Publications (27)52.95 Total impact
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Article: Bacteroides clarus sp. nov., Bacteroides fluxus sp. nov. and Bacteroides oleiciplenus sp. nov., isolated from human faeces.
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ABSTRACT: Three Gram-stain-negative, obligately anaerobic, non-spore-forming, rod-shaped bacteria (strains YIT 12056T, YIT 12057T and YIT 12058T) were isolated from human faeces. These strains were characterized by phylogenetic analyses based on 16S rRNA gene sequence and phenotypic tests. 16S rRNA gene sequence analyses revealed that strains YIT 12056T, YIT 12057T and YIT 12058T were most closely related to the type strains of Bacteroides gallinarum, Bacteroides uniformis and Bacteroides intestinalis with approximate similarity values of 96.6, 95.0 and 96.7%, respectively. The DNA G+C contents of the novel strains were 45.3 (YIT 12056T), 45.2 (YIT 12057T) and 43.6 mol% (YIT 12058T) and the major respiratory quinones of all three isolates were menaquinones MK-10 and MK-11. These properties were typical for members of the genus Bacteroides. The results of the other phenotypic analyses also supported the affiliation of these strains to the genus Bacteroides. The 16S rRNA gene sequence analysis, analysis of the major cellular fatty acids and other biochemical tests enabled the genotypic and phenotypic differentiation of the three new strains. Based on these data, three novel species, Bacteroides clarus sp. nov., Bacteroides fluxus sp. nov. and Bacteroides oleiciplenus sp. nov. are proposed. The type strains of B. clarus, B. fluxus and B. oleiciplenus are YIT 12056T (=JCM 16067T=DSM 22519T), YIT 12057T (=JCM 16101T=DSM 22534T) and YIT 12058T (=JCM 16102T=DSM 22535T), respectively.International journal of systematic and evolutionary microbiology 09/2009; 60(Pt 8):1864-9. · 2.27 Impact Factor -
Article: Alistipes indistinctus sp. nov. and Odoribacter laneus sp. nov., common members of the human intestinal microbiota isolated from faeces.
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ABSTRACT: Two anaerobic, non-spore-forming, non-motile, Gram-negative-staining bacteria, strains YIT 12060(T) and YIT 12061(T), were isolated from human faeces. Cells of strain YIT 12060(T) were coccoid to rod-shaped with round ends, positive for catalase, negative for indole and oxidase production, produced succinic and acetic acids as end products of glucose metabolism in peptone/yeast extract/glucose medium and had a DNA G+C content of 55.2 mol%. The main respiratory quinones were MK-10 (40%) and MK-11 (57%). Fatty acid analysis demonstrated the presence of a high concentration of iso-C(15 : 0) (56%). Following 16S rRNA gene sequence analysis, this strain was found to be most closely related to species of the genus Alistipes, with 90.9-92.6% gene sequence similarities to type strains of this species. Phylogenetic analysis and biochemical data supported the affiliation of strain YIT 12060(T) to the genus Alistipes of the family 'Rikenellaceae'. Strain YIT 12060(T) therefore represents a novel species of the genus Alistipes for which the name Alistipes indistinctus sp. nov. is proposed; the type strain is YIT 12060(T) (=DSM 22520(T)=JCM 16068(T)). Cells of the other isolate, strain YIT 12061(T), were pleomorphic rods that were asaccharolytic, catalase- and oxidase-negative, positive for gelatin hydrolysis and indole production, produced small amounts of succinic, acetic and iso-valeric acids as end products of metabolism in peptone/yeast extract medium and had a DNA G+C content of approximately 42.4 mol%. On the basis of 16S rRNA gene sequence similarity values, this strain was shown to belong to the family 'Porphyromonadaceae' and related to the type strains of Odoribacter splanchnicus (89.6%) and Odoribacter denticanis (86.2%); similarity values with strains of recognized species within the family 'Porphyromonadaceae' were less than 84 %. Biochemical data supported the affiliation of strain YIT 12061(T) to the genus Odoribacter. Strain YIT 12061(T) therefore represents a novel species for which the name Odoribacter laneus sp. nov. is proposed; the type strain is YIT 12061(T) (=DSM 22474(T)=JCM 16069(T)).International journal of systematic and evolutionary microbiology 09/2009; 60(Pt 6):1296-302. · 2.27 Impact Factor -
Article: Succinatimonas hippei gen. nov., sp. nov., isolated from human faeces.
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ABSTRACT: A novel strictly anaerobic, non-spore-forming, non-motile, non-flagellated, rod-shaped, Gram-negative bacterium (YIT 12066T) was isolated from human faeces. The isolate was negative for catalase, oxidase, urease, hydrolysis of aesculin and gelatin, nitrate reduction and indole production. The major end products of glucose metabolism were succinate and acetate. The major cellular fatty acids (>10%) were C14:0, C18:1omega7c, C18:1omega9c, C16:1omega7c and C16:0. The G+C content of the DNA was 40.3 mol%. 16S rRNA gene sequence analysis showed that strain YIT 12066T was most closely related to members of the family Succinivibrionaceae, with sequence similarity of 92-87%. However, some phenotypic characteristics such as cellular morphology and the major fatty acid profile of strain YIT 12066T were markedly different from those of other members of the family Succinivibrionaceae. On the basis of both phylogenetic and phenotypic evidence, it is suggested that strain YIT 12066T represents a novel species in a new genus, for which the name Succinatimonas hippei gen. nov., sp. nov. is proposed; the type strain of Succinatimonas hippei is YIT 12066T (=DSM 22608T =JCM 16073T).International journal of systematic and evolutionary microbiology 09/2009; 60(Pt 8):1788-93. · 2.27 Impact Factor -
Article: Early use of probiotics is important therapy in infants with severe congenital anomaly.
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ABSTRACT: Infants with severe congenital anomaly often need to undergo operation followed by antibiotic therapy. As a result they inevitably acquire abnormal intestinal microbiota, which cause severe infections such as necrotizing enterocolitis. Also, intestinal function deteriorates and their nutritional state is very poor. In order to prevent these situations probiotic therapy is proposed as an effective supporting treatment. Probiotic therapy were therefore applied to infants with severe congenital anomaly as early as possible to ascertain its efficacy. As probiotics, two bacteria were used: Bifidobacterium breve Yakult and Lactobacillus casei Shirota. Probiotic therapy was used in four infants with severe congenital anomaly as early as possible after surgery. Their intestinal microbiota and physical growth were followed through the treatment course. Two patients suffered from meconium peritonitis with ileal atresia. One patient was born with complex anomalies (omphalocele, bladder exstrophy, myelomeningocele). The fourth patient suffered from complete urorectal septum malformation. The intestinal microbiota of these four patients was first induced to be probiotic dominant and finally changed to commensal anaerobe dominant that was similar to normal intestinal microbiota. Pathogenic bacteria were seldom detected. The patients' physical growth was excellent despite short bowel and pulmonary hypoplasia. Probiotic therapy was effective in inducing probiotic dominant intestinal microbiota and normal intestinal microbiota in infants with severe congenital anomalies. As a result their intestinal absorptive functions were activated and severe infections were completely prevented. All of the infants grew well despite their physical disadvantages.Pediatrics International 09/2009; 52(3):362-7. · 0.63 Impact Factor -
Article: Parasutterella excrementihominis gen. nov., sp. nov., a member of the family Alcaligenaceae isolated from human faeces.
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ABSTRACT: A novel, strictly anaerobic, non-spore-forming, Gram-negative coccobacillus (strain YIT 11859(T)) was isolated from human faeces. Biochemically, this strain was largely unreactive and was asaccharolytic. Growth of strain YIT 11859(T) in peptone-yeast extract broth produced no visible turbidity, and a trace amount of propionate was detected as an end product of metabolism. 16S rRNA gene sequence analysis showed that strain YIT 11859(T) was related most closely to the type strains of Sutterella species, with 90.8-88.0 % sequence similarity. Phylogenetic analysis of these and other related sequences confirmed that strain YIT 11859(T) was phylogenetically most closely associated with Sutterella species, but formed a separate cluster, indicating that strain YIT 11859(T) represents a novel member of the family Alcaligenaceae. Fatty acid analysis demonstrated the presence of a high concentration of C(18 : 1)omega9c (75 % of the total). The main respiratory quinones were menaquinone (MK-6) and methylated menaquinone (MMK-6). The G+C content of the DNA was 49.8 mol%. These results suggest that strain YIT 11859(T) represents a novel species of a new genus, for which the name Parasutterella excrementihominis gen. nov., sp. nov. is proposed. The type strain of Parasutterella excrementihominis is YIT 11859(T) (=DSM 21040(T) =JCM 15078(T)).International journal of systematic and evolutionary microbiology 07/2009; 59(Pt 7):1793-7. · 2.27 Impact Factor -
Article: Paraprevotella clara gen. nov., sp. nov. and Paraprevotella xylaniphila sp. nov., members of the family 'Prevotellaceae' isolated from human faeces.
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ABSTRACT: Two anaerobic, non-spore-forming, pleomorphic, Gram-negative rods, designated YIT 11840T and YIT 11841T, were isolated from human faeces. The organisms were catalase-negative, produced succinic and acetic acids as end products of glucose metabolism and had DNA G+C contents of approximately 48-49 mol%. Although the phenotypic characteristics of these two strains were very similar, analysis of their 16S rRNA gene sequences showed that they are only distantly related (93.8%), indicating that they represent two different species. A comparative sequence analysis revealed that these two species are members of the family 'Prevotellaceae' but are phylogenetically distant (<88% sequence similarity) from the known genera belonging to this family, including Prevotella, Hallela and Xylanibacter. On the basis of the phylogenetic analysis and physiological tests, strains YIT 11840T and YIT 11841T represent two novel species of a new genus, for which the names Paraprevotella clara gen. nov., sp. nov. (type strain YIT 11840T=JCM 14859T=DSM 19731T), the type species, and Paraprevotella xylaniphila sp. nov. (type strain YIT 11841T=JCM 14860T=DSM 19681T) are proposed.International journal of systematic and evolutionary microbiology 07/2009; 59(Pt 8):1895-900. · 2.27 Impact Factor -
Article: Dialister succinatiphilus sp. nov. and Barnesiella intestinihominis sp. nov., isolated from human faeces.
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ABSTRACT: Two anaerobic, non-spore-forming, bacteria (YIT 11850(T) and YIT 11860(T)) that stained Gram-negative, were isolated from human faeces. Cells of strain YIT 11850(T) were coccobacilli, asaccharolytic and largely unreactive, with only traces of lactate and propionate as metabolic end products; however, strain YIT 11850(T) was able to decarboxylate succinate to propionate. The DNA G+C content of strain YIT 11850(T) was 51.9 mol%. Following 16S rRNA gene sequence analysis, this strain was found to be most closely related to Dialister propionicifaciens, with 95.1 % sequence similarity between the two taxa. Biochemical data supported the affiliation of strain YIT 11850(T) to the genus Dialister. Strain YIT 11850(T) therefore represents a novel species for which the name Dialister succinatiphilus sp. nov. is proposed; the type strain is YIT 11850(T) (=DSM 21274(T)=JCM 15077(T)). Cells of the other isolate, strain YIT 11860(T), were non-motile, rod-shaped, positive for aesculin hydrolysis, negative for indole production, produced succinic and acetic acids as end products of glucose metabolism and possessed a DNA G+C content of 45.5 mol%. On the basis of 16S rRNA gene sequence similarity values, this strain was shown to belong to the family 'Porphyromonadaceae' related to Barnesiella viscericola (96.0 %); similarity values with species within the family 'Porphyromonadaceae' with validly published names were less than 86 %. Biochemical data supported the affiliation of strain YIT 11860(T) to the genus Barnesiella. Strain YIT 11860(T) therefore represents a novel species for which the name Barnesiella intestinihominis sp. nov. is proposed; the type strain is YIT 11860(T) (=DSM 21032(T)=JCM 15079(T)).International journal of systematic and evolutionary microbiology 01/2009; 58(Pt 12):2716-20. · 2.27 Impact Factor -
Article: Imbalance in intestinal microflora constitution could be involved in the pathogenesis of inflammatory bowel disease.
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ABSTRACT: Since genetically engineered animal models of inflammatory bowel disease (IBD) do not develop colitis under germ-free conditions, the intestinal microflora is thought to be one of the most important environmental factors associated with IBD. To understand the involvement of intestinal microflora in the pathogenesis of IBD, we analyzed the constituents of intestinal microflora in IBD. Faecal samples from 73 patients with ulcerative colitis (UC) and 23 patients with Crohn's disease (CD) were analyzed by quantitative PCR using 16S rRNA gene-targeted group-specific primers for Bacteroides fragilis group, Bifidobacterium, Clostridium coccoides groups, Clostridium leptum subgroup, Atopobium cluster, and seven species of Bacteroides. We analyzed the distribution of the predominant microflora by fluorescence in situ hybridization (FISH) using group-specific probes. We also examined the concentration of faecal organic acids produced by intestinal microflora. Contrary to previous reports, we found that the B. fragilis group was significantly decreased in the faeces of patients with IBD. Moreover, B. vulgatus was the predominant microflora in healthy controls and relatively decreased among IBD patients. Most of the microflora adhering to the colonic mucosa surrounding the mucus layer comprised C. coccoides group and Bifidobacterium. B. fragilis group mainly inhabited the faeces, but did not adhere to or invade the mucosa. The concentrations of propionic and butyric acids in the faeces were significantly decreased in patients with IBD. These findings indicate that IBD is not caused by a specific intestinal bacterial cluster or species and that disordered intestinal microflora could be involved in the pathogenesis of IBD.International journal of medical microbiology: IJMM 08/2008; 298(5-6):463-72. · 2.80 Impact Factor -
Article: Sutterella parvirubra sp. nov. and Megamonas funiformis sp. nov., isolated from human faeces.
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ABSTRACT: Three strains of anaerobic, non-spore-forming, Gram-negative coccobacilli (YIT 11816T, YIT 11817 and YIT 11818) were isolated from human faeces. On the basis of 16S rRNA gene sequence similarity, these strains were shown to belong to the family Alcaligenaceae and to be related to the type strain of Sutterella stercoricanis (94.9 %) and to Sutterella wadsworthensis WAL 7877 (94.3 %); the similarity to strains of any other species with a validly published name within the family Alcaligenaceae was less than 92 %. Biochemical data supported the affiliation of these strains to the genus Sutterella. These strains therefore represent a novel species, for which the name Sutterella parvirubra sp. nov. is proposed; the type strain is YIT 11816T (=DSM 19354T =JCM 14724T). The cells of another isolate, strain YIT 11815T, were non-spore-forming, Gram-negative, very large rods, 1x5-200 microm in size, with or without a central, subterminal or terminal swelling of 2-4 microm diameter when grown in a broth medium supplemented with glucose. Based on comparative 16S rRNA gene sequencing, this bacterium is a member of the family Acidaminococcaceae, and most closely related to Megamonas hypermegale (95.3 % similarity to the type strain). Interestingly, the 16S rRNA gene sequence of strain YIT 11815T showed 99 % similarity to sequences of uncultured colonic bacteria. A 16S rRNA gene sequence divergence value of >3 % from known cultured species suggested that isolate YIT 11815T represents a novel species, for which the name Megamonas funiformis sp. nov. is proposed; the type strain is YIT 11815T (=DSM 19343T =JCM 14723T).International journal of systematic and evolutionary microbiology 04/2008; 58(Pt 4):970-5. · 2.27 Impact Factor -
Article: Synbiotics reduce postoperative infectious complications: a randomized controlled trial in biliary cancer patients undergoing hepatectomy.
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ABSTRACT: The clinical value of synbiotics in surgical patients remains unclear. The aim of this study was to investigate the effect of synbiotics on intestinal integrity and microflora, as well as on surgical outcome, in patients undergoing high-risk hepatectomy. Fifty-four patients with biliary cancer were randomly allocated to two groups before hepatectomy. One group received postoperative enteral feeding that included synbiotics; the other received enteral feeding only. Lactulose/mannitol (L/M) ratio, serum diamine oxidase (DAO) activity, and fecal microflora and organic acid concentrations were determined. Postoperative infectious complications were recorded. Of the 54 patients, 44 completed the trial (21 receiving synbiotics and 23 others as controls). Postoperative changes in L/M ratios and serum DAO activities were identical between the two groups. Numbers of beneficial bacteria increased in the synbiotics group after surgery but decreased in controls. Numbers of harmful microorganisms decreased in the synbiotics group but increased in controls. Total organic acid concentrations increased in the synbiotics group but decreased in controls. Incidence of infectious complications was 19% (4/21) in the synbiotics group and 52% (12/23) in controls (P<0.05). All study patients tolerated surgery (mortality 0%). Synbiotics, combined with early enteral nutrition, can reduce postoperative infections. This beneficial effect presumably involves correction of an intestinal microbial imbalance induced by surgical stress.Langenbeck s Archives of Surgery 05/2005; 390(2):104-13. · 1.81 Impact Factor -
Article: Use of 16S rRNA gene-targeted group-specific primers for real-time PCR analysis of predominant bacteria in human feces.
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ABSTRACT: 16S rRNA gene-targeted group-specific primers were designed and validated for specific detection and quantification of the Clostridium leptum subgroup and the Atopobium cluster. To monitor the predominant bacteria in human feces by real-time PCR, we used these specific primers together with four sets of group-specific primers for the Clostridium coccoides group, the Bacteroides fragilis group, Bifidobacterium, and Prevotella developed in a previous study (T. Matsuki, K. Watanabe, J. Fujimoto, Y. Miyamoto, T. Takada, K. Matsumoto, H. Oyaizu, and R. Tanaka, Appl. Environ. Microbiol. 68:5445-5451, 2002). Examination of DNA extracted from the feces of 46 healthy adults showed that the C. coccoides group was present in the greatest numbers (log10 10.3 +/- 0.3 cells per g [wet weight] [average +/- standard deviation]), followed by the C. leptum subgroup (log10 9.9 +/- 0.7 cells per g [wet weight]), the B. fragilis group (log10 9.9 +/- 0.3 cells per g [wet weight]), Bifidobacterium (log10 9.4 +/- 0.7 cells per g [wet weight]), and the Atopobium cluster (log10 9.3 +/- 0.7 cells per g [wet weight]). These five bacterial groups were detected in all 46 volunteers. Prevotella was found in only 46% of the subjects at a level of log10 9.7 +/- 0.8 cells per g (wet weight). Examination of changes in the population and the composition of the intestinal flora for six healthy adults over an 8-month period revealed that the composition of the flora of each volunteer remained stable throughout the test period.Applied and Environmental Microbiology 01/2005; 70(12):7220-8. · 3.83 Impact Factor -
Article: Experience of long-term synbiotic therapy in seven short bowel patients with refractory enterocolitis.
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ABSTRACT: Probiotic and prebiotic therapies are potent new strategies to treat various intestinal diseases, including inflammatory bowel disease and viral and bacterial infections. Synbiotics is defined as the combined use of probiotics and prebiotics and is expected to have a stronger effect on intestinal diseases than probiotics or prebiotics alone, but there has been no report of its clinical application. The authors designed a protocol for synbiotic therapy composed of Bifidobacterium breve, Lactobacillus casei, and galactooligosaccharides and preliminarily ascertained its clinical effects in humans. This protocol of synbiotic therapy was applied for more than 1 year to 7 malnourished patients with short bowels who suffered from refractory enterocolitis. The therapeutic protocol improved the intestinal bacterial flora (inducing the domination by anaerobic bacteria and suppressing the residence of pathogenic bacteria) and increased short chain fatty acids in the feces (from 27.8 to 65.09 micromol/g wet feces). All patients but 1 accelerated their body weight gain, and 5 patients showed increased serum rapid turnover proteins. This protocol for synbiotic therapy might be a potent modulator of intestinal flora and a promising strategy to treat short bowel patients with refractory enterocolitis.Journal of Pediatric Surgery 12/2004; 39(11):1686-92. · 1.45 Impact Factor -
Article: The value of bile replacement during external biliary drainage: an analysis of intestinal permeability, integrity, and microflora.
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ABSTRACT: To investigate the effect of bile replacement following percutaneous transhepatic biliary drainage, ie, external drainage, on intestinal permeability, integrity, and microflora in a clinical setting. Several authors have reported that internal biliary drainage is superior to external drainage. However, it is unclear whether bile replacement following external drainage is beneficial. Twenty-five patients with biliary cancer underwent percutaneous transhepatic biliary drainage (PTBD) as a part of presurgical management. All externally drained bile was replaced either per os or by administration through a nasoduodenal tube. The interval between PTBD and the beginning of bile replacement was 21.3 +/- 19.7 days, and the length of bile replacement was 20.7 +/- 9.6 days. The lactulose-mannitol test, measurement of serum diamine oxidase (DAO) activity, and analyses of fecal microflora and organic acids were performed before and after bile replacement. The volume of externally drained bile varied widely from patient to patient, ranging from 220 +/- 106 mL/d to 1616 +/- 394 mL/d (mean, 714 +/- 346 mL/d). Biliary concentrations of bile acids, cholesterol, and phospholipids increased significantly after bile replacement. The lactulose-mannitol (L/M) ratio decreased from 0.063 +/- 0.060 before bile replacement to 0.038 +/- 0.032 after bile replacement (P < 0.05). Serum DAO activity increased from 3.9 +/- 1.4 U/L before bile replacement to 5.1 +/- 1.6 U/L after bile replacement (P < 0.005), and the magnitude of change in serum DAO activity correlated with the length of bile replacement (r = 0.483, P < 0.05). Neither the L/M ratios nor serum DAO activities before bile replacement correlated with the interval between PTBD and the beginning of bile replacement. Fecal microflora and organic acids were unchanged. Impaired intestinal barrier function does not recover by PTBD without bile replacement. Bile replacement during external biliary drainage can restore the intestinal barrier function in patients with biliary obstruction, primarily due to repair of physical damage to the intestinal mucosa. Our results support the hypothesis that bile replacement during external drainage is beneficial.Annals of Surgery 04/2004; 239(4):510-7. · 7.49 Impact Factor -
Article: Quantitative PCR with 16S rRNA-gene-targeted species-specific primers for analysis of human intestinal bifidobacteria.
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ABSTRACT: A highly sensitive quantitative PCR detection method has been developed and applied to the distribution analysis of human intestinal bifidobacteria by combining real-time PCR with Bifidobacterium genus- and species-specific primers. Real-time PCR detection of serially diluted DNA extracted from cultured bifidobacteria was linear for cell counts ranging from 10(6) to 10 cells per PCR assay. It was also found that the method was applicable to the detection of Bifidobacterium in feces when it was present at concentrations of >10(6) cells per g of feces. Concerning the distribution of Bifidobacterium species in intestinal flora, the Bifidobacterium adolescentis group, the Bifidobacterium catenulatum group, and Bifidobacterium longum were found to be the three predominant species by examination of DNA extracted from the feces of 46 healthy adults. We also examined changes in the population and composition of Bifidobacterium species in human intestinal flora of six healthy adults over an 8-month period. The results showed that the composition of bifidobacterial flora was basically stable throughout the test period.Applied and Environmental Microbiology 02/2004; 70(1):167-73. · 3.83 Impact Factor -
Article: Clostridium difficile colonization in healthy adults: transient colonization and correlation with enterococcal colonization.
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ABSTRACT: The aim of the present study was to investigate the colonization status of Clostridium difficile in healthy individuals. In total, 139 healthy adults from two study groups were examined at intervals of 3 months. Among the 18 positive subjects, the number of subjects from whom C. difficile was isolated once, twice, three times or four times was 10 (55.6%), three (16.7%), two (11.1%) and three (16.7%), respectively. In the student group, different subjects were colonized by different PCR ribotype/PFGE types. However, the same PCR ribotype/PFGE types of C. difficile were isolated from different subjects in the employee group, indicating that cross-transmission may have occurred in this group. Continuous colonization by the same PCR ribotype/PFGE type was only observed in three subjects. C. difficile-positive subjects were significantly more densely colonized by enterococci (P<0.05) than C. difficile-negative subjects: subjects that were found to be C. difficile-positive three or four times appeared to have higher concentrations of enterococci. The present results demonstrate that, although colonization by a C. difficile strain is transient in many cases, there are healthy individuals that are colonized persistently by C. difficile. They also suggest that dense colonization of the intestine by enterococci may be associated with C. difficile colonization.Journal of Medical Microbiology 02/2004; 53(Pt 2):167-72. · 2.50 Impact Factor -
Article: Genus- and species-specific PCR primers for the detection and identification of bifidobacteria.
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ABSTRACT: 16SrDNA-targeted genus- and species-specific PCR primers have been developed and used for the identification and detection of bifidobacteria. These primers cover all of the described species that inhabit the human gut, or occur in dairy products. Identification of cultured bifidobacteria using PCR primer pairs is rapid and accurate, being based on nucleic acid sequences. Detection of bifidobacteria can be achieved using DNA extracted from human faeces as template in PCR reactions. We have found that, in adult faeces, the Bifidobacterium catenulatum group was the most commonly detected species, followed by Bifidobacterium longum, Bifidobacterium adolescentis, and Bifidobacterium bifidum. In breastfed infants, Bifidobacterium breve was the most frequently detected species, followed by Bifidobacterium infantis, B. longum and B. bifidum. It was notable that the B. catenulatum group was detected with the highest frequency in adults, although it has often been reported that B. adolescentis is the most common species. Real-time, quantitative PCR using primers targeting 16S rDNA shows promise in the enumeration of bifidobacteria in faecal samples. The approach to detect the target bacteria with quantitative PCR described in this review will contribute to future studies of the composition and dynamics of the intestinal microflora.Current issues in intestinal microbiology 10/2003; 4(2):61-9. -
Article: Development of a lethal Shiga toxin-producing Escherichia coli-infection mouse model using multiple mitomycin C treatment.
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ABSTRACT: The aim of this study was to develop a lethal Shiga toxin-producing Escherichia coli (STEC) infection model in mice. A small inoculum of 5 x 10(3) CFU of STEC strain 89020087 to mice treated with streptomycin sulfate in drinking water (5 mg/ml) lead to marked increase in the excretion of the bacteria of up to 10(9)CFU/g feces within 18 h after the challenge. Combination of administration of 5 x 10(3) CFU of STEC followed by mitomycin C (MMC) treatment during the late log phase to the early stationary phase of STEC growth in the intestine lead to fatal infection. Periodic analysis showed that there is transient but dramatic increase in the Stxs (Stx1 and Stx2) concentration in the lower intestines after multiple MMC treatment. Histopathological analysis and blood chemistry revealed damages in both kidney and hematopoietic organs but not in the brain. Comparison of the virulence of 11 different STEC strains revealed that only strains which produced high amount of Stx2 responding to MMC treatment and exerted lethal toxicity to mice, suggesting that Stx2 plays a pivotal role in the lethal infection of STEC in the mouse model.Microbial Pathogenesis 08/2003; 35(1):1-9. · 1.94 Impact Factor -
Article: Anaerobic dominant flora was reconstructed by synbiotics in an infant with MRSA enteritis.
Pediatrics International 07/2003; 45(3):359-62. · 0.63 Impact Factor -
Article: Assessment of safety of lactobacillus strains based on resistance to host innate defense mechanisms.
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ABSTRACT: Seven Lactobacillus strains belonging to four species were evaluated for pathogenicity as well as for in vitro sensitivity to the bactericidal mechanisms of macrophages in a rabbit infective endocarditis (IE) model. Two bacteremia-associated strains, L. rhamnosus PHLS A103/70 and L. casei PHLS A357/84, as well as the L. rhamnosus type strain and the probiotic L. rhamnosus strain ATCC 53103, showed moderate infectivity, and the virulence of the probiotic L. casei strain Shirota and type strains such as L. acidophilus ATCC 4356(T) and L. gasseri DSM 20243(T) in the model was negligible. The strains that showed pathogenic potential in the rabbit IE model (PHLS A357/84, PHLS A103/70, and ATCC 53103) were more resistant than strain Shirota to intracellular killing activity by mouse macrophages in vitro and also to bactericidal nitrogen intermediates, such as nitric oxide and NO(2)(-) ions. These results suggest that resistance to host innate defense systems, which would function at inflammatory lesions, should be considered in the safety assessment of Lactobacillus strains.Clinical and Diagnostic Laboratory Immunology 02/2003; 10(1):169-73. · 2.51 Impact Factor -
Article: Development of 16S rRNA-gene-targeted group-specific primers for the detection and identification of predominant bacteria in human feces.
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ABSTRACT: For the detection and identification of predominant bacteria in human feces, 16S rRNA-gene-targeted group-specific primers for the Bacteroides fragilis group, Bifidobacterium, the Clostridium coccoides group, and Prevotella were designed and evaluated. The specificity of these primers was confirmed by using DNA extracted from 90 species that are commonly found in the human intestinal microflora. The group-specific primers were then used for identification of 300 isolates from feces of six healthy volunteers. The isolates were clearly identified as 117 isolates of the B. fragilis group, 22 isolates of Bifidobacterium, 65 isolates of the C. coccoides group, and 17 isolates of Prevotella, indicating that 74% of the isolates were identified with the four pairs of primers. The remaining 79 isolates were identified by 16S ribosomal DNA sequence analysis and consisted of 40 isolates of Collinsella, 24 isolates of the Clostridium leptum subgroup, and 15 isolates of disparate clusters. In addition, qualitative detection of these bacterial groups was accomplished without cultivation by using DNA extracted from the fecal samples. The goal for this specific PCR technique is to develop a procedure for quantitative detection of these bacterial groups, and a real-time quantitative PCR for detection of Bifidobacterium is now being investigated (T. Requena, J. Burton, T. Matsuki, K. Munro, M. A. Simon, R. Tanaka, K. Watanabe, and G. W. Tannock, Appl. Environ. Microbiol. 68:2420-2427, 2002). Therefore, the approaches used to detect and identify predominant bacteria with the group-specific primers described here should contribute to future studies of the composition and dynamics of the intestinal microflora.Applied and Environmental Microbiology 12/2002; 68(11):5445-51. · 3.83 Impact Factor
Top co-authors
Top Journals
Institutions
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2003–2009
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The University of Tokyo
- Department of Pediatric Surgery
Tokyo, Tokyo-to, Japan
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2002–2009
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Yakult Central Institute for Microbiological Research
Musashino, Tokyo-to, Japan
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2004
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Tokyo Medical University
Tokyo, Tokyo-to, Japan
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