxacin and vancomycin also sterilized 70% of the vegetations infected with ciprofloxacin-resistant MRSA isolate P8-4, whereas treatment with levofloxacin failed against this organism (cure rate, 0%; P < 0.05 versus the results obtained with the comparator drugs). Garenoxacin did not select for resistant derivatives in vivo. In contrast, levofloxacin selected for resistant variants in four of six rats infected with MRSA isolate P8-4. Garenoxacin sterilized 90% of the vegetations infected with both penicillin-susceptible and penicillin-resistant isolates of VGS. Levofloxacin sterilized only 22 and 40% of the vegetations infected with penicillin-susceptible S. oralis 226 and penicillin-resistant S. mitis 531, respectively. Ceftriaxone sterilized only 40% of those infected with penicillin-resistant S. mitis 531 (P < 0.05 versus the results obtained with garenoxacin). No quinolone-resistant VGS were detected. In all the experiments successful quinolone treatment was predicted by specific pharmacodynamic criteria (D. R. Andes and W. A. Craig, Clin. Infect. Dis. 27:47-50, 1998). The fact that the activity of garenoxacin was equal or superior to those of the standard comparators against staphylococci and VGS indicates that it is a potential alternative for the treatment of infections caused by such bacteria.
Collapse
Affiliation(s)
- José M Entenza
- Institute of Fundamental Microbiology, UNIL, Dorigny, 1015 Lausanne, Switzerland.
| | | | | | | |
Collapse
|
23
|
Affiliation(s)
- Kamal M F Itani
- Michael E. DeBakey Department of Surgery, Baylor College of Medicine and Houston Veterans Administration Medical Center (112A), 2002 Holcombe Boulevard, Houston, Texas 77030, USA.
| |
Collapse
|
24
|
Critchley IA, Blosser-Middleton RS, Jones ME, Thornsberry C, Sahm DF, Karlowsky JA. Baseline study to determine in vitro activities of daptomycin against gram-positive pathogens isolated in the United States in 2000-2001. Antimicrob Agents Chemother 2003; 47:1689-93. [PMID: 12709341 PMCID: PMC153318 DOI: 10.1128/aac.47.5.1689-1693.2003] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The activity of daptomycin was assessed by using 6,973 gram-positive bacteria isolated at 50 United States hospitals in 2000 and 2001. Among the isolates of Streptococcus pneumoniae (n = 1,163) collected, the rate of penicillin resistance was 16.1%; rates of oxacillin resistance among Staphylococcus aureus isolates (n = 1,018) and vancomycin resistance among Enterococcus faecium isolates (n = 368) were 30.0 and 59.5%, respectively. Multidrug-resistant (MDR) phenotypes (isolates resistant to three or more different chemical classes of antimicrobial agents) accounted for 14.2% of S. pneumoniae isolates, 27.1% of S. aureus isolates, and 58.4% of E. faecium isolates. For all gram-positive species tested, MICs at which 90% of the isolates tested were inhibited (MIC(90)s) and MIC ranges for directed-spectrum agents (daptomycin, quinupristin-dalfopristin, and linezolid) were identical or highly similar for isolates susceptible or resistant to other agents or MDR. Daptomycin had a MIC(90) of 0.12 micro g/ml for both penicillin-susceptible and -resistant isolates of S. pneumoniae. Against oxacillin-resistant S. aureus daptomycin had a MIC(90) of 0.5 micro g/ml, and it had a MIC(90) of 4 micro g/ml against both vancomycin-susceptible and -resistant E. faecium. The MIC(90)s for daptomycin and other directed-spectrum agents were unaffected by the regional or anatomical origin of isolates or patient demographic parameters (patient age, gender, and inpatient or outpatient care). Our results confirm the gram-positive spectrum of activity of daptomycin and that its activity is independent of susceptibility or resistance to commonly prescribed and tested antimicrobial agents. This study may serve as a baseline to monitor future changes in the susceptibility of gram-positive species to daptomycin following its introduction into clinical use.
Collapse
|
25
|
Smith PF, Birmingham MC, Noskin GA, Meagher AK, Forrest A, Rayner CR, Schentag JJ. Safety, efficacy and pharmacokinetics of linezolid for treatment of resistant Gram-positive infections in cancer patients with neutropenia. Ann Oncol 2003; 14:795-801. [PMID: 12702536 DOI: 10.1093/annonc/mdg211] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Linezolid is a recently approved oxazalidinone with extended activity against Gram-positive bacteria. We evaluated the results of linezolid therapy in neutropenic cancer patients with Gram-positive bacterial infections from a compassionate-use program. PATIENTS AND METHODS This was a prospective, multicenter, open-label, non-comparative, non-randomized compassionate-use treatment program in patients with serious Gram-positive infections. To qualify for enrollment patients were required to have an infection resistant to available antimicrobial agents, or in whom available agents had failed or to which they were intolerant. Patients with absolute neutrophil counts (ANC) <500 cells/mm(3) or <1000 cells/mm(3) and expected to decrease to <500 cells/mm(3), and who received linezolid 600 mg twice daily were included. Plasma samples for population pharmacokinetic analysis were collected. Clinical and microbiological assessments of outcomes were made at the end of therapy and at short-term follow-up. RESULTS Of the patients in the compassionate-use trial, 103 were neutropenic. The mean [standard deviation (SD)] age was 50.1 (17.5) years, 47% were female, and 47.6% had a baseline ANC </=100 cells/mm(3). The mean (SD) duration of linezolid therapy was 14.6 (11.4) days. The most common site of infection was the bloodstream (90.3%), and the most commonly identified pathogen was vancomycin-resistant Enterococcus faecium (83%). A total of 83 (80.5%) and 52 (50.4%) patients were evaluable for clinical and microbiological outcomes at the end of therapy, respectively. Clinical and microbiological cure rates in the evaluable patients were 79% and 86%, respectively. Linezolid was well-tolerated in this patient population, with an overall adverse event rate of 17.5%; 5% of patients required discontinuation of the drug due to side-effects. The pharmacokinetics of linezolid in patients with neutropenia did not differ from the overall compassionate-use population. CONCLUSIONS Linezolid was safe and effective in treating resistant Gram-positive infections in neutropenic cancer patients. Comparative clinical trials to evaluate further the effectiveness and safety of linezolid in this patient population are warranted.
Collapse
Affiliation(s)
- P F Smith
- Roswell Park Cancer Institute, Buffalo, NY 14263, USA.
| | | | | | | | | | | | | |
Collapse
|
26
|
Riffel A, Medina LF, Stefani V, Santos RC, Bizani D, Brandelli A. In vitro antimicrobial activity of a new series of 1,4-naphthoquinones. Braz J Med Biol Res 2002; 35:811-8. [PMID: 12131921 DOI: 10.1590/s0100-879x2002000700008] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The antibacterial activity of a series of 1,4-naphthoquinones was demonstrated. Disk diffusion tests were carried out against several Gram-positive and Gram-negative bacteria. The compound 5-amino-8-hydroxy-1,4-naphthoquinone was the most effective, presenting inhibition zones measuring 20 mm against staphylococci, streptococci and bacilli at 50 microg/ml. Methicillin-resistant Staphylococcus aureus and several clinical isolates of this bacterium were also inhibited. Naphthazarin, 5-acetamido-8-hydroxy-1,4-naphthoquinone, and 2,3-diamino-1,4-naphthoquinone were the next most active compounds. The minimal inhibitory concentration of the active compounds was determined against S. aureus, ranging from 30 to 125 microg/ml. All compounds presented a minimal bactericidal concentration higher than 500 microg/ml, indicating that their effect was bacteriostatic. The EC50, defined as the drug concentration that produces 50% of maximal effect, was 8 microg/ml for 5-amino-8-hydroxy-1,4-naphthoquinone against S. aureus, S. intermedius, and S. epidermidis. These results indicate an effective in vitro activity of 5-amino-8-hydroxy-1,4-naphthoquinone and encourage further studies for its application in antibiotic therapy.
Collapse
Affiliation(s)
- A Riffel
- Departamento de Ciências dos Alimentos, Instituto de Ciências e Tecnologia de Alimentos, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brasil
| | | | | | | | | | | |
Collapse
|
27
|
Chopra I, Hesse L, O'Neill A. Exploiting current understanding of antibiotic action for discovery of new drugs. J Appl Microbiol 2002. [DOI: 10.1046/j.1365-2672.92.5s1.13.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
28
|
Palombo EA, Semple SJ. Antibacterial activity of traditional Australian medicinal plants. JOURNAL OF ETHNOPHARMACOLOGY 2001; 77:151-7. [PMID: 11535358 DOI: 10.1016/s0378-8741(01)00290-2] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Fifty-six ethanolic extracts of various parts of 39 plants used in traditional Australian Aboriginal medicine were investigated for their antibacterial activities against four Gram-positive (Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus and Streptococcus pyogenes) and four Gram-negative (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella typhimurium) bacterial species. In a plate-hole diffusion assay, 12 extracts inhibited the growth of one or more of the bacteria, with five extracts showing broad spectrum antibacterial activity against Gram-positive bacteria. B. cereus was the most susceptible bacterium, with all 12 extracts displaying activity against this organism. Extracts from the leaves of Eremophila species (Myoporaceae) were the most active, with Eremophila duttonii exhibiting the greatest activity (against Gram-positive bacteria). The antibacterial effects of E. duttonii were further investigated by time-course growth assays which showed that significant growth inhibition was observed in cultures incubated in the presence of the extract within 1 h for B. cereus, E. faecalis and S. aureus and 2 h for S. pyogenes.
Collapse
Affiliation(s)
- E A Palombo
- School of Engineering and Science, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria 3122, Australia.
| | | |
Collapse
|