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Gregor Reid

Publications and source records attributed to Gregor Reid.

At least 37 records · Page 2Linked to original sources

Selected topics in probiotics and prebiotics: meeting report for the 2004 international scientific association for probiotics and prebiotics.

On August 29-31, 2004, 84 academic and industry scientists from 16 countries gathered in Copper Mountain, Colorado USA to discuss certain issues at the forefront of the science of probiotics and prebiotics. The format for this invitation only meeting included six featured lectures: engineering human vaginal lactobacilli to express HIV-inhibitory molecules (Peter Lee, Stanford University), programming the gut for health (Thaddeus Stappenbeck, Washington University School of Medicine), immune modulation by intestinal helminthes (Joel Weinstock, University of Iowa Hospitals and Clinics), hygiene as a cause of autoimmune disorders (G. A. Rook, University College London), prebiotics and bone health (Connie Weaver, Purdue University) and prebiotics and colorectal cancer risk (Ian Rowland, Northern Ireland Centre for Food and Health). In addition, all participants were included in one of eight discussion groups on the topics of engineered probiotics, host-commensal bacteria communication, 'omics' technologies, hygiene and immune regulation, biomarkers for healthy people, prebiotic and probiotic applications to companion animals, development of a probiotic dossier, and physiological relevance of prebiotic activity. Brief conclusions from these discussion groups are summarized in this paper.

Animals↗

Taking probiotics during pregnancy. Are they useful therapy for mothers and newborns?

QUESTION: Recently, several of my pregnant patients have asked me about using probiotics during pregnancy. Is there any evidence that these innocuous bacteria work effectively? ANSWER: An increasing body of evidence suggests that probiotics are effective for treating bacterial vaginosis and allergic reactions. Most probiotics available in Canada, however, are of dubious quality, and, for many claimed indications, there is no proof of effectiveness yet.

Dermatitis, Atopic↗

Probiotics. Some evidence of their effectiveness.

OBJECTIVE: To define the term probiotics, to indicate how to identify products that have been proven beneficial, and to assess the quality of evidence regarding probiotics. QUALITY OF EVIDENCE: A few level I studies support the effectiveness of specific probiotics for certain diagnoses. For most so-called probiotics, however, weak or no evidence supports their effectiveness. MAIN MESSAGE: Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Level I evidence supports use of VSL#3 for maintaining remission of inflammatory colitis. Probiotics for treating vaginal infections, Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14, have level I evidence of effectiveness, but are not available in Canada. Specific probiotics taken for certain indications improve health and have few side effects. CONCLUSION: Limited but good evidence supports the role of certain probiotics in medical practice. Because consumer pressure will undoubtedly stimulate further interest in probiotics, family doctors need to be informed about them so they can advise their patients appropriately.

Canada↗

Novel insight into the vaginal microflora in postmenopausal women under hormone replacement therapy as analyzed by PCR-denaturing gradient gel electrophoresis.

OBJECTIVES: A study was conducted to use new molecular technologies to identify the vaginal bacterial species of postmenopausal women under oral estrogen therapy (Premarin-conjugated equine estrogen, CEE). STUDY DESIGN: Nineteen postmenopausal women under CEE treatment were recruited and their vaginal flora were analyzed during 3 months, using polymerase chain reaction in combination with denaturing gradient gel electrophoresis (DGGE) and sequencing of DNA fragments. RESULTS: Sixty-eight percent of the women presented with a 'Normal' Nugent score at the first sampling time (d0). All the subjects had bacterial species detected in their vaginal flora. Lactobacillus species were detected in all samples. Moreover, 53% of the women had lactobacilli exclusively at d0. Two Lactobacillus species were dominant, and were recovered from the majority of samples (L. iners and L. crispatus). Forty-four percent of the samples also contained other bacterial species, which were potential urogenital pathogens. Candida albicans was detected in 26% of the subjects. The vaginal flora of the women under CEE treatment were different from that of postmenopausal women not receiving hormone therapy, but very similar to premenopausal women. CONCLUSIONS: The present study indicates that one benefit from hormone replacement therapy (HRT) is the restoration of a lactobacilli vaginal flora associated with a protective effect against urogenital infections.

Adult↗

When microbe meets human.

Microbes make up a significant component of the human body, yet relatively little is known about how they influence health and disease. They colonize after birth by chance and circumstance, yet play a major role in immunity, digestion, and protection against disease. In relatively recent times, basic science and clinical studies have clearly shown the potential impact of indigenous and exogenous microbes on human health and well-being. Yet regulatory bodies, research funding agencies, and health care practitioners, perhaps disillusioned by too many unreliable, overhyped products that are marketed under the guise of probiotics or natural therapeutics, have lagged far behind in embracing this avenue of enquiry. As more scientifically proven probiotic products differentiate themselves from untested and unproven cure-alls, and as multidisciplinary research groups piece together the diverse components of the puzzle, humans will slowly begin to understand how best to optimize their coexistence with microbial organisms, thus perhaps prolonging and enhancing life.

Animals↗

The rationale for probiotics in female urogenital healthcare.

Urogenital infections are a major reason that women visit their family physician and are referred to gastroenterology, gynecology, urology, and infectious disease specialists. The association between abnormal vaginal microbiota and increased risk for sexually transmitted infections, bladder and vaginal infections per se, and a higher rate of preterm labor indicate the need to better understand and manage urogenital health. The concept of probiotics arose from the realization that humans are inhabited with microbes from birth and that these organisms play a role in preventing disease. Defined as "live microorganisms, which when administered in adequate amounts confer a health benefit on the host," probiotic strains have already been shown to effectively prevent diarrhea and to hold potential in preventing and treating tonsillitis, caries, renal calculi, and respiratory infections. This review provides a rationale for the use of probiotics in maintaining female vaginal and bladder health and as a treatment option for recurrent bacterial vaginosis, urinary tract infection, yeast vaginitis, and sexually transmitted infections. We consider only probiotic strains that fulfill the United Nations/World Health Organization Guidelines for Probiotics in being fully characterized and clinically documented through scientific investigations describing known or presumed mechanisms of action. Although medical practitioners as yet are unable to access these probiotic strains, an awareness of recent and ongoing research for probiotics is important, as results are encouraging. The concept of probiotic therapy is familiar to many consumers and although it has historically lacked credibility in the medical community, perceptions are changing.

Bacterial Infections↗

Surface-enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS): a new proteomic urinary test for patients with urolithiasis.

SELDI-TOF-MS is a highly sensitive protein-analysis tool capable of detecting minute protein profile differences between biological samples. As proteins have been associated with urinary tract calculi, protein-based urinalysis may offer insights into their diagnosis. The purpose of this study was to evaluate SELDI-TOF-MS as a potential method for identifying urinary biomarkers of urolithiasis. Midstream sterile urine samples were obtained from 25 male patients with a confirmed diagnosis of urolithiasis (test group) and 25 male subjects with no known history of the disease (controls). Urinary levels of oxalate, total protein, albumin, and osteopontin were determined. Protein profiles were generated using SELDI-TOF-MS.SELDI-TOF-MS profiling revealed a relationship between protein peak intensities at 67 and 24 kDa that differed between the two groups. The ratio of p67:p24 was found to be less than 1.0 in all of the control samples (mean 0.26), while 18 out of 25 (72%) of the test group samples displayed a ratio greater than 1.0 (total group mean 4.75, P<0.001). Albumin, total protein, and oxalate levels were higher in the test group than the controls. Although SELDI-TOF-MS is not yet in widespread use in hospital and diagnostic laboratories, this system represents a promising new method for rapidly identifying patients with urolithiasis.

Albumins↗

Nucleic acid-based diagnosis of bacterial vaginosis and improved management using probiotic lactobacilli.

Bacterial vaginosis (BV) is a common condition in women that represents an imbalance of the vaginal microflora, lactobacilli depletion, and excess growth of mainly anaerobic Gram-negative pathogens. Diagnosis is made using a series of tests or a Gram stain of a vaginal smear. Treatment with antibiotics is quite effective, but recurrences are common. A study of 55 vaginal samples from 11 postmenopausal women showed the presence of BV by the Gram stain-based Nugent scoring system, and polymerase chain reaction-denaturing gradient gel electrophoresis showed that Bacteroides or Prevotella species were the most common isolates recovered (24 of 25), with Escherichia coli, Staphylococcus aureus, and Streptococcus agalactiae also found in some samples. In one case, only Gardnerella vaginalis was found. These findings illustrate that BV remains common even among otherwise healthy women, but it is not caused solely by either Gardnerella or Mobiluncus. Use of a FemExam system (Cooper Surgical, Shelton, CT), based upon elevated pH and trimethylamine levels, to screen vaginal smears from 59 healthy women showed poor correlation with the Gram stain method. A randomized, placebo-controlled trial of these subjects showed that the lactobacilli-dominant microbiota was restored in subjects with BV but not in controls, following 2 months of daily oral intake of Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14. These studies show that nucleic acid-based methods are effective at identifying bacteria responsible for BV. If such methods could be used to develop a commercially available, self-use kit, women would be much better placed to take control of their own health, for example, using medicinal food or dietary supplement products such as the clinically proven probiotic strains L. rhamnosus GR-1 and L. fermentum RC-14.

Adult↗

Urinary tract biomaterials.

PURPOSE: As a result of endourological advances, biomaterials have become increasingly used within the urinary tract. This review article provides an update on the current status of urinary tract biomaterials, discussing issues of biocompatibility, biomaterials available for use, clinical applications and biomaterial related complications. Perspectives on future materials for use in the urinary tract are also provided. MATERIALS AND METHODS: We performed a comprehensive search of the peer reviewed literature on all aspects of biomaterials in the urinary tract using PubMed and MEDLINE. All pertinent articles were reviewed in detail. RESULTS: Any potential biomaterial must undergo rigorous physical and biocompatibility testing prior to its commercialization and use in humans. There are currently many different bulk materials and coatings available for the manufacturing of biomaterials, although the ideal material has yet to be discovered. For use in the urinary tract, biomaterials may be formed into devices, including ureteral and urethral stents, urethral catheters and percutaneous nephrostomy tubes. Despite significant advances in basic science research involving biocompatibility issues and biofilm formation, infection and encrustation remain associated with the use of biomaterials in the urinary tract and, therefore, limit their long-term indwelling time. CONCLUSIONS: Prosthetic devices formed from biomaterials will continue to be an essential tool in the practicing urologist's armamentarium. Ongoing research is essential to optimize biocompatibility and decrease biomaterial related complications such as infection and encrustation within the urinary tract. Future advances include biodegradables, novel coatings and tissue engineering.

Biocompatible Materials↗

Probiotics for mother and child.

For the survival of humankind, nothing can be as important as the health of a mother and a child. As the world's population grows to more than 6 billion, it might seem ridiculous to suggest that any real threat exists to the human species. Diseases have long ravaged populations, as have wars, poverty, and malnutrition. Life today is no different with new and emerging diseases such as SARS and Mad Cow Disease leaving a trail of concern around the planet. All that being said, the AIDS crisis is threatening humans like no other. In countries such as Botswana, close to half the population of pregnant women is infected. Of great concern, the disease is now prevalent among women and teenage girls, threatening not only their lives but those of their offspring. Efforts to control this spread are quite abysmal, albeit well intentioned. Likewise, the death of a child every 15 seconds from diarrheal disease is not being addressed with the same vigor as SARS, even though the risk of dying from the latter for most people is similar to being struck by lightning. In the end, it is the economy and politics that dictate health spending. Image and perception are everything. While deaths mount among women and children from AIDS and other infections, the potential to intervene with a low-risk natural concept of probiotics seemed all too distant. As evidence mounts of the attributes of certain probiotic strains to treat diarrhea and reduce the risk of urogenital and other diseases, the developing world has failed to embrace it, support its evaluation and implementation, and take it to where it is needed the most. In this review, the case for and against probiotics for urogenital and intestinal infections is presented based on current literature. The story is far from complete, but the potential for improving the health of the mother and child is significant. United Nations and World Health Organization guidelines have now been developed to vanquish the unproved marketing hype products that have given probiotics a bad name. It is now up to science to deliver the remedies, and to society to make sure that only proven products reach the marketplace and the people in most need.

Female↗

Receptivity for probiotic products among premenopausal female students in an African university.

OBJECTIVE: The objective of this study was to examine the receptivity for probiotic products among premenopausal female students in an African university. GOAL: The goal of this study was to determine the local knowledge in Nigeria of probiotics and the willingness of young women to use them should they be introduced. STUDY: Closed-ended questionnaires were administered to a sample of 280 participants and these addressed age, marital status, perceived risk of HIV infection for the next 3 years, and history of urogenital infections. The participants were also asked whether they would welcome a probiotic product in oral/vaginal form and in milk-based food products, willingness to purchase and use, how often they would use these products, preference of form, price, and where they would like to buy the products. The second questionnaire was open-ended. It asked the participants to freely list any concerns or worries they had in relation to probiotic products. RESULTS: Of the 280 participants, 55.3% indicated that they believed they were at risk of acquiring HIV within the next 3 years, illustrating the enormity of the problem in Africa and the feelings among women that they cannot easily control sexual relationships and have partners use condoms. Eighty-two percent of the subjects stated they would welcome probiotic products in capsular form for vaginal instillation or to be taken orally to improve vaginal health. Over one third (36%) of women indicated they would be willing to use the probiotic products as part of their daily self-care. One hundred nine (39.6%) respondents were willing to purchase the probiotic products at a reasonable price of 0.08 US dollars per dose, whereas 71.5% were willing to pay up to 0.38 US dollars. Some subjects (25%) raised some concern over safety of probiotics. CONCLUSIONS: The findings revealed that female university students are receptive to probiotic products in Nigeria and indicate strongly a need to consider women's concerns about urogenital health. Furthermore, the study identified a need for appropriate educational materials about probiotics, including benefits and safety information, in an African country suffering severely from the HIV epidemic.

Administration, Intravaginal↗

Probiotics in surgical wound infections: current status.

BACKGROUND: Probiotics--live microorganisms that confer a health benefit when taken in adequate amounts, usually as food supplements--are receiving renewed attention in the medical community. Some have been found to play a role in disease remediation. However, mainstream medicine and science remain divided about the validity of health claims made about them. METHODS: To clarify the potential value of probiotics, we reviewed the scientific data on their role in preventing and treating surgical infections as well as some of our own studies of the effects of certain strains of lactobacilli on surgical implant infections. PRINCIPAL FINDINGS: There is little rigorous evidence that probiotics may be beneficial in the prevention and treatment of wound infections. However, data from 3 clinical trials and from our laboratory indicate that certain strains of probiotic lactobacilli and their byproducts may help reduce infection rates in surgical patients and may ameliorate staphylococcus-related infections of surgical implants. CONCLUSION: Although there is good clinical evidence that certain probiotics may be beneficial in conditions such as diarrheal and inflammatory bowel diseases, more studies are required to apply these concepts to the prevention and treatment of wound and other surgical infections.

Animals↗

Oral use of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 significantly alters vaginal flora: randomized, placebo-controlled trial in 64 healthy women.

Urogenital infections afflict an estimated one billion people each year. The size of this problem and the increased prevalence of multi-drug resistant pathogens make it imperative that alternative remedies be found. A randomized, placebo-controlled trial of 64 healthy women given daily oral capsules of Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14 for 60 days showed no adverse effects. Microscopy analysis showed restoration from asymptomatic bacterial vaginosis microflora to a normal lactobacilli colonized microflora in 37% women during lactobacilli treatment compared to 13% on placebo (P=0.02). Lactobacilli were detected in more women in the lactobacilli-treated group than in the placebo group at 28 day (P=0.08) and 60 day (P=0.05) test points. Culture findings confirmed a significant increase in vaginal lactobacilli at day 28 and 60, a significant depletion in yeast at day 28 and a significant reduction in coliforms at day 28, 60 and 90 for lactobacilli-treated subjects versus controls. The combination of probiotic L. rhamnosus GR-1 and L. fermentum RC-14 is not only safe for daily use in healthy women, but it can reduce colonization of the vagina by potential pathogenic bacteria and yeast.

Administration, Oral↗

The potential for probiotics to prevent bacterial vaginosis and preterm labor.

Infections of the urogenital tract in women represent a major burden on the quality of life of women and on the health care system of Canada and other countries. Complications arising from bacterial vaginosis (BV) include increased risk of sexually transmitted diseases including human immunodeficiency virus and elevated risk of preterm birth (PTB). Pharmaceutical interventions, such as antibiotics, have been suboptimally effective and have failed to reduce the incidence of PTB. The absence of lactobacilli in the vagina, a specific feature of BV, raises the question as to whether restoration of lactobacilli, by probiotic therapy, can restore the normal flora and improve the chances of having a healthy term pregnancy. The rationale for probiotic use in pregnant women is quite strong. Certain lactobacilli strains can safely colonize the vagina after oral and vaginal administration, displace and kill pathogens including Gardnerella vaginalis and Escherichia coli, and modulate the immune response to interfere with the inflammatory cascade that leads to PTB. Additional attributes of probiotics include their potential to degrade lipids and enhance cytokine levels, which promote embryo development. In a society that focuses on disease rather than health and drug therapy rather than natural preventive measures, it will take some effort to get remedies such as probiotics into mainstream care. Perhaps the escalating health care budgets and emergence of "superbugs" will provide the incentives to put in place clinical trials designed to evaluate how best to use the commensal organisms that, after all, make up more of our body than human cells, and without which none of us would survive.

Female↗

Oxalate-degrading enzymes from Oxalobacter formigenes: a novel device coating to reduce urinary tract biomaterial-related encrustation.

BACKGROUND AND PURPOSE: The long-term placement of biomaterials within the urinary tract is limited by the development of encrustation. In a noninfected urinary environment, encrustation often results from the deposition of calcium oxalate on the biomaterial surface. There is an association between the absence of Oxalobacter formigenes, a commensal colonic bacterium capable of degrading oxalate, and calcium oxalate stone formation. This pilot study was designed to evaluate several oxalate-degrading enzymes produced by O. formigenes as a potential biomaterial coating to reduce urinary tract encrustation. MATERIALS AND METHODS: Circular silicone disks of 6-mm diameter were incubated for 48 hours in oxalylcoenzyme A decarboxylase (OXC), formyl-coenzyme A transferase (FRC), and coenzyme A, while control disks were incubated in distilled water. The adsorption of OXC and FRC was assessed using enhanced chemiluminescence (ECL) and atomic force microscopy (AFM). Coated and uncoated disks (20 of each) were implanted in the bladders of 40 female New Zealand White rabbits. After 30 days, the disks were recovered, and the degree of encrustation on the polymer surface was evaluated utilizing dry weight measurement, calcium atomic absorption spectroscopy (AAS), and scanning electron microscopy/energy-dispersive X-ray analysis (SEM/EDX). RESULTS: Both ECL and AFM demonstrated coating of the silicone disks with OXC and FRC. The mean dry weights of the coated and control disks following explantation were 0.591 +/- 0.438 g and 0.747 +/- 0.428 g, respectively (P = 0.307). The mean weight of calcium on the coated and control disks, as determined by AAS, was 154.1 +/- 96.25 mg and 258 +/- 181.35 mg, respectively (P = 0.008). CONCLUSIONS: The use of oxalate-degrading enzymes from O. formigenes to coat urinary biomaterials represents a novel paradigm to reduce biomaterial-related encrustation. Coating of silicone with oxalate-degrading enzymes from O. formigenes results in a modest reduction in encrustation with no apparent toxicity. Further studies are warranted.

Animals↗