scholarly journals Moving microbes: the dynamics of transient microbial residence on human skin

2019 ◽  
Author(s):  
Roo Vandegrift ◽  
Ashkaan K. Fahimipour ◽  
Mario Muscarella ◽  
Ashley C. Bateman ◽  
Kevin Van Den Wymelenberg ◽  
...  
Keyword(s):  
Human Skin ◽  
Control Strategies ◽  
Skin Microbiome ◽  
Transient Effects ◽  
Plant Leaves ◽  
Short Term ◽  
Microbiome Composition ◽  
Skin Contact ◽  
Short Time ◽  
Lower Biomass

AbstractThe human skin microbiome interacts intimately with human health, yet the drivers of skin microbiome composition and diversity are not well-understood. The composition of the skin microbiome has been characterized as both highly variable and relatively stable, depending on the time scale under consideration, and it is not clear what role contact with environmental sources of microbes plays in this variability. We experimentally mimicked human skin contact with two common environmental sources of microorganisms — soils and plant leaves — and characterized the dynamics of microbial acquisition and persistence on skin on very short time scales. Repeatable changes in skin community composition following encounters with environmental sources were observed, and these trajectories largely depend on donor community biomass distributions. Changes in composition persisted for at least 24 hours and through a soap and water wash following exposures to relatively high biomass soil communities. In contrast, exposures to lower biomass leaf communities were undetectable after a 24 hour period. Absolute abundances of bacterial taxa in source communities predicted transmission probabilities and residence times, independent of phylogenetic considerations. Our results suggest that variability in the composition of the skin microbiome can be driven by transient encounters with common environmental sources, and that these relatively transient effects can persist when the source is of sufficient biomass.ImportanceHumans come into contact with environmental sources of microbes, such as soil or plants, constantly. Those microbial exposures have been linked to health through training and modulation of the immune system. While much is known about the human skin microbiome, the short term dynamics after a contact event, such as touching soil, have not been well characterized. In this study, we examine what happens after such a contact event, describing trends in microbial transmission to and persistence on the skin. Additionally, we use computational sampling model simulations to interrogate null expectations for these kinds of experiments. This work has broad implications for infection control strategies and therapeutic techniques that rely on modification of the microbiome, such as probiotics and faecal transplantation.

scholarly journals New Insights into the Intrinsic and Extrinsic Factors That Shape the Human Skin Microbiome

mBio ◽  
2019 ◽  
Vol 10 (4) ◽  
Author(s):  
Pedro A. Dimitriu ◽  
Brandon Iker ◽  
Kausar Malik ◽  
Hilary Leung ◽  
W. W. Mohn ◽  
...  
Keyword(s):  
Human Skin ◽  
North American ◽  
Skin Aging ◽  
Physiological Parameters ◽  
Host Factors ◽  
Chronological Age ◽  
Skin Microbiome ◽  
Physiological Factors ◽  
Modeling Tools ◽  
Microbiome Composition

ABSTRACT Despite recognition that biogeography and individuality shape the function and composition of the human skin microbiome, we know little about how extrinsic and intrinsic host factors influence its composition. To explore the contributions of these factors to skin microbiome variation, we profiled the bacterial microbiomes of 495 North American subjects (ages, 9 to 78 years) at four skin surfaces plus the oral epithelium using 16S rRNA gene amplicon sequencing. We collected subject metadata, including host physiological parameters, through standardized questionnaires and noninvasive biophysical methods. Using a combination of statistical modeling tools, we found that demographic, lifestyle, and physiological factors collectively explained 12 to 20% of the variability in microbiome composition. The influence of health factors was strongest on the oral microbiome. Associations between host factors and the skin microbiome were generally dominated by operational taxonomic units (OTUs) affiliated with the Clostridiales and Prevotella. A subset of the correlations between microbial features and host attributes were site specific. To further explore the relationship between age and the skin microbiome of the forehead, we trained a Random Forest regression model to predict chronological age from microbial features. Age was associated mostly with two mutually coexcluding Corynebacterium OTUs. Furthermore, skin aging variables (wrinkles and hyperpigmented spots) were independently correlated to these taxa. IMPORTANCE Many studies have highlighted the importance of body site and individuality in shaping the composition of the human skin microbiome, but we still have a poor understanding of how extrinsic (e.g., lifestyle) and intrinsic (e.g., age) factors influence its composition. We characterized the bacterial microbiomes of North American volunteers at four skin sites and the mouth. We also collected extensive subject metadata and measured several host physiological parameters. Integration of host and microbial features showed that the skin microbiome was predominantly associated with demographic, lifestyle, and physiological factors. Furthermore, we uncovered reproducible associations between chronological age, skin aging, and members of the genus Corynebacterium. Our work provides new understanding of the role of host selection and lifestyle in shaping skin microbiome composition. It also contributes to a more comprehensive appreciation of the factors that drive interindividual skin microbiome variation.

Effect of short-term use of oral contraceptive pills on intraocular pressure

2020 ◽  
Vol 35 (3) ◽  
Author(s):  
Tayyaba Gul Malik ◽  
Hina Nadeem ◽  
Eiman Ayesha ◽  
Rabail Alam
Keyword(s):  
Oral Contraceptive ◽  
Childbearing Age ◽  
Short Term ◽  
Oral Contraceptive Pills ◽  
Contraceptive Pills ◽  
Time Period ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
Short Time

Objective: To study the effect of short-term use of oral contraceptive pills on intra-ocular pressures of women of childbearing age.   Methods: It was a comparative observational study, conducted at Arif memorial teaching hospital and Allied hospital Faisalabad for a period of six months. Hundred female subjects were divided into two groups of 50 each. Group A, included females, who had been taking oral contraceptive pills (OCP) for more than 6 months and less than 36 months. Group B, included 50 age-matched controls, who had never used OCP. Ophthalmic and systemic history was taken. Careful Slit lamp examination was performed and intraocular pressures (IOP) were measured using Goldman Applanation tonometer. Fundus examination was done to rule out any posterior segment disease. After collection of data, we analyzed and compared the intra ocular pressures between the two groups by using ANOVA in SPSS version 21.   Results: Average duration of using OCP was 14.9 months. There was no significant difference of Cup to Disc ratios between the two groups (p= 0.109). However, significant difference was noted between the IOP of OCP group and controls. (p=0.000). Conclusion: OCP significantly increase IOP even when used for short time period.

scholarly journals Evaluating Metagenomic Analysis for Pathogen Transmission in Healthcare Settings

2020 ◽  
Vol 41 (S1) ◽  
pp. s224-s224
Author(s):  
Curt Hewitt ◽  
Katharina Weber ◽  
Danielle LeSassier ◽  
Anthony Kappell ◽  
Kathleen Schulte ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Dna Analysis ◽  
Pathogen Transmission ◽  
Species Level ◽  
Metagenomic Analysis ◽  
Skin Microbiome ◽  
Limited Information ◽  
Culture Methods ◽  
Data Set ◽  
Skin Contact

Background: The prevalence of healthcare-acquired infections (HAIs) and rising levels of antimicrobial resistance place a significant burden on modern healthcare systems. Cultures are typically used to track HAIs; however, culture methods provide limited information and are not applicable to all pathogens. Next-generation sequencing (NGS) can detect and characterize pathogens present within a sample, but few research studies have explored how NGS could be used to detect pathogen transmission events under HAI-relevant scenarios. The objective of this CDC-funded project was to evaluate and correlate sequencing approaches for pathogen transmission with standard culture-based analysis. Methods: We modeled pathogen transfer via hand contact using synthetic skin. These skin coupons were seeded with a community of commensal organisms to mimic the human skin microbiome. Pathogens were added at physiologically relevant high or low levels prior to skin-to-skin contact. The ESKAPE pathogens: E. faecium, S. aureus, K. pneumoniae, A. baumannii, P. aeruginosa, and Enterobacter spp plus C. difficile were employed because they are the most common antibiotic resistant HAIs. Pathogen transfer between skin coupons was measured following direct skin contact and fomite surface transmission. The effects of handwashing or fomite decontamination were also evaluated. Transferred pathogens were enumerated via culture to establish a robust data set against which DNA and RNA sequence analyses of the same samples could be compared. These data also provide a quantitative assessment of individual ESKAPE+C pathogen transfer rates in skin contact scenarios. Results: Metagenomic and metatranscriptomic analysis using custom analysis pipelines and reference databases successfully identified the commensal and pathogenic organisms present in each sample at the species level. This analysis also identified antibiotic resistance genes and plasmids. Metatranscriptomic analysis permitted not only gene identification but also confirmation of gene expression, a critical factor in the evaluation of antibiotic resistance. DNA analysis does not require cell viability, a key differentiator between sequencing and culturing reflected in simulated handwashing data. Sensitivity remains a key limitation of metagenomic analysis, as shown by the poor species identification and gene content characterization of pathogens present at low abundance within the simulated microbial community. Species level identification typically failed as ratios fell below 1:1,000 pathogen CFU:total community CFU. Conclusions: These findings demonstrate the strengths and weaknesses of NGS for molecular epidemiology. The data sets produced for this study are publicly available so they can be employed for future metagenomic benchmarking studies.Funding: NoneDisclosures: None

scholarly journals Effects of white Gaussian noise on dynamic balance in healthy young adults

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ziyou Zhou ◽  
Can Wu ◽  
Zhen Hu ◽  
Yujuan Chai ◽  
Kai Chen ◽  
...  
Keyword(s):  
Young Adults ◽  
Gaussian Noise ◽  
Center Of Pressure ◽  
Dynamic Balance ◽  
White Gaussian Noise ◽  
Fluctuation Analysis ◽  
Balance Performance ◽  
Short Term ◽  
Crossover Point ◽  
Short Time

AbstractIt has been known that short-time auditory stimulation can contribute to the improvement of the balancing ability of the human body. The present study aims to explore the effects of white Gaussian noise (WGN) of different intensities and frequencies on dynamic balance performance in healthy young adults. A total of 20 healthy young participants were asked to stand at a dynamic balance force platform, which swung along the x-axis with an amplitude of ± 4° and frequency of 1 Hz. Their center of pressure (COP) trajectories were recorded when they were stimulated by WGN of different intensities (block 1) and different frequencies (block 2). A traditional method and detrended fluctuation analysis (DFA) were used for data preprocessing. The authors found that only with 75–85 dB WGN, the COP parameters improved. WGN frequency did not affect the dynamic balance performance of all the participants. The DFA results indicated stimulation with 75 dB WGN enhanced the short-term index and reduced the crossover point. Stimulation with 500 Hz and 2500 Hz WGN significantly enhanced the short-term index. These results suggest that 75 dB WGN and 500 Hz and 2500 Hz WGN improved the participants’ dynamic balance performance. The results of this study indicate that a certain intensity of WGN is indispensable to achieve a remarkable improvement in dynamic balance. The DFA results suggest that WGN only affected the short-term persistence, indicating the potential of WGN being considered as an adjuvant therapy in low-speed rehabilitation training.

scholarly journals SkinBug: an artificial intelligence approach to predict human skin microbiome-mediated metabolism of biotics and xenobiotics

iScience ◽  
2021 ◽  
Vol 24 (1) ◽  
pp. 101925
Author(s):  
Shubham K. Jaiswal ◽  
Shitij Manojkumar Agarwal ◽  
Parikshit Thodum ◽  
Vineet K. Sharma
Keyword(s):  
Artificial Intelligence ◽  
Human Skin ◽  
Skin Microbiome ◽  
Intelligence Approach ◽  
Artificial Intelligence Approach

scholarly journals Complete Genome Sequence of Malassezia restricta CBS 7877, an Opportunist Pathogen Involved in Dandruff and Seborrheic Dermatitis

2019 ◽  
Vol 8 (6) ◽  
Author(s):  
Stanislas C. Morand ◽  
Morgane Bertignac ◽  
Agnes Iltis ◽  
Iris C. R. M. Kolder ◽  
Walter Pirovano ◽  
...  
Keyword(s):  
Human Skin ◽  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Seborrheic Dermatitis ◽  
Skin Microbiome ◽  
Basidiomycetous Yeasts ◽  
Content Type ◽  
Opportunist Pathogen ◽  
Malassezia Restricta

Malassezia restricta, one of the predominant basidiomycetous yeasts present on human skin, is involved in scalp disorders. Here, we report the complete genome sequence of the lipophilic Malassezia restricta CBS 7877 strain, which will facilitate the study of the mechanisms underlying its commensal and pathogenic roles within the skin microbiome.

Secretory Proteases of the Human Skin Microbiome

2021 ◽  
Author(s):  
Wisely Chua ◽  
Si En Poh ◽  
Hao Li
Keyword(s):  
Human Skin ◽  
Hydrolytic Enzymes ◽  
Microbial Interactions ◽  
Skin Microbiome ◽  
Protein Cleavage ◽  
Wide Range ◽  
Range Of Functions ◽  
Diverse Community ◽  
Secreted Proteases ◽  
Pathogenic Agents

The human skin is our outermost layer and serves as a protective barrier against external insults. Advances in next generation sequencing have enabled the discoveries of a rich and diverse community of microbes - bacteria, fungi and viruses that are residents of this surface. The genomes of these microbes also revealed the presence of many secretory enzymes. In particular, proteases which are hydrolytic enzymes capable of protein cleavage and degradation are of special interest in the skin environment which is enriched in proteins and lipids. In this minireview, we will focus on the roles of these skin-relevant microbial secreted proteases, both in terms of their widely studied roles as pathogenic agents in tissue invasion and host immune inactivation, and their recently discovered roles in inter-microbial interactions and modulation of virulence factors. From these studies, it has become apparent that while microbial proteases are capable of a wide range of functions, their expression is tightly regulated and highly responsive to the environments the microbes are in. With the introduction of new biochemical and bioinformatics tools to study protease functions, it will be important to understand the roles played by skin microbial secretory proteases in cutaneous health, especially the less studied commensal microbes with an emphasis on contextual relevance.

scholarly journals Is Financial Analysis Doomed? The Birth of “Reactive Valuation” Analysis

2017 ◽  
Vol 6 (3) ◽  
pp. 39
Author(s):  
Paul A. Griffin ◽  
Mohammedi Padaria
Keyword(s):  
Language Processing ◽  
Financial Analysis ◽  
Detailed Knowledge ◽  
Information Costs ◽  
Short Term ◽  
Traditional Concept ◽  
Statistical Arbitrage ◽  
Media Channels ◽  
Short Time ◽  
Information Landscape

The purpose of this paper is to examine how firms’ information landscape has changed in recent years and why this could be problematic for those engaged in financial analysis and equity valuation. Our central contention is that two main forces of change – lower information costs and faster information processing – have completely disrupted the traditional concept of financial analysis. In response to this disruption, financial analysis will now increasingly take the form of “reactive valuation.” In addition to examining our main contention, we introduce a new term into the literature, called “reactive valuation,” which we define as the ultra short-term valuation of an equity, lasting from a few seconds to a few hours, based on information primarily published through social media channels. It may be later corroborated by factually based information or remain unsubstantiated. It may or may not be from an authoritative source. It also may not relate clearly or directly to the valuation of the underlying asset. However, based mostly on the tools of artificial intelligence and natural language processing, “reactive valuation” will invariably provide an opportunity for statistical arbitrage during the short time it takes for the market to digest the information. Financial analysts who survive these two forces of change will have detailed knowledge of this new form of financial analysis.

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