Putting it into practice: Infection control professionals' perspectives on early career nursing graduates' microbiology and infection control knowledge and practice.

BACKGROUND: The microbiology component of Australian undergraduate nursing programmes varies considerably. Any actual or potential impact of this variation on infection control practice, as a nursing graduate, is relatively unknown. AIMS: The aim of this study was to explore infection control professionals' perceptions of the importance of microbiology and infection control training in undergraduate nursing curricula and the perceived retention of that knowledge and its transferability to practice. METHOD: Semi-structured interviews were conducted with eight infection control professionals from a range of hospital settings in Australia. FINDINGS: Four main themes emerged: Theory versus practice, importance of role modelling, disjunction between university curricula and 'the real world,' and learning in context. CONCLUSION: As the underpinning element of infection control practice, the role of microbiology education and training in nursing education will benefit from review. Further discussions about the nature and timing of theoretical microbiology content and assessment of undergraduate students' microbiology knowledge to ensure retention and appropriate application of that knowledge in practice are urgently needed.

Genetic characterization of equine adenovirus type 1.

Two known serotypes of equine adenovirus (EAdV), equine adenovirus type 1 (EAdV-1) and equine adenovirus type 2 (EAdV-2) have been isolated from horses. EAdV-1 is predominantly associated with upper respiratory tract infections while EAdV-2 appears to be associated with gastrointestinal infections in horses. In this report the EAdV-1 genome has been sequenced for the first time. The EAdV-1 genome encoded genes are characteristic of the Mastadenovirus genus such as protein V and IX. Unexpectedly, phylogenetic reconstructions also revealed a close relationship between EAdV-1 and two recently characterized bat adenoviruses. The results of this study suggest that EAdV-1 may share a common ancestor with canine and bat adenoviruses.

Evaluating the effects of the essential oils Leptospermum scoparium (manuka) and Kunzea ericoides (kanuka) on radiotherapy induced mucositis: a randomized, placebo controlled feasibility study.

This study evaluated the effects of an essential oil mouthwash on radiation induced mucositis of the oropharyngeal area during treatment for head and neck cancers. Nineteen adult patients completed the randomized placebo controlled trial which involved the use of a gargle containing 2 drops of a 1:1 mix of the essential oils of manuka (Leptospermum scoparium) and kanuka (Kunzea ericoides) in water. Those in the essential oil gargle group were observed to have a delayed onset of mucositis and reduced pain and oral symptoms relative to placebo (gargling with water) and the control ('usual care') groups. In addition those in the essential oil group were seen to have less weight loss (1% loss) than the other two groups (control 2.5%, placebo 4.5%). However a significant limitation in this study was the small sample size. Although the results from this feasibility study support the hypothesis that very small volumes of manuka and kanuka used in a gargle can provide a positive effect on the development of radiation induced mucositis, further research is required to confirm this finding. Randomization was applied according to the timing of the patient's entering the trial as well as their physical ability to gargle. Confirmation of these findings would pave the way for introduction of a simple, yet effective treatment for a condition which causes considerable discomfort and for which there is currently no definitive treatment.

Increased tumor localization and reduced immune response to adenoviral vector formulated with the liposome DDAB/DOPE.

UNLABELLED: We aimed to increase the efficiency of adenoviral vectors by limiting adenoviral spread from the target site and reducing unwanted host immune responses to the vector. We complexed adenoviral vectors with DDAB-DOPE liposomes to form adenovirus-liposomal (AL) complexes. AL complexes were delivered by intratumoral injection in an immunocompetent subcutaneous rat tumor model and the immunogenicity of the AL complexes and the expression efficiency in the tumor and other organs was examined. Animals treated with the AL complexes had significantly lower levels of beta-galactosidase expression in systemic tissues compared to animals treated with the naked adenovirus (NA) (P<0.05). The tumor to non-tumor ratio of beta-galactosidase marker expression was significantly higher for the AL complex treated animals. NA induced significantly higher titers of adenoviral-specific antibodies compared to the AL complexes (P<0.05). The AL complexes provided protection (immunoshielding) to the adenovirus from neutralizing antibody. Forty-seven percent more beta-galactosidase expression was detected following intratumoral injection with AL complexes compared to the NA in animals pre-immunized with adenovirus. CONCLUSIONS: Complexing of adenovirus with liposomes provides a simple method to enhance tumor localization of the vector, decrease the immunogenicity of adenovirus, and provide protection of the virus from pre-existing neutralizing antibodies.

Antiparasitic activity of two Lavandula essential oils against Giardia duodenalis, Trichomonas vaginalis and Hexamita inflata.

Two essential oils derived from Lavandula angustifolia and Lavandula x intermedia were investigated for any antiparasitic activity against the human protozoal pathogens Giardia duodenalis and Trichomonas vaginalis and the fish pathogen Hexamita inflata: all of which have significant infection and economic impacts. The study has demonstrated that low (< or = 1%) concentrations of L. angustifolia and L. x intermedia oil can completely eliminate T. vaginalis, G. duodenalis and H. inflata in vitro. At 0.1% concentration, L. angustifolia oil was found to be slightly more effective than L x intermedia oil against G. duodenalis and H. inflata. The potential applications are discussed.

Antibacterial activity of essential oils from Australian native plants.

To date, of the Australian essential oils, only tea tree (Melaleuca alternifolia) and Eucalyptus spp. have undergone extensive investigation. In this study a range of Australian essential oils, including those from Anethole anisata, Callistris glaucophyllia, Melaleuca spp. and Thyptomine calycina, were assayed for in vitro antibacterial activity. M. alternifolia was also included for comparison purposes. Activity was determined using standard disc diffusion assays with each oil assayed at 100%, 10% and 1% against five bacteria (Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa and Alcaligenes faecalis) and the yeast, Candida albicans. All bacteria, with the exception of Ps. aeruginosa, were susceptible to one or more of the essential oils at 100%, with only Eremophilia mitchelli inhibiting the growth of any bacteria at 1% (inhibition of Sal. typhimurium). Where multiple samples of a single oil variety were tested variability in activity profiles were noted. This suggests that different methods of preparation of essential oils, together with variability in plant chemical profiles has an impact on whether or not the essential oil is of use as an antimicrobial agent. These results show that essential oils from Australian plants may be valuable antimicrobial agents for use alone or incorporated into cosmetics, cleaning agents and pharmaceutical products.

Riverina high school students’ views of biotechnology

A survey investigating the knowledge and perception of biotechnology by high school students living in the rural Riverina region of New South Wales, Australia, was undertaken. Data relating to the student’ preferred and trusted information sources was also gathered. This study has demonstrated that at least two-thirds of students had a good knowledge of medical biotechnology issues, however, a significant proportion of the students did have concerns about the use and/or safety of biotechnology. Nearly 90% of the respondents would like further information on biotechnology. In agreement with other surveys, the students reported an apparent lack of trust in articles from the lay press (newspapers, television, radio) and yet still report that these media as the preferred information source. Interestingly, the high school students demonstrated a higher than national average acceptance of biotechnology.

Modification of liposomal concentration in liposome/adenoviral complexes allows significant protection of adenoviral vectors from neutralising antibody, in vitro.

Adenoviral vectors have been commonly used in gene therapy protocols, however the success of their use is often limited by the induction of host immunity to the vector. Following exposure to the adenoviral vector, adenoviral-specific neutralising antibodies are produced which limits further administration. This study examines the efficacy of complexing liposomes to adenovirus for the protection of the adenovirus from neutralising antibodies in an in vitro setting. Dimethyldioctadecylammonium bromide (DDAB)-dioleoyl-l-phosphatidylethanolamine (DOPE) liposomes were bound at varying concentrations to adenovirus to form AL complexes and tested these complexes' ability to prevent adenoviral neutralisation. It is shown that by increasing the concentration of liposomes in the adenoviral-liposome (AL) complexes we can increase the level of immuno-shielding afforded the adenovirus. It is also shown that the increase in liposomal concentration may lead to drawbacks such as increased cytotoxicity and reductions in expression levels.

Antibacterial activity of 13 honeys against Escherichia coli and Pseudomonas aeruginosa.

In this study the activity of 13 honeys, including three commercial antibacterial honeys, against Escherichia coli and Pseudomonas aeruginosa was determined. Antibacterial activity of the honeys was assayed using standard well diffusion methods. All honeys, and an artificial honey, were tested at four concentrations (10%, 5%, 2.5%, and 1% wt/vol) against E. coli and P. aeruginosa, and zones of inhibition were measured. All honeys tested had an inhibitory effect on the growth of E. coli and P. aeruginosa, with one honey still having activity against E. coli and three having activity against P. aeruginosa at 2.5%. No honey was active at 1% concentrations. E. coli was more susceptible to inhibition by the honeys used in this study than was P. aeruginosa. In this study we have demonstrated that several honeys, in addition to commercial antibacterial honeys, can inhibit E. coli and P. aeruginosa and may have potential as therapeutic honeys.

Microsphere-liposome complexes protect adenoviral vectors from neutralising antibody without losses in transfection efficiency, in-vitro.

Adenoviral vectors have been commonly used in gene therapy protocols but the success of their use is often limited by the induction of host immunity to the vector. Following exposure to the adenoviral vector, adenoviral-specific neutralising antibodies are produced, which limits further administration. This study examines the effectiveness of a novel combination of microspheres and liposomes for the shielding of adenovirus from neutralising antibodies in an in-vitro setting. We show that liposomes are effective in the protection of adenovirus from neutralising antibody and that the conjugation of these complexes to microspheres augments the level of protection. This study further reveals that previously neutralised adenovirus may still be transported into the cell via liposome-cell interactions and is still capable of expressing its genes, making this vector an effective tool for circumvention of the humoral immune response. We also looked at possible side effects of using the complexes, namely increases in cytotoxicity and reductions in transfection efficiency. Our results showed that varying the liposome:adenovirus ratio can reduce the cytotoxicity of the vector as well as increase the transfection efficiency. In addition, in cell lines that are adenoviral competent, transfection efficiencies on par with uncomplexed adenoviral vectors were achievable with the combination vector.

In-vitro evaluation of ion-exchange microspheres for the sustained release of liposomal-adenoviral conjugates.

This study looks at the development of a novel combination vector consisting of adenovirus conjugated to liposomes (AL complexes) bound to cation-exchanging microspheres (MAL complexes). With adenovirus having a net negative charge and the liposomes a net positive charge it was possible to modify the net charge of the AL complexes by varying the concentrations of adenovirus to liposomes. The modification of the net charge resulted in altered binding and release characteristics. Of the complexes tested, the 5:1 and 2:1 ratio AL complexes were able to be efficiently bound by the microspheres and exhibited sustained release over 24 h. The 1:1 and 1:2 AL complexes, however, bound poorly to the microspheres and were rapidly released. In addition the MAL complexes also were able to reduce the toxicity of the AL complexes, which was seen with the 10:1 ratio. The AL complexes showed considerably more toxicity alone than in combination with microspheres, highlighting a potential benefit of this vector.

Analysis of essential oil of Satureja thymbra by hydrodistillation, thermal desorber, and headspace GC/MS techniques and its antimicrobial activity.

The essential oil composition of Satureja thymbra was analyzed by direct thermal desorber and Headspace GC/MS analysis methods. Its constituents were determined to be mainly carvacrol (40.15%), gamma-terpinene (26.56%), p-cymene (16.39%), and thymol (13.16%). The other techniques, thermal desorber and Headspace GC/MS, were used for the plant leaves at three different temperature, which showed similar results. The thermal desorber GC/MS gave better and more sensitive results than Headspace GC/MS. The essential oil was found to be active against the bacteria Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Shigella sonnei, and Staphylococcus aureus and the yeast Candida albicans.

Pre-treatment with a non-therapeutic dose of cisplatin increases solid tumour response to liposomal-p53 gene therapy- An in vivo study.

Successful liposomal-mediated gene therapy is often limited by poor transfection efficiencies. One method previously shown to increase the efficiency of liposomal gene delivery is through the administration of a non-therapeutic dose of the chemotherapeutic drug cisplatin prior to lipofection. The currents study aims to utilise this method to deliver lipoplexes containing the p53 tumour suppressor gene with the aim of increasing therapeutic effect of the p53 gene on a solid tumour in vivo. Rats, implanted with solid salivary adenocarcinomas, were pre-treated with a low dose of cisplatin seven days prior to liposomal mediated p53 treatment. Following treatment with p53, tumour growth, p53 expression and levels of apoptosis were examined and compared to animals treated with p53 without cisplatin pre-treatment and a saline control. Tumours that had been pre-treated with cisplatin prior to p53-lipofection were significantly smaller than both the saline control and the non-cisplatin treated tumours. Saline treated tumours increased in size by an average of 164% over a 96-hour period compared to 64% and 101% for the cisplatin and non-cisplatin p53-liposome treated tumours. The cisplatin pre-treated tumours resulted in significantly higher levels of apoptosis surrounding the treatment site and exhibited prolonged p53 expression when compared to the non-cisplatin pre-treated tumours. The results suggest that the use of cisplatin to pre-sensitise tumours to lipofection has significant benefits when used in conjunction with p53.

Antibacterial activity of berry fruits used for culinary purposes.

Increasing interest in the health benefits of various culinary berries has led to investigation of their antibacterial activity. Commercial raspberry, blackcurrant, cranberry, and blackberry cordials (100% fruit) as well as fresh berries were assessed for their ability to inhibit the growth of various bacteria and the yeast Candida albicans. Three of the six raspberry cordials and the blackcurrant cordial inhibited all 12 bacteria and C. albicans at dilutions of 1:5. Bacteria showed varying susceptibilities to the remaining cordials. All cordials inhibited the growth of Mycobacterium phlei. Of the fresh berries, mulberries and boysenberries did not inhibit any bacteria, and the remaining berries inhibited the growth of varying numbers of bacteria. There was no correlation between gram-positive or gram-negative bacterial status and susceptibility to the berries. It is suggested that the antibacterial activity of these berries may be of benefit as a means of water purification for suspect water supplies or to enhance shelf life when incorporated into food products.

Bioactivity of Backhousia citriodora: antibacterial and antifungal activity.

Backhousia citriodora products are used as bushfoods and flavorings and by the aromatherapy industry. The antimicrobial activity of 4 samples of B. citriodora oil, leaf paste, commercial tea (0.2 and 0.02 g/mL), and hydrosol (aqueous distillate) were tested against 13 bacteria and 8 fungi. Little or no activity was found to be associated with the leaf tea and hydrosol, respectively. Leaf paste displayed antimicrobial activity against 7 bacteria including Clostridium perfringens, Pseudomonas aeruginosa, and a hospital isolate of methicillin resistant Staphylococcus aureus (MRSA). The 4 essential oils were found to be effective antibacterial and antifungal agents; however, variation was apparent between oils that did not correlate with citral content. The antimicrobial activity of B. citriodoraessential oils was found to be greater than that of citral alone and often superior to Melaleuca alternifolia essential oil. B. citriodora has significant antimicrobial activity that has potential as an antiseptic or surface disinfectant or for inclusion in foods as a natural antimicrobial agent.