Read by QxMD icon Read

Mathematical model tuberculosis

Gaurav D Sankhe, Narendra M Dixit, Deepak K Saini
Two-component signaling systems (TCSs) are central to bacterial adaptation. However, the mechanisms underlying the reactions involving TCS proteins and their reaction rates are largely undetermined. Here, we employed a combined experimental and theoretical approach to elucidate the kinetics of autophosphorylation of three histidine kinases (HKs) of Mycobacterium tuberculosis , viz. , MtrB, PrrB, and PhoR, all known to play a role in regulating its virulence. Using wild-type and mutant proteins, we performed dimerization assays, thermophoretic-affinity measurements, and competition-based phosphorylation assays to establish that for HK, MtrB autophosphorylation occurs in cis , similar to what has been proposed for the PhoR and PrrB HKs...
June 27, 2018: MSphere
Nicky McCreesh, Richard G White
We currently have little idea where Mycobacterium tuberculosis (Mtb) transmission occurs in high incidence settings. Molecular studies suggest that only around 8-19% of transmission to adults occurs within-household, or between known social-contacts. This contrasts with findings from social-contact studies, which show that substantial proportions of contact time occur in households, workplaces and schools. A mathematical model of social-contact behaviour and Mtb transmission was developed, incorporating variation in susceptibility and infectiousness...
March 29, 2018: Scientific Reports
Hester Korthals Altes, Serieke Kloet, Frank Cobelens, Martin Bootsma
While tuberculosis (TB) represents a significant disease burden worldwide, low-incidence countries strive to reach the WHO target of pre-elimination by 2035. Screening for TB in immigrants is an important component of the strategy to reduce the TB burden in low-incidence settings. An important option is the screening and preventive treatment of latent TB infection (LTBI). Whether this policy is worthwhile depends on the extent of transmission within the country, and introduction of new cases through import...
2018: PloS One
Soyoung Kim, Aurelio A de Los Reyes, Eunok Jung
Tuberculosis (TB) is the sixth leading cause of morbidity and mortality in the Philippines. Although significant progress has been made in the detection and cure of TB under the Directly Observed Treatment Short Course, battling against the disease is still a burdensome task. It demands a concerted effort for specific and effective interventions. In this work, a mathematical TB model fitted to the Philippine data is developed to understand its transmission dynamics. Different control strategies such as distancing, latent case finding, case holding, active case finding controls, and combinations thereof are investigated within the framework of optimal control theory...
April 14, 2018: Journal of Theoretical Biology
Joseph M Cicchese, Elsje Pienaar, Denise E Kirschner, Jennifer J Linderman
Introduction: Tuberculosis (TB), one of the most common infectious diseases, requires treatment with multiple antibiotics taken over at least 6 months. This long treatment often results in poor patient-adherence, which can lead to the emergence of multi-drug resistant TB. New antibiotic treatment strategies are sorely needed. New antibiotics are being developed or repurposed to treat TB, but as there are numerous potential antibiotics, dosing sizes and potential schedules, the regimen design space for new treatments is too large to search exhaustively...
December 2017: Cellular and Molecular Bioengineering
Leigh F Johnson, Margaret T May, Rob E Dorrington, Morna Cornell, Andrew Boulle, Matthias Egger, Mary-Ann Davies
BACKGROUND: Substantial reductions in adult mortality have been observed in South Africa since the mid-2000s, but there has been no formal evaluation of how much of this decline is attributable to the scale-up of antiretroviral treatment (ART), as previous models have not been calibrated to vital registration data. We developed a deterministic mathematical model to simulate the mortality trends that would have been expected in the absence of ART, and with earlier introduction of ART. METHODS AND FINDINGS: Model estimates of mortality rates in ART patients were obtained from the International Epidemiology Databases to Evaluate AIDS-Southern Africa (IeDEA-SA) collaboration...
December 2017: PLoS Medicine
Anthony T Fojo, Emily A Kendall, Parastu Kasaie, Sourya Shrestha, Thomas A Louis, David W Dowdy
Background: Mathematical models are increasingly used to understand the dynamics of infectious diseases, including "chronic" infections with long generation times. Such models include features that are obscure to most clinicians and decision-makers. Methods: Using a model of a hypothetical active case-finding intervention for tuberculosis in India as an example, we illustrate the effects on model results of different choices for model structure, input parameters, and calibration process...
2017: Open Forum Infectious Diseases
Eduardo Ibarguen-Mondragon, Lourdes Esteva, Edith Mariela Burbano-Rosero
In this work we formulate a model for the population dynamics of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB). Our main interest is to assess the impact of the competition among bacteria on the infection prevalence. For this end, we assume that Mtb population has two types of growth. The first one is due to bacteria produced in the interior of each infected macrophage, and it is assumed that is proportional to the number of infected macrophages. The second one is of logistic type due to the competition among free bacteria released by the same infected macrophages...
April 1, 2018: Mathematical Biosciences and Engineering: MBE
Surabhi Pandey, Ezio Venturino
Tuberculosis (TB) is returning to be a worldwide global public health threat. It is estimated that 9.6 million cases occurred in 2014, of which just two-thirds notified to public health authorities. The "missing cases" constitute a severe challenge for TB transmission control. TB is a severe disease in India, while, worldwide, the WHO estimates that one third of the entire world population is infected. Nowadays, incidence estimation relies increasingly more on notifications of new cases from routine surveillance...
February 1, 2018: Mathematical Biosciences and Engineering: MBE
Jūlija Pečerska, James Wood, Mark M Tanaka, Tanja Stadler
This chapter reviews the use of mathematical and computational models to facilitate understanding of the epidemiology and evolution of Mycobacterium tuberculosis. First, we introduce general epidemiological models, and describe their use with respect to epidemiological dynamics of a single strain and of multiple strains of M. tuberculosis. In particular, we discuss multi-strain models that include drug sensitivity and drug resistance. Second, we describe models for the evolution of M. tuberculosis within and between hosts, and how the resulting diversity of strains can be assessed by considering the evolutionary relationships among different strains...
2017: Advances in Experimental Medicine and Biology
Saif Khan, Pallavi Somvanshi, Tulika Bhardwaj, Raju K Mandal, Sajad A Dar, Mohd Wahid, Arshad Jawed, Mohtashim Lohani, Mahvish Khan, Mohammed Y Areeshi, Shafiul Haque
The emergence of multi-drug resistant strains and co-occurrence of tuberculosis with HIV creates a major burden to the human health globally. Failure of primary antibacterial therapy necessitates the identification of new mycobacterial drugs. In this study, a comprehensive analysis involving bottom-up systems biology approach was applied wherein we have identified potential therapeutic targets of Mycobacterium tuberculosis infections. Our study prioritized M. tuberculosis therapeutic targets (aspartate-β-semialdeyhde dehydrogenase [ASD], dihydrodipicolinate reductase and diaminopimelate decarboxylase) based on flux and elementary mode analysis using direct mathematical modeling of the relevant metabolic pathways...
March 2018: Journal of Cellular Biochemistry
Charlotte Genestet, Florence Ader, Catherine Pichat, Gérard Lina, Oana Dumitrescu, Sylvain Goutelle
While isoniazid and rifampin have been the cornerstone of tuberculosis therapy caused by drug-susceptible Mycobacterium tuberculosis for more than 40 years, their combined action has never been thoroughly assessed by modern quantitative pharmacology approaches. The aims of this work were to perform in vitro experiments and mathematical modeling of the antibacterial effect of isoniazid and rifampin alone and in combination against various strains of Mycobacterium tuberculosis After MIC determination of H37Rv and three strains belonging to the Beijing, Euro-American, and Indo-Oceanic lineages, the antibacterial effects of isoniazid and rifampin alone and in combination were studied in static time-kill experiments...
January 2018: Antimicrobial Agents and Chemotherapy
Yu Zhao, Mingtao Li, Sanling Yuan
Tuberculosis (TB), an air-borne infectious disease, is a major public-health problem in China. The reported number of the active tuberculosis cases is about one million each year. The morbidity data for 2005-2012 reflect that the difference in morbidity based on age group is significant, thus the role of age-structure on the transmission of TB needs to be further developed. In this work, based on the reported data and the observed morbidity characteristics, we propose a susceptible-exposed-infectious-recovered (SEIR) epidemic model with age groupings, involving three categories: children, the middle-aged, and senior to investigate the role of age on the transmission of tuberculosis in Mainland China from 2005 to 2016...
October 7, 2017: International Journal of Environmental Research and Public Health
Ana Dias, Rita Gaio, Pedro Sousa, Marta Gomes, Olena Oliveira, Raquel Duarte
INTRODUCTION: Tuberculosis notification in Portugal has decreased in the last few years. As a consequence of the economic crisis, emigration has increased and immigration has decreased. Immigrants are a risk group for tuberculosis. Most emigrants are 20-44 years old and belong to the age group most affected by tuberculosis. OBJECTIVE: To describe the decrease in tuberculosis notification in Portugal over the last years from a demographical point of view. METHODS: Mathematical analysis was performed to quantify the effect of the migration movements (separately and simultaneously) on tuberculosis notification in Portugal from 2008 to 2014...
January 2018: Archivos de Bronconeumología
Martina Cantone, Guido Santos, Pia Wentker, Xin Lai, Julio Vera
Even today two bacterial lung infections, namely pneumonia and tuberculosis, are among the 10 most frequent causes of death worldwide. These infections still lack effective treatments in many developing countries and in immunocompromised populations like infants, elderly people and transplanted patients. The interaction between bacteria and the host is a complex system of interlinked intercellular and the intracellular processes, enriched in regulatory structures like positive and negative feedback loops. Severe pathological condition can emerge when the immune system of the host fails to neutralize the infection...
2017: Frontiers in Physiology
D Zenner, H Hafezi, J Potter, S Capone, A Matteelli
With the advent of the World Health Organization End TB strategy, there has been renewed interest in screening for active tuberculosis (TB), and particularly latent tuberculous infection (LTBI). In low-incidence countries, a high proportion of TB cases are notified among migrants, which often occurs due to LTBI reactivation. We aimed to review the effectiveness and cost-effectiveness of screening migrants for active TB LTBI to inform and support the TB elimination strategy in low-incidence countries. We carried out a narrative review of English language articles published between 1 January 2000 and 31 June 2016 using the PubMed database...
September 1, 2017: International Journal of Tuberculosis and Lung Disease
D Pedrazzoli, D Boccia, P J Dodd, K Lönnroth, D W Dowdy, A Siroka, M E Kimerling, R G White, R M G J Houben
INTRODUCTION: Despite the close link between tuberculosis (TB) and poverty, most mathematical models of TB have not addressed underlying social and structural determinants. OBJECTIVE: To review studies employing mathematical modelling to evaluate the epidemiological impact of the structural determinants of TB. METHODS: We systematically searched PubMed and personal libraries to identify eligible articles. We extracted data on the modelling techniques employed, research question, types of structural determinants modelled and setting...
September 1, 2017: International Journal of Tuberculosis and Lung Disease
Peter J Dodd, Courtney M Yuen, Charalambos Sismanidis, James A Seddon, Helen E Jenkins
BACKGROUND: Tuberculosis in children is increasingly recognised as an important component of the global tuberculosis burden, with an estimated 1 million cases in 2015. Although younger children are vulnerable to severe forms of tuberculosis disease, no age-disaggregated estimates of paediatric tuberculosis mortality exist, and tuberculosis has never been included in official estimates of under-5 child mortality. We aimed to produce a global mortality burden estimate in children using a complementary approach not dependent on vital registration data...
September 2017: Lancet Global Health
Dianbo Liu, Luca Albergante, Timothy J Newman
Using a combination of mathematical modelling, statistical simulation and large-scale data analysis we study the properties of linear regulatory chains (LRCs) within gene regulatory networks (GRNs). Our modelling indicates that downstream genes embedded within LRCs are highly insulated from the variation in expression of upstream genes, and thus LRCs act as attenuators. This observation implies a progressively weaker functionality of LRCs as their length increases. When analyzing the preponderance of LRCs in the GRNs of Escherichia coli K12 and several other organisms, we find that very long LRCs are essentially absent...
July 7, 2017: Nucleic Acids Research
Romain Ragonnet, James M Trauer, Justin T Denholm, Ben J Marais, Emma S McBryde
Multidrug-resistant and rifampicin-resistant tuberculosis (MDR/RR-TB) represent an important challenge for global tuberculosis (TB) control. The high rates of MDR/RR-TB observed among re-treatment cases can arise from diverse pathways: de novo amplification during initial treatment, inappropriate treatment of undiagnosed MDR/RR-TB, relapse despite appropriate treatment, or reinfection with MDR/RR-TB. Mathematical modelling allows quantification of the contribution made by these pathways in different settings...
May 30, 2017: BMC Infectious Diseases
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"