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Several grass and broadleaf weed species around the world have evolved multiple-herbicide resistance at alarmingly increasing rates. Research on the biochemical and molecular resistance mechanisms of multiple-resistant weed populations indicate a prevalence of herbicide metabolism catalyzed by enzyme systems such as cytochrome P450 monooxygenases and glutathione S-transferases and, to a lesser extent, by glucosyl transferases. A symposium was conducted to gain an understanding of the current state of research on metabolic resistance mechanisms in weed species that pose major management problems around the world. These topics, as well as future directions of investigations that were identified in the symposium, are summarized herein. In addition, the latest information on selected topics such as the role of safeners in inducing crop tolerance to herbicides, selectivity to clomazone, glyphosate metabolism in crops and weeds, and bioactivation of natural molecules is reviewed.
Neurodevelopmental impairment is increasingly recognised as a potentially disabling outcome of CHD and formal evaluation is recommended for high-risk patients. However, data are lacking regarding the proportion of eligible children who actually receive neurodevelopmental evaluation, and barriers to follow-up are unclear. We examined the prevalence and risk factors associated with failure to attend neurodevelopmental follow-up clinic after infant cardiac surgery.
Survivors of infant (<1 year) cardiac surgery at our institution (4/2011-3/2014) were included. Socio-demographic and clinical characteristics were evaluated in neurodevelopmental clinic attendees and non-attendees in univariate and multivariable analyses.
A total of 552 patients were included; median age at surgery was 2.4 months, 15% were premature, and 80% had moderate–severe CHD. Only 17% returned for neurodevelopmental evaluation, with a median age of 12.4 months. In univariate analysis, non-attendees were older at surgery, had lower surgical complexity, fewer non-cardiac anomalies, shorter hospital stay, and lived farther from the surgical center. Non-attendee families had lower income, and fewer were college graduates or had private insurance. In multivariable analysis, lack of private insurance remained independently associated with non-attendance (adjusted odds ratio 1.85, p=0.01), with a trend towards significance for distance from surgical center (adjusted odds ratio 2.86, p=0.054 for ⩾200 miles).
The majority of infants with CHD at high risk for neurodevelopmental dysfunction evaluated in this study are not receiving important neurodevelopmental evaluation. Efforts to remove financial/insurance barriers, increase access to neurodevelopmental clinics, and better delineate other barriers to receipt of neurodevelopmental evaluation are needed.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
Large volumes of data and multiple computing platforms are now universal components of paediatric cardiovascular medicine, but are in a constant state of evolution. Often, multiple sets of related data reside in disconnected “silos”, resulting in clinical, administrative, and research activities that may be duplicative, inefficient, and at times inaccurate. Comprehensive and integrated data solutions are needed to facilitate these activities across congenital heart centres. We describe methodology, key considerations, successful use cases, and lessons learnt in developing an integrated data platform across our congenital heart centre.
Fontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients.
Methods and results
This study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman’s Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6–33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (−0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (−0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63–0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2 versus lower-risk group=2.96 L/minute/m2, (p<0.01)].
Higher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.
We analyzed birth order differences in means and variances of height and body mass index (BMI) in monozygotic (MZ) and dizygotic (DZ) twins from infancy to old age. The data were derived from the international CODATwins database. The total number of height and BMI measures from 0.5 to 79.5 years of age was 397,466. As expected, first-born twins had greater birth weight than second-born twins. With respect to height, first-born twins were slightly taller than second-born twins in childhood. After adjusting the results for birth weight, the birth order differences decreased and were no longer statistically significant. First-born twins had greater BMI than the second-born twins over childhood and adolescence. After adjusting the results for birth weight, birth order was still associated with BMI until 12 years of age. No interaction effect between birth order and zygosity was found. Only limited evidence was found that birth order influenced variances of height or BMI. The results were similar among boys and girls and also in MZ and DZ twins. Overall, the differences in height and BMI between first- and second-born twins were modest even in early childhood, while adjustment for birth weight reduced the birth order differences but did not remove them for BMI.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
Background: There is strong evidence that clinical outcomes are improved for stroke patients admitted to specialized Stroke Units. The Toronto Western Hospital (TWH) created a Neurovascular Unit (NVU) using resources from General Internal Medicine, Neurology, and Neurosurgery for patients with stroke and acute neurovascular conditions. Under resource-constrained conditions, the operational and economic impacts of the Neurovascular Unit were unknown. Methods: Retrospective patient-level data was studied from two years prior and one year post NVU implementation. Descriptive statistical analysis and non-parametric testing were conducted on the acute length of stay (LOS), alternate level of care LOS, total cost per bed-day and per visit, and patient flow within each medical service and hospital wide. Results: The median acute LOS per hospitalization for NVU-eligible patients decreased significantly (p=0.001). For Neurology patients, mean acute LOS decreased from 9.1 days pre-Neurovascular Unit to 7.6 days post and median acute LOS decreased from 6 to 5 days (p=0.002); however, mean alternate level of care LOS per visit more than doubled (from 1.6 to 4.1 days, p=0.001). For the Neurology service, the mean cost per visit decreased by $945, representing a 5% reduction (p=0.042) and the mean cost per bed-day decreased by $233, or 12.5% (p=0.026). Hospital wide, a saving of over C$450 000 was achieved. Conclusions: During the first year of operation, the NVU at TWH achieved decreased acute LOS per visit and lowered the total hospitalization cost per year for NVU-eligible patients. Addressing the issue of increased alternate level of care LOS could result in additional efficiencies.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
Self-report questionnaires are frequently used in clinical and epidemiologic studies to assess post-traumatic stress disorder (PTSD). A number of studies have evaluated these scales relative to clinician administered structured interviews; however, there has been no formal evaluation of their performance relative to non-clinician administered epidemiologic assessments such as the Composite International Diagnostic Interview (CIDI). We examined the diagnostic performance of two self-report PTSD scales, the PTSD checklist (PCL) and the Vietnam Era Twin Registry (VET-R) PTSD scale, compared to the CIDI.
Data were derived from a large epidemiologic follow-up study of PTSD in 5141 Vietnam Era Veterans. Measures included the PCL, VET-R PTSD scale and CIDI. For both the PCL and VET-R PTSD scale, ROC curves, areas under the curve (AUC), sensitivity, specificity, % correctly classified, likelihood ratios, predictive values and quality estimates were generated based on the CIDI PTSD diagnosis.
For the PCL and VET-R PTSD scale the AUCs were 89.0 and 87.7%, respectively. Optimal PCL cutpoints varied from the 31–33 range (when considering sensitivity and specificity) to the 36–56 range (when considering quality estimates). Similar variations were found for the VET-R PTSD, ranging from 31 (when considering sensitivity and specificity) to the 37–42 range (when considering quality estimates).
The PCL and VET-R PTSD scale performed similarly using a CIDI PTSD diagnosis as the criterion. There was a range of acceptable cutpoints, depending on the metric used, but most metrics suggested a lower PCL cutpoint than in previous studies in Veteran populations.
Two-dimensional crystals are an important class of materials for novel physics, chemistry, and engineering. Germanane (GeH), the germanium-based analogue of graphane (CH), is of particular interest due to its direct band gap and spin–orbit coupling. Here, we report the successful co-deposition growth of CaGe2 films on Ge(111) substrates by molecular beam epitaxy and their subsequent conversion to germanane by immersion in hydrochloric acid. We find that the growth of CaGe2 occurs within an adsorption-limited growth regime, which ensures stoichiometry of the film. We utilize in situ reflection high energy electron diffraction (RHEED) to explore the growth temperature window and find the best RHEED patterns at 750 °C. Finally, the CaGe2 films are immersed in hydrochloric acid to convert the films to germanane. Auger electron spectroscopy of the resulting film indicates the removal of Ca, and RHEED patterns indicate a single-crystal film with an in-plane orientation dictated by the underlying Ge(111) substrate. X-ray diffraction and Raman spectroscopy indicate that the resulting films are indeed germanane. Ex situ atomic force microscopy shows that the grain size of the germanane is on the order of a few micrometers, being primarily limited by terraces induced by the miscut of the Ge substrate. Thus, optimization of the substrate could lead to the long-term goal of large area germanane films.
It is paramount to understand the epidemiology of chronic hepatitis B to inform national policies on vaccination and screening/testing as well as cost-effectiveness studies. However, information on the national (Scottish) prevalence of chronic hepatitis B by ethnic group is lacking. To estimate the number of people with chronic hepatitis B in Scotland in 2009 by ethnicity, gender and age, the test data from virology laboratories in the four largest cities in Scotland were combined with estimates of the ethnic distribution of the Scottish population. Ethnicity in both the test data and the Scottish population was derived using a name-based ethnicity classification software (OnoMAP; Publicprofiler Ltd, UK). For 2009, we estimated 8720 [95% confidence interval (CI) 7490–10 230] people aged ⩾15 years were living with chronic hepatitis B infection in Scotland. This corresponds to 0·2% (95% CI 0·17–0·24) of the Scottish population aged ⩾15 years. Although East and South Asians make up a small proportion of the Scottish population, they make up 44% of the infected population. In addition, 75% of those infected were aged 15–44 years with almost 60% male. This study quantifies for the first time on a national level the burden of chronic hepatitis B infection by ethnicity, gender and age. It confirms the importance of promoting and targeting ethnic minority groups for hepatitis B testing.
Earlier clinical studies have suggested consistent differences between anxious and non-anxious depression. The aim of this study was to compare parental pathology, personality and symptom characteristics in three groups of probands from the general population: depression with and without generalized anxiety disorder (GAD) and with other anxiety disorders. Because patients without GAD may have experienced anxious symptoms for up to 5 months, we also considered GAD with a duration of only 1 month to produce a group of depressions largely unaffected by anxiety.
Depressive and anxiety disorders were assessed in a 10-year prospective longitudinal community and family study using the DSM-IV/M-CIDI. Regression analyses were used to reveal associations between these variables and with personality using two durations of GAD: 6 months (GAD-6) and 1 month (GAD-1).
Non-anxious depressives had fewer and less severe depressive symptoms, and higher odds for parents with depression alone, whereas those with anxious depression were associated with higher harm avoidance and had parents with a wider range of disorders, including mania.
Anxious depression is a more severe form of depression than the non-anxious form; this is true even when the symptoms required for an anxiety diagnosis are ignored. Patients with non-anxious depression are different from those with anxious depression in terms of illness severity, family pathology and personality. The association between major depression and bipolar disorder is seen only in anxious forms of depression. Improved knowledge on different forms of depression may provide clues to their differential aetiology, and guide research into the types of treatment that are best suited to each form.