Controlling bacterial growth and inactivation using thin film-based surface acoustic waves.

Formation of bacterial films on structural surfaces often leads to severe contamination of medical devices, hospital equipment, implant materials, etc., and antimicrobial resistance of microorganisms has indeed become a global health issue. Therefore, effective therapies for controlling infectious and pathogenic bacteria are urgently needed. Being a promising active method for this purpose, surface acoustic waves (SAWs) have merits such as nanoscale earthquake-like vibration/agitation/radiation, acoustic streaming induced circulations, and localised acoustic heating effect in liquids. However, only a few studies have explored controlling bacterial growth and inactivation behaviour using SAWs. In this study, we proposed utilising piezoelectric thin film-based SAW devices on a silicon substrate for controlling bacterial growth and inactivation with and without using ZnO micro/nanostructures. Effects of SAW powers on bacterial growth for two types of bacteria, i.e., E. coli and S. aureus, were evaluated. Varied concentrations of ZnO tetrapods were also added into the bacterial culture to study their effects and the combined antimicrobial effects along with SAW agitation. Our results showed that when the SAW power was below a threshold (e.g., about 2.55 W in this study), the bacterial growth was apparently enhanced, whereas the further increase of SAW power to a high power caused inactivation of bacteria. Combination of thin film SAWs with ZnO tetrapods led to significantly decreased growth or inactivation for both E. coli and S. aureus, revealing their effectiveness for antimicrobial treatment. Mechanisms and effects of SAW interactions with bacterial solutions and ZnO tetrapods have been systematically discussed.

Flexible surface acoustic wave technology for enhancing transdermal drug delivery.

Transdermal drug delivery provides therapeutic benefits over enteric or injection delivery because its transdermal routes provide more consistent concentrations of drug and avoid issues of drugs affecting kidneys and liver functions. Many technologies have been evaluated to enhance drug delivery through the relatively impervious epidermal layer of the skin. However, precise delivery of large hydrophilic molecules is still a great challenge even though microneedles or other energized (such as electrical, thermal, or ultrasonic) patches have been used, which are often difficult to be integrated into small wearable devices. This study developed a flexible surface acoustic wave (SAW) patch platform to facilitate transdermal delivery of macromolecules with fluorescein isothiocyanates up to 2000 kDa. Two surrogates of human skin were used to evaluate SAW based energized devices, i.e., delivering dextran through agarose gels and across stratum corneum of pig skin into the epidermis. Results showed that the 2000 kDa fluorescent molecules have been delivered up to 1.1 mm in agarose gel, and the fluorescent molecules from 4 to 2000 kDa have been delivered up to 100 µm and 25 µm in porcine skin tissue, respectively. Mechanical agitation, localised streaming, and acousto-thermal effect generated on the skin surface were identified as the main mechanisms for promoting drug transdermal transportation, although micro/nanoscale acoustic cavitation induced by SAWs could also have its contribution. SAW enhanced transdermal drug delivery is dependent on the combined effects of wave frequency and intensity, duration of applied acoustic waves, temperature, and drug molecules molecular weights.

Impact of regional multi-disciplinary team on the management of complex urogynaecology conditions.

INTRODUCTION AND HYPOTHESIS: Following the publication of the National Institute for Health and Care Excellence guidelines on the management of pelvic floor dysfunction, articles speculating on the benefits and costs of local and regional multi-disciplinary teams (MDTs) have been in circulation. To date, there has been no formal assessment of the impact of a regional MDT on the management of women with complex urogynaecological conditions. METHODS: Throughout the existence of the West of Scotland (WoS) Regional Urogynaecology MDT, from May 2010 to December 2015, 60 patients with complex Urogynaecology conditions were discussed. Data were collected on presenting condition, pre- and post-MDT management plans, and treatment outcomes. RESULTS: The average age was 52.6 years (range 21-91 years). All meetings had at least 1 urogynaecologist, 1 gynaecologist, 1 reconstructive female urologists, 1 urodynamicist and, on average, 3 continence nurses, 4 physiotherapists, as well as 1 clinical librarian to conduct a literature search and 1 secretary for administrative support. The majority of the referrals dealt with urinary incontinence (n=34) and 8 patients presented with mesh complications alongside other pelvic floor disorders. The MDT made changes to the original referrer's management plan in at least 25 (41.7%) patient presentations. Twenty-two out of all the patients discussed (36.7%) were reported as cured or improved in their condition following the MDT-recommended management. CONCLUSION: The WoS Regional Urogynaecology MDT had a positive impact on the management of women presenting with complex condition(s). Cross-sharing of resources between hospitals within the region provided a wider range of management plans, better tailored to each individual.

An immunodetection assay developed using cobra cytotoxin-specific antibodies: Potential diagnostics for cobra envenoming.

Cobra (Naja spp.) envenoming is a life-threatening medical emergency, and a correct diagnosis is crucial to initiating timely and appropriate antivenom treatment. However, snakebite diagnostics remain unavailable in Southeast Asia. This study, therefore, developed an immunodetection assay with a potential diagnostic application for cobra envenoming. The cytotoxin of Naja kaouthia (Thai Monocled Cobra) (Nk-CTX) was purified from its venom to produce CTX-specific antibodies in rabbits and chickens. A double-antibody sandwich enzyme-linked immunosorbent assay was developed using the purified anti-Nk-CTX antibodies (immunoglobulin G and immunoglobulin Y), and its selectivity, specificity, and sensitivity for the venoms of five major cobra species in Southeast Asia (N. kaouthia, Naja sumatrana, Naja sputatrix, Naja siamensis, and Naja philippinensis) were studied. The results showed the immunoassay discriminates cobra venoms from other species commonly implicated in snakebites in Southeast Asia, i.e., the Malayan Krait, Many-banded Krait, King Cobra, Eastern Russell's Viper, Malayan Pit Viper and White-lipped Pit Viper. The immunoassay has a high sensitivity for the five cobra venoms, with detection limits (LoD) ranging from 0.6 to 2.6 ng/ml. Together, the findings suggest the potential diagnostic application of the cytotoxin immunoassay for cobra envenoming. The immunoassay was found to exhibit high immunoreactivity toward ten Asiatic cobra venoms (absorbance > 1.5), in contrast to African cobra venoms with low immunoreactivity (absorbance < 0.9). Considering the varying CTX antigenicity between Asiatic and African cobras, the immunoassay for African cobras should utilize antibodies produced specifically from the cytotoxins of African cobra venoms.

Development, validation and initial evaluation of patient-decision aid (SUI-PDA©) for women considering stress urinary incontinence surgery.

INTRODUCTION AND HYPOTHESIS: Following the design, face validation and publication of a novel PDA for women considering SUI surgery, the main objective of the study is to evaluate the usefulness of SUI-PDA© by using a validated tool to obtain patient feedback. METHODS: From July 2018 to March 2019, the PDA, already incorporated into the patient care pathway, was objectively evaluated using the Decisional Conflict Scale (DCS) to determine patients' views. Patients recorded their values and reasons for requests and declines of treatment. The total DCS score, scores from each DCS subgroup and individual patient responses were calculated and analysed. RESULTS: The mean age of the first 20 patients to complete the DCS was 54 years, the mean BMI was 30.1 and the median parity was 3. The average total DCS score was only 9.29 out of 100 (range 0-29.69) suggesting that the PDA was quite useful for patients considering SUI surgery. Overall, the PDA had largely favourable responses across all five DCS subgroups. The 'informed' subgroup had the best score (6.67) while the 'uncertainty' subgroup had the least favourable score (14.58). Despite the procedure pause, the mesh tape option remained on the PDA; however, no patient had chosen this option, with a large proportion citing 'safety' issues as the main reason. Bulking agent injections were the most popular choice (40.0%) and the most commonly performed procedures (50.0%) mainly because of quicker 'recovery'. The second most popular participant choice was colposuspension (35.0%) followed by autologous fascial sling (25.0%), with women citing 'efficacy' as the main reason behind their choice. CONCLUSION: SUI-PDA© was reported by patients and clinicians to be useful with clinical decision-making for SUI surgery. Further validation in a larger patient group is underway.