Infections / 28.10.2024

MedicalResearch.com Interview with: Dr. Asaf Levy Senior Lecturer, Assistant Professor Plant Pathology and Microbiology The Robert H Smith Faculty of Agriculture, Food and Environment Hebrew University of Jerusalem MedicalResearch.com: What is the background for this study? Response: Bacteria encode many compounds used to target neighboring microbes or cause disease in hosts, including humans. Classic antibiotics (small molecules) are one well-studied group of antimicrobials encoded by bacteria. A less-studied group consists of short protein toxins. These proteins are produced by bacteria and injected into target cells to kill them. In this study, we focused on a group of protein toxins called polymorphic toxins, which carry a short toxin domain at their end, which we termed “PTs” (an acronym for polymorphic toxins) and are roughly 100 amino acid long. We developed a new algorithm to scan 107,000 bacterial genomes and discover novel PTs encoded by these bacteria. We then experimentally confirmed 9 new PT families that can kill bacteria and pathogenic fungi, including human pathogens, such as Candida auris and Aspergillus fumigatus. We saw that two of the toxins kill cells by degrading their DNA. (more…)
Author Interviews, Urinary Tract Infections / 21.03.2019

MedicalResearch.com Interview with: Prof. Lindsay E Nicolle Department of Internal Medicine, School of Medicine Rady Faculty of Health Sciences University of Manitoba, Winnipeg, Canada  MedicalResearch.com: What is the background for these updated guidelines? What are the main recommendations? Response: The guideline updates the guideline previously published in 2005. There is some new information published in the interim, but the recommendations from the earlier guideline have not changed. In addition, some populations not included in the 2005 guideline are addressed in the update. These include children, transplant recipients, and patients undergoing elective surgery with prosthesis implantation. (more…)
Author Interviews, Infections, MRSA, NIH, Probiotics / 12.10.2018

MedicalResearch.com Interview with: "staph aureus on blood agar" by Iqbal Osman is licensed under CC BY 2.0Pipat Piewngam Postdoctorol fellow Pathogen Molecular Genetics Section, Laboratory of Bacteriology, NIAID/NIH Bethesda, MD, USA 20892  MedicalResearch.com: What is the background for this study? What are the main findings?  Response: Our team at National Institutes of health, Mahidol University and Rajamangala University of Technology in Thailand has reported that the consumption of probiotic Bacillus bacteria comprehensively abolishes colonization with the dangerous pathogen, Staphylococcus aureus. We hypothesized that the composition of the human gut microbiota affects intestinal colonization with S. aureus. We collected fecal samples from 200 healthy individuals from rural populations in Thailand and analyzed the composition of the gut microbiome by 16S rRNA sequencing. Surprisingly, we did not detect significant differences in the composition of the microbiome between S. aureus carriers and non-carriers. We then sampled the same 200 people for S. aureus in the gut (25 positive) and nose (26 positive). Strikingly, we found no S. aureus in any of the samples where Bacillus were present. In mouse studies, we discovered S. aureus Agr quorum-sensing signaling system that must function for the bacteria to grow in the gut. Intriguingly, all of the more than 100 Bacillus isolates we had recovered from the human feces efficiently inhibited that system. Then, we discovered that the fengycin class of Bacillus lipopeptides achieves colonization resistance by inhibiting that system. To further validate their findings, we colonized the gut of mice with S. aureus and fed them B. subtilis spores to mimic probiotic intake. Probiotic Bacillus given every two days eliminated S. aureus in the guts of the mice. The same test using Bacillus where fengycin production had been removed had no effect, and S. aureus grew as expected. This is one of the first study that provide human evidence supporting the biological significance of probiotic bacterial interference and show that such interference can be achieved by blocking a pathogen’s signaling system. (more…)
Author Interviews, Exercise - Fitness, Microbiome, UCSF / 12.07.2018

MedicalResearch.com Interview with: James R. Bagley, PhD Assistant Professor of Kinesiology Director, Muscle Physiology Lab Co-Director, Exercise Physiology Lab Research Director, Strength & Conditioning Lab San Francisco State University MedicalResearch.com: What is the background for this study? What are the main findings? Response: The human body contains many billions of bacteria cells, and the type of bacteria in your gastrointestinal tract (termed gut microbiota) has been linked to certain diseases. Most of your gut microbiota falls into two categories: Firmicutes (F) or Bacteroidetes (B). The relative gut F/B ratio has been used to assess microbiota health. Our study was the first to examine potential relationships among F/B ratio and cardiorespiratory fitness, body composition, and diet in healthy young men and women We recruited 37 healthy adults to undergo a battery of physiological tests and collected stool samples to analyze their gut F/B ratio using qPCR. We found that F/B ratio was significantly correlated with cardiorespiratory fitness, but with no other variables. In fact, this correlation was so strong that a person’s fitness level explained ~22% of the variance in their gut bacteria composition. (more…)
Author Interviews, Hospital Acquired, Infections / 22.06.2018

MedicalResearch.com Interview with: Richard Stanton, PhD Health Scientist, Division of Healthcare Quality Promotion Centers for Disease Control and Prevention MedicalResearch.com: What is the background for this study? Response: We used whole genome sequencing (WGS) to investigate an outbreak of carbapenem-resistant Enterobacteriaceae (CRE) that occurred in an acute care hospital in Kentucky over a six month period in late 2016. The outbreak included 18 cases of CRE. (more…)
Author Interviews, Baylor College of Medicine Houston, C. difficile, Nature / 05.01.2018

MedicalResearch.com Interview with: Professor Robert Britton PhD Therapeutic Microbiology Laboratory Department of Molecular Virology and Microbiology Alkek Center for Metagenomics and Microbiome Research Baylor College of Medicine MedicalResearch.com Interview: How would you summarise your findings? Response: As a brief summary of our work, certain strains of Clostridium difficile have emerged in the past 20 years that have resulted in epidemics worldwide, leading to C. difficile becoming one of the most common causes of hospital acquired infections.  Two ribotypes of C. difficile, RT027 and RT078, emerged as key epidemic ribotypes associated with increased disease prevalence and increased mortality in patients.  We found that both of these ribotypes have acquired the ability to consume the disaccharide trehalose by two completely independent mechanisms.  We further show that trehalose enhances disease severity of C. difficile infection in a manner that requires C. difficile to metabolize trehalose in mice.  We also show that trehalose is present in the distal intestine of mice and humans in concentrations that the RT027 ribotype can metabolize.  Because RT027 and RT078 strains were present in clinics at least 10-20 years prior to their becoming epidemic isolates, we looked where people would acquire trehalose in the diet. In 2000 the FDA approved trehalose for human consumption (EFSA did so in 2001) and based on the GRAS report from the FDA the amount of trehalose predicted to be consumed once released on the market would vastly increase what people get naturally from the diet.  Our data support that these two ribotypes increased in prevalence due to a change in the human diet. (more…)
Author Interviews, Dermatology, Infections, Johns Hopkins / 09.11.2017

MedicalResearch.com Interview with: Lloyd S. Miller, M.D., Ph.D. Vice Chair for Research, Department of Dermatology Associate Professor of Dermatology, Infectious Diseases, Orthopaedic Surgery & Materials Science and Engineering Faculty Member, Cellular and Molecular Medicine (CMM) and Pathobiology Graduate Programs Johns Hopkins Department of Dermatology Baltimore, MD 21231  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Staphylococcus aureus is a common bacterial skin pathogen and its abundance is greatly increased on affected skin of eczema patients, especially during disease flares. However, how S. aureus induces skin inflammation and exacerbates the skin inflammation is incompletely understood. In this study, we found that S. aureus exposure of mouse skin induced skin inflammation through an inflammatory mediator known as IL-36. (more…)
Author Interviews, Gastrointestinal Disease, Infections, Microbiome, Rheumatology, Science / 11.02.2017

MedicalResearch.com Interview with: Randy Longman, M.D. / Ph.D. Assistant Professor of Medicine Jill Roberts Center and Institute for Research in Inflammatory Bowel Disease Weill Cornell Medicine Division of Gastroenterology and Hepatology Joan and Sanford I. Weill Department of Medicine Department of Microbiology and Immunology New York, NY 10021  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Inflammatory bowel disease is not limited to intestinal inflammation.  Up to 1/3 of patients with active disease suffer from extra-intestinal manifestations. The most common extra-intestinal manifestations in IBD is joint inflammation or spondyloarthritis.  Peripheral joint spondyloarthritis  carries a prevalence of 20% in Crohn’s Disease and 10% in Ulcerative Colitis, predominantly affecting joints of the lower limbs.  It has long been suggested that gut bacteria can drive this systemic joint inflammation, but microbial targets have not been characterized. (more…)
Author Interviews, Infections / 28.09.2016

MedicalResearch.com Interview with: Dr. Bashir A. Lwaleed PhD, FRCPath, PGCAP, FHEA, CBiol FSB, FIBMS Faculty of Health Sciences University of Southampton South Academic and Pathology Block (MP 11) Southampton General Hospital Southampton UK MedicalResearch.com: What is the background for this study? Response: The study merges two longstanding interests. We have long worked out of several departments at Southampton and Portsmouth on the therapeutic potential for natural products (including the medium – chain fatty acids GLA (evening primrose oil) and EPA (fish oil) as well as honeys from a number of floral sources. Secondly, there is an established research theme in the Faculty of Healthcare Science at Southampton addressing continence related issues; moreover catheter management as an economic and infection control issue is a major concern in the NHS Trust Urology department. Biofilms on catheters are sources of infection, honey has proven antibacterial (and other therapeutic) properties in topical applications such as skin ulceration. It is a logical step to assess whether a similar use may be made for honey instilled into the bladder and/or flushing the lumen of a catheter. (more…)
Author Interviews, Dental Research, Esophageal, Infections / 02.03.2016

MedicalResearch.com Interview with: Dr. Huizhi Wang Assistant Professor Department of Oral Immunology and Infectious Diseases University of Louisville School of Dentistry Louisville, KY  MedicalResearch.com: What is the background for this study? What are the main findings? Dr. Wang: Esophageal cancer is the eighth most frequent tumor and sixth leading cause of cancer death worldwide, characterized by rapid development and poor prognosis, including high mortality. Whereas the majority of cases occur in Asia, particularly in central China, recent data suggest that the frequency of new cases is rising in Western Europe and the USA. Mounting evidence suggests a causal relationship between specific bacterial infections and the development of certain malignancies. However, the possible role of the keystone periodontal pathogen, Porphyromonas gingivalis, in esophageal squamous cell carcinoma (ESCC) was unknown before our study. We found P. gingivalis infects epithelium of cancerous tissues up to 61%, as compared with 12% of adjacent tissues and non-infected in normal esophageal mucosa. A similar distribution of lysine-specific gingipain, a catalytic endoprotease uniquely secreted by P. gingivalis, and P. gingivalis DNA was observed. Moreover, we found infection of P. gingivalis was positively associated with the multiple clinicopathologic characteristics, including differentiation status, metastasis, and overall survival rate.  (more…)
Author Interviews, Dermatology, Infections, JAMA / 15.03.2015

MedicalResearch.com Interview with: Dr. Ana Ramírez-Boscá, MD Department of Dermatology and Clinical Research UnitDr. Ana Ramírez-Boscá, MD Department of Dermatology and Clinical Research Unit and Vicente Navarro-López, MD Clinical Research Unit and Infectious Diseases Unit Centro Dermatológico Estético, Alicante, SpainVicente Navarro-López, MD Clinical Research Unit and Infectious Diseases Unit Centro Dermatológico Estético, Alicante, Spain   MedicalResearch: What is the background for this study? What are the main findings? Response: Infections have been related with the pathogenesis of guttate psoriasis, however antibiotic treatment does not improve prognosis nor does it affect the evolution of the disease. The association between psoriasis and other infectious diseases has been reported as well, although in these cases there is scarce information on the causative microbial likely involved and the role of these bacteria in the pathogenesis of this skin disease. MedicalResearch: What are the main findings?  Response: Bacterial DNA may be detected in bloodstream of a significant proportion of patients with active plaque psoriasis. Increased levels of pro-inflammatory cytokines in patients with presence of bacterial DNA but not in patients without presence of bacterial genomic fragments suggest a role of bacterial DNA translocation in inducing an inflammatory response. (more…)
Author Interviews, Infections / 02.12.2014

Jack A Gilbert PhD Department of Ecology & Evolution Graduate Program in Biophysical Sciences University of Chicago, Chicago, IL 60637,MedicalResearch.com Interview with: Jack A Gilbert PhD Department of Ecology & Evolution Graduate Program in Biophysical Sciences University of Chicago, Chicago, IL 60637 MedicalResearch: What is the background for this study? What are the main findings? Dr. Gilbert: We have performed extensive analysis of the microbial distribution between humans and home surfaces in peoples houses. And are still exploring how bacteria are distributed around hospitals. Here we wanted to explore how bacteria from humans were distributed into a space in real time. By taking samples every hour post sterilization and seeing how the community stabilized, who remained active and whether they were pathogenic. We found that communities stabilized on a skin-associated microbiome within 5 hours, that staphylococcus remained active and yet none of these were particularly pathogenic. Yet we were able to identify pathogenic MRSA on surfaces around the bathroom, but they were extremely rare. (more…)
Author Interviews, Cleveland Clinic, Heart Disease, JACC / 29.10.2014

Professor of Medicine, Cleveland Clinic Lerner College of Medicine at CWRU Director, Cardiomyopathy Program, Kaufman Center for Heart Failure Research Director, Section of Heart Failure and Cardiac Transplantation Medicine Heart and Vascular Institute, Cleveland Clinic Cleveland, OH 44195MedicalResearch.com Interview with: W. H. Wilson Tang, MD FACC FAHA Professor of Medicine, Cleveland Clinic Lerner College of Medicine at CWRU Director, Cardiomyopathy Program, Kaufman Center for Heart Failure Research Director, Section of Heart Failure and Cardiac Transplantation Medicine Heart and Vascular Institute, Cleveland Clinic Cleveland, OH 44195 Medical Research: What are the main findings of the study? Dr. Tang: A chemical byproduct of gut bacteria-dependent digestion, TMAO (trimethylamine N-oxide), was previously shown to contribute to heart disease development. In this study, blood levels of TMAO for the first time are linked to heart failure development and mortality risk. (more…)
Author Interviews, Dental Research / 29.08.2014

Donna Warren Morris, RDH, Med Professor, Dean's Academy of Distinguished Teaching Scholars Houston, TX 77054 MedicalResearch.com Interview with:  Donna Warren Morris, RDH, Med Professor, Dean's Academy of Distinguished Teaching Scholars Houston, TX 77054 Medical Research: What are the main findings of the study? Answer: Power toothbrushes can harbor microorganisms that have been shown to cause disease and infections. A solid-head design was found to have less growth of microorganisms than two others with hollow head designs. (more…)
Author Interviews, Gastrointestinal Disease, mBio / 04.08.2014

Dr. Sridhar Mani MD Departments of Genetics and Medicine Albert Einstein College of Medicine, Bronx, NY 10461MedicalResearch.com Interview with: Dr. Sridhar Mani MD Departments of Genetics and Medicine Albert Einstein College of Medicine Bronx, NY 10461

  Medical Research: What are the main findings of the study? Dr. Mani: In a series of studies using cells grown in the lab and mouse studies, the researchers found that a metabolite called indole 3-propionic acid (IPA)—produced exclusively by so-called commensal bacteria —both strengthens the intestinal epithelium’s barrier function and prevents its inflammation by activating an orphan nuclear receptor, Pregnane X Receptor (PXR). Specifically, PXR activation suppresses production of an inflammatory protein called tumor necrosis factor alpha (TNF-á) while increasing levels of a protein that strengthens the junctions between intestinal epithelial cells (makes the intestines less permeable to noxious substances). Loss of PXR protein and/or IPA results in a disrupted intestinal barrier and increased propensity towards intestinal inflammation and/or toxin induced injury to the intestines. (more…)
Author Interviews, Infections / 28.12.2013

Anders P. Hakansson, Ph.D. Assistant Professor of Microbiology Department of Microbiology and Immunology Buffalo, NY 14214MedicalResearch.com Interview with: Anders P. Hakansson, Ph.D. Assistant Professor of Microbiology Department of Microbiology and Immunology Buffalo, NY 14214 MedicalResearch.com: What are the main findings of the study: Dr. Hakansson: During the last couple of years we have shown that Streptococcus pneumoniae, a common colonizer of the nasopharynx in small children and elderly that sometimes cause respiratory infections such as middle ear infections and pneumonia, and Streptococcus pyogenes, a common colonizer of the oropharynx and also the cause of strep throat and skin infections, colonize us humans by forming biofilms; intricate bacterial communities. Biofilms have been studied for a long time but these specific organisms have not been shown to form biofilms during colonization until recently. As biofilms are much more resistant to environmental stresses and antibiotics, we were interested to see whether biofilms formed by these organisms could survive in the environment. The main reason for doing the experiments was that CDC guidelines indicate that spread of these organisms between individuals occur solely by inhalation of bacteria-containing droplets after coughing or sneezing. The risk of spread through surfaces has been estimated to be very low as laboratory experiments over the last 40 years have shown that these bacteria die very rapidly on surfaces. These studies were not, however, done with biofilm bacteria. Laura Marks in the laboratory with help from Ryan Reddinger therefore first tested how long biofilm bacteria could survive on plastic surfaces and found that rather than hours these bacteria were alive even after a month and could be used to successfully colonize animals. This made us interested in understanding if these bacteria survive better on hands, a common way to spread bacteria. And just as on inanimate surfaces, the biofilms survived much better on hands than bacteria grown in laboratory media. Based on these results, we were allowed to sample bacteria from stuffed toys, books, crib linens and others surfaces in a day care center early in the morning before the children arrived, and found both S. pneumoniae and S. pyogenes on these items. The results of the study indicate that these bacteria can survive in the environment longer than we have previously thought and may therefore play a role in spread between individuals. (more…)