82 research outputs found
Medical-grade honey enriched with antimicrobial peptides has enhanced activity against antibiotic-resistant pathogens
Honey has potent activity against both antibiotic-sensitive and -resistant bacteria, and is an interesting agent for topical antimicrobial application to wounds. As honey is diluted by wound exudate, rapid bactericidal activity up to high dilution is a prerequisite for its successful application. We investigated the kinetics of the killing of antibiotic-resistant bacteria by RS honey, the source for the production of Revamil® medical-grade honey, and we aimed to enhance the rapid bactericidal activity of RS honey by enrichment with its endogenous compounds or the addition of antimicrobial peptides (AMPs). RS honey killed antibiotic-resistant isolates of Pseudomonas aeruginosa, Staphylococcus epidermidis, Enterococcus faecium, and Burkholderia cepacia within 2 h, but lacked such rapid activity against methicillin-resistant S. aureus (MRSA) and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. It was not feasible to enhance the rapid activity of RS honey by enrichment with endogenous compounds, but RS honey enriched with 75 μM of the synthetic peptide Bactericidal Peptide 2 (BP2) showed rapid bactericidal activity against all species tested, including MRSA and ESBL E. coli, at up to 10–20-fold dilution. RS honey enriched with BP2 rapidly killed all bacteria tested and had a broader spectrum of bactericidal activity than either BP2 or honey alone
Honey health benefits and uses in medicine
The generation of reactive oxygen species (ROS) and other free radicals during
metabolism is an essential and normal process that ideally is compensated through
the antioxidant system. However, due to many environmental, lifestyle, and pathological
situations, free radicals and oxidants can be produced in excess, resulting in
oxidative damage of biomolecules (e.g., lipids, proteins, and DNA). This plays a
major role in the development of chronic and degenerative illness such as cancer,
autoimmune disorders, aging, cataract, rheumatoid arthritis, cardiovascular, and
neurodegenerative diseases (Pham-Huy et al. 2008; Willcox et al. 2004). The human
body has several mechanisms to counteract oxidative stress by producing antioxidants, which are either naturally synthetized in situ, or externally supplied
through foods, and/or supplements (Pham-Huy et al. 2008).info:eu-repo/semantics/publishedVersio
International standardisation work on the measurement of radon in air and water
Radon is considered to be the main source of human exposure to natural radiation. As stated by the World Health Organization, the exposure due to the inhalation of indoor radon is much greater than the one via the ingestion of water as radon degasses from water during handling. In response to these concerns about the universal presence of radon, environmental assessment studies are regularly commissioned to assess the radon exposure of public and workers. The credibility of such studies relies on the quality and reliability of radon analysis as well as on the sample representativeness of the radiological situation. The standard-setting approach, based on consensus, seemed to lend itself to a settlement of technical aspects of potential comparison. At present, two Working Groups of the International Standardization Organization are focussing on drafting standards on radon and its decay products measurement in air and water. These standards, which aim for a set of rigorous metrology practices, will be useful for persons in charge of the initial characterisation of a site with respect to natural radioactivity as well as to those performing the routine surveillance of specific site
Effects of Hydrogen Peroxide on Wound Healing in Mice in Relation to Oxidative Damage
10.1371/journal.pone.0049215PLoS ONE711
Appraising the Qualities of Social Work Students’ Theoretical Knowledge: A Qualitative Exploration
Van Bommel, M., Boshuizen, H. P. A., & Kwakman, K. (2012). Appraising the qualities of social work students' theoretical knowledge: A qualitative exploration. Vocations and Learning, 5, 277-295. doi:10.1007/s12186-012-9078-9Higher professional education aims to prepare students for entering practice with an adequate theoretical body of knowledge. In constructivist programmes, authentic learning contexts and self-directed learning are assumed to support knowledge learning and the transition from education to practice. Through an in-depth exploration, this case study aimed at defining and assessing the qualities of social work students’ theoretical knowledge at initial qualification. Participants were final-year bachelor’s students (n=18) in a constructivist professional programme of social work. Students’ knowledge concerning a real-life practical case was elicited through an interview and a form of concept mapping. A six-step procedure was used for a qualitative appraisal of students’ knowledge with the assistance of seven expert teachers. During this procedure an instrument for analysing knowledge qualities was developed, comprising 13 aspects representing four features of expert knowledge: extent, depth, structure, and critical control. Results showed that 13 students received high appraisals for their knowledge extent and depth. Only 4 students received high appraisals for knowledge structure and critical control. 5 Students who received overall lower appraisals seemed inhibited to show their knowledge qualities by preoccupations with self-concerns about their own professional role. Conclusion is that the majority of students needs more learning support for knowledge structure and critical control than offered by their constructivist programme. Further research is needed into the personal factors that influence students’ theoretical knowledge learning and which knowledge qualities can be reached by young adults in a four year educational programme.Hogeschool Arnhem Nijmege
Volatile Compounds in Honey: A Review on Their Involvement in Aroma, Botanical Origin Determination and Potential Biomedical Activities
Volatile organic compounds (VOCs) in honey are obtained from diverse biosynthetic pathways and extracted by using various methods associated with varying degrees of selectivity and effectiveness. These compounds are grouped into chemical categories such as aldehyde, ketone, acid, alcohol, hydrocarbon, norisoprenoids, terpenes and benzene compounds and their derivatives, furan and pyran derivatives. They represent a fingerprint of a specific honey and therefore could be used to differentiate between monofloral honeys from different floral sources, thus providing valuable information concerning the honey’s botanical and geographical origin. However, only plant derived compounds and their metabolites (terpenes, norisoprenoids and benzene compounds and their derivatives) must be employed to discriminate among floral origins of honey. Notwithstanding, many authors have reported different floral markers for honey of the same floral origin, consequently sensory analysis, in conjunction with analysis of VOCs could help to clear this ambiguity. Furthermore, VOCs influence honey’s aroma described as sweet, citrus, floral, almond, rancid, etc. Clearly, the contribution of a volatile compound to honey aroma is determined by its odor activity value. Elucidation of the aroma compounds along with floral origins of a particular honey can help to standardize its quality and avoid fraudulent labeling of the product. Although only present in low concentrations, VOCS could contribute to biomedical activities of honey, especially the antioxidant effect due to their natural radical scavenging potential
The Antibacterial Activity of Honey Derived from Australian Flora
Chronic wound infections and antibiotic resistance are driving interest in
antimicrobial treatments that have generally been considered complementary,
including antimicrobially active honey. Australia has unique native flora and
produces honey with a wide range of different physicochemical properties. In
this study we surveyed 477 honey samples, derived from native and exotic plants
from various regions of Australia, for their antibacterial activity using an
established screening protocol. A level of activity considered potentially
therapeutically useful was found in 274 (57%) of the honey samples, with
exceptional activity seen in samples derived from marri (Corymbia
calophylla), jarrah (Eucalyptus marginata) and
jellybush (Leptospermum polygalifolium). In most cases the
antibacterial activity was attributable to hydrogen peroxide produced by the
bee-derived enzyme glucose oxidase. Non-hydrogen peroxide activity was detected
in 80 (16.8%) samples, and was most consistently seen in honey produced
from Leptospermum spp. Testing over time found the hydrogen
peroxide-dependent activity in honey decreased, in some cases by 100%,
and this activity was more stable at 4°C than at 25°C. In contrast, the
non-hydrogen peroxide activity of Leptospermum honey samples
increased, and this was greatest in samples stored at 25°C. The stability of
non-peroxide activity from other honeys was more variable, suggesting this
activity may have a different cause. We conclude that many Australian honeys
have clinical potential, and that further studies into the composition and
stability of their active constituents are warranted
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