314 research outputs found
Terpene synthase genes originated from bacteria through horizontal gene transfer contribute to terpenoid diversity in fungi
Fungi are successful eukaryotes of wide distribution. They are known as rich producers of secondary metabolites, especially terpenoids, which are important for fungi-environment interactions. Horizontal gene transfer (HGT) is an important mechanism contributing to genetic innovation of fungi. However, it remains unclear whether HGT has played a role in creating the enormous chemical diversity of fungal terpenoids. Here we report that fungi have acquired terpene synthase genes (TPSs), which encode pivotal enzymes for terpenoid biosynthesis, from bacteria through HGT. Phylogenetic analysis placed the majority of fungal and bacterial TPS genes from diverse taxa into two clades, indicating ancient divergence. Nested in the bacterial TPS clade is a number of fungal TPS genes that are inferred as the outcome of HGT. These include a monophyletic clade of nine fungal TPS genes, designated as BTPSL for bacterial TPS-like genes, from eight species of related entomopathogenic fungi, including seven TPSs from six species in the genus Metarhizium. In vitro enzyme assays demonstrate that all seven BTPSL genes from the genus Metarhizium encode active enzymes with sesquiterpene synthase activities of two general product profiles. By analyzing the catalytic activity of two resurrected ancestral BTPSLs and one closely related bacterial TPS, the trajectory of functional evolution of BTPSLs after HGT from bacteria to fungi and functional divergence within Metarhizium could be traced. Using M. brunneum as a model species, both BTPSLs and typical fungal TPSs were demonstrated to be involved in the in vivo production of terpenoids, illustrating the general importance of HGT of TPS genes from bacteria as a mechanism contributing to terpenoid diversity in fungi
Angiotensin-converting enzyme inhibitors but not angiotensin II AT 1 receptor antagonists affect erythropoiesis in patients with anemia of end-stage renal disease
Donor gender does not affect liver transplantation outcome in children
The liver is recognized as a sex hormone-responsive organ. Gender-specific differences in liver function are known to exist. Recently, a higher failure rate for organs transplanted in adults from female donors to male recipients has been reported. This increased failure rate of livers obtained from adult females and transplanted into adult males is thought to occur, at least in part, as a result of intrinsic gender-specific differences in hepatocyte cell surface expression and to alterations in the hormonal milieu of the donor liver in the recipient. To determine whether the same graft-recipient gender-determined failure rates pertain in the pediatric liver transplant population, the outcome of 335 primary liver transplants performed in children at the University of Pittsburgh Medical Center was examined. No difference in transplant outcome was demonstrated in children based on the gender pairings between the donor and recipient whether or not variables such as the age, etiology of the liver disease, and the blood group of the recipient were included in the data analysis. Thus, in contrast, to the situation in adults, the gender of the donor does not influence the outcome of liver transplantation in children and should not be used as a criterion for donor selection. This difference between adults and children may be due, at least in part, to gender differences in hepatocyte phenotypic expression induced as a consequence of puberty. © 1990 Plenum Publishing Corporation
Increased expression of Tbet in CD4+ T cells from clinically isolated syndrome patients at high risk of conversion to clinically definite MS
Journalism, science, and integrity
Trust is the basis of the relationship between journalists and scientists, between editors and scientists, as we recall here, in an article based on our experience of several decades of publishing in the press and publishing industry. The integrity of specialists, whose initial writings are reviewed by their peers, is not a priori questioned. However, shortcomings do exist and the question of verifying information, its sources and even its veracity is increasingly being raised. It is also necessary to ensure that the writings do not contain plagiarism (or self-plagiarism) or fraud. Publications (newspapers, magazines, books, etc.) could then be accused of counterfeiting or copyright infringement - which could cost them dearly - and lose their credibility. In addition to academic standards, legal standards apply here. Some concrete examples that we have had to deal with, both in the press and in publishing, illustrate our point
Learning disease progression models with longitudinal data and missing values
International audienceStatistical methods have been developed for the analysis of longitudinal data in neurodegenerative diseases. To cope with the lack of temporal markers-i.e. to account for subject-specific disease progression in regard to age-a common strategy consists in realigning the individual sequence data in time. Patient's specific trajectories can indeed be seen as spatiotemporal perturbations of the same normative disease trajectory. However, these models do not easily allow one to account for multimodal data, which more than often include missing values. Indeed, it is rare that imaging and clinical examinations for instance are performed at the same frequency in clinical protocols. Multimodal models also need to allow a different profile of progression for data with different structure and representation. We propose to use a generative mixed effect model that considers the progression trajectories as curves on a Rieman-nian Manifold. We use the concept of product manifold to handle multimodal data, and leverage the generative aspect of our model to handle missing values. We assess the robuste-ness of our methods toward missing values frequency on both synthetic and real data. Finally we apply our model on a real-world dataset to model Parkinson's disease progression from data derived from clinical examination and imaging
Foreword
The forest, a natural resource and mirror on our time It is generally considered that the European temperate forest gradually became established during the Holocene epoch, some 10,000 years BP. Its history, in the true sense of the word, began with the first real impacts of sedentary and agricultural man in the Neolithic era, around 7,000 years BP for the area that is now southern France. Thus the long story of man and the forest began, a story that has been marked by the contractions and exp..
Rivers we can't bring ourselves to clean – historical insights into the pollution of the Moselle River (France), 1850–2000
International audienceAs products of both natural and social systems, rivers are highly complex historical objects. We show in this paper that historical analysis works on two different levels: one level, which we call "structural", shows the materiality of the riverine environment as the spatial-temporal product of natural factors and human impacts (bed and course alterations, pollution, etc.). On a second level – "semiotic" – we show that river systems are also social constructs and the subjects of ancient and diverse management practices. The quality of a river will be a function of the dialectical interaction between both levels. Historical analysis can uncover the inherited constraints that bear upon current management practices. To help substantiate this analytical framework, we analyse the case of the Moselle river in eastern France by using archival sources and statistical data. Severely impaired by industrial discharges from iron, coal and salt industries between the 1875s and the early 1980s, the waters of the Moselle became the subject of a social consensus between stakeholders that prevented the implementation of efficient pollution management policies until the 1990s. The example urges caution on the pervasiveness of participatory approaches to river management: social consensus does not necessarily benefit the environment
The role of aging, body mass index and estrogen on symptomatic lumbar osteoarthritis in post-menopausal women
Background: Low back pain is a common complaint which is always found in old age due to degeneration process. Degeneration process of spine, especially in the lumbar region is called lumbar osteoarthritis (OA). Various factors are thought to be the cause of lumbar OA, including primarily due to hormonal changes of estrogen and increase of age and body mass index in postmenopausal women.Methods: The purpose of this study is to determine the role of hormonal changes pathogenesis in lumbar osteoarthritis in postmenopausal women and its correlation with age and body mass index. Cross sectional analytic method had been conducted to determine the role of age, body mass index and estrogen for lumbar OA in postmenopausal women. The study was conducted in Sanglah General Hospital from October 2015 until March 2016 by anthropometric measures and blood samples.Results: From 196 samples showed that the estrogen deficiency in postmenopausal women have a correlation with the symptomatic lumbar OA (r=0.252, p = 0.000). While age and the body mass index in postmenopausal women has a correlation with symptomatic lumbar OA (r = 0.150 and 0.198, p = 0.000 and 0.013).Conclusions: The aging process, body mass index and estrogen deficiency correlated with the symptomatic OA lumbar in post-menopausal women
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