Search results for "Rule"

Weakly coupled map lattice models for multicellular patterning and collective normalization of abnormal single-cell states

2017

We present a weakly coupled map lattice model for patterning that explores the effects exerted by weakening the local dynamic rules on model biological and artificial networks composed of two-state building blocks (cells). To this end, we use two cellular automata models based on: (i) a smooth majority rule (model I) and (ii) a set of rules similar to those of Conway's Game of Life (model II). The normal and abnormal cell states evolve according with local rules that are modulated by a parameter $\kappa$. This parameter quantifies the effective weakening of the prescribed rules due to the limited coupling of each cell to its neighborhood and can be experimentally controlled by appropriate e…

Virulence of Streptococcus mutans: An intrafamilial cohort study on transmission of genotypes

2020

Background The main aims of this cohort study were to measure the intrafamilial risk of transmission, sharing and stability of the most virulent S. mutans genotypes. Material and Methods A total of 392 clinical isolates of S. mutans obtained from caries-active adults and genotyped to evaluate their transmissibility over time. After extraction of the chromosomal DNA, PCR were performed to detect the genes involved in the production of GbpA (gbpA) and mutacin types I, II, III and IV (mutAI, mutAII, mutAIII and mutAIV). Results The gbpA, mutAI, mutAII, mutAIII and mutAIV genes were detected in 77.3, 12.5, 51, 16.6 and 89.8% of S. mutans isolates, respectively. The virulence of S. mutans was as…

Precision and accuracy of single-molecule FRET measurements-a multi-laboratory benchmark study

2018

Single-molecule Forster resonance energy transfer (smFRET) is increasingly being used to determine distances, structures, and dynamics of biomolecules in vitro and in vivo. However, generalized protocols and FRET standards to ensure the reproducibility and accuracy of measurements of FRET efficiencies are currently lacking. Here we report the results of a comparative blind study in which 20 labs determined the FRET efficiencies (E) of several dye-labeled DNA duplexes. Using a unified, straightforward method, we obtained FRET efficiencies with s.d. between +/- 0.02 and +/- 0.05. We suggest experimental and computational procedures for converting FRET efficiencies into accurate distances, and…

Bacterial Biofilm Inhibition in the Development of Effective Anti-Virulence Strategy

2018

There is an urgent need for new therapeutic strategies to counteract the global threat of antibiotic resistance, which has become, in recent years, one of the major public health concern. An important contribution to the microbial survival in hostile environments has been given by the capability of pathogens to form sessile communities able to adhere to biotic or abiotic surfaces, known as biofilms.

On the structural connectivity of large-scale models of brain networks at cellular level

2021

AbstractThe brain’s structural connectivity plays a fundamental role in determining how neuron networks generate, process, and transfer information within and between brain regions. The underlying mechanisms are extremely difficult to study experimentally and, in many cases, large-scale model networks are of great help. However, the implementation of these models relies on experimental findings that are often sparse and limited. Their predicting power ultimately depends on how closely a model’s connectivity represents the real system. Here we argue that the data-driven probabilistic rules, widely used to build neuronal network models, may not be appropriate to represent the dynamics of the …

Mandarin essential oils inhibit quorum sensing and virulence factors of Pseudomonas aeruginosa

2016

Pseudomonas aeruginosa produces biofilm and several virulence factors coordinated by quorum sensing (QS) in food. The interruption of QS is a target to control the bacterial virulence. Chemical preservatives used to control biofilm give rise to several food safety problems. For this reason, essential oils (EOs), generally recognized as safe products, are a hopeful alternative. The aim of this work was to determine the chemical composition of mandarin EOs obtained by cold-pressing (EOP) and cold-pressing followed by steam distillation (EOPD) and their antipathogenic properties against P. aeruginosa. Both EOs contained the highest quantities of monoterpene hydrocarbons, mainly limonene, follo…

The influence of microorganisms in allergic diseases.

2017

Mode of Action Analyses of Neferine, a Bisbenzylisoquinoline Alkaloid of Lotus (Nelumbo nucifera) against Multidrug-Resistant Tumor Cells

2017

Neferine, a bisbenzylisoquinoline alkaloid isolated from the green seed embryos of Lotus (Nelumbo nucifera Gaertn), has been previously shown to have various anti-cancer effects. In the present study, we evaluated the effect of neferine in terms of P-glycoprotein (P-gp) inhibition via in vitro cytotoxicity assays, R123 uptake assays in drug-resistant cancer cells, in silico molecular docking analysis on human P-gp and in silico absorption, distribution, metabolism, and excretion (ADME), quantitative structure activity relationships (QSAR) and toxicity analyses. Lipinski rule of five were mainly considered for the ADME evaluation and the preset descriptors including number of hydrogen bond d…

Yersiniaspp. in Wild Rodents and Shrews in Finland

2017

Yersinia enterocolitica and Yersinia pseudotuberculosis are important zoonotic bacteria causing human enteric yersiniosis commonly reported in Europe. All Y. pseudotuberculosis strains are considered pathogenic, while Y. enterocolitica include both pathogenic and nonpathogenic strains which can be divided into six biotypes (1A, 1B, and 2-5) and about 30 serotypes. The most common types causing yersiniosis in Europe are Y. enterocolitica bioserotypes 4/O:3 and 2/O:9. Strains belonging to biotype 1A are considered as nonpathogenic because they are missing important virulence genes like the attachment-invasion-locus (ail) gene in the chromosome and the virulence plasmid. The role of wild small…

Extra-Intestinal Fluoroquinolone-Resistant Escherichia coli Strains Isolated from Meat

2018

Extra-intestinal E. coli are emerging as a global threat due to their diffusion as opportunistic pathogens and, above all, to their wide set of antibiotic resistance determinants. There are still many gaps in our knowledge of their origin and spread pathways, although food animals have been adjudicated vehicles for passing mult-drug resistant bacteria to humans. This study analyzed 46 samples of meat purchased from retail stores in Palermo in order to obtain quinolone-resistant E. coli isolates. Strains were screened for their phylogenetic groups, ST131-associated single nucleotide polymorphisms (SNPs), and then typed by ERIC-PCR. Their set of virulence factors, namely, kpsMII, papA, sfaS, …