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101.
Tom J. B. de Man Jason E. Stajich Christian P. Kubicek Clotilde Teiling Komal Chenthamara Lea Atanasova Irina S. Druzhinina Natasha Levenkova Stephanie S. L. Birnbaum Seth M. Barribeau Brooke A. Bozick Garret Suen Cameron R. Currie Nicole M. Gerardo 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(13):3567-3572
Many microorganisms with specialized lifestyles have reduced genomes. This is best understood in beneficial bacterial symbioses, where partner fidelity facilitates loss of genes necessary for living independently. Specialized microbial pathogens may also exhibit gene loss relative to generalists. Here, we demonstrate that Escovopsis weberi, a fungal parasite of the crops of fungus-growing ants, has a reduced genome in terms of both size and gene content relative to closely related but less specialized fungi. Although primary metabolism genes have been retained, the E. weberi genome is depleted in carbohydrate active enzymes, which is consistent with reliance on a host with these functions. E. weberi has also lost genes considered necessary for sexual reproduction. Contrasting these losses, the genome encodes unique secondary metabolite biosynthesis clusters, some of which include genes that exhibit up-regulated expression during host attack. Thus, the specialized nature of the interaction between Escovopsis and ant agriculture is reflected in the parasite’s genome.The highly evolved agricultural lifestyle of leaf-cutting ants has attracted particular attention because these ants cultivate a symbiotic fungus that serves as their major food source. These ants cut leaves, preprocess them into small pieces, and feed them to the cultivated fungus (1). The capacity of the cultivated fungus to break down plant material gives ant agriculturalists access to the vast nutrient stores locked within neotropical plants (Fig. 1A) (2–5). The symbiosis between fungus-growing ants and their cultivated fungi has persisted for at least 50 million years (6).Open in a separate windowFig. 1.Escovopsis weberi, a specialized mycoparasite of the fungus-growing ant symbiosis, has a small genome compared with other Pezizomycotina fungi. (A) Both fungus-growing ants and the mycoparasite E. weberi use the ants’ cultivated fungi as their primary food source. The ability of the cultivated fungi to efficiently break down plant material gives both consumers access to the biomass of neotropical plants. (B) Size and protein-coding gene content of genomes of diverse fungi in the Pezizomycotina. Bayesian phylogeny estimated using partial amino acid alignments of three genes (Rpb1, Rpb2, ef1-α). All posterior probabilities are greater than 0.95. Phylogeny is rooted with Sacchormyces cervesiae (not shown). (C) Relationship between genome size and gene content. A list of genomes included in this panel is in SI Appendix, Table S1.Like human agriculture, ant agriculture is hampered by disease. The ants’ fungal crops are attacked and consumed by fungal parasites of the genus Escovopsis (Ascomycota, Pezizomycotina: anamorphic Hypocreales) (Fig. 1A) (7), which have evolved in association with the ants and their cultivated fungi (8). Escovopsis infection can have detrimental impacts on garden health and, consequently, on the survival of ant colonies (9, 10). Such mycoparasitism, the phenomenon whereby one fungus is parasitic on another fungus, is rare. It is most well-known for species from the genus Trichoderma, some of which are used as biocontrol agents for fungal diseases and others of which attack human-cultivated fungi (11–13). In contrast to Trichoderma species, however, Escovopsis species grow poorly in their hosts’ absence (SI Appendix, Figs. S1 and S2).Escovopsis species have never been isolated outside of fungus-growing ant colonies, and different strains of Escovopsis are capable of attacking the fungi grown by different fungus-growing ant species (8, 14, 15). The long-term, specialized evolutionary history of the association between Escovopsis and their hosts provides a unique venue to explore the consequences of host specialization on pathogen genome evolution. Here, we assemble and annotate the genome of a strain of Escovopsis weberi. Consistent with expectations under an evolutionary transition toward using a narrow host range, and similar to many other specialized, host-associated microbes (16, 17), E. weberi exhibits gene loss. Contrasting other fungal pathogens, the large genomes of which are expanded with genetic elements that influence host adaptation (18), the genome size of Escovopsis is small compared with those of its closest sequenced relatives. 相似文献
102.
Patterns and costs of hospital care for coronary heart disease related and not related to diabetes 总被引:7,自引:0,他引:7
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Objective—To describe the epidemiology and costs of coronary heart disease (CHD) requiring hospital admission, with particular reference to diabetes.
Setting—The former South Glamorgan Health Authority, South Wales.
Methods—Routine hospital activity data were record linked and all diabetic and non-diabetic individuals over a four year period (1991-95) were identified. A cost weight was included for each admission based on diagnosis related groups.
Results—There were 10 214 patients admitted with a primary diagnostic code for CHD, representing an incidence of 6.3 per 1000 per annum. Including all CHD and non-CHD admissions, these individuals were responsible for 17% of acute inpatient activity. Men had a consistently higher age specific prevalence of CHD than women. The age adjusted relative risk of CHD for patients with diabetes compared with those without was 4.1 for men and 5.5 for women. Patients with diabetes accounted for 16.9% of CHD related admissions and had a fourfold increased probability of undergoing a cardiac procedure. The total cost of CHD was estimated to be 6% of NHS revenue at 1994-95 pay and prices. Patients with diabetes were responsible for 16% of this expenditure. This translated to an estimated NHS acute hospital expenditure for CHD of £1.1 billion per year at 1994-95 pay and prices.
Conclusions—CHD was responsible for a larger proportion of NHS expenditure than had previously been reported. Nearly one in five acute hospital admissions were for patients whose condition included cardiac problems. The relation between diabetes and CHD was particularly evident, and may offer opportunities for disease prevention.
Keywords: coronary heart disease; diabetes mellitus; cost and cost analysis; epidemiology 相似文献
Setting—The former South Glamorgan Health Authority, South Wales.
Methods—Routine hospital activity data were record linked and all diabetic and non-diabetic individuals over a four year period (1991-95) were identified. A cost weight was included for each admission based on diagnosis related groups.
Results—There were 10 214 patients admitted with a primary diagnostic code for CHD, representing an incidence of 6.3 per 1000 per annum. Including all CHD and non-CHD admissions, these individuals were responsible for 17% of acute inpatient activity. Men had a consistently higher age specific prevalence of CHD than women. The age adjusted relative risk of CHD for patients with diabetes compared with those without was 4.1 for men and 5.5 for women. Patients with diabetes accounted for 16.9% of CHD related admissions and had a fourfold increased probability of undergoing a cardiac procedure. The total cost of CHD was estimated to be 6% of NHS revenue at 1994-95 pay and prices. Patients with diabetes were responsible for 16% of this expenditure. This translated to an estimated NHS acute hospital expenditure for CHD of £1.1 billion per year at 1994-95 pay and prices.
Conclusions—CHD was responsible for a larger proportion of NHS expenditure than had previously been reported. Nearly one in five acute hospital admissions were for patients whose condition included cardiac problems. The relation between diabetes and CHD was particularly evident, and may offer opportunities for disease prevention.
Keywords: coronary heart disease; diabetes mellitus; cost and cost analysis; epidemiology 相似文献
103.
G S Reeder P J Currie D A Fyfe D J Hagler J B Seward A J Tajik 《Journal of the American College of Cardiology》1984,4(5):1006-1011
Extracardiac valved conduits are often employed in the repair of certain complex congenital heart defects; late obstruction is a well recognized problem that usually requires catheterization for definitive diagnosis. A reliable noninvasive method for detecting conduit stenosis would be clinically useful in identifying the small proportion of patients who develop this problem. Continuous wave Doppler echocardiography has been used successfully to estimate cardiac valvular obstructive lesions noninvasively. Twenty-three patients with prior extracardiac conduit placement for complex congenital heart disease underwent echocardiographic and continuous wave Doppler echocardiographic examinations to determine the presence and severity of conduit stenosis. In 20 of the 23 patients, an adequate conduit flow velocity profile was obtained, and in 10 an abnormally increased conduit flow velocity was present. All but one patient had significant obstruction proven at surgery and in one patient, surgery was planned. In three patients, an adequate conduit flow velocity profile could not be obtained but obstruction was still suspected based on high velocity tricuspid regurgitant Doppler signals. In these three patients, subsequent surgery also proved that conduit stenosis was present. Doppler-predicted gradients and right ventricular pressures showed an overall good correlation (r = 0.90) with measurements at subsequent cardiac catheterization. Continuous wave Doppler echocardiography appears to be a useful noninvasive tool for the detection and semiquantitation of extracardiac conduit stenosis. 相似文献
104.
T cell lymphoma occurring in Sj?gren's syndrome 总被引:2,自引:0,他引:2
105.
Lisa M. Currie Christy G. Woolcott Deshayne B. Fell B. Anthony Armson Linda Dodds 《Maternal and child health journal》2014,18(8):1823-1830
Some evidence, but not enough to be conclusive, suggests that physical activity in pregnancy reduces the risk of perinatal complications. Our objective was to examine if physical activity in the year before pregnancy and in the first half of pregnancy is associated with maternal and neonatal outcomes. Associations between physical activity and maternal and neonatal outcomes were examined in a prospective cohort (n = 1,749) in Halifax, Canada. The Kaiser Physical Activity Survey, completed at approximately 20 weeks’ gestation, requested information regarding physical activity during the year before the pregnancy and the first 20 weeks of pregnancy. Outcomes were assessed by medical chart review. Multiple logistic regression was used to estimate odds ratios (OR) with 95 % confidence intervals (CI). Women with prepregnancy physical activity levels in the middle and highest tertiles were more likely to have high gestational weight gain relative to women in the lowest tertile [OR (CI): 1.40 (1.06–1.85) and 1.57 (1.18–2.09), respectively]. Higher physical activity in the first half of pregnancy decreased the odds of delivering a macrosomic infant (p trend = 0.005). Associations were not observed between total physical activity and gestational diabetes, gestational hypertension, pre-eclampsia, preterm birth, and low birth weight. Physical activity before, but not in the first half of pregnancy, is associated with high gestational weight gain. Physical activity in the first half of pregnancy may reduce the occurrence of macrosomia without affecting preterm birth or low birth weight. 相似文献
106.
Aoife Mc Gillicuddy Maria Kelly Abina M. Crean Laura J. Sahm 《Research in social & administrative pharmacy》2019,15(12):1425-1435
BackgroundOral medicines are commonly modified (e.g. tablets split/crushed) to meet the dosing and swallowing requirements of older adults. However, there is limited research investigating the opinions of community-dwelling patients and carers about medicine modification.ObjectivesThe aim of this study was to investigate the views of community-dwelling older adults and their carers about oral medicine modification.MethodsSemi-structured, face-to-face interviews were conducted with community-dwelling older adults and carers of older adults who experienced difficulty swallowing medicines, or who required medicines to be modified. Participants were recruited from purposively selected community pharmacies using a combination of purposive, convenience and snowball sampling. Interviews were audio-recorded, transcribed verbatim and analysed thematically. The Francis method governed when data saturation had been reached.ResultsTwenty-six interviews (13 patients, 13 carers) were conducted (76.9% female, median length 11 min (IQR 8–16 min)). Four themes emerged from the data: variation in medical needs and preferences; balancing acceptance and resignation; healthcare professional engagement and; opportunities for optimising formulation suitability. The heterogeneity of medical conditions experienced by community-dwelling older adults resulted in a variety of modifications being required. Patients and carers are accepting of their medications and formulations. However, when challenges arise, they tend to feel resigned to coping within the constraints of the current medication regimen, resulting in a lack of focused communication with healthcare professionals. Thus, healthcare professionals were unaware of their difficulties and unable to offer advice or solutions.ConclusionHealthcare professionals must engage proactively with this group. Whilst a holistic approach to medication management is ideal, the disadvantage is that no single healthcare professional may identify this as their responsibility. Whilst the input and expertise of all healthcare professionals will be required, as medication experts, the pharmacy profession should take ownership and become the champion of, and for, the patient. 相似文献
107.
David B. Reuben MD Thomas M. Gill MD Alan Stevens PhD Jeff Williamson MD Elena Volpi MD PhD Maya Lichtenstein MD Lee A. Jennings MD MSHS Zaldy Tan MD Leslie Evertson DNP RN GNP-BC David Bass PhD Lisa Weitzman MSSA LISW-S ASW-G C-ASWCM Martie Carnie Nancy Wilson MA MSW Katy Araujo MPH Peter Charpentier MPH Can Meng MS MPH Erich J. Greene PhD James Dziura PhD Jodi Liu PhD MSPH MSE BSE Erin Unger Mia Yang MD Katherine Currie BSPH MAT Kristin M. Lenoir MPH Aval-NaʼRee S. Green MD Sitara Abraham MPH Ashley Vernon MPH Rafael Samper-Ternent MD PhD Mukaila Raji MD MSc Roxana M. Hirst MS Rebecca Galloway PT PhD Glen R. Finney MD Ilene Ladd MS Alanna Kulchak Rahm PhD MS CGC Pamela Borek MSN RN-C Peter Peduzzi PhD 《Journal of the American Geriatrics Society》2020,68(11):2492-2499
108.
Maral Ouzounian Maria E. Currie Karen J. Buth Alexandra M. Yip Ansar Hassan Gregory M. Hirsch 《The Canadian journal of cardiology》2014
Background
Women undergoing coronary artery bypass grafting (CABG) are at increased risk for morbidity and mortality. Factors responsible for this observation include smaller coronary size and delayed presentation. To date, no studies have examined the effect of the degree of myocardium at risk (MAR) on the relationship between female sex and adverse postoperative events.Methods
Consecutive patients undergoing first-time isolated CABG at a single institution from 2002-2007 were identified. MAR was calculated using the weighted Duke Index and was categorized as low, moderate, or high. Multivariable logistic regression models were created to compare the impact of MAR on adverse clinical events.Results
We identified 3741 patients, 3325 (89%) of whom had complete angiographic data. Women (n = 755) were older (P = 0.0001) and presented more often with hypertension (P = 0.0001), diabetes (P = 0.0001), heart failure (P = 0.0001), and an urgent/emergent situation (P = 0.002). After surgery, women experienced greater rates of adverse events (15.2% vs 9.3%; P = 0.0001). In a fully adjusted logistic regression model, the nested interaction of sex in MAR showed that women had a significantly greater risk of major adverse cardiovascular events (MACE) when MAR was high (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3-2.6; P = 0.0004). Greater severity of MAR emerged as an independent predictor of adverse events among women (high: OR, 2.9; 95% CI, 1.2-7.3; moderate: OR, 2.2; 95% CI, 0.8-5.7; low: OR, 1.0), but not among men.Conclusions
MAR was independently associated with higher rates of adverse events among women but not in men undergoing CABG. This finding may help explain differences in outcomes seen between women and men after revascularization. 相似文献109.
European Journal of Nuclear Medicine and Molecular Imaging - 相似文献
110.
Subramanian Nachiappan Alan Askari Andrew Currie Robin H. Kennedy Omar Faiz 《Surgical endoscopy》2014,28(9):2513-2530