Multiplexed microfluidic screening of bacterial chemotaxis.

Microorganism sensing of and responding to ambient chemical gradients regulates a myriad of microbial processes that are fundamental to ecosystem function and human health and disease. The development of efficient, high-throughput screening tools for microbial chemotaxis is essential to disentangling the roles of diverse chemical compounds and concentrations that control cell nutrient uptake, chemorepulsion from toxins, and microbial pathogenesis. Here, we present a novel microfluidic multiplexed chemotaxis device (MCD) which uses serial dilution to simultaneously perform six parallel bacterial chemotaxis assays that span five orders of magnitude in chemostimulant concentration on a single chip. We first validated the dilution and gradient generation performance of the MCD, and then compared the measured chemotactic response of an established bacterial chemotaxis system (Vibrio alginolyticus) to a standard microfluidic assay. Next, the MCD's versatility was assessed by quantifying the chemotactic responses of different bacteria (Psuedoalteromonas haloplanktis, Escherichia coli) to different chemoattractants and chemorepellents. The MCD vastly accelerates the chemotactic screening process, which is critical to deciphering the complex sea of chemical stimuli underlying microbial responses.

Many microorganisms such as bacteria swim to explore their fluid habitats, which range from the human digestive system to the oceans. They can detect minute traces of food, toxins and other chemicals in their environment, and ­ through a process called chemotaxis ­ respond by swimming towards or away from them. Chemical concentrations naturally decrease with distance away from their source, forming gradients. By sensing these chemical gradients, and adjusting their swimming direction accordingly, cells can locate nutrients and other resources in harsh environments as well as avoid toxins and potential predators. Over the past 20 years, laboratory devices that manipulate minute volumes of fluid ­ known as microfluidics devices ­ have been indispensable for studying chemotaxis. They enable researchers to generate gradients of chemicals in carefully designed networks of microscopic channels, controlling the conditions that swimming cells are exposed to and mimicking their natural habitats. However, large-scale studies of chemotaxis have been limited by the sheer range of chemicals that are present at different levels in natural environments. Conventional microfluidic devices often compromise between distinguishing how individual cells behave, precise control over the chemical gradient, or the ability to execute multiple assays at the same time. Here, Stehnach et al. designed a microfluidic device called the Multiplexed Chemotaxis Device. The device generates five streams of precise dilutions of a chemical and then uses these streams ­ alongside a control stream lacking the chemical ­ to measure chemotaxis in six different conditions at the same time. The device was tested using a well-studied bacterium, Vibrio alginolyticus, which is commonly found in marine environments. The device reliably examined the chemotaxis response of the population to various chemicals, was able to carry out multiple assays more rapidly than conventional devices, and can be easily applied to study the response of individual bacteria under the same conditions. The Multiplexed Chemotaxis Device is relatively easy to manufacture using standard methods and therefore has the potential to be used for large-scale chemotaxis studies. In the future, it may be useful for screening new drugs to treat bacterial infections and to help identify food sources for communities of microbes living in marine environments.

A Queensland research support network in emergency healthcare.

PURPOSE: The purpose of this paper is to describe the structure and impact of a Queensland Research Support Network (RSN) in emergency medicine (EM). DESIGN/METHODOLOGY/APPROACH: This paper presents a descriptive summary of EM networks, network evaluations and the structure and development of the Emergency Medicine Foundation's (EMF) RSN in Queensland, including an observational pre- and post-study of research metrics. FINDINGS: In two years, the RSN supported 33 Queensland emergency departments (EDs), of which 14 developed research strategies. There was an increase in research active clinicians, from 23 in 2015 to 181 in 2017. Collaborator engagement increased from 9 in 2015 to 276 in 2017 as did the number of research presentations, from 6 in 2015 to 61 in 2017. EMF experienced a growth in new researchers, with new investigators submitting approximately 60 per cent of grant applications in 2016 and 2017. EMF also received new applications from a further three HHS (taking EMF-funded research activity from 8 to 11 HHS). RESEARCH LIMITATIONS/IMPLICATIONS: This paper describes changes in KPIs and research metrics, which the authors attribute to the establishment of the RSN. However, it is possible that attribution bias plays a role in the KPI improvements. SOCIAL IMPLICATIONS: This network has actively boosted and expanded EM research capacity and capability in Queensland. It provides services, in the form of on-the-ground managers, to develop novice clinician-researchers, new projects and engage entire EDs. This model may be replicated nationwide but requires funding commitment. ORIGINALITY/VALUE: The RSN improves front-line clinician research capacity and capability and increases research activity and collaborations with clear community outcomes. Collaborations were extended to community, primary health networks, non-government organisations, national and international researchers and academic institutions. Evaluating and measuring a network's benefits are difficult, but it is likely that evaluations will help networks obtain funding.

Exploring the use of drug trend data in the regional alcohol and other drug workforce.

OBJECTIVE: Drug trend data can inform appropriate policies to minimise drug-related harm, as well as assist in early detection and prevention. While Australia has a number of monitoring systems, none operate in regional areas. The aim of this study was to explore how drug trend and other data are used by the regional alcohol and other drug workforce. METHOD: Twenty-one key experts from regional Queensland were interviewed between November 2014 and August 2015. Key experts worked in or had contact with the broader alcohol and other drugs field in the Darling Downs area of Queensland. Interviews were analysed thematically. SETTING: Darling Downs, Queensland. RESULTS: Two themes emerged from the analysis. There were differences in workforce needs, with those in the law and criminal justice areas believing they had access to good, current data. Those in the health sector differed, although the majority indicated that there did appear to be a knowledge gap related to their location in a regional area. CONCLUSIONS: Trends in the use of, and harms related to, substance use are well captured in urban areas, but less so in regional areas. This inhibits both our understanding of where substance use is changing, as well as how to best plan and respond.

Do performance and image enhancing drug users in regional Queensland experience difficulty accessing health services?

INTRODUCTION AND AIM: To understand health service access and needs of people who use performance and image enhancing drugs (PIED) in regional Queensland. DESIGN AND METHODS: Semi-structured interviews were conducted with 21 people (n = 19 men) who reported the use of a range of PIEDs, including anabolic-androgenic steroids, human chorionic gonadotropin, growth hormone, clenbuterol, tamoxifen, insulin and peptides. RESULTS: Participants reported accessing a range of services, including needle and syringe programs and pharmacies, for sterile injecting equipment. While PIEDs users attributed some stigma to needle and syringe programs, they were seen as an important service for injecting equipment. Participants reported receiving either positive care from health-care providers, such as general practitioners (GP), or having negative experiences due to the stigma attached with PIED use. Few participants reported disclosing their PIED use to their GP not only because of the concerns that their GP would no longer see them but also because they felt their GP was not knowledgeable about these substances. DISCUSSION AND CONCLUSION: Participants in the study reported no difficulty in accessing health services based on living in a regional area, with their concern focused more upon how they were viewed and treated by service staff. [Dunn M, Henshaw R, Mckay F. H. Do performance and image enhancing drug users in regional Queensland experience difficulty accessing health services? Drug Alcohol Rev 2016;35:377-382].

Does obesity really matter? The impact of BMI on embryo quality and pregnancy outcomes after IVF in women aged ≤38 years.

BACKGROUND: The increasing prevalence of obesity in women of child-bearing age is of growing concern in the health community. Obesity is associated with sub-optimal reproductive performance; therefore, it is understandable that the number of young women with elevated body mass index (BMI) accessing assisted reproductive treatment (ART) is on the rise. Consequently, this study not only assessed the impact of BMI on fertilisation rates, embryo development and freezing during ART in women aged ≤38 years but also determined their subsequent pregnancy and delivery rates. METHODS: Data were retrospectively analysed from all cycles initiated in 2006/2007 for women aged ≤38 years. The BMI categorisations were as follows: normal - 18.5-24.9 kg/m(2) ; overweight - 25-29.9 kg/m(2) ; obese - 30-34.9 kg/m(2) ; morbidly obese class I - 35-39.9 kg/m(2) ; morbidly obese class П -≥40 kg/m(2) . RESULTS: Obese and morbidly obese women required a significantly higher follicle stimulating hormone start dose than normal BMI women; however, they obtained significantly fewer oocytes (P < 0.05). Although BMI did not affect embryo development, morbidly obese class Π women had significantly reduced pregnancy rates compared to normal BMI women (30.5 vs 41.7%, respectively; P < 0.05). Furthermore, increasing BMI was positively correlated to increasing rates of preterm delivery (P < 0.05). Increasing BMI was also positively correlated to increasing delivery rates of singleton term macrosomic offspring (≥4000 g). CONCLUSION: Obesity in women aged≤38 years does not affect embryo development; however, it does reduce clinical pregnancy rates in women with a BMI≥40 and increases rates of preterm labour and delivery of macrosomic offspring.

Paternal body mass index is associated with decreased blastocyst development and reduced live birth rates following assisted reproductive technology.

OBJECTIVE: To determine the relationship between paternal body mass index (BMI), embryo development and pregnancy, and live birth outcomes after assisted reproductive technology (ART). DESIGN: Retrospective analysis of ART cycles. SETTING: Major assisted reproduction center. PATIENT(S): Three hundred five couples undergoing ART in a private fertility clinic. INTERVENTION(S): No intervention was undertaken in patients involved in this study. MAIN OUTCOME MEASURE(S): Live birth outcomes and clinical pregnancy rates. RESULT(S): No significant relationship between paternal BMI and early embryo development was found. However, increased paternal BMI was associated with decreased blastocyst development, clinical pregnancy rates and live birth outcomes. CONCLUSION(S): To our knowledge, this is the first report linking increased paternal BMI and clinical pregnancy and live birth rates after ART treatment. Further work to elucidate the mechanisms involved is required.

Day 4 embryo selection is equal to Day 5 using a new embryo scoring system validated in single embryo transfers.

BACKGROUND: Single embryo transfers (SETs) require the most viable embryo from a cohort to be selected. Day 4 embryos may provide a selection advantage similar to blastocyst transfer as embryos are replaced post-embryonic genome activation and into the uterus where they would normally reside. However, there is currently no adequate morphological system to assess Day 4 embryos. Therefore, we developed an assessment system for Day 4 embryos and retrospectively assessed Day 4 SET success rates compared with Day 5 SETs. METHODS: Embryos (n = 996 after IVF or ICSI) were assessed on Day 4 of development, prior to implementing Day 4 embryo transfers, to obtain a descriptive range of embryo morphologies observed at this time point. A morphological scoring system was developed from this. All patients having an SET after extended culture (Day 4, n = 124 or Day 5, n = 193), at Repromed, Adelaide, Australia, during June 2006-January 2007 were analysed for pregnancy outcome. Ongoing pregnancy was determined by fetal cardiac activity at 6-8 weeks after oocyte collection. RESULTS: Day 4 and 5 SETs resulted in similar ongoing pregnancy rates of 38.7% and 32.1%, respectively. CONCLUSIONS: A Day 4 scoring system was successfully developed and implemented. Day 4 SETs were found to be a viable option or alternative to Day 5 SETs with no difference in pregnancy rates.

A retrospective cohort study comparing microwave endometrial ablation with levonorgestrel-releasing intrauterine device in the management of heavy menstrual bleeding.

OBJECTIVE: To compare microwave endometrial ablation (MEA) with a levonorgestrel-releasing intrauterine device (Mirena) in the management of heavy menstrual bleeding. DESIGN: A retrospective cohort study SAMPLE: Thirty-nine women were treated with MEA and 23 women with Mirena, in the South East Regional Health Service of South Australia during 1998 to 2001; the mean duration of follow-up was 14.6 months. MAIN OUTCOME MEASURES: Primary measures included acceptability of the treatment process, effectiveness of the treatment, and satisfaction with outcomes. Secondary measures included side effects, complications and quality of life (using the SF-36). RESULTS: Acceptability of the treatment process and satisfaction with outcomes was very high for both procedures. Each treatment led to a statistically significant reduction in menstrual bleeding (p < 0.0001) and dysmenorrhoea scores (p < 0.002). CONCLUSIONS: There were no statistical differences between the two treatments for any of the primary or secondary outcome measures assessed. The treatments seem equally effective in the management of heavy menstrual loss.