scholarly journals Cross-Kingdom Cell-to-Cell Interactions in Cariogenic Biofilm Initiation

2020 ◽  
Vol 100 (1) ◽  
pp. 74-81
Author(s):  
S.X. Wan ◽  
J. Tian ◽  
Y. Liu ◽  
A. Dhall ◽  
H. Koo ◽  
...  
Keyword(s):  
Single Cell ◽  
Early Stage ◽  
Subsequent Development ◽  
Cell Interaction ◽  
Force Microscopy ◽  
Direct Cell ◽  
Binding Forces ◽  
Biofilm Development ◽  
Biophysical Aspect ◽  
Cariogenic Biofilm

Candida albicans is known to form polymicrobial biofilms with various Streptococcus spp., including mitis and mutans group streptococci. Streptococcus gordonii (mitis group) has been shown to bind avidly to C. albicans hyphae via direct cell-to-cell interaction, while the cariogenic pathogen Streptococcus mutans (mutans group) interacts with the fungal cells via extracellular glucans. However, the biophysical properties of these cross-kingdom interactions at the single-cell level during the early stage of biofilm formation remain understudied. Here, we examined the binding forces between S. mutans (or S. gordonii) and C. albicans in the presence and absence of in situ glucans on the fungal surface using single-cell atomic force microscopy and their influence on biofilm initiation and subsequent development under cariogenic conditions. The data show that S. gordonii binding force to the C. albicans surface is significantly higher than that of S. mutans to the fungal surface (~2-fold). However, S. mutans binding forces are dramatically enhanced when the C. albicans cell surface is locally coated with extracellular glucans (~6-fold vs. uncoated C. albicans), which vastly exceeds the forces between S. gordonii and C. albicans. The enhanced binding affinity of S. mutans to glucan-coated C. albicans resulted in a larger structure during early biofilm initiation compared to S. gordonii–C. albicans biofilms. Ultimately, this resulted in S. mutans dominance composition in the 3-species biofilm model under cariogenic conditions. This study provides a novel biophysical aspect of Candida-streptococcal interaction whereby extracellular glucans may selectively favor S. mutans binding interactions with C. albicans during cariogenic biofilm development.

scholarly journals Sequential fate-switches in stem-like cells drive the tumorigenic trajectory from human neural stem cells to malignant glioma

Cell Research ◽  
2021 ◽  
Author(s):  
Xiaofei Wang ◽  
Ran Zhou ◽  
Yanzhen Xiong ◽  
Lingling Zhou ◽  
Xiang Yan ◽  
...  
Keyword(s):  
Malignant Glioma ◽  
Single Cell ◽  
De Novo ◽  
Early Stage ◽  
Lineage Tracing ◽  
Human Neural Stem Cells ◽  
Transcriptional Reprogramming ◽  
Neural Stem Progenitor Cells ◽  
Human Gbm ◽  
End Stage

AbstractGlioblastoma (GBM) is an incurable and highly heterogeneous brain tumor, originating from human neural stem/progenitor cells (hNSCs/hNPCs) years ahead of diagnosis. Despite extensive efforts to characterize hNSCs and end-stage GBM at bulk and single-cell levels, the de novo gliomagenic path from hNSCs is largely unknown due to technical difficulties in early-stage sampling and preclinical modeling. Here, we established two highly penetrant hNSC-derived malignant glioma models, which resemble the histopathology and transcriptional heterogeneity of human GBM. Integrating time-series analyses of whole-exome sequencing, bulk and single-cell RNA-seq, we reconstructed gliomagenic trajectories, and identified a persistent NSC-like population at all stages of tumorigenesis. Through trajectory analyses and lineage tracing, we showed that tumor progression is primarily driven by multi-step transcriptional reprogramming and fate-switches in the NSC-like cells, which sequentially generate malignant heterogeneity and induce tumor phenotype transitions. We further uncovered stage-specific oncogenic cascades, and among the candidate genes we functionally validated C1QL1 as a new glioma-promoting factor. Importantly, the neurogenic-to-gliogenic switch in NSC-like cells marks an early stage characterized by a burst of oncogenic alterations, during which transient AP-1 inhibition is sufficient to inhibit gliomagenesis. Together, our results reveal previously undercharacterized molecular dynamics and fate choices driving de novo gliomagenesis from hNSCs, and provide a blueprint for potential early-stage treatment/diagnosis for GBM.

scholarly journals Quality control of direct cell–mineral adhesion measurements in air and liquid using inverse AFM imaging

RSC Advances ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 5384-5392
Author(s):  
Abd Alaziz Abu Quba ◽  
Gabriele E. Schaumann ◽  
Mariam Karagulyan ◽  
Doerte Diehl
Keyword(s):  
Quality Control ◽  
Single Cell ◽  
Single Cell Level ◽  
Cell Level ◽  
C Cell ◽  
Afm Imaging ◽  
Direct Cell ◽  
Mineral Interaction

Setup for a reliable cell-mineral interaction at the single-cell level, (a) study of the mineral by a sharp tip, (b) study of the bacterial modified probe by a characterizer, (c) cell-mineral interaction, (d) subsequent check of the modified probe.

Sequence of Colonization Determines the Composition of Mixed Biofilms by Escherichia coli O157:H7 and O111:H8 Strains†

2015 ◽  
Vol 78 (8) ◽  
pp. 1554-1559 ◽  
Author(s):  
RONG WANG ◽  
NORASAK KALCHAYANAND ◽  
JAMES L. BONO
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Early Stage ◽  
Critical Role ◽  
The United States ◽  
Food Samples ◽  
E Coli ◽  
Cell Percentage ◽  
Composition And Structure ◽  
Biofilm Development

Bacterial biofilms are one of the potential sources of cross-contamination in food processing environments. Shiga toxin–producing Escherichia coli (STEC) O157:H7 and O111:H8 are important foodborne pathogens capable of forming biofilms, and the coexistence of these two STEC serotypes has been detected in various food samples and in multiple commercial meat plants throughout the United States. Here, we investigated how the coexistence of these two STEC serotypes and their sequence of colonization could affect bacterial growth competition and mixed biofilm development. Our data showed that E. coli O157:H7 strains were able to maintain a higher cell percentage in mixed biofilms with the co-inoculated O111:H8 companion strains, even though the results of planktonic growth competition were strain dependent. On solid surfaces with preexisting biofilms, the sequence of colonization played a critical role in determining the composition of the mixed biofilms because early stage precolonization significantly affected the competition results between the E. coli O157:H7 and O111:H8 strains. The precolonizer of either serotype was able to outgrow the other serotype in both planktonic and biofilm phases. The competitive interactions among the various STEC serotypes would determine the composition and structure of the mixed biofilms as well as their potential risks to food safety and public health, which is largely influenced by the dominant strains in the mixtures. Thus, the analysis of mixed biofilms under various conditions would be of importance to determine the nature of mixed biofilms composed of multiple microorganisms and to help implement the most effective disinfection operations accordingly.

scholarly journals The Role of Methyl Groups in the Early Stage of Thermal Polymerization of Polycyclic Aromatic Hydrocarbons Revealed by Molecular Imaging

2020 ◽  
Author(s):  
Pengcheng Chen ◽  
Shadi Fatayer ◽  
Bruno Schuler ◽  
Jordan N. Metz ◽  
Leo Gross ◽  
...  
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Early Stage ◽  
Complex Mixture ◽  
Thermal Polymerization ◽  
Industrial Applications ◽  
Thermal Reactions ◽  
Force Microscopy ◽  
Wide Range ◽  
Polycyclic Aromatic

The initial thermal reactions of aromatic hydrocarbons are relevant to many industrial applications. However, tracking the growing number of heavy polycyclic aromatic hydrocarbon (PAH) products is extremely challenging because many reactions are unfolding in parallel from a mixture of molecules. Herein, we studied the reactions of 2,7-dimethylpyrene (DMPY) to decipher the roles of methyl substituents during mild thermal treatment. We found that the presence of methyl substituents is key for reducing the thermal severity required to initiate chemical reactions in natural molecular mixtures. A complex mixture of thermal products including monomers, dimers, and trimers were characterized by NMR, mass spectrometry and non-contact atomic force microscopy (nc-AFM). A wide range of structural transformations including methyl transfer and polymerization reactions were identified. A detailed mechanistic understanding was obtained on the roles of H radicals during the polymerization of polycyclic aromatic hydrocarbons.

scholarly journals Establishing correlation of axial and vertical force of cardiac artificial tissue using a novel micromachined sensor

2020 ◽  
Author(s):  
Angelo Gaitas ◽  
Francesca Stillitano ◽  
Irene Turnbull
Keyword(s):  
Single Cell ◽  
Axial Force ◽  
Cardiac Tissue ◽  
Heart Function ◽  
Heart Tissue ◽  
Vertical Force ◽  
Force Microscopy ◽  
Artificial Tissue ◽  
One Step ◽  
Engineered Tissue

AbstractCardiomyocytes iPSC (iPSC-CMs) have great potential for cell therapy, drug assessment, and for understanding the pathophysiology and genetic underpinnings of cardiac diseases. Contraction forces are one of the most important characteristics of cardiac function and are predictors of healthy and diseased states. Cantilever techniques, such as atomic force microscopy, measure the vertical force of a single cell, while systems designed to more closely resemble the physical heart function, such as cardiac tissue on posts, measure the axial force. One important question is how do these two force measurements correlate? By establishing a correlation of the axial and vertical force we will be one step closer in being able to use single cell iPSC instead of more elaborate human engineered tissue or animal heart tissue as models. A novel micromachined sensor for measuring force contractions of artificial tissue has been developed. Using this novel sensor a correlation between axial force and vertical force is experimentally established. This finding supports the use of vertical measurements as an alternative to tissue measurements.

scholarly journals Draft Genome Sequences of Two Veillonella tobetsuensis Clinical Isolates from Intraoperative Bronchial Fluids of Elderly Patients with Pulmonary Carcinoma

2019 ◽  
Vol 8 (38) ◽  
Author(s):  
Izumi Mashima ◽  
Tohru Miyoshi-Akiyama ◽  
Junko Tomida ◽  
Ryo Kutsuna ◽  
Jumpei Washio ◽  
...  
Keyword(s):  
Elderly Patients ◽  
Early Stage ◽  
Draft Genome ◽  
Clinical Isolates ◽  
Genome Sequences ◽  
Oral Biofilm ◽  
Content Type ◽  
Pulmonary Carcinoma ◽  
Biofilm Development

To date, Veillonella tobetsuensis has been known as an oral anaerobe and a facilitator of early-stage oral biofilm development with streptococci. Here, we report the draft genome sequences of 2 strains of V. tobetsuensis first isolated from intraoperative bronchial fluids of elderly patients with pulmonary carcinoma.

Sign in / Sign up

Export Citation Format

Share Document