The Experts below are selected from a list of 3075 Experts worldwide ranked by ideXlab platform
Thomas V Riley - One of the best experts on this subject based on the ideXlab platform.
-
effect of habituation to Tea Tree melaleuca alternifolia Oil on the subsequent susceptibility of staphylococcus spp to antimicrobials triclosan Tea Tree Oil terpinen 4 ol and carvacrol
International Journal of Antimicrobial Agents, 2013Co-Authors: Natalie A Thomsen, Thomas V Riley, Katherine A Hammer, Alex Van Belkum, Christine F CarsonAbstract:The aim of this study was to seek additional data on the antimicrobial susceptibility of Staphylococcus spp. after habituation to low levels of the topical antimicrobial agent Tea Tree (Melaleuca alternifolia) Oil. Meticillin-susceptible Staphylococcus aureus (MSSA), meticillin-resistant S. aureus (MRSA) and coagulase-negative staphylococci (CoNS) were habituated to 0.075% Tea Tree Oil for 3 days. Subsequently, the susceptibility of five isolates each of MSSA, MRSA and CoNS to fusidic acid, mupirocin, chloramphenicol, linezolid and vancomycin was determined by Etest, and susceptibility to Tea Tree Oil, terpinen-4-ol, carvacrol and triclosan was determined by agar dilution. Following habituation to 0.075% Tea Tree Oil, antimicrobial MICs differed between control and habituated isolates on 33 occasions (out of a possible 150), with MICs being higher in habituated isolates on 22 occasions. Using clinical breakpoint criteria, one MSSA isolate changed susceptibility category from vancomycin-susceptible (MIC=2 μg/mL) to intermediate susceptibility (MIC=3 μg/mL) after habituation in one of two replicates. For the non-antibiotic antimicrobial agents, MICs of habituated and control isolates differed on 12 occasions (out of a possible 120); 10 occasions in MRSA and 2 occasions in MSSA. MICs were higher for habituated isolates on five occasions. However, all the differences were one serial dilution only and were not regarded as significant. Habituation to sublethal concentrations of Tea Tree Oil led to minor changes in MICs of antimicrobial agents, only one of which may have been clinically relevant. There is no evidence to suggest that Tea Tree Oil induces resistance to antimicrobial agents.
-
use of deception to achieve double blinding in a clinical trial of melaleuca alternifolia Tea Tree Oil for the treatment of recurrent herpes labialis
Contemporary Clinical Trials, 2008Co-Authors: Christine F Carson, David Smith, Gail J Lampacher, Thomas V RileyAbstract:Double-blinding is an important and widely implemented feature of clinical trials although its success is rarely assessed. In a randomized, placebo-controlled trial of Tea Tree Oil, an aromatic essential Oil, for the treatment of recurrent herpes labialis (RHL), or cold sores, deception was used to prevent volunteers from identifying their treatment allocation. Volunteers received placebo (n = 102) or Tea Tree Oil (n = 112) ointment in preparation for their next episode of RHL and were told, falsely, that the aroma of the ointments had been changed to prevent identification of the treatment group. At the trial's end, of the volunteers who had used their ointment and presented for treatment assessment (n = 100), approximately 50% correctly guessed their treatment allocation (P = 0.774). Amongst volunteers that had not presented for treatment assessment (n = 114), 12 volunteers did not provide blinding data and 46 did not open their tube. For the 56 volunteers who opened their tube, less than half of those receiving Tea Tree Oil (44.4%) and only a small proportion of those on placebo (17.2%) were able to correctly identify their treatment allocation. Among the volunteers that were not treated, the P-value was 0.083. This study showed that the ethical use of deception may provide effective blinding in challenging circumstances.
-
in vitro susceptibility of madurella mycetomatis prime agent of madura foot to Tea Tree Oil and artemisinin
Journal of Antimicrobial Chemotherapy, 2007Co-Authors: Wendy W. J. Van De Sande, Thomas V Riley, Ahmed Hassan Fahal, Henri A. Verbrugh, Alex Van BelkumAbstract:Objectives: Eumycetoma caused by Madurella mycetomatis is treated with surgery and high doses of itraconazole and ketoconazole. These agents are toxic, and new therapies are required. Methods: MICs were determined for artemisinin and Tea Tree Oil, two natural herbal compounds. Results: Artemisinin was not active against M. mycetomatis, but Tea Tree Oil did inhibit its growth. Since Tea Tree Oil's prime component easily penetrates the skin, Tea Tree Oil could be a useful agent in the treatment of eumycetoma. Conclusions: Tea Tree Oil is active in vitro against M. mycetomatis.
-
susceptibility of pseudomonads to melaleuca alternifolia Tea Tree Oil and components
Journal of Antimicrobial Chemotherapy, 2006Co-Authors: Chelsea J Papadopoulos, Katherine A Hammer, Christine F Carson, Thomas V RileyAbstract:Objectives: Thirty isolates of Pseudomonas aeruginosa, 15 isolates of Pseudomonas putida and 11 isolates of Pseudomonas fluorescens were tested for susceptibility to Tea Tree Oil (TTO), the essential Oil of Melaleuca alternifolia, and the components terpinen-4-ol, a-terpineol, cineole, g-terpinene and r-cymene. Methods: MICs were determined by broth microdilution in Mueller–Hinton medium supplemented with 0.002% (v/v) Tween 80. Results: The MIC90 of TTO for all isolates tested was 4% (v/v) or less. Susceptibility to components tested varied between species.
-
melaleuca alternifolia Tea Tree Oil a review of antimicrobial and other medicinal properties
Clinical Microbiology Reviews, 2006Co-Authors: Christine F Carson, Katherine A Hammer, Thomas V RileyAbstract:Complementary and alternative medicines such as Tea Tree (melaleuca) Oil have become increasingly popular in recent decades. This essential Oil has been used for almost 100 years in Australia but is now available worldwide both as neat Oil and as an active component in an array of products. The primary uses of Tea Tree Oil have historically capitalized on the antiseptic and anti-inflammatory actions of the Oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the Oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the Oil is briefly discussed.
Christine F Carson - One of the best experts on this subject based on the ideXlab platform.
-
therapeutic potential of Tea Tree Oil for scabies
American Journal of Tropical Medicine and Hygiene, 2016Co-Authors: Jackson Thomas, Christine F Carson, Shelley F. Walton, Katherine A Hammer, Greg Peterson, Mark Naunton, Rachel Davey, Tim Spelman, Pascale Dettwiller, Greg KyleAbstract:Globally, scabies affects more than 130 million people at any time. In the developed world, outbreaks in health institutions and vulnerable communities result in a significant economic burden. A review of the literature demonstrates the emergence of resistance toward classical scabicidal treatments and the lack of effectiveness of currently available scabicides in reducing the inflammatory skin reactions and pyodermal progression that occurs in predisposed patient cohorts. Tea Tree Oil (TTO) has demonstrated promising acaricidal effects against scabies mites in vitro and has also been successfully used as an adjuvant topical medication for the treatment of crusted scabies, including cases that did not respond to standard treatments. Emerging acaricide resistance threatens the future usefulness of currently used gold standard treatments (oral ivermectin and topical permethrin) for scabies. The imminent development of new chemical entities is doubtful. The cumulative acaricidal, antibacterial, antipruritic, anti-inflammatory, and wound healing effects of TTO may have the potential to successfully reduce the burden of scabies infection and the associated bacterial complications. This review summarizes current knowledge on the use of TTO for the treatment of scabies. On the strength of existing data for TTO, larger scale, randomized controlled clinical trials are warranted.
-
effect of habituation to Tea Tree melaleuca alternifolia Oil on the subsequent susceptibility of staphylococcus spp to antimicrobials triclosan Tea Tree Oil terpinen 4 ol and carvacrol
International Journal of Antimicrobial Agents, 2013Co-Authors: Natalie A Thomsen, Thomas V Riley, Katherine A Hammer, Alex Van Belkum, Christine F CarsonAbstract:The aim of this study was to seek additional data on the antimicrobial susceptibility of Staphylococcus spp. after habituation to low levels of the topical antimicrobial agent Tea Tree (Melaleuca alternifolia) Oil. Meticillin-susceptible Staphylococcus aureus (MSSA), meticillin-resistant S. aureus (MRSA) and coagulase-negative staphylococci (CoNS) were habituated to 0.075% Tea Tree Oil for 3 days. Subsequently, the susceptibility of five isolates each of MSSA, MRSA and CoNS to fusidic acid, mupirocin, chloramphenicol, linezolid and vancomycin was determined by Etest, and susceptibility to Tea Tree Oil, terpinen-4-ol, carvacrol and triclosan was determined by agar dilution. Following habituation to 0.075% Tea Tree Oil, antimicrobial MICs differed between control and habituated isolates on 33 occasions (out of a possible 150), with MICs being higher in habituated isolates on 22 occasions. Using clinical breakpoint criteria, one MSSA isolate changed susceptibility category from vancomycin-susceptible (MIC=2 μg/mL) to intermediate susceptibility (MIC=3 μg/mL) after habituation in one of two replicates. For the non-antibiotic antimicrobial agents, MICs of habituated and control isolates differed on 12 occasions (out of a possible 120); 10 occasions in MRSA and 2 occasions in MSSA. MICs were higher for habituated isolates on five occasions. However, all the differences were one serial dilution only and were not regarded as significant. Habituation to sublethal concentrations of Tea Tree Oil led to minor changes in MICs of antimicrobial agents, only one of which may have been clinically relevant. There is no evidence to suggest that Tea Tree Oil induces resistance to antimicrobial agents.
-
use of deception to achieve double blinding in a clinical trial of melaleuca alternifolia Tea Tree Oil for the treatment of recurrent herpes labialis
Contemporary Clinical Trials, 2008Co-Authors: Christine F Carson, David Smith, Gail J Lampacher, Thomas V RileyAbstract:Double-blinding is an important and widely implemented feature of clinical trials although its success is rarely assessed. In a randomized, placebo-controlled trial of Tea Tree Oil, an aromatic essential Oil, for the treatment of recurrent herpes labialis (RHL), or cold sores, deception was used to prevent volunteers from identifying their treatment allocation. Volunteers received placebo (n = 102) or Tea Tree Oil (n = 112) ointment in preparation for their next episode of RHL and were told, falsely, that the aroma of the ointments had been changed to prevent identification of the treatment group. At the trial's end, of the volunteers who had used their ointment and presented for treatment assessment (n = 100), approximately 50% correctly guessed their treatment allocation (P = 0.774). Amongst volunteers that had not presented for treatment assessment (n = 114), 12 volunteers did not provide blinding data and 46 did not open their tube. For the 56 volunteers who opened their tube, less than half of those receiving Tea Tree Oil (44.4%) and only a small proportion of those on placebo (17.2%) were able to correctly identify their treatment allocation. Among the volunteers that were not treated, the P-value was 0.083. This study showed that the ethical use of deception may provide effective blinding in challenging circumstances.
-
susceptibility of pseudomonads to melaleuca alternifolia Tea Tree Oil and components
Journal of Antimicrobial Chemotherapy, 2006Co-Authors: Chelsea J Papadopoulos, Katherine A Hammer, Christine F Carson, Thomas V RileyAbstract:Objectives: Thirty isolates of Pseudomonas aeruginosa, 15 isolates of Pseudomonas putida and 11 isolates of Pseudomonas fluorescens were tested for susceptibility to Tea Tree Oil (TTO), the essential Oil of Melaleuca alternifolia, and the components terpinen-4-ol, a-terpineol, cineole, g-terpinene and r-cymene. Methods: MICs were determined by broth microdilution in Mueller–Hinton medium supplemented with 0.002% (v/v) Tween 80. Results: The MIC90 of TTO for all isolates tested was 4% (v/v) or less. Susceptibility to components tested varied between species.
-
melaleuca alternifolia Tea Tree Oil a review of antimicrobial and other medicinal properties
Clinical Microbiology Reviews, 2006Co-Authors: Christine F Carson, Katherine A Hammer, Thomas V RileyAbstract:Complementary and alternative medicines such as Tea Tree (melaleuca) Oil have become increasingly popular in recent decades. This essential Oil has been used for almost 100 years in Australia but is now available worldwide both as neat Oil and as an active component in an array of products. The primary uses of Tea Tree Oil have historically capitalized on the antiseptic and anti-inflammatory actions of the Oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the Oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the Oil is briefly discussed.
Katherine A Hammer - One of the best experts on this subject based on the ideXlab platform.
-
therapeutic potential of Tea Tree Oil for scabies
American Journal of Tropical Medicine and Hygiene, 2016Co-Authors: Jackson Thomas, Christine F Carson, Shelley F. Walton, Katherine A Hammer, Greg Peterson, Mark Naunton, Rachel Davey, Tim Spelman, Pascale Dettwiller, Greg KyleAbstract:Globally, scabies affects more than 130 million people at any time. In the developed world, outbreaks in health institutions and vulnerable communities result in a significant economic burden. A review of the literature demonstrates the emergence of resistance toward classical scabicidal treatments and the lack of effectiveness of currently available scabicides in reducing the inflammatory skin reactions and pyodermal progression that occurs in predisposed patient cohorts. Tea Tree Oil (TTO) has demonstrated promising acaricidal effects against scabies mites in vitro and has also been successfully used as an adjuvant topical medication for the treatment of crusted scabies, including cases that did not respond to standard treatments. Emerging acaricide resistance threatens the future usefulness of currently used gold standard treatments (oral ivermectin and topical permethrin) for scabies. The imminent development of new chemical entities is doubtful. The cumulative acaricidal, antibacterial, antipruritic, anti-inflammatory, and wound healing effects of TTO may have the potential to successfully reduce the burden of scabies infection and the associated bacterial complications. This review summarizes current knowledge on the use of TTO for the treatment of scabies. On the strength of existing data for TTO, larger scale, randomized controlled clinical trials are warranted.
-
treatment of acne with Tea Tree Oil melaleuca products a review of efficacy tolerability and potential modes of action
International Journal of Antimicrobial Agents, 2015Co-Authors: Katherine A HammerAbstract:Over-the-counter acne treatments containing Tea Tree Oil from the plant Melaleuca alternifolia are widely available, and evidence indicates that they are a common choice amongst those self-treating their acne. The aims of this review were to collate and evaluate the clinical evidence on the use of Tea Tree Oil products for treating acne, to review safety and tolerability and to discuss the underlying modes of therapeutic action.
-
effect of habituation to Tea Tree melaleuca alternifolia Oil on the subsequent susceptibility of staphylococcus spp to antimicrobials triclosan Tea Tree Oil terpinen 4 ol and carvacrol
International Journal of Antimicrobial Agents, 2013Co-Authors: Natalie A Thomsen, Thomas V Riley, Katherine A Hammer, Alex Van Belkum, Christine F CarsonAbstract:The aim of this study was to seek additional data on the antimicrobial susceptibility of Staphylococcus spp. after habituation to low levels of the topical antimicrobial agent Tea Tree (Melaleuca alternifolia) Oil. Meticillin-susceptible Staphylococcus aureus (MSSA), meticillin-resistant S. aureus (MRSA) and coagulase-negative staphylococci (CoNS) were habituated to 0.075% Tea Tree Oil for 3 days. Subsequently, the susceptibility of five isolates each of MSSA, MRSA and CoNS to fusidic acid, mupirocin, chloramphenicol, linezolid and vancomycin was determined by Etest, and susceptibility to Tea Tree Oil, terpinen-4-ol, carvacrol and triclosan was determined by agar dilution. Following habituation to 0.075% Tea Tree Oil, antimicrobial MICs differed between control and habituated isolates on 33 occasions (out of a possible 150), with MICs being higher in habituated isolates on 22 occasions. Using clinical breakpoint criteria, one MSSA isolate changed susceptibility category from vancomycin-susceptible (MIC=2 μg/mL) to intermediate susceptibility (MIC=3 μg/mL) after habituation in one of two replicates. For the non-antibiotic antimicrobial agents, MICs of habituated and control isolates differed on 12 occasions (out of a possible 120); 10 occasions in MRSA and 2 occasions in MSSA. MICs were higher for habituated isolates on five occasions. However, all the differences were one serial dilution only and were not regarded as significant. Habituation to sublethal concentrations of Tea Tree Oil led to minor changes in MICs of antimicrobial agents, only one of which may have been clinically relevant. There is no evidence to suggest that Tea Tree Oil induces resistance to antimicrobial agents.
-
susceptibility of pseudomonads to melaleuca alternifolia Tea Tree Oil and components
Journal of Antimicrobial Chemotherapy, 2006Co-Authors: Chelsea J Papadopoulos, Katherine A Hammer, Christine F Carson, Thomas V RileyAbstract:Objectives: Thirty isolates of Pseudomonas aeruginosa, 15 isolates of Pseudomonas putida and 11 isolates of Pseudomonas fluorescens were tested for susceptibility to Tea Tree Oil (TTO), the essential Oil of Melaleuca alternifolia, and the components terpinen-4-ol, a-terpineol, cineole, g-terpinene and r-cymene. Methods: MICs were determined by broth microdilution in Mueller–Hinton medium supplemented with 0.002% (v/v) Tween 80. Results: The MIC90 of TTO for all isolates tested was 4% (v/v) or less. Susceptibility to components tested varied between species.
-
melaleuca alternifolia Tea Tree Oil a review of antimicrobial and other medicinal properties
Clinical Microbiology Reviews, 2006Co-Authors: Christine F Carson, Katherine A Hammer, Thomas V RileyAbstract:Complementary and alternative medicines such as Tea Tree (melaleuca) Oil have become increasingly popular in recent decades. This essential Oil has been used for almost 100 years in Australia but is now available worldwide both as neat Oil and as an active component in an array of products. The primary uses of Tea Tree Oil have historically capitalized on the antiseptic and anti-inflammatory actions of the Oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the Oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the Oil is briefly discussed.
J.t. Callander - One of the best experts on this subject based on the ideXlab platform.
-
Bioactivity of Tea Tree Oil from Melaleuca alternifolia against sheep lice (Bovicola ovis Schrank) in vitro.
Veterinary Parasitology, 2012Co-Authors: Peter James, J.t. CallanderAbstract:Tea Tree Oil (TTO) from the Australian native plant Melaleuca alternifolia has wide ranging bio-active properties, including insecticidal and repellent activity against arthropods. Furthermore, composition of commercially available Australian TTO is specified under an International Organization for Standardization standard (ISO 4730), reducing the potential for variable effects often noted with botanical pesticides. The effect of TTO, meeting the ISO standard for terpinen-4-ol chemotype, was tested against sheep lice (Bovicola ovis Schrank) in a series of laboratory studies. Immersion of wool for 60 s in formulations containing concentrations of 1% TTO and above caused 100% mortality of adult lice and eggs. Exposure to vapours from TTO, delivered as droplets in fumigation chambers and when applied to wool also caused high mortality in both lice and eggs. The main active component of TTO in the fumigant tests was terpinen-4-ol. Treated surface assays and tests with wool where the formulation was allowed to dry before exposure of lice indicated low persistence. These studies demonstrate that TTO is highly toxic to sheep lice and active at concentrations that suggest potential for the development of TTO-based ovine lousicides.
Francesca Mondello - One of the best experts on this subject based on the ideXlab platform.
-
determination of legionella pneumophila susceptibility to melaleuca alternifolia cheel Tea Tree Oil by an improved broth micro dilution method under vapour controlled conditions
Journal of Microbiological Methods, 2009Co-Authors: Francesca Mondello, Antonietta Girolamo, Maria Scaturro, Maria Luisa RicciAbstract:The aim of this study was to determine the in vitro activity of Melaleuca alternifolia Cheel (Tea Tree) Oil (TTO) against 22 strains of Legionella pneumophila of different serogroup and source of isolation. Both a standard broth micro-dilution method, with slight modifications, and a micro-atmosphere diffusion method were used. Furthermore, we have established a simple sealing procedure in the micro-dilution method to determine the antibacterial activity of TTO against Legionella in aqueous phase. The results showed that L. pneumophila, quite irrespective of serogroup and source of isolation, is exquisitely sensitive to TTO, with minimal inhibitory concentration (MIC) ranging from 0.125 to 0.5% v/v, and a bactericidal activity at 0.5% v/v. In addition, we show here that TTO vapours exert critical activity, that must be controlled for reproducible MIC determinations. Overall, our data suggest that TTO could be active as anti-Legionella disinfectant, for control of water system contamination, especially in spas, in small waterlines or in particular respiratory medical devices.
-
terpinen 4 ol the main component of melaleuca alternifolia Tea Tree Oil inhibits the in vitro growth of human melanoma cells
Journal of Investigative Dermatology, 2004Co-Authors: Annarica Calcabrini, Annarita Stringaro, Laura Toccacieli, Stefania Meschini, Manuela Marra, Marisa Colone, Giuseppe Arancia, Agnese Molinari, Giuseppe Salvatore, Francesca MondelloAbstract:The search for innovative therapeutic approaches based on the use of new substances is gaining more interest in clinical oncology. In this in vitro study the potential anti-tumoral activity of Tea Tree Oil, distilled from Melaleuca alternifolia, was analyzed against human melanoma M14 WT cells and their drug-resistant counterparts, M14 adriamicin-resistant cells. Both sensitive and resistant cells were grown in the presence of Tea Tree Oil at concentrations ranging from 0.005 to 0.03%. Both the complex Oil (Tea Tree Oil) and its main active component terpinen-4-ol were able to induce caspase-dependent apoptosis of melanoma cells and this effect was more evident in the resistant variant cell population. Freeze-fracturing and scanning electron microscopy analyses suggested that the effect of the crude Oil and of the terpinen-4-ol was mediated by their interaction with plasma membrane and subsequent reorganization of membrane lipids. In conclusion, Tea Tree Oil and terpinen-4-ol are able to impair the growth of human M14 melanoma cells and appear to be more effective on their resistant variants, which express high levels of P-glycoprotein in the plasma membrane, overcoming resistance to caspase-dependent apoptosis exerted by P-glycoprotein-positive tumor cells.
-
in vitro and in vivo activity of Tea Tree Oil against azole susceptible and resistant human pathogenic yeasts
Journal of Antimicrobial Chemotherapy, 2003Co-Authors: Francesca Mondello, Giuseppe Salvatore, Antonietta Girolamo, Flavia De Bernardis, Antonio CassoneAbstract:A Tea Tree Oil (TTO) preparation of defined chemical composition was studied, using a micro- broth method, for its in vitro activity against 115 isolates of Candida albicans, other Candida species and Cryptococcus neoformans. The fungal strains were from HIV-seropositive subjects, or from an established type collection, including reference and quality control strains. Fourteen strains of C. albicans resistant to fluconazole and/or itraconazole were also assessed. The same preparation was also tested in an experimental vaginal infection using fluconazole- itraconazole-susceptible or -resistant strains of C. albicans. TTO was shown to be active in vitro against all tested strains, with MICs ranging from 0.03% (for C. neoformans) to 0.25% (for some strains of C. albicans and other Candida species). Fluconazole- and/or itraconazole-resistant C. albicans isolates had TTO MIC 50 s and MIC 90 s of 0.25% and 0.5%, respectively. TTO was highly efficacious in accelerating C. albicans clearance from experimentally infected rat vagina. Three post-challenge doses of TTO (5%) brought about resolution of infection regardless of whether the infecting C. albicans strain was susceptible or resistant to fluconazole. Overall, the use of a reliable animal model of infection has confirmed and extended our data on the therapeutic effectiveness of TTO against fungi, in particular against C. albicans.
