Quantitative approaches to the study of bistability in the
            lac
            operon of
            Escherichia coli

In this paper, the history and importance of the lac operon in the development of molecular and systems biology are briefly reviewed. We start by presenting a description of the regulatory mechanisms in this operon, taking into account the most recent discoveries. Then we offer a survey of the history of the lac operon, including the discovery of its main elements and the subsequent influence on the development of molecular and systems biology. Next the bistable behaviour of the operon is discussed, both with respect to its discovery and its molecular origin. A review of the literature in which this bistable phenomenon has been studied from a mathematical modelling viewpoint is then given. We conclude with some brief remarks.

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Reverse engineering and identification in systems biology: strategies, perspectives and challenges

Journal of The Royal Society Interface ◽

10.1098/rsif.2013.0505 ◽

2014 ◽

Vol 11 (91) ◽

pp. 20130505 ◽

Cited By ~ 131

Author(s):

Alejandro F. Villaverde ◽

Julio R. Banga

Keyword(s):

Machine Learning ◽

Inverse Problem ◽

Systems Biology ◽

Mathematical Modelling ◽

Reverse Engineering ◽

Chemical Kinetics ◽

Regulatory Mechanisms ◽

Engineering Problems ◽

Central Elements ◽

Key Questions

The interplay of mathematical modelling with experiments is one of the central elements in systems biology. The aim of reverse engineering is to infer, analyse and understand, through this interplay, the functional and regulatory mechanisms of biological systems. Reverse engineering is not exclusive of systems biology and has been studied in different areas, such as inverse problem theory, machine learning, nonlinear physics, (bio)chemical kinetics, control theory and optimization, among others. However, it seems that many of these areas have been relatively closed to outsiders. In this contribution, we aim to compare and highlight the different perspectives and contributions from these fields, with emphasis on two key questions: (i) why are reverse engineering problems so hard to solve, and (ii) what methods are available for the particular problems arising from systems biology?

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Escherichia coli endocarditis. A review of the literature and a case study

Archives of Internal Medicine ◽

10.1001/archinte.120.4.472 ◽

1967 ◽

Vol 120 (4) ◽

pp. 472-477 ◽

Cited By ~ 4

Author(s):

C. E. Hansing

Keyword(s):

Escherichia Coli ◽

Review Of The Literature

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Pneumomediastinum: A Rare Presentation of Inflicted Injuries in Infants

Journal of Pediatric Intensive Care ◽

10.1055/s-0040-1716857 ◽

2020 ◽

Author(s):

Adam Lee ◽

Adam Bajinting ◽

Abby Lunneen ◽

Colleen M. Fitzpatrick ◽

Gustavo A. Villalona

Keyword(s):

Literature Review ◽

Retrospective Review ◽

Review Of The Literature ◽

Rare Presentation ◽

Spontaneous Pneumomediastinum ◽

Nonaccidental Trauma ◽

Comprehensive Literature Review ◽

Healthy Infants ◽

History Of

AbstractReports of incidental pneumomediastinum in infants secondary to inflicted trauma are limited. A retrospective review of infants with pneumomediastinum and history of inflicted trauma was performed. A comprehensive literature review was performed. Three infants presented with pneumomediastinum associated with inflicted trauma. Mean age was 4.6 weeks. All patients underwent diagnostic studies, as well as a standardized evaluation for nonaccidental trauma. All patients with pneumomediastinum were resolved at follow-up. Review of the literature identified other cases with similar presentations with related oropharyngeal injuries. Spontaneous pneumomediastinum in previously healthy infants may be associated with inflicted injuries. Clinicians should be aware of the possibility of an oropharyngeal perforation related to this presentation.

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History of Extensive Disease Small Cell Lung Cancer Treatment: Time to Raise the Bar? A Review of the Literature

Cancers ◽

10.3390/cancers13050998 ◽

2021 ◽

Vol 13 (5) ◽

pp. 998

Author(s):

Chiara Lazzari ◽

Aurora Mirabile ◽

Alessandra Bulotta ◽

Maria Grazia Viganó ◽

Francesca Rita Ogliari ◽

...

Keyword(s):

Lung Cancer ◽

Small Cell Lung Cancer ◽

Cell Lung Cancer ◽

Treatment Time ◽

Small Cell ◽

Review Of The Literature ◽

Small Cell Lung ◽

Extensive Disease ◽

History Of ◽

Line Standard

Several trials have tried for decades to improve the outcome of extensive disease small cell lung cancer (ED-SCLC) through attempts to modify the standard treatments. Nevertheless, platinum/etoposide combination and topotecan have remained respectively the first and the second line standard treatments for the last 40 years. With the advent of immunotherapy, this scenario has finally changed. Our review aims to provide an overview of the primary studies on the actual therapeutic strategies available for ED-SCLC patients, and to highlight emerging evidence supporting the use of immunotherapy in SCLC patients.

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Lac Operon Boolean Models: Dynamical Robustness and Alternative Improvements

Mathematics ◽

10.3390/math9060600 ◽

2021 ◽

Vol 9 (6) ◽

pp. 600 ◽

Cited By ~ 1

Author(s):

Marco Montalva-Medel ◽

Thomas Ledger ◽

Gonzalo A. Ruz ◽

Eric Goles

Keyword(s):

Escherichia Coli ◽

Limit Cycles ◽

The Other ◽

Lac Operon ◽

Boolean Models ◽

Bistable Behavior

In Veliz-Cuba and Stigler 2011, Boolean models were proposed for the lac operon in Escherichia coli capable of reproducing the operon being OFF, ON and bistable for three (low, medium and high) and two (low and high) parameters, representing the concentration ranges of lactose and glucose, respectively. Of these 6 possible combinations of parameters, 5 produce results that match with the biological experiments of Ozbudak et al., 2004. In the remaining one, the models predict the operon being OFF while biological experiments show a bistable behavior. In this paper, we first explore the robustness of two such models in the sense of how much its attractors change against any deterministic update schedule. We prove mathematically that, in cases where there is no bistability, all the dynamics in both models lack limit cycles while, when bistability appears, one model presents 30% of its dynamics with limit cycles while the other only 23%. Secondly, we propose two alternative improvements consisting of biologically supported modifications; one in which both models match with Ozbudak et al., 2004 in all 6 combinations of parameters and, the other one, where we increase the number of parameters to 9, matching in all these cases with the biological experiments of Ozbudak et al., 2004.

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