Inhibition of Phytophthora parasitica and P. capsici by Silver Nanoparticles Synthesized Using Aqueous Extract of Artemisia absinthium

Application of nanoparticles for controlling plant pathogens is a rapidly emerging area in plant disease management, and nanoparticles synthesis methods that are economical and ecofriendly are extensively investigated. In this project, we investigated the potential of silver nanoparticles (AgNPs) synthesized with aqueous extract of Artemisia absinthium against several Phytophthora spp., which cause many economically important crop diseases. In in vitro dose-response tests conducted in microtiter plates, 10 µg ml⁻¹ of AgNPs inhibited mycelial growth of P. parasitica, P. infestans, P. palmivora, P. cinnamomi, P. tropicalis, P. capsici, and P. katsurae. Detailed in vitro dose-response analyses conducted with P. parasitica and P. capsici revealed that AgNPs synthesized with A. absinthium extract were highly potent (IC50: 2.1 to 8.3 µg ml⁻¹) and efficacious (100%) in inhibiting mycelial growth, zoospore germination, germ tube elongation, and zoospore production. Interestingly, AgNP treatment accelerated encystment of zoospores. Consistent with in vitro results, in planta experiments conducted in a greenhouse revealed that AgNP treatments prevented Phytophthora infection and improved plant survival. Moreover, AgNP in in planta experiments did not produce any adverse effects on plant growth. These investigations provide a simple and economical method for controlling Phytophthora with AgNP without affecting normal plant physiology.

Perceptions of pesticides exposure risks by operators, workers, residents and bystanders in Greece, Italy and the UK

The EU Directive on the sustainable use of pesticides (EU128/2009/EC) requires European Member States to develop training activities targeting occupational exposure to pesticides, and communication material aimed at residents and bystanders. Risk perceptions, knowledge and attitudes associated with passive and occupational exposure to pesticide potentially influence the extent to which different stakeholders adopt self-protective behaviour. A methodology for assessing the link between attitudes, adoption of self-protective behaviours and exposure was developed and tested. A survey was implemented in the Greece, Italy and the UK, and targeted stakeholders associated with pesticide exposure linked to orchards, greenhouse crops and arable crops respectively. The results indicated that the adoption of protective measures is low for residents and bystanders, with the exception of residents in Greece, when compared to operators and workers, who tend to follow recommended safety practices. A regression analysis was used to examine the factors affecting the probability of adopting protective measures as well the as the level of exposure in the case of operators and workers where data are available. The results indicate that the likelihood of engaging in self-protective behaviour is not significantly affected by perceptions of own health being affected by pesticides for residents and bystanders. However, operators who perceive that their heath has been negatively affected by the use of pesticides are found to be more likely to adopt self-protective behaviours. Gender and country differences, in perceptions, attitudes and self-protection are also observed. Recommendations for improved communication, in particular for vulnerable groups, are provided.

Trading between healthy food, alcohol and physical activity behaviours

BACKGROUND

While recent lifestyle studies have explored the role that food, alcohol or physical activity have on health and wellbeing, few have explored the interplay between these behaviours and the impact this has on a healthy lifestyle. Given the long term health advantages associated with leading healthier lifestyles, this study seeks to: 1) explore the interplay between the food, alcohol and physical activity behaviours of young adults (aged 19-26 years) in the North East of England; 2) explore the trade-offs young adults make between their food, alcohol and physical activity behaviours; and 3) recognise the positive and negative associations between the three behaviours.

METHODS

Qualitative self-reported lifestyle diaries and in-depth interviews were conducted with 50 young adults from the North East of England between February and June 2008. Qualitative thematic analysis was undertaken using Nvivo QSR software, and diary coding using Windiets software.

RESULTS

Young adults who attempt to achieve a 'healthy lifestyle' make trade-offs between the food and alcohol they consume, and the amounts of physical activity they undertake. There are negative reasons and positive consequences associated with these trade-offs. Young adults recognise the consequences of their behaviours and as a result are prepared to undertake healthy behaviours to compensate for unhealthy behaviours. They prefer certain strategies to promote healthier behaviours over others, in particular those that relate to personalised advice and support, more affordable ways to be healthier and easily-accessed advice from a range of media sources.

CONCLUSIONS

Young adults seek to compensate unhealthy behaviours (e.g. binge drinking) with healthy behaviours (e.g. physical activity). Creative solutions may be required to tackle these trade-offs and promote a balance across the food, alcohol and physical activity behaviours of this age group. Solutions that may be effective with this age group include environmental changes (e.g. green spaces and increasing the price of alcohol) designed to encourage and facilitate young people making healthier choices and improving their access to, and lowering the price of, healthy food products. Solutions must recognise these trade-offs and in particular, the strong reluctance of young adults to alter their higher-than-recommended levels of alcohol consumption.

Therapeutic drug monitoring of atazanavir/ritonavir in pregnancy

OBJECTIVES

Pregnant women experience physiological changes during pregnancy that can have a significant impact on antiretroviral pharmacokinetics. Ensuring optimal plasma concentrations of antiretrovirals is essential for maternal health and to minimize the risk of vertical transmission. Here we describe atazanavir/ritonavir (ATV/r) plasma concentrations in a cohort of pregnant women undergoing routine therapeutic drug monitoring (TDM).

METHODS

Pregnant HIV-positive women received ATV/r as part of their routine pre-natal care. Demographic and clinical data were collected. ATV plasma concentrations ([ATV]) were determined in the first (T1), second (T2) and third (T3) trimesters and at postpartum (PP) using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

From January 2007, 44 women (37 black African) were enrolled in the study. All received ATV/r at a dose of 300/100 mg once a day. Twenty-four had received antiretroviral therapy (ART) prior to pregnancy, and 20 initiated ATV/r in pregnancy. At the time nearest to delivery, 36 patients had undetectable plasma viral loads. [ATV] values were determined in 11 (T1), 25 (T2), 34 (T3) and 28 (PP) patients. [ATV] at 24 hours post-dose (C24) values significantly lower at T2/T3 relative to PP.

CONCLUSIONS

This study was carried out in one of the larger cohorts of women undergoing TDM for ATV in pregnancy. Lower [ATV] values were seen in T2/T3 compared with T1/PP. However, [ATV] were not associated with a lack of virologic suppression at delivery. Nonetheless, careful monitoring of women in pregnancy is required, and dose adjustment of ATV to 400 mg may be an option.

Universal antenatal screening for hepatitis C

The aims of this study were to pilot universal antenatal HCV screening and to determine the true seroprevalence of HCV infection in an unselected antenatal population. A risk assessment questionnaire for HCV infection was applied to all women booking for antenatal care over a 1-year period. In addition the prevalence of anti-HCV antibody positive serology in this population was determined. Over the course of the year, 9121 women booked for antenatal care at the Rotunda and 8976 women agreed to take part in the study, representing an uptake of 98.4%. 78 (0.9%) women were diagnosed as anti-HCV positive, the majority of whom were Irish (60.3%) or from Eastern Europe (24.4%). 73% of anti-HCV positive women reported one or more known risk factor with tattooing and a history of drug abuse the most commonly reported. 27% (n = 21) of anti-HCV positive women had no identifiable risk factors. Due to selective screening, seroprevalence of HCV is impossible to accurately calculate. However the universal screening applied here and the high uptake of testing has allowed the prevalence of anti-HCV among our antenatal population to be calculated at 0.9%. A significant proportion (27%) of anti-HCV positive women in this study reported no epidemiological risk factors at the time

First Report of Elm Canker Caused by Pestalotiopsis mangiferae in the United States

Chinese elm (Ulmus parvifolia Jacq.) is native to China, Korea, and Japan and was introduced to the U.S. to replace the American elm, which is highly susceptible to Dutch elm disease. Cultivar Emmer II trademark Allee elm (or Allee elm) is preferred by nurseries for its rich green foliage and beauty of bark. In the summer of 2011, a new disease was observed on Allee elm at a tree farm in FL. Approximately 1% of elms in the same farm and in residential areas in central Florida had similar canker-like symptoms consisting of tan to orange patches of decomposed and loose bark. These symptoms were observed on the main trunks often extending into branches of affected trees. Cankered sections of the trunk were often several feet in length and penetrated the wood to a depth just under the bark into the phloem. To isolate the causal organism, cankers were gathered from 7 trees and tissues from the margin of 1 to 3 cankers per tree were surface sterilized in 1% sodium hypochlorite, plated on PDA, and incubated at 22°C under a 16-h/8-h light/dark cycle for 7 days. Colonies displayed white, fluffy mycelium with sporadic black acervuli containing aggregated conidia. Conidia were 5-celled with two or more apical appendages or hairs; the three central cells were dark brown and the two outer cells were hyaline (1). Based on conidial morphology, these isolates were putatively identified as Pestalotiopsis spp. To identify the species, the rDNA internal transcribed spacer (ITS) region was sequenced for two field isolates (GenBank Accessions JX999998 and JX999999). A BLASTn search in GenBank revealed 100% identity to Pestalotiopsis mangiferae ITS (JX305704.1). To test Koch's postulates, experiments were performed in the field and greenhouse. A mycelial plug of isolate 11-40 was grown on PDA, inoculated on wounded trunk of healthy 18-month-old Allee elms (n = 48) in the field and 7-month-old Allee elms (n = 12) in the greenhouse. Both experiments were set up as a randomized complete block design. The trunk of each tree was wounded with a scalpel to a depth of 5 mm, the wound was inoculated with a 5-mm² agar plug from a 7-day PDA culture, and the inoculated wound was wrapped with grafting tape. Plants that served as negative controls [n = 20 (field experiment) and n = 12 (greenhouse)] were mock-inoculated with a sterile PDA plug without mycelial growth. After 4 to 6 months, symptoms consisting of loose or fallen off bark developed on all pathogen-inoculated trees but not on control trees. Control wounds healed with no expansion beyond the original 5 mm inoculation zone, whereas Pestalotiopsis-inoculated cankers expanded to 3 to 8 cm in each direction in 6 months. Pestalotiopsis (confirmed by conidial morphology and ITS sequencing) was reisolated from pathogen-inoculated trees but not from control trees. These experiments were repeated with similar results at least three times, each consisting of 15 replications (greenhouse) and 12 replications (field) with additional Pestalotiopsis isolates. Many other Pestaliopsis spp. have been reported on other shade trees through the U.S. and the world. To our knowledge, this is the first report of P. mangiferae on an Ulmus species in the U.S. and the world. Since elm canker mainly affects the trunk, a featured characteristic of the Allee elm, it can potentially result in economic loss to the ornamental industry. References: (1) Y. Ko et al. Plant Dis. 91:1684, 2007. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

Single port laparoscopic subtotal colectomy and ileostomy in an adolescent with ulcerative colitis

INTRODUCTION

Single port laparoscopic surgery has been increasingly used for complex surgical procedures. To our knowledge, this is the first published report of a single port laparoscopic subtotal colectomy and ileostomy in an adolescent patient with ulcerative colitis.

CASE REPORT

A 13-year old female patient with ulcerative colitis resistant to maximal medical therapy underwent a single port laparoscopic subtotal colectomy and ileostomy. Both the procedure and the postoperative recovery were uneventful and the patient was discharged home on the sixth postoperative day. Follow-up at 3 and 8 weeks after surgery identified no early complications with a 4 kg weight gain.

DISCUSSION

Single port laparoscopic surgery is feasible in the adolescent population if there is appropriate surgical expertise and strict patient selection.

Evaluation of the clinical hour requirement and attainment of core clinical competencies by nurse practitioner students

PURPOSE

The purpose of this study was to analyze the national practice of fulfilling 500 clinical hours as a requirement for graduation from nurse practitioner (NP) programs at the master's level and to compare this standard to a comprehensive approach of evaluating attainment of clinical competencies.

DATA SOURCES

The National Organization of NP Faculties (NONPF) and specialty accreditation bodies publications were used for references to clinical hour and core competency requirements for graduation from NP programs. Data from one university from student documentation on a commercial electronic tracking system were also analyzed.

CONCLUSIONS

Data analysis revealed that the 500 clinical hours correlated to populations, skills performed, required levels of decision making, and expected diagnoses. However, assurance that these clinical hour requirements translated to exposure to all core competencies for entry into practice could not be established.

IMPLICATIONS FOR PRACTICE

A more comprehensive approach to the evaluation of student core competencies by implementing one or more performance-based assessments, such as case-based evaluations, simulations, or objective structured clinical examinations (OSCEs), as a strategic part of NP evaluation prior to graduation is proposed. This change is viewed as critical to the continued success of NP programs as master's level education transitions to direct BS to DNP educational preparation for advanced nursing practice.

Towards the genetic architecture of seed lipid biosynthesis and accumulation in Arabidopsis thaliana

We report the quantitative genetic analysis of seed oil quality and quantity in six Arabidopsis thaliana recombinant inbred populations, in which the parent accessions were from diverse geographical origins, and were selected on the basis of variation for seed oil content and lipid composition. Although most of the biochemical steps involved in lipid biosynthesis are known and the key genes have been identified, the regulation of the processes that results in the final oil composition and total amount is not understood. By using physically anchored markers it was possible to compare results across populations. A total of 219 quantitative trait loci (QTLs) were identified, of which 81 were significant at P<0.001. Some of these colocalise with QTLs identified previously, but many novel QTLs were also identified. The results highlight the importance of studying traits in multiple populations, which will lead to a better understanding of the contribution that natural variation makes to the genetic architecture of a phenotype.

Laparoscopic adult colorectal surgeon and adolescents with inflammatory bowel disease: a safe combination?

INTRODUCTION

A multidisciplinary tertiary service for adolescents with inflammatory bowel disease (IBD) was commenced in April 2008, aiming to provide specialist treatment for adolescent patients and bridge the gap between existing paediatric and adult surgical services. A single laparoscopic colorectal surgeon who normally treats adult patients has been part of the multidisciplinary team since its inception.

AIM

To analyse outcomes for those patients requiring surgical resection during the first 2 years of service.

METHODS

In this service evaluation study, all data for patients undergoing surgery from 1 April 2008 to 31 March 2010 were prospectively collected on a dedicated electronic database.

RESULTS

Nineteen patients underwent surgical resection (15 laparoscopic and four open) over the 2-year period. Median patient age was 15 years (range 11-16), and 14 patients were female. Of the 15 laparoscopic resections, eight were subtotal colectomy and ileostomy and seven ileocaecal resection/right hemicolectomy. There was one (6.7%) conversion due to a pericolic abscess. There were four planned open cases, including two subtotal colectomy and ileostomy and two small bowel resections. Median operating time was 150 and 172.5 min in the open and laparoscopic groups respectively. Median length of stay was 6 days (range 3-16) in the laparoscopic group, and 8 days (range 5-13) in the open group. There were three (15.8%) post-operative complications, one (5.3%) readmission within 30 days and no mortality.

CONCLUSION

This study suggests that an adult colorectal surgeon can provide a safe and effective service for adolescents with IBD, including the provision of laparoscopic resection in this challenging patient group.

How can warren destruction by ripping control European wild rabbits (Oryctolagus cuniculus) on large properties in the Australian arid zone?

Context For over 100 years, control efforts have been unable to stop rabbits causing damage to cattle production and native plants and animals on large properties in arid parts of Australia. Warren destruction by ripping has shown promise, but doubts about long-term success and the perceived expense of treating vast areas have led to this technique not being commonly used. Aims This study measured the long-term reduction in rabbit activity and calculated the potential cost saving associated with treating just the areas where rabbits are believed to survive drought. We also considered whether ripping should be used in a full-scale rabbit control program on a property where rabbits have been exceptionally resilient to the influence of biological and other control measures. Methods Rabbits were counted along spotlight transects before warrens were ripped and during the two years after ripping, in treated and untreated plots. Rabbit activity was recorded to determine the immediate and long-term impact of ripping, up to seven years after treatment. The costs of ripping warrens within different distances from drought refuge areas were calculated. Key results Destroying rabbit warrens by ripping caused an immediate reduction in rabbit activity and there were still 98% fewer rabbits counted by spotlight in ripped plots five months after ripping. Seven years after ripping no active warrens were found in ripped plots, whereas 57% of warrens in unripped plots showed signs of rabbit activity. The cost of ripping only the areas where rabbits were likely to seek refuge from drought was calculated to be less than 4% of the cost of ripping all warrens on the property. Conclusions Destroying rabbit warrens by ripping is a very effective way of reducing rabbit numbers on large properties in arid Australia. Ripping should commence in areas used by rabbits to survive drought. It is possible that no further ripping will be required. Implications Strategic destruction of warrens in drought refuge areas could provide an alternative to biological control for managing rabbits on large properties in the Australian arid zone.