Gregor Reid - Academia.edu (original) (raw)

Papers by Gregor Reid

Canadian Journal of Microbiology, 1988

Previous investigations have shown that certain strains of lactobacilli can competitively exclude... more Previous investigations have shown that certain strains of lactobacilli can competitively exclude uropathogens from attaching to uroepithelial cells and from causing urinary tract infection in animals. The finding of an inhibitory effect produced by Lactobacillus casei ssp. rhamnosus GR-1 against the growth of uropathogens was investigated further using two Escherichia coli indicator strains Hu 734 and ATCC 25922. There were two phases to the inhibitor studies. The first one using an agar sandwich technique showed that the inhibitor activity was heat stable and inhibitory to the E. coli. The second phase showed that MRS broth provided optimum lactobacilli growth and inhibitor production. In addition, the inhibition was present under conditions buffering for acid and pH. The data indicated that the inhibitory effect was not due to bacteriophages or hydrogen peroxide. Strain GR-1 was found to coaggregate with E. coli ATCC 25922 in urine, a phenomenon that has not previously been reported for urogenital bacteria. An in vitro assay system was developed to study the coaggregation of various lactobacilli and uropathogens. The results demonstrated that highest coaggregation scores occurred after 4 h incubation at 37 degrees C with lactobacilli and two type-1 fimbriated E. coli strains. Of the nine lactobacilli strains tested, each was found to coaggregate with 2 or more of the 13 uropathogens. The dominance of inhibitor-producing lactobacilli on the urogenital epithelium and the ability of these organisms to interact closely with uropathogens would constitute an important host defense mechanism against infection.

Canadian Journal of Microbiology, 1988

Recent studies have shown that certain lactobacilli strains have the ability to interfere with th... more Recent studies have shown that certain lactobacilli strains have the ability to interfere with the adherence and growth of uropathogenic bacteria. This interaction is believed to be important in the maintenance of a normal urogenital flora and in the prevention of infection in females. In the present study, Lactobacillus casei ssp. rhamnosus GR-1 and Lactobacillus acidophilus 76 were found to exert an inhibitory effect on pyelonephritogenic mutant Escherichia coli Hu 734 and E. coli ATCC 25922. The bioactivity of the inhibitor produced by strain GR-1 was retained under pH buffered conditions and was bactericidal. The bioactive substance was heat labile, not precipitated by up to 80% ammonium sulphate, and extractable in chloroform. The data indicated that the inhibitor is not lactic acid or hydrogen peroxide and has a molecular weight greater than 12,000-14,000. Human urine supported production of the inhibitor and reduced and delayed outgrowth of the E. coli. The ability of L. casei GR-1 and possibly other lactobacilli strains to produce inhibitors of uropathogenic bacteria may have clinical importance and significance in the microbial ecology of the urogenital tract.

Journal of Clinical Pharmacology, 1999

Microbial adhesion and biofilm formation on medical devices represent a common occurrence that ca... more Microbial adhesion and biofilm formation on medical devices represent a common occurrence that can lead to serious illness and death. The process by which bacteria and yeast colonize open and closed implants is fairly complicated and involves a series of steps commencing with deposition of host substances onto the material. Prevention and treatment of established biofilms with antimicrobial agents are difficult because the organisms are encased within a protected microenvironment. Efforts to reduce adhesion using specially developed materials, such as hydrophilic or heparin coated, have had modest success once applied to the patient. The reason, at least for the most part, is the diverse milieu into which devices are placed and the multitude of ways in which organisms can colonize surfaces. A better understanding of the process is required, and the knowledge gained must be used to devise new strategies as alternatives to the traditional employment of antibiotics. These new approaches may still use antibiotics but at different concentrations (low to prevent and high to treat infection) and in a different manner (perhaps spiked therapy in which there is a delay between doses to reduce the risk of drug resistance and impact on normal flora). The possibility of applying functional foods to patient management should also be pursued.

Canadian Journal of Microbiology, 1999

In this study, urine was collected from groups of volunteers following the consumption of water, ... more In this study, urine was collected from groups of volunteers following the consumption of water, ascorbic acid, or cranberry supplements. Only ascorbic acid intake consistently produced acidic urine. Photospectroscopy data indicated that increased water consumption produced urine with lower protein content. Surface tension measurements of the collected urine showed that both water and cranberry supplementation consistently produced urine with surface tensions higher than the control or urine collected following ascorbic acid intake. These urine samples were also employed to study uropathogen adhesion to silicone rubber in a parallel plate flow chamber. Urine obtained after ascorbic acid or cranberry supplementation reduced the initial deposition rates and numbers of adherent Escherichia coli and Enterococcus faecalis, but not Pseudomonas aeruginosa, Staphylococcus epidermidis, or Candida albicans. Conversely, urine obtained from subjects with increased water intake vastly increased the initial deposition rates and numbers of adherent E. coli and E. faecalis (P < 0.05).

Fems Immunology and Medical Microbiology, 2001

Forty-two healthy women were randomized to receive one of three encapsulated Lactobacillus rhamno... more Forty-two healthy women were randomized to receive one of three encapsulated Lactobacillus rhamnosus GR-1 plus Lactobacillus fermentum RC-14 probiotic dosage regimens or L. rhamnosus GG by mouth each day for 28 days. However, the vaginal flora, assessed by Nugent scoring, was only normal in 40% of the cases, and 14 patients had asymptomatic bacterial vaginosis. Treatment with L. rhamnosus GR-1/L. fermentum RC-14 once and twice daily correlated with a healthy vaginal flora in up to 90% of patients, and 7/11 patients with bacterial vaginosis converted to normal or intermediate scores within 1 month. Ingestion of L. rhamnosus GG failed to have an effect. This study confirms the potential efficacy of orally administered lactobacilli as a non-chemotherapeutic means to restore and maintain a normal urogenital flora, and shows that over 10 8 viable organisms per day is the required dose. ß

Fems Microbiology Letters, 2000

Several studies have indicated that the capture of nematodes by the nematophagous fungus Arthrobo... more Several studies have indicated that the capture of nematodes by the nematophagous fungus Arthrobotrys oligospora is mediated by a lectin on the fungal surface. One of the major surface proteins of this fungus showed haemagglutinating activity and was isolated by affinity chromatography using a mucin Sepharose column. Biochemical analysis showed that the protein was a dimeric glycoprotein with a molecular mass of 36 kDa and an isoelectric point of pH 6.5, and contained no sulphur amino acids. The protein was N-terminally blocked; four internal peptides were sequenced, and showed no significant similarity to sequences in the Swiss-Prot or PIR databases. The haemagglutinating activity of the isolated protein was not inhibited by any of the mono-or disaccharides tested, but it was inhibited by the glycoproteins fetuin and much The haemagglutinating activity changed after incubating the protein in buffers of different pH, with maximal activity at pH 11.0 and no activity at pH 2.8. The lectin was tested for different enzymic activities but none were detected. Analysis of the haemagglutinating activity in various cell fractions indicated that the protein was associated with extracellular polymer layers and with the cell wall of the fungus. About the same amount of the haemagglutinating protein was recovered from samples of vegetative mycelium and of mycelium containing nematode-trapping cells.

Journal of Medical Microbiology, 1998

The ability of the Lactobacillus acidophilus RC14 biosurfactant 'surlactin' to inhibit the initia... more The ability of the Lactobacillus acidophilus RC14 biosurfactant 'surlactin' to inhibit the initial adhesion of various uropathogenic bacteria and two yeast strains to silicone rubber was investigated in a parallel-plate flow chamber in filter-sterilised pooled human urine. A parallel-plate flow chamber with a silicone rubber bottom plate was filled with a 1.0 mg/ml biosurfactant solution for adsorption overnight (18 h). Subsequently, the adhesion of the bacterial or yeast cells from a urine suspension under low flow (shear rate 15 s-l) was followed in situ by automated image analysis. Control tests were with untreated silicone rubber. Initial deposition rates and numbers of adhering cells after 4 h of flow were determined. Surlactin layers caused a marked inhibition of the initial deposition rates and adhesion numbers after 4 h for the majority of the bacteria (11 of 15 strains tested) and this inhibition was particularly effective against Enterococcus faecalis, Escherichia coli and Staphylococcus epidermidis. Although the initial deposition rates of the two Candida albicans strains were reduced by c. 50% in comparison with the controls, the numbers of yeast cells adhering after 4 h were similar.

Fems Immunology and Medical Microbiology, 2003

Urogenital infections afflict an estimated one billion people each year. The size of this problem... more Urogenital infections afflict an estimated one billion people each year. The size of this problem and the increased prevalence of multidrug 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.

Fems Immunology and Medical Microbiology, 2001

We report the first clinical evidence that probiotic lactobacilli can be delivered to the vagina ... more We report the first clinical evidence that probiotic lactobacilli can be delivered to the vagina following oral intake. In 10 women with a history of recurrent yeast vaginitis, bacterial vaginosis (BV) and urinary tract infections, strains Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14 suspended in skim milk and given twice daily for 14 days, were recovered from the vagina and identified by morphology and molecular typing within 1 week of commencement of therapy. In six cases of asymptomatic BV or intermediate BV (based upon Nugent scoring) was resolved within 1 week of therapy.

Fems Immunology and Medical Microbiology, 1996

It was hypothesized that Lactobucillus acidophilus might not be the dominant aerobic or microaero... more It was hypothesized that Lactobucillus acidophilus might not be the dominant aerobic or microaerophilic Luctobacillus species in the human vagina, and that the dominant isolates are likely to express a variety of properties associated with colonization. To examine the question, vaginal swabs were collected from 100 healthy premenopausal women and cultured to detect the dominant aerobic or microaerophilic isolates of Imtobacillus. Only eight species were detected, with Luctobacillus jensenii blaing the dominant colonizers in the highest number (35) of women. Twelve different plasmid profiles were found amongst the isolates, but there was no association between plasmids and vaginal colonization or hydrogen peroxide production. Of the strains tested, few were resistant to the spermicidal agent noaoxynol-9. The data identify species within which strains may possess properties associated with maintenance of a healthy vaginal ecology

... 2002;287(15):1940-1941. doi: 10.1001/jama.287.15.1940. Lactobacillus Strains and VaginalEcolo... more ... 2002;287(15):1940-1941. doi: 10.1001/jama.287.15.1940. Lactobacillus Strains and VaginalEcology. ... The culture fluid was aspirated and fresh media added for either 20 hours (VSV) or 48 hours (Ad5). A plaque assay was then performed to measure viral infectivity. ...

The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradien... more The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradient gel electrophoresis (DGGE) and sequencing of the V2-V3 region of the 16S rRNA gene. Ten of the women were studied further to investigate the effect and persistence of vaginally inserted capsules containing viable lactobacilli. PCR-DGGE indicated that most subjects had a microbiota represented by one to three dominant DNA fragments. Analysis of these fragments revealed that 79% of the women possessed sequences with high levels of similarity to Lactobacillus species sequences. Sequences homologous to Lactobacillus iners sequences were the most common and were detected in 42% of the women tested. Alteration of the vaginal microbiota could be detected by PCR-DGGE in several women after the instillation of lactobacilli. Additionally, randomly amplified polymorphic DNA analysis of lactobacilli isolated from selective media demonstrated that the exogenous strains could be detected for up to 21 days in some subjects. This study demonstrates that non-culture-based techniques, such as PCR-DGGE, are useful adjuncts for studies of the vaginal microbiota.

To monitor the bacterial vaginal microflora of postmenopausal women, several approaches were used... more To monitor the bacterial vaginal microflora of postmenopausal women, several approaches were used: (1) Nugent scoring of Gram-stained smears from vaginal swabs; (2) testing for bacteria, using specific polymerase chain reaction (PCR) primers; (3) PCR-denaturing gradient gel electrophoresis (DGGE) analysis of total bacterial DNA, amplified using eubacterial and Lactobacillus-specific primers; and (4) sequence analysis of amplified DNA fragments of interest from denaturing gradient gels. Of 20 women studied, 70% had either intermediate-grade bacterial colonization or bacterial vaginosis (BV), as defined by Nugent criteria, at the first sampling point. Subjects with normal Nugent scores had у1 species of Lactobacillus detected by sequencing of dominant DNA fragments from denaturing gradient gels generated using eubacterial primers. Samples from women with Nugent scores that indicated BV had varied bacterial DGGE profiles, which emphasizes the diverse nature of such infections. This study indicates that asymptomatic BV appears to be much more common than is currently perceived; these findings may have implications for the health of postmenopausal women.

Trends in Microbiology, 2001

This review focuses on the use and potential of Lactobacillus to prevent infections of the urogen... more This review focuses on the use and potential of Lactobacillus to prevent infections of the urogenital and intestinal tracts. The presence and dominance of Lactobacillus in the vagina is associated with a reduced risk of bacterial vaginosis and urinary tract infections. The mechanisms appear to involve anti-adhesion factors, by-products such as hydrogen peroxide and bacteriocins lethal to pathogens, and perhaps immune modulation or signaling effects. The instillation of Lactobacillus GR-1 and B-54 or RC-14 strains into the vagina has been shown to reduce the risk of urinary tract infections, and improve the maintenance of a normal flora. Ingestion of these strains into the gut has also been shown to modify the vaginal flora to a more healthy state. In addition, these strains inhibit the growth of intestinal, as well as urogenital pathogens, colonize the gut and protect against infections as shown in mice. Other probiotic strains, such as Lactobacillus GG, have been shown to prevent and treat gastroenteritis caused by rotavirus and bacteria. Given that lactobacilli are not the dominant commensals in a gut which comprises around 10 10 organisms, much work is still needed to define the mechanisms whereby GR-1, RC-14, GG and other strains contribute to health restoration and maintenance. Such critically important studies will require the medical science community to show a willingness to turn away from pharmaceutical remedies as the only solution to health and disease.

Recent advances in our understanding of the community structure and function of the human microbi... more Recent advances in our understanding of the community structure and function of the human microbiome have implications for the potential role of probiotics and prebiotics in promoting human health. A group of experts recently met to review the latest advances in microbiota/microbiome research and discuss the implications for development of probiotics and prebiotics, primarily as they relate to effects mediated via the intestine. The goals of the meeting were to share recent advances in research on the microbiota, microbiome, probiotics, and prebiotics, and to discuss these findings in the contexts of regulatory barriers, evolving healthcare environments, and potential effects on a variety of health topics, including the development of obesity and diabetes; the long-term consequences of exposure to antibiotics early in life to the gastrointestinal (GI) microbiota; lactose intolerance; and the relationship between the GI microbiota and the central nervous system, with implications for depression, cognition, satiety, and mental health for people living in developed and developing countries. This report provides an overview of these discussions.

Canadian Journal of Microbiology, 1988

Previous investigations have shown that certain strains of lactobacilli can competitively exclude... more Previous investigations have shown that certain strains of lactobacilli can competitively exclude uropathogens from attaching to uroepithelial cells and from causing urinary tract infection in animals. The finding of an inhibitory effect produced by Lactobacillus casei ssp. rhamnosus GR-1 against the growth of uropathogens was investigated further using two Escherichia coli indicator strains Hu 734 and ATCC 25922. There were two phases to the inhibitor studies. The first one using an agar sandwich technique showed that the inhibitor activity was heat stable and inhibitory to the E. coli. The second phase showed that MRS broth provided optimum lactobacilli growth and inhibitor production. In addition, the inhibition was present under conditions buffering for acid and pH. The data indicated that the inhibitory effect was not due to bacteriophages or hydrogen peroxide. Strain GR-1 was found to coaggregate with E. coli ATCC 25922 in urine, a phenomenon that has not previously been reported for urogenital bacteria. An in vitro assay system was developed to study the coaggregation of various lactobacilli and uropathogens. The results demonstrated that highest coaggregation scores occurred after 4 h incubation at 37 degrees C with lactobacilli and two type-1 fimbriated E. coli strains. Of the nine lactobacilli strains tested, each was found to coaggregate with 2 or more of the 13 uropathogens. The dominance of inhibitor-producing lactobacilli on the urogenital epithelium and the ability of these organisms to interact closely with uropathogens would constitute an important host defense mechanism against infection.

Canadian Journal of Microbiology, 1988

Recent studies have shown that certain lactobacilli strains have the ability to interfere with th... more Recent studies have shown that certain lactobacilli strains have the ability to interfere with the adherence and growth of uropathogenic bacteria. This interaction is believed to be important in the maintenance of a normal urogenital flora and in the prevention of infection in females. In the present study, Lactobacillus casei ssp. rhamnosus GR-1 and Lactobacillus acidophilus 76 were found to exert an inhibitory effect on pyelonephritogenic mutant Escherichia coli Hu 734 and E. coli ATCC 25922. The bioactivity of the inhibitor produced by strain GR-1 was retained under pH buffered conditions and was bactericidal. The bioactive substance was heat labile, not precipitated by up to 80% ammonium sulphate, and extractable in chloroform. The data indicated that the inhibitor is not lactic acid or hydrogen peroxide and has a molecular weight greater than 12,000-14,000. Human urine supported production of the inhibitor and reduced and delayed outgrowth of the E. coli. The ability of L. casei GR-1 and possibly other lactobacilli strains to produce inhibitors of uropathogenic bacteria may have clinical importance and significance in the microbial ecology of the urogenital tract.

Journal of Clinical Pharmacology, 1999

Microbial adhesion and biofilm formation on medical devices represent a common occurrence that ca... more Microbial adhesion and biofilm formation on medical devices represent a common occurrence that can lead to serious illness and death. The process by which bacteria and yeast colonize open and closed implants is fairly complicated and involves a series of steps commencing with deposition of host substances onto the material. Prevention and treatment of established biofilms with antimicrobial agents are difficult because the organisms are encased within a protected microenvironment. Efforts to reduce adhesion using specially developed materials, such as hydrophilic or heparin coated, have had modest success once applied to the patient. The reason, at least for the most part, is the diverse milieu into which devices are placed and the multitude of ways in which organisms can colonize surfaces. A better understanding of the process is required, and the knowledge gained must be used to devise new strategies as alternatives to the traditional employment of antibiotics. These new approaches may still use antibiotics but at different concentrations (low to prevent and high to treat infection) and in a different manner (perhaps spiked therapy in which there is a delay between doses to reduce the risk of drug resistance and impact on normal flora). The possibility of applying functional foods to patient management should also be pursued.

Canadian Journal of Microbiology, 1999

In this study, urine was collected from groups of volunteers following the consumption of water, ... more In this study, urine was collected from groups of volunteers following the consumption of water, ascorbic acid, or cranberry supplements. Only ascorbic acid intake consistently produced acidic urine. Photospectroscopy data indicated that increased water consumption produced urine with lower protein content. Surface tension measurements of the collected urine showed that both water and cranberry supplementation consistently produced urine with surface tensions higher than the control or urine collected following ascorbic acid intake. These urine samples were also employed to study uropathogen adhesion to silicone rubber in a parallel plate flow chamber. Urine obtained after ascorbic acid or cranberry supplementation reduced the initial deposition rates and numbers of adherent Escherichia coli and Enterococcus faecalis, but not Pseudomonas aeruginosa, Staphylococcus epidermidis, or Candida albicans. Conversely, urine obtained from subjects with increased water intake vastly increased the initial deposition rates and numbers of adherent E. coli and E. faecalis (P < 0.05).

Fems Immunology and Medical Microbiology, 2001

Forty-two healthy women were randomized to receive one of three encapsulated Lactobacillus rhamno... more Forty-two healthy women were randomized to receive one of three encapsulated Lactobacillus rhamnosus GR-1 plus Lactobacillus fermentum RC-14 probiotic dosage regimens or L. rhamnosus GG by mouth each day for 28 days. However, the vaginal flora, assessed by Nugent scoring, was only normal in 40% of the cases, and 14 patients had asymptomatic bacterial vaginosis. Treatment with L. rhamnosus GR-1/L. fermentum RC-14 once and twice daily correlated with a healthy vaginal flora in up to 90% of patients, and 7/11 patients with bacterial vaginosis converted to normal or intermediate scores within 1 month. Ingestion of L. rhamnosus GG failed to have an effect. This study confirms the potential efficacy of orally administered lactobacilli as a non-chemotherapeutic means to restore and maintain a normal urogenital flora, and shows that over 10 8 viable organisms per day is the required dose. ß

Fems Microbiology Letters, 2000

Several studies have indicated that the capture of nematodes by the nematophagous fungus Arthrobo... more Several studies have indicated that the capture of nematodes by the nematophagous fungus Arthrobotrys oligospora is mediated by a lectin on the fungal surface. One of the major surface proteins of this fungus showed haemagglutinating activity and was isolated by affinity chromatography using a mucin Sepharose column. Biochemical analysis showed that the protein was a dimeric glycoprotein with a molecular mass of 36 kDa and an isoelectric point of pH 6.5, and contained no sulphur amino acids. The protein was N-terminally blocked; four internal peptides were sequenced, and showed no significant similarity to sequences in the Swiss-Prot or PIR databases. The haemagglutinating activity of the isolated protein was not inhibited by any of the mono-or disaccharides tested, but it was inhibited by the glycoproteins fetuin and much The haemagglutinating activity changed after incubating the protein in buffers of different pH, with maximal activity at pH 11.0 and no activity at pH 2.8. The lectin was tested for different enzymic activities but none were detected. Analysis of the haemagglutinating activity in various cell fractions indicated that the protein was associated with extracellular polymer layers and with the cell wall of the fungus. About the same amount of the haemagglutinating protein was recovered from samples of vegetative mycelium and of mycelium containing nematode-trapping cells.

Journal of Medical Microbiology, 1998

The ability of the Lactobacillus acidophilus RC14 biosurfactant 'surlactin' to inhibit the initia... more The ability of the Lactobacillus acidophilus RC14 biosurfactant 'surlactin' to inhibit the initial adhesion of various uropathogenic bacteria and two yeast strains to silicone rubber was investigated in a parallel-plate flow chamber in filter-sterilised pooled human urine. A parallel-plate flow chamber with a silicone rubber bottom plate was filled with a 1.0 mg/ml biosurfactant solution for adsorption overnight (18 h). Subsequently, the adhesion of the bacterial or yeast cells from a urine suspension under low flow (shear rate 15 s-l) was followed in situ by automated image analysis. Control tests were with untreated silicone rubber. Initial deposition rates and numbers of adhering cells after 4 h of flow were determined. Surlactin layers caused a marked inhibition of the initial deposition rates and adhesion numbers after 4 h for the majority of the bacteria (11 of 15 strains tested) and this inhibition was particularly effective against Enterococcus faecalis, Escherichia coli and Staphylococcus epidermidis. Although the initial deposition rates of the two Candida albicans strains were reduced by c. 50% in comparison with the controls, the numbers of yeast cells adhering after 4 h were similar.

Fems Immunology and Medical Microbiology, 2003

Urogenital infections afflict an estimated one billion people each year. The size of this problem... more Urogenital infections afflict an estimated one billion people each year. The size of this problem and the increased prevalence of multidrug 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.

Fems Immunology and Medical Microbiology, 2001

We report the first clinical evidence that probiotic lactobacilli can be delivered to the vagina ... more We report the first clinical evidence that probiotic lactobacilli can be delivered to the vagina following oral intake. In 10 women with a history of recurrent yeast vaginitis, bacterial vaginosis (BV) and urinary tract infections, strains Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14 suspended in skim milk and given twice daily for 14 days, were recovered from the vagina and identified by morphology and molecular typing within 1 week of commencement of therapy. In six cases of asymptomatic BV or intermediate BV (based upon Nugent scoring) was resolved within 1 week of therapy.

Fems Immunology and Medical Microbiology, 1996

It was hypothesized that Lactobucillus acidophilus might not be the dominant aerobic or microaero... more It was hypothesized that Lactobucillus acidophilus might not be the dominant aerobic or microaerophilic Luctobacillus species in the human vagina, and that the dominant isolates are likely to express a variety of properties associated with colonization. To examine the question, vaginal swabs were collected from 100 healthy premenopausal women and cultured to detect the dominant aerobic or microaerophilic isolates of Imtobacillus. Only eight species were detected, with Luctobacillus jensenii blaing the dominant colonizers in the highest number (35) of women. Twelve different plasmid profiles were found amongst the isolates, but there was no association between plasmids and vaginal colonization or hydrogen peroxide production. Of the strains tested, few were resistant to the spermicidal agent noaoxynol-9. The data identify species within which strains may possess properties associated with maintenance of a healthy vaginal ecology

... 2002;287(15):1940-1941. doi: 10.1001/jama.287.15.1940. Lactobacillus Strains and VaginalEcolo... more ... 2002;287(15):1940-1941. doi: 10.1001/jama.287.15.1940. Lactobacillus Strains and VaginalEcology. ... The culture fluid was aspirated and fresh media added for either 20 hours (VSV) or 48 hours (Ad5). A plaque assay was then performed to measure viral infectivity. ...

The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradien... more The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradient gel electrophoresis (DGGE) and sequencing of the V2-V3 region of the 16S rRNA gene. Ten of the women were studied further to investigate the effect and persistence of vaginally inserted capsules containing viable lactobacilli. PCR-DGGE indicated that most subjects had a microbiota represented by one to three dominant DNA fragments. Analysis of these fragments revealed that 79% of the women possessed sequences with high levels of similarity to Lactobacillus species sequences. Sequences homologous to Lactobacillus iners sequences were the most common and were detected in 42% of the women tested. Alteration of the vaginal microbiota could be detected by PCR-DGGE in several women after the instillation of lactobacilli. Additionally, randomly amplified polymorphic DNA analysis of lactobacilli isolated from selective media demonstrated that the exogenous strains could be detected for up to 21 days in some subjects. This study demonstrates that non-culture-based techniques, such as PCR-DGGE, are useful adjuncts for studies of the vaginal microbiota.

To monitor the bacterial vaginal microflora of postmenopausal women, several approaches were used... more To monitor the bacterial vaginal microflora of postmenopausal women, several approaches were used: (1) Nugent scoring of Gram-stained smears from vaginal swabs; (2) testing for bacteria, using specific polymerase chain reaction (PCR) primers; (3) PCR-denaturing gradient gel electrophoresis (DGGE) analysis of total bacterial DNA, amplified using eubacterial and Lactobacillus-specific primers; and (4) sequence analysis of amplified DNA fragments of interest from denaturing gradient gels. Of 20 women studied, 70% had either intermediate-grade bacterial colonization or bacterial vaginosis (BV), as defined by Nugent criteria, at the first sampling point. Subjects with normal Nugent scores had у1 species of Lactobacillus detected by sequencing of dominant DNA fragments from denaturing gradient gels generated using eubacterial primers. Samples from women with Nugent scores that indicated BV had varied bacterial DGGE profiles, which emphasizes the diverse nature of such infections. This study indicates that asymptomatic BV appears to be much more common than is currently perceived; these findings may have implications for the health of postmenopausal women.

Trends in Microbiology, 2001

This review focuses on the use and potential of Lactobacillus to prevent infections of the urogen... more This review focuses on the use and potential of Lactobacillus to prevent infections of the urogenital and intestinal tracts. The presence and dominance of Lactobacillus in the vagina is associated with a reduced risk of bacterial vaginosis and urinary tract infections. The mechanisms appear to involve anti-adhesion factors, by-products such as hydrogen peroxide and bacteriocins lethal to pathogens, and perhaps immune modulation or signaling effects. The instillation of Lactobacillus GR-1 and B-54 or RC-14 strains into the vagina has been shown to reduce the risk of urinary tract infections, and improve the maintenance of a normal flora. Ingestion of these strains into the gut has also been shown to modify the vaginal flora to a more healthy state. In addition, these strains inhibit the growth of intestinal, as well as urogenital pathogens, colonize the gut and protect against infections as shown in mice. Other probiotic strains, such as Lactobacillus GG, have been shown to prevent and treat gastroenteritis caused by rotavirus and bacteria. Given that lactobacilli are not the dominant commensals in a gut which comprises around 10 10 organisms, much work is still needed to define the mechanisms whereby GR-1, RC-14, GG and other strains contribute to health restoration and maintenance. Such critically important studies will require the medical science community to show a willingness to turn away from pharmaceutical remedies as the only solution to health and disease.

Recent advances in our understanding of the community structure and function of the human microbi... more Recent advances in our understanding of the community structure and function of the human microbiome have implications for the potential role of probiotics and prebiotics in promoting human health. A group of experts recently met to review the latest advances in microbiota/microbiome research and discuss the implications for development of probiotics and prebiotics, primarily as they relate to effects mediated via the intestine. The goals of the meeting were to share recent advances in research on the microbiota, microbiome, probiotics, and prebiotics, and to discuss these findings in the contexts of regulatory barriers, evolving healthcare environments, and potential effects on a variety of health topics, including the development of obesity and diabetes; the long-term consequences of exposure to antibiotics early in life to the gastrointestinal (GI) microbiota; lactose intolerance; and the relationship between the GI microbiota and the central nervous system, with implications for depression, cognition, satiety, and mental health for people living in developed and developing countries. This report provides an overview of these discussions.