20 research outputs found
High Hemocyte Load Is Associated with Increased Resistance against Parasitoids in Drosophila suzukii, a Relative of D. melanogaster
Among the most common parasites of Drosophila in nature are parasitoid wasps, which lay their eggs in fly larvae and pupae. D. melanogaster larvae can mount a cellular immune response against wasp eggs, but female wasps inject venom along with their eggs to block this immune response. Genetic variation in flies for immune resistance against wasps and genetic variation in wasps for virulence against flies largely determines the outcome of any fly-wasp interaction. Interestingly, up to 90% of the variation in fly resistance against wasp parasitism has been linked to a very simple mechanism: flies with increased constitutive blood cell (hemocyte) production are more resistant. However, this relationship has not been tested for Drosophila hosts outside of the melanogaster subgroup, nor has it been tested across a diversity of parasitoid wasp species and strains. We compared hemocyte levels in two fly species from different subgroups, D. melanogaster and D. suzukii, and found that D. suzukii constitutively produces up to five times more hemocytes than D. melanogaster. Using a panel of 24 parasitoid wasp strains representing fifteen species, four families, and multiple virulence strategies, we found that D. suzukii was significantly more resistant to wasp parasitism than D. melanogaster. Thus, our data suggest that the relationship between hemocyte production and wasp resistance is general. However, at least one sympatric wasp species was a highly successful infector of D. suzukii, suggesting specialists can overcome the general resistance afforded to hosts by excessive hemocyte production. Given that D. suzukii is an emerging agricultural pest, identification of the few parasitoid wasps that successfully infect D. suzukii may have value for biocontrol
Use of smoking cessation pharmacotherapies during pregnancy is not associated with increased risk of adverse pregnancy outcomes: A population-based cohort study
Background: Varenicline, bupropion and nicotine replacement therapy (NRT) are three effective pharmacotherapies for smoking cessation, but data about their safety in pregnancy are limited. We assessed the risk of adverse perinatal outcomes and major congenital anomalies associated with the use of these therapies in pregnancy in Australia. Methods: Perinatal data for 1,017,731 deliveries (2004 to 2012) in New South Wales and Western Australia were linked to pharmaceutical dispensing, hospital admission and death records. We identified 97,875 women who smoked during pregnancy; of those, 233, 330 and 1057 were exposed to bupropion, NRT and varenicline in pregnancy, respectively. Propensity scores were used to match exposed women to those who were unexposed to any smoking therapy (1:10 ratio). Propensity scores and gestational age at exposure were used to match varenicline-exposed to NRT-exposed women (1:1 ratio). Time-dependent Cox proportional hazards models estimated hazard ratios (HR) with 95% confidence intervals (95% CI) for any adverse perinatal event (a composite of 10 unfavourable maternal and neonatal outcomes) and any major congenital anomaly. Results: The risk of any adverse perinatal event was not significantly different between bupropion-exposed and unexposed women (39.2% versus 39.3%, HR 0.93, 95% CI 0.73-1.19) and between NRT-exposed and unexposed women (44.8% vs 46.3%, HR 1.02, 95% CI 0.84-1.23), but it was significantly lower in women exposed to varenicline (36.9% vs 40.1%, HR 0.86, 95% CI 0.77-0.97). Varenicline-exposed infants were less likely than unexposed infants to be born premature (6.5% vs 8.9%, HR 0.72, 95% CI 0.56-0.92), be small for gestational age (11.4% vs 15.4%, HR 0.68, 95% CI 0.56-0.83) and have severe neonatal complications (6.6% vs 8.2%, HR 0.74, 95% CI 0.57-0.96). Among infants exposed to varenicline in the first trimester, 2.9% had a major congenital anomaly (3.5% in unexposed infants, HR 0.91, 95% CI 0.72-1.15). Varenicline-exposed women were less likely than NRT-exposed women to have an adverse perinatal event (38.7% vs 51.4%, HR 0.58, 95% CI 0.33-1.05). Conclusions: Pregnancy exposure to smoking cessation pharmacotherapies does not appear to be associated with an increased risk of adverse birth outcomes. Lower risk of adverse birth outcomes in varenicline-exposed pregnancies is inconsistent with recommendations that NRT be used in preference to varenicline
Dentists, antibiotics and Clostridium difficile-associated disease
Dentists prescribe significant volumes of antimicrobial drugs within primary care settings. There is good evidence that many of the prescriptions are not justified by current clinical guidance and that that there is considerable misuse of these drugs in dentistry. One of the risks associated with antibiotic administration is Clostridium difficile-associated disease (CDAD), an entity of which many healthcare workers, including dentists, have little knowledge or understanding. This review seeks to identify the extent and nature of the problem and provides an up to date summary of current views on CDAD, with particular reference to community acquired disease. As for all healthcare workers, scrupulous attention to standard infection control procedures and reducing inappropriate antibiotic prescribing are essential to reduce the risks of CDAD, prevent emergence of further resistant strains of microorganisms and maintain the value of the arsenal of antibiotics currently available to us
The association between moral disengagement, psychological distress, resistive self-regulatory efficacy and alcohol and cannabis use among adolescents in Sydney, Australia
Objective: The current study aimed to: (i) examine the estimated proportion of young Australian’s using alcohol and cannabis, and (ii) investigate a number of individual risk factors associated with use. Method: A total of 1022 students aged between 12 and 15 years (86% male) were recruited from ten independent schools in Sydney, Australia. All participants completed a questionnaire measuring demographics, levels of moral disengagement, psychological distress, self-regulatory efficacy to resist peer pressure to engage in transgressive behaviour, and alcohol and cannabis use. Results: Approximately 85% of participants reported having ever tried alcohol in their life, 31% reported having ever had a full serve of alcohol in their life, 9% reported binge drinking in the past 3 months, and 4% reported having ever tried cannabis in their life. Logistic regression analyses revealed higher moral disengagement and lower resistive selfregulatory efficacy were independent predictors of ever having a full serve of alcohol, binge drinking in the past 3 months and ever trying cannabis. Psychological distress was not associated with alcohol or cannabis use. Conclusions: A better understanding of the factors associated with early alcohol and cannabis use may help identify groups who have difficulties controlling use and aid the development of targeted prevention strategies for reducing use and related harms