scholarly journals The roles of history, chance, and natural selection in the evolution of antibiotic resistance

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alfonso Santos-Lopez ◽  
Christopher W Marshall ◽  
Allison L Haas ◽  
Caroline B Turner ◽  
Javier Rasero ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
New Drugs ◽  
Prior History ◽  
Collateral Sensitivity ◽  
Selective Pressures ◽  
Loss Of Resistance ◽  
History Of ◽  
Compensatory Mutations ◽  
Initial Drug ◽  
Selection Of

History, chance, and selection are the fundamental factors that drive and constrain evolution. We designed evolution experiments to disentangle and quantify effects of these forces on the evolution of antibiotic resistance. Previously we showed that selection of the pathogen Acinetobacter baumannii in both structured and unstructured environments containing the antibiotic ciprofloxacin produced distinct genotypes and phenotypes, with lower resistance in biofilms as well as collateral sensitivity to b-lactam drugs (Santos-Lopez et al. 2019). Here we study how this prior history influences subsequent evolution in new b-lactam antibiotics. Selection was imposed by increasing concentrations of ceftazidime and imipenem and chance differences arose as random mutations among replicate populations. The effects of history were reduced by increasingly strong selection in new drugs, but not erased, at times revealing important contingencies. A history of selection in structured environments constrained resistance to new drugs and led to frequent loss of resistance to the initial drug by genetic reversions and not compensatory mutations. This research demonstrates that despite strong selective pressures of antibiotics leading to genetic parallelism, history can etch potential vulnerabilities to orthogonal drugs.

scholarly journals The roles of history, chance, and natural selection in the evolution of antibiotic resistance

2020 ◽  
Author(s):  
Alfonso Santos-Lopez ◽  
Christopher W. Marshall ◽  
Allison L. Welp ◽  
Caroline Turner ◽  
Javier Rasero ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Natural Selection ◽  
New Drugs ◽  
Antibiotic Selection ◽  
Selective Pressures ◽  
Unstructured Environments ◽  
Loss Of Resistance ◽  
New Antibiotics ◽  
Initial Drug ◽  
Selection Of

AbstractHistory, chance, and selection are the fundamental factors that drive and constrain evolution. We designed evolution experiments to disentangle and quantify effects of these forces on the evolution of antibiotic resistance. History was established by prior antibiotic selection of the pathogen Acinetobacter baumannii in both structured and unstructured environments, selection occurred in increasing concentrations of new antibiotics, and chance differences arose as random mutations among replicate populations. The effects of history were reduced by increasingly strong selection in new drugs, but not erased, at times producing important contingencies. Selection in structured environments constrained resistance to new drugs and led to frequent loss of resistance to the initial drug. This research demonstrates that despite strong selective pressures of antibiotics leading to genetic parallelism, history can etch potential vulnerabilities to orthogonal drugs.

scholarly journals The chemotherapeutic drug methotrexate selects for antibiotic resistance

2020 ◽  
Author(s):  
Jónína S. Gudmundsdóttir ◽  
Elizabeth G. A. Fredheim ◽  
Catharina I. M. Koumans ◽  
Joachim Hegstad ◽  
Po-Cheng Tang ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Antibacterial Properties ◽  
Treatment Strategies ◽  
Bacterial Populations ◽  
E Coli ◽  
Resistance Evolution ◽  
Selective Pressures ◽  
Methotrexate Chemotherapy ◽  
Selection Of

AbstractUnderstanding drivers of antibiotic resistance evolution is fundamental for designing optimal treatment strategies and interventions to reduce the spread of antibiotic resistance. Various cytotoxic drugs used in cancer chemotherapy have antibacterial properties, but how bacterial populations are affected by these selective pressures is unknown. Here we test the hypothesis that the widely used cytotoxic drug methotrexate affects the evolution and selection of antibiotic resistance through the same mechanisms as the antibiotic trimethoprim. We show that methotrexate can select for trimethoprim resistance determinants located on the chromosome or a plasmid in clinical strains of Escherichia coli. Additionally, methotrexate can co-select for virtually any antibiotic resistance determinant when present together with trimethoprim resistance on a multidrug-resistance clinical plasmid. These selective effects occur at concentrations 40- to >320-fold below the methotrexate minimal inhibitory concentration for E. coli, suggesting a selective role of methotrexate chemotherapy for antibiotic resistance in patients that strongly depend on effective antibiotic treatment.

Conclusion: What is Speculative Empiricism?

2018 ◽  
Author(s):  
Didier Debaise
Keyword(s):  
Social Groups ◽  
Speculative Philosophy ◽  
System P ◽  
History Of ◽  
Selection Of

Process and Reality ends with a warning: ‘[t]he chief danger to philosophy is narrowness in the selection of evidence’ (PR, 337). Although this danger of narrowness might emerge from the ‘idiosyncrasies and timidities of particular authors, of particular social groups, of particular schools of thought, of particular epochs in the history of civilization’ (PR, 337), we should not be mistaken: it occurs within philosophy, in its activity, its method. And the fact that this issue arises at the end of Process and Reality reveals the ambition that has accompanied its composition: Whitehead has resisted this danger through the form and ambition of his speculative construction. The temptation of a narrowness in selection attempts to expel speculative philosophy at the same time as it haunts each part of its system.

Displace of Documentary Heritage from the Soviet Union to Poland during the Third Decade of the XXth Century

2014 ◽  
Vol 3 ◽  
pp. 127-137
Author(s):  
Tatsiana Hiarnovich
Keyword(s):  
Soviet Union ◽  
International Agreements ◽  
Peace Treaty ◽  
Actual Process ◽  
Xxth Century ◽  
The Third ◽  
The Soviet Union ◽  
History Of ◽  
Selection Of

The paper explores the displace of Polish archives from the Soviet Union that was performed in 1920s according to the Riga Peace Treaty of 1921 and other international agreements. The aim of the research is to reconstruct the process of displace, based on the archival sources and literature. The object of the research is those documents that were preserved in the archives of Belarus and together with archives from other republics were displaced to Poland. The exploration leads to clarification of the selection of document fonds to be displaced, the actual process of movement and the explanation of the role that the archivists of Belarus performed in the history of cultural relationships between Poland and the Soviet Union. The articles of the Treaty of Riga had been formulated without taking into account the indivisibility of archive fonds that is one of the most important principles of restitution, which caused the failure of the treaty by the Soviet part.

Diagnostic approach to causes of spinal pain

2018 ◽  
pp. 66-70
Author(s):  
F. D. Nasirova
Keyword(s):  
Spinal Pain ◽  
Rapid Loss ◽  
Loss Of Weight ◽  
History Of ◽  
Radiologic Investigation ◽  
Males And Females ◽  
Serious Disease ◽  
Pain At Rest ◽  
Oncologic Diseases ◽  
Selection Of

Causes of spinal pain are extremely varying. Sex composition of patients referring with spinal pain at the age of 16 to 35 was 35% and 65% for males and females, respectively. Peak number of complaints was observed in 30-40 years age group of highest work ability. The followings should be considered as precautions in spinal pain: onset of pain at the age of 20 and after 50, family history of oncologic diseases, walking disorders or dysfunctions of sphincters, numbness in extremities, general malaise and rapid loss of weight, pain at rest and primarily at night, as these conditions may be a warning of underlying serious disease. Selection of algorithm for radiologic investigation is decided by the treating physician.

Philosophcal review of h. white̕s tropological theory in the context of the new philosophy of history

2020 ◽  
Vol 3 (152) ◽  
pp. 92-99
Author(s):  
S. M. Geiko ◽  
◽  
O. D. Lauta
Keyword(s):  
Modern Science ◽  
Historical Knowledge ◽  
Text Organization ◽  
The Social ◽  
History Of ◽  
Actual Material ◽  
The Common ◽  
Historical Nature ◽  
Selection Of

The article provides a philosophical analysis of the tropological theory of the history of H. White. The researcher claims that history is a specific kind of literature, and the historical works is the connection of a certain set of research and narrative operations. The first type of operation answers the question of why the event happened this way and not the other. The second operation is the social description, the narrative of events, the intellectual act of organizing the actual material. According to H. White, this is where the set of ideas and preferences of the researcher begin to work, mainly of a literary and historical nature. Explanations are the main mechanism that becomes the common thread of the narrative. The are implemented through using plot (romantic, satire, comic and tragic) and trope systems – the main stylistic forms of text organization (metaphor, metonymy, synecdoche, irony). The latter decisively influenced for result of the work historians. Historiographical style follows the tropological model, the selection of which is determined by the historian’s individual language practice. When the choice is made, the imagination is ready to create a narrative. Therefore, the historical understanding, according to H. White, can only be tropological. H. White proposes a new methodology for historical research. During the discourse, adequate speech is created to analyze historical phenomena, which the philosopher defines as prefigurative tropological movement. This is how history is revealed through the art of anthropology. Thus, H. White’s tropical history theory offers modern science f meaningful and metatheoretically significant. The structure of concepts on which the classification of historiographical styles can be based and the predictive function of philosophy regarding historical knowledge can be refined.

Dynamics of Immigration: From Humanitarianism to Securitization

2018 ◽  
Author(s):  
Reumah Suhail
Keyword(s):  
World War Ii ◽  
Host Country ◽  
Country Of Origin ◽  
Immigration Policies ◽  
World War ◽  
Post World War Ii ◽  
Immigration Process ◽  
History Of ◽  
Selection Of

The paper addresses the different aspects of the politics of immigration, the underlying factors that motivate, force or pressurize people to move from their country of origin to new abodes in foreign nations. In the introduction the paper discusses different theories playing their due role in the immigration process, namely Realism and Constructivism. The paper examines the history of immigration and post-World War II resettlement followed by an analysis of how immigration policies are now centered towards securitization as opposed to humanitarianism after 9/11, within the scenario of globalization. Muslim migrant issues and more stringent immigration policies are also weighed in on, followed by a look at immigration in regions which are not hotspot settlement destinations. Lastly an analysis is presented about the selection of a host country a person opts for when contemplating relocation; a new concept is also discussed and determined whereby an individual can opt for “citizenship by investment” and if such a plan is an accepted means of taking on a new nationality.

Herbal Medicine: Clinical Perspective & Regulatory Status

2020 ◽  
Vol 23 ◽  
Author(s):  
Md Abul Barkat ◽  
Anjali Goyal ◽  
Harshita Abul Barkat ◽  
Mohammad Salauddin ◽  
Faheem Hyder Pottoo ◽  
...  
Keyword(s):  
Herbal Medicine ◽  
Herbal Medicines ◽  
New Drugs ◽  
Herbal Drugs ◽  
Clinical Perspective ◽  
Regulatory Status ◽  
Novel Drugs ◽  
History Of ◽  
Pros And Cons ◽  
Health Complications

Abstract:: Herbal medicines pays an important in treating the vaious diseases mainly due to the their potentially high therapeutic values and also due to the better acceptance of vaioruspatient under different health complications. The herbal medicine practice involves use of part of plant, entire plant or the selectctive isolated phytomedicineand the use and practices based on these has its pros and cons and has been greatly affected during the dawn. The search of new drugs during scientific era revives the interest in discovery of herbal drugs from different natural resources during 20th century. The present modern healthcare system invovlves utilization drugs and 50% of them are of ofnaural origin. Herbal drug disocovery found to be highly costly affair with low success rate and it hinders the further progress in utilizting the phytomedicine in treating the various deseases. But in recent years there is an increase in the search interest of herbal drugs mainly by the pharmaceutical industry and those invoves in the search of novel drugs from the herbs. Discovery of such new novel phytomedicines has to overcomes various challenges in indentification of active extracts and their toxicity, advereffects, herb drug interaction and importantly their regulatory requirments. The present review mainly focused on the history of herbal medicine, current clinical perspective, pharmaceutical, and regulatory challenges as well as its clinical presentation. Moreover, problems encountered in drug discovery from herbal resources and its possible solutions are delineated.

High Risk of One-year Stroke Recurrence in Patients with Younger Age and Prior History of Ischemic Stroke

2019 ◽  
Vol 16 (3) ◽  
pp. 250-257 ◽  
Author(s):  
Jiann-Der Lee ◽  
Ya-Han Hu ◽  
Meng Lee ◽  
Yen-Chu Huang ◽  
Ya-Wen Kuo ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Ischemic Stroke ◽  
Multivariate Logistic Regression Analysis ◽  
Stroke Recurrence ◽  
Prior History ◽  
Multivariate Logistic Regression ◽  
Cart Analysis ◽  
Younger Age ◽  
History Of ◽  
One Year

Background and Purpose: Recurrent ischemic strokes increase the risk of disability and mortality. The role of conventional risk factors in recurrent strokes may change due to increased awareness of prevention strategies. The aim of this study was to explore the potential risk factors besides conventional ones which may help to affect the advances in future preventive concepts associated with one-year stroke recurrence (OSR). Methods: We analyzed 6,632 adult patients with ischemic stroke. Differences in clinical characteristics between patients with and without OSR were analyzed using multivariate logistic regression and classification and regression tree (CART) analyses. Results: Among the study population, 525 patients (7.9%) had OSR. Multivariate logistic regression analysis revealed that male sex (OR 1.243, 95% CI 1.025 – 1.506), age (OR 1.015, 95% CI 1.007 - 1.023), and a prior history of ischemic stroke (OR 1.331, 95% CI 1.096 – 1.615) were major factors associated with OSR. CART analysis further identified age and a prior history of ischemic stroke were important factors for OSR when classified the patients into three subgroups (with risks of OSR of 8.8%, 3.8%, and 12.5% for patients aged > 57.5 years, ≤ 57.5 years/with no prior history of ischemic stroke, and ≤ 57.5 years/with a prior history of ischemic stroke, respectively). Conclusions: Male sex, age, and a prior history of ischemic stroke could increase the risk of OSR by multivariate logistic regression analysis, and CART analysis further demonstrated that patients with a younger age (≤ 57.5 years) and a prior history of ischemic stroke had the highest risk of OSR.

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