scholarly journals The spatial heterogeneity of the gut limits bacteriophage predation leading to the coexistence of antagonist populations of bacteria and their viruses

2019 ◽  
Author(s):  
Marta Lourenço ◽  
Lorenzo Chaffringeon ◽  
Quentin Lamy-Besnier ◽  
Pascal Campagne ◽  
Claudia Eberl ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Phage Therapy ◽  
Arms Race ◽  
Enteric Pathogens ◽  
Human Gut ◽  
Heterogeneous Distribution ◽  
Spatial Refuge ◽  
Low Efficiency ◽  
Over Time

AbstractBacteria and their viruses, bacteriophages (phages), are the most abundant components of the mammalian gut microbiota where these two entities coexist over time. The ecological dynamics underlying the coexistence between these two antagonistic populations in the gut are unknown. We challenged a murine synthetic bacterial community with a set of virulent phages, to study the factors allowing phages-bacteria coexistence in the gut. We found that coexistence was neither dependent on an arms race between bacteria and phages, nor on the ability of phages to extend host range. Instead, our data suggest that some phage-inaccessible sites in the mucosa of the ileum serve as a spatial refuge for bacteria, which from there disseminate in the gut lumen. Luminal phages amplify by infecting luminal bacteria maintaining phage throughout the gut. We conclude that the heterogeneous distribution of microbes in the gut contributes to the long-term coexistence of phages with phage-susceptible bacteria. This observation could explain the persistence in the human gut of intestinal phages, such as the crAssphage, as well as the low efficiency of oral phage therapy against enteric pathogens in animal models and clinical trials.

scholarly journals Phage Therapy with a focus on the Human Microbiota

Antibiotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 131 ◽  
Author(s):  
Ganeshan ◽  
Hosseinidoust
Keyword(s):  
Infectious Disease ◽  
Antibacterial Activity ◽  
Antibiotic Resistance ◽  
Therapeutic Agent ◽  
Phage Therapy ◽  
Arms Race ◽  
Phage Resistance ◽  
Bacteriophage Therapy ◽  
Human Gut ◽  
Human Microbiota

Bacteriophages are viruses that infect bacteria. After their discovery in the early 1900s, bacteriophages were a primary cure against infectious disease for almost 25 years, before being completely overshadowed by antibiotics. With the rise of antibiotic resistance, bacteriophages are being explored again for their antibacterial activity. One of the critical apprehensions regarding bacteriophage therapy, however, is the possibility of genome evolution, development of phage resistance, and subsequent perturbations to our microbiota. Through this review, we set out to explore the principles supporting the use of bacteriophages as a therapeutic agent, discuss the human gut microbiome in relation to the utilization of phage therapy, and the co-evolutionary arms race between host bacteria and phage in the context of the human microbiota.

scholarly journals The Unique Impact of COVID-19 on Human Gut Microbiome Research

2021 ◽  
Vol 8 ◽  
Author(s):  
Ella Burchill ◽  
Eva Lymberopoulos ◽  
Elisa Menozzi ◽  
Sanjay Budhdeo ◽  
James R. McIlroy ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Gut Microbiome ◽  
Indirect Effects ◽  
Population Level ◽  
Faecal Microbiota ◽  
Human Gut ◽  
Human Gut Microbiome ◽  
Microbiome Research ◽  
Potential Impact

The coronavirus (COVID-19) pandemic has disrupted clinical trials globally, with unique implications for research into the human gut microbiome. In this mini-review, we explore the direct and indirect influences of the pandemic on the gut microbiome and how these can affect research and clinical trials. We explore the direct bidirectional relationships between the COVID-19 virus and the gut and lung microbiomes. We then consider the significant indirect effects of the pandemic, such as repeated lockdowns, increased hand hygiene, and changes to mood and diet, that could all lead to longstanding changes to the gut microbiome at an individual and a population level. Together, these changes may affect long term microbiome research, both in observational as well as in population studies, requiring urgent attention. Finally, we explore the unique implications for clinical trials using faecal microbiota transplants (FMT), which are increasingly investigated as potential treatments for a range of diseases. The pandemic introduces new barriers to participation in trials, while the direct and indirect effects laid out above can present a confounding factor. This affects recruitment and sample size, as well as study design and statistical analyses. Therefore, the potential impact of the pandemic on gut microbiome research is significant and needs to be specifically addressed by the research community and funders.

Treatment and secondary prevention of venous thromboembolism in cancer patients

2012 ◽  
Vol 03 (03) ◽  
pp. 121-125
Author(s):  
I. Pabinger ◽  
C. Ay
Keyword(s):  
Clinical Trials ◽  
Venous Thromboembolism ◽  
Cancer Patients ◽  
Oral Anticoagulants ◽  
Factor Xa ◽  
New Oral Anticoagulants ◽  
Phase Iii ◽  
Patients With Cancer ◽  
Potential Use

SummaryCancer is a major and independent risk factor of venous thromboembolism (VTE). In clinical practice, a high number of VTE events occurs in patients with cancer, and treatment of cancerassociated VTE differs in several aspects from treatment of VTE in the general population. However, treatment in cancer patients remains a major challenge, as the risk of recurrence of VTE as well as the risk of major bleeding during anticoagulation is substantially higher in patients with cancer than in those without cancer. In several clinical trials, different anticoagulants and regimens have been investigated for treatment of acute VTE and secondary prophylaxis in cancer patients to prevent recurrence. Based on the results of these trials, anticoagulant therapy with low-molecular-weight heparins (LMWH) has become the treatment of choice in cancer patients with acute VTE in the initial period and for extended and long-term anticoagulation for 3-6 months. New oral anticoagulants directly inhibiting thrombin or factor Xa, have been developed in the past decade and studied in large phase III clinical trials. Results from currently completed trials are promising and indicate their potential use for treatment of VTE. However, the role of the new oral thrombin and factor Xa inhibitors for VTE treatment in cancer patients still has to be clarified in further studies specifically focusing on cancer-associated VTE. This brief review will summarize the current strategies of initial and long-term VTE treatment in patients with cancer and discuss the potential use of the new oral anticoagulants.

Enhancing community welfare through improved water quality: a case for applying staggered pollution charges in the river Musi sub-basin of Andhra Pradesh, India

Water Policy ◽  
2005 ◽  
Vol 7 (5) ◽  
pp. 469-483
Author(s):  
Tishya Chatterjee
Keyword(s):  
Andhra Pradesh ◽  
Relevant Literature ◽  
Pollution Prevention ◽  
Economic Benefits ◽  
Environmental Damage ◽  
Marginal Costs ◽  
Community Acceptance ◽  
Level Data ◽  
Over Time

In conditions of severe water-pollution and dormant community acceptance of accumulating environmental damage, the regulator's role goes beyond pollution prevention and more towards remediation and solutions based on the community's long-term expectations of economic benefits from clean water. This paper suggests a method to enable these benefits to become perceptible progressively, through participatory clean-up operations, supported by staggered pollution charges. It analyses the relevant literature on pollution prevention and applies a cost-based “willingness to pay” model, using primary basin-level data of total marginal costs. It develops a replicable demand-side approach imposing charge-standard targets over time in urban-industrial basins of developing countries.

The Effect of Probiotics Supplementation in Maternal-Fetal Care

2020 ◽  
Vol 16 ◽  
Author(s):  
Mahnaz Mardani ◽  
Sadegh Rezapour
Keyword(s):  
Diabetes Mellitus ◽  
Protective Role ◽  
Optimum Dose ◽  
Active Living ◽  
Maternal Weight Gain ◽  
Long Term Effects ◽  
Maternal Weight ◽  
Human Gut ◽  
Obesity And Diabetes

: Pregnancy-related complications can have long-term effects on mother and fetus/child. Microbiome within the human gut is an important factor to maintain optimum health during pregnancy and could possibly reduce the incidence of these complications. Probiotics are active living microorganisms that can provide the host with health benefits such as; immune and hormonal regulatory and metabolic benefits when administered in adequate and optimum dose. Probiotic supplementations also regulate abnormal and unbalanced microflora population that can control the pathogenesis of several diseases like obesity and diabetes. Probiotics also play a protective role in complications like preeclampsia, gestational diabetes mellitus and maternal weight gain and enhance successful outcomes of reproduction. This mini review will thereby summarize the maternal and fetal effects of probiotics during pregnancy.

The Short-Term and Long-Term Impacts of Sarbanes-Oxley Act on Composition and Characteristics of Corporate Board of Directors

2015 ◽  
Vol 5 (4) ◽  
Author(s):  
Halil Kaya ◽  
Gaurango Banerjee
Keyword(s):  
Board Composition ◽  
Corporate Boards ◽  
Corporate Accountability ◽  
Corporate Board ◽  
Short Term ◽  
Dual Roles ◽  
Board Characteristics ◽  
Sarbanes Oxley ◽  
Over Time

The paper examines the Sarbanes-Oxley (2002) Acts immediate impact on board composition and characteristics as well as possible reversals in its impact over time. Effects on directors age and tenure are analyzed over the 2001-06 sample period. Female participation in corporate boards is also studied in the pre-SOX and post-SOX periods. The dual roles of directors in being a member of the board as well as serving as either CEO, CFO, Chairman, Co-Chair, Founder, or Lead Director of their respective companies is also examined. We observe a short-term impact of SOX on board compositions due to changes seen in board characteristics between 2001 (pre-SOX), and 2003-05 short-term period (post-SOX). Also, we observe a reversal of board characteristics in 2006 to pre-SOX levels implying that the effects of SOX on board composition were short-lived, and needs to be monitored over time to ensure adherence to corporate accountability guidelines over the long-term.

A Downward Spiral? A Panel Study of Misinformation and Media Trust in Chile

2021 ◽  
pp. 194016122110252
Author(s):  
Sebastián Valenzuela ◽  
Daniel Halpern ◽  
Felipe Araneda
Keyword(s):  
News Media ◽  
Panel Study ◽  
Future Research ◽  
Panel Survey ◽  
Downward Spiral ◽  
The Media ◽  
Media Trust ◽  
People’S Attitudes ◽  
Over Time

Despite widespread concern, research on the consequences of misinformation on people's attitudes is surprisingly scant. To fill in this gap, the current study examines the long-term relationship between misinformation and trust in the news media. Based on the reinforcing spirals model, we analyzed data from a three-wave panel survey collected in Chile between 2017 and 2019. We found a weak, over-time relationship between misinformation and media skepticism. Specifically, initial beliefs on factually dubious information were negatively correlated with subsequent levels of trust in the news media. Lower trust in the media, in turn, was related over time to higher levels of misinformation. However, we found no evidence of a reverse, parallel process where media trust shielded users against misinformation, further reinforcing trust in the news media. The lack of evidence of a downward spiral suggests that the corrosive effects of misinformation on attitudes toward the news media are less serious than originally suggested. We close with a discussion of directions for future research.

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