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51.
Carlos A. López-Quintero Lea Atanasova A. Esperanza Franco-Molano Walter Gams Monika Komon-Zelazowska Bart Theelen Wally H. Müller Teun Boekhout Irina Druzhinina 《Antonie van Leeuwenhoek》2013,104(5):657-674
The diversity of Trichoderma (Hypocreales, Ascomycota) colonizing leaf litter as well as the rhizosphere of Garcinia macrophylla (Clusiaceae) was investigated in primary and secondary rain forests in Colombian Amazonia. DNA barcoding of 107 strains based on the internal transcribed spacers 1 and 2 (ITS1 and 2) of the ribosomal RNA gene cluster and the partial sequence of the translation elongation factor 1 alpha (tef1) gene revealed that the diversity of Trichoderma was dominated (71 %) by three common cosmopolitan species, namely Trichoderma harzianum sensu lato (41 %), Trichoderma spirale (17 %) and Trichoderma koningiopsis (13 %). Four ITS 1 and 2 phylotypes (13 strains) could not be identified with certainty. Multigene phylogenetic analysis and phenotype profiling of four strains with an ITS1 and 2 phylotype similar to Trichoderma strigosum revealed a new sister species of the latter that is described here as Trichoderma strigosellum sp. nov. Sequence similarity searches revealed that this species also occurs in soils of Malaysia and Cameroon, suggesting a pantropical distribution. 相似文献
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Pollen grains of eieven species of Pariana, a small genus of herbaceous bamboos, were studied using LM, SEM and TEM. Ten of them have the Pariana stenolemma-type of pollen characterized by areolate exine due to relatively high and well separated denticulate processes on a slightly undulated tectum, vestigial columellae and no distinct annulus. At the pore edge the foot layer is thickened and folded. P. campetris (P. campestris-type) shows this exine feature only at magnifications higher than x 2000, whereas the denticulate processes are clearly visible at x 400 magnification in the other ten species. The pores are bordered by a distinct annulus. The high relief of the Pariana pollen forming a relatively rough surface would offer more friction in wind transport than the smooth surface of other grass pollen grains. Insects visiting the flowers have been observed which support the idea of possible insect pollination. If this would be the case, the parianas would be an example of correlation between pollen form and function in the evolution of the Gramineae. 相似文献
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Natalia J. Martinez Ganesha Rai Adam Yasgar Wendy A. Lea Hongmao Sun Yuhong Wang Diane K. Luci Shyh-Ming Yang Kana Nishihara Shunichi Takeda Mohiuddin Irina Earnshaw Tetsuya Okada Kazutoshi Mori Kelli Wilson Gregory J. Riggins Menghang Xia Maurizio Grimaldi Ajit Jadhav David J. Maloney Anton Simeonov 《PloS one》2016,11(11)
56.
Lea A. Rempel Megan M. Krautkramer John J. Parrish Jeremy R. Miles 《Molecular reproduction and development》2019,86(4):465-475
Epigenetics includes the study of external factors that can influence the expression of genes by altering the accessibility of DNA through methylation. To investigate the epigenetic influence of season, sperm head shape, and semen storage on placental and fetal tissues, pregnancies were generated in the summer or winter using boar semen from either least or most sperm head shape change, collected during cool or warm seasons, and stored as cooled‐extended or cryopreserved. The lowest (p < 0.05) ratios of 5‐methylcytosine to 5‐hydroxymethylcytosine activity (5mC:5hmC) in fetal liver were from summer breedings and in placental tissues from winter breedings. The relative expression of placental CDH1 tended ( p < 0.10) to be greater in placenta generated from cryopreserved semen or semen collected during cool periods. The relative expression of placental GNAS was affected ( p < 0.05) by the interaction of breeding and semen collection seasons. Cryopreserved semen increased ( p < 0.05) the placental relative expression of GNAS. Placental MEST and RHOBTB3 tended ( p < 0.10) to have a greater relative expression from pregnancies generated using semen collected during cool periods used during winter breedings. Within fetal liver, the relative expression of GNAS and HGF was greater ( p < 0.05) from winter breedings. Interaction of winter breedings and least sperm head shape change tended ( p < 0.10) to have the greatest fetal liver expression of CDH1. Seasonality of semen collection, breeding, and the effect on sperm head shape change had an influence on the expression of genes with known differentially methylated regions or response to methylation activity from embryonic and extraembryonic tissues. 相似文献
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Adamo KB Dent R Langefeld CD Cox M Williams K Carrick KM Stuart JS Sundseth SS Harper ME McPherson R Tesson F 《Obesity (Silver Spring, Md.)》2007,15(5):1068-1075
Peroxisome proliferator-activated receptor gamma (PPARgamma) and its response gene, Acyl CoA synthetase 5 (ACSL5), which has an important role in fatty acid metabolism, may affect weight loss in response to caloric restriction. Therefore, we aimed to determine whether these genes were involved in the interindividual response to dietary treatment. Genotypic/phenotypic comparisons were made between selected obese women from the quintiles losing the most (diet responsive, n = 74) and the quintiles losing the least (diet-resistant, n = 67) weight in the first 6 weeks of a 900-kcal formula diet. Two common PPARgamma single nucleotide polymorphisms, Pro(12)Ala and C1431T, and eight polymorphisms across the ACSL5 gene were selected for single locus and haplotypic association analyses. The PPARgamma Pro(12)Ala single nucleotide polymorphism was associated with diet resistance (odds ratio = 3.48, 95% confidence interval = 1.41 to 8.56, p = 0.03), and the rs2419621, located in the 5'untranslated region of the ACSL5 gene, displayed the strongest association with diet response (odds ratio = 3.45, 95% confidence interval = 1.61 to 7.69, p = 0.001). Skeletal muscle ACSL5 mRNA expression was significantly lower in carriers of the wildtype compared with the variant rs2419621 allele (p = 0.03). Our results suggest a link between PPARgamma2 and ACSL5 genotype and diet responsiveness. 相似文献
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First Nations status and emergency department triage scores in Alberta: a retrospective cohort study
Patrick McLane Cheryl Barnabe Leslee Mackey Lea Bill Katherine Rittenbach Brian R. Holroyd Anne Bird Bonnie Healy Kris Janvier Eunice Louis Rhonda J. Rosychuk 《CMAJ》2022,194(2):E37
Background:Previous studies have found that race is associated with emergency department triage scores, raising concerns about potential health care inequity. As part of a project on quality of care for First Nations people in Alberta, we sought to understand the relation between First Nations status and triage scores.Methods:We conducted a population-based retrospective cohort study of health administrative data from April 2012 to March 2017 to evaluate acuity of triage scores, categorized as a binary outcome of higher or lower acuity score. We developed multivariable multilevel logistic mixed-effects regression models using the levels of emergency department visit, patient (for patients with multiple visits) and facility. We further evaluated the triage of visits related to 5 disease categories and 5 specific diagnoses to better compare triage outcomes of First Nations and non–First Nations patients.Results:First Nations status was associated with lower odds of receiving higher acuity triage scores (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.92–0.94) compared with non–First Nations patients in adjusted models. First Nations patients had lower odds of acute triage for all 5 disease categories and for 3 of 5 diagnoses, including long bone fractures (OR 0.82, 95% CI 0.76–0.88), acute upper respiratory infection (OR 0.90, 95% CI 0.84–0.98) and anxiety disorder (OR 0.67, 95% CI 0.60–0.74).Interpretation:First Nations status was associated with lower odds of higher acuity triage scores across a number of conditions and diagnoses. This may reflect systemic racism, stereotyping and potentially other factors that affected triage assessments.Health outcomes are markedly worse for First Nations than non–First Nations people. Although this is largely because of inequities in the social determinants of health,1–4 inequities in the provision of health care also exist.5,6 Emergency departments serve as a point of accessible health care. Status First Nations patients make up 4.8% of unique patients and 9.4% of emergency visits in Alberta,7 and Canadian studies describe First Nations patients’ experiences with racism when seeking emergency care.8,9Evaluating triage contributes empirically to understanding the health care of First Nations patients insofar as triage is a quantifiable, intermediate process by which systemic racism10 may influence patient outcomes. The Canadian Triage Acuity Scale11 is a 5-level scale used to classify the severity of patient symptoms. Triage nurses use a brief assessment, medical history, and presenting signs and symptoms to assign each patient a triage score that determines the priority in which the patient should be seen by a provider. Therefore, accurate triage is important for patient health outcomes.12 In practice, triage is a social interaction where local practice, biases, stereotypes and communication barriers come into play. Studies have found that women receive less acute triage scores than men,13,14 and that racial minority13,15–17 and Indigenous18–20 patients receive less acute triage scores than white or non-Indigenous patients. Indeed, Indigenous patients in Canada have described a perception “of social triaging in the [emergency department], whereby decisions about who is seen first seemed to them [to be] based less on triaged clinical priorities but on the social positioning of the patient.”21 Differential triage scores for minority populations raise health equity concerns.As part of a larger mixed-methods project evaluating the quality of emergency care for First Nations people in Alberta, we sought to evaluate quantitative differences in emergency visit characteristics and outcomes of First Nations and non–First Nations people in Alberta. Specifically, we aimed to estimate the relation between First Nations status and acuity of triage, and to evaluate whether predictors of acuity differ by First Nations status. 相似文献