Faecal bifidobacteria in Indian neonates & the effect of asymptomatic rotavirus infection during the first month of life

Background & objectives: Bifidobacteria colonize the gut after the first week of life and remain an important component of the gut microbiota in infancy. This study was carried out to characterize the diversity and number of bifidobacteria colonizing the gut in Indian neonates and to investigate whether asymptomatic infection with rotavirus in the first month of life affected gut colonization by bidifobacteria. Methods: DNA was isolated from faeces of 14 term-born neonates who were under surveillance for rotavirus infection. Bacterial and bifidobacterial diversity was evaluated by temporal temperature gradient electrophoresis (TTGE) of 16S rDNA amplified using total bacteria and bifidobacteria-specific primers. Real time PCR, targeting 16S rDNA, was used to quantitate faecal bifidobacteria and enterobacteria. Results: TTGE of conserved bacterial 16S rDNA showed 3 dominant bands of which Escherichia coli (family Enterobacteriaceae) and Bifidobacterium (family Bifidobacteriaceae) were constant. TTGE of Bifidobacterium genus-specific DNA showed a single band in all neonates identified by sequencing as Bifidobacterium longum subsp. infantis. Faecal bifidobacterial counts (log10 cfu/g faeces) ranged from 6.1 to 9.3 and enterobacterial counts from 6.3 to 9.5. Neonates without and with rotavirus infection in the first week of life did not show significant differences in the median count of bifidobacteria (log10 count 7.48 vs. 7.41) or enterobacteria (log10 count 8.79 vs. 7.92). Interpretation amp; conclusions: B. longum subsp. infantis was the sole bifidobacterial species colonizing the gut of Indian neonates. Asymptomatic rotavirus infection in the first month of life was not associated with alteration in faecal bifidobacteria or enterobacteria

Paniculitis mesentérica asociada al uso de bifosfonatos: ¿son estos más proinflamatorios de lo que sabemos?

La paniculitis mesentérica se caracterizada por una inflamación crónica inespecífica del tejido adiposo del mesenterio intestinal, y su etiología es desconocida. Se ha relacionado con malignidad, vasculitis, enfermedades reumáticas y con determinados fármacos. Presentamos un caso de paniculitis mesentérica asociada a la toma de bifosfonatos, no descrita previamente en la literatura, apoyando así el concepto de sus potenciales efectos secundarios proinflamatorios.Mesenteric panniculitis is characterized by chronic inflammation of the adipose tissue of the intestinal mesentery, and its etiology is unknown. It has been associated with malignancy, vasculitis, rheumatic diseases and the use of certain drugs. We present a case of panniculitis associated with bisphosphonate use, not previously described in the literature, thus suggesting its potential secondary proinflammatory effect

Amoxicillin treatment modifies the composition of Bifidobacterium species in infant intestinal microbiota

Objectives: Amoxicillin is a beta-lactam antibiotic largely used in childhood. However only few studies described its impact on composition of children gut microbiota, in particular on Bifidobacterium populations considered as beneficial microorganisms. In this study, the impact on faecal Bifidobacterium species of a seven-day amoxicillin treatment was quantitatively and qualitatively assessed in infants during an episode of acute respiratory infection. Methods: Faecal samples from 31 infants were obtained on day 0 (just before amoxicillin therapy) and on day 7 (the end of therapy). Total DNA was extracted and bifidobacteria were quantified using real-time PCR. Predominant Bifidobacterium species were then identified using specific PCR-TTGE. Results: Bifidobacteria concentrations were not significantly altered by amoxicillin compared to the healthy group. However, amoxicillin treatment induced a complete disappearance of Bifidobacterium adolescentis species (occurrence rate of 0% versus 36.4% in healthy group, P < 0.001), a significant decrease in the occurrence rate of Bifidobacterium bifidum (23% versus 54.5% in healthy group, P < 0.05), but did not affect Bifidobacterium longum (93.5% versus 100% in healthy group) and Bifidobacterium pseudocatenulatum/B. catenulatum (about 55% in both groups). The number of Bifidobacterium species per microbiota significantly decreased from 2.5 1 for healthy group to 1.8 0.9 for treated infants (P < 0.05). Conclusions: This study showed that a 7 day amoxicillin treatment did not alter the counts of Bifidobacterium. However amoxicillin can have an impact by changing the microbiota at the species level and decreased the diversity of this population.This work was supported by Ecos (grant number C01S03)

Long-term changes in human colonic Bifidobacterium populations induced by a 5-day oral amoxicillin-clavulanic acid treatment.

International audienceThe objective of this study was to assess the possible modifications due to amoxicillin-clavulanic acid (AMC) treatment on total bacteria and on Bifidobacterium species balance in human colonic microbiota. Eighteen healthy volunteers (19 to 36 years old) were given a 875/125 mg dose of AMC twice a day for 5 days. Fecal samples were obtained before and after antibiotic exposure. After total DNA extraction, total bacteria and bifidobacteria were specifically quantified using real-time PCR. Dominant species were monitored over time using bacterial and bifidobacterial Temporal Temperature Gradient gel Electrophoresis (TTGE). At the end of AMC exposure, total bacterial concentrations as well as bifidobacteria concentrations were significantly reduced compared to before AMC exposure:10.7±0.1 log(10) 16S rRNA gene copies/g vs 11.1±0.1 log(10) (p = 0.003) and 8.1±0.5 log(10) 16S rRNA gene copies/g vs 9.4±0.3 log(10) (p = 0.003), respectively. At the same time, the mean similarity percentages of TTGE bacteria and TTGE bifidobacteria profiles were significantly reduced compared to before AMC exposure: 51.6%±3.5% vs 81.4%±2.1% and 55.8%±7.6% vs 84.5%±4.1%, respectively. Occurrence of B. adolescentis, B. bifidum and B. pseudocatenulatum/B. catenulatum species significantly decreased. Occurrence of B. longum remained stable. Moreover, the number of distinct Bifidobacterium species per sample significantly decreased (1.5±0.3 vs 2.3±0.3; p = 0.01). Two months after AMC exposure, the mean similarity percentage of TTGE profiles was 55.6% for bacteria and 62.3% for bifidobacteria. These results clearly demonstrated that a common antibiotic treatment may qualitatively alter the colonic microbiota. Such modifications may have potential long-term physiological consequences

Differential Effects of Bifidobacterium pseudolongum Strain Patronus and Metronidazole in the Rat Gut▿

In the luminal contents of metronidazole-treated rats, there was a dominant Bifidobacterium species. A strain has been isolated, its 16S rRNA gene has been sequenced, and the strain has been named Bifidobacterium pseudolongum strain Patronus. In this study, using an experimental model of healthy rats, the effects of metronidazole treatment and B. pseudolongum strain Patronus administration on the luminal and mucosa-associated microbiota and on gut oxidation processes were investigated. Metronidazole treatment and the daily gavage of rats with B. pseudolongum strain Patronus increased the numbers of bifidobacteria in cecal contents and in cecal mucosa-associated microbiota compared with those in control rats. Metronidazole reduced the colonic oxidative damage to proteins. This is the first evidence that B. pseudolongum strain Patronus exerts an effect on a biomarker of oxidative damage by reducing the susceptibility to oxidation of proteins in the colon and the small bowel. Antioxidant effects of metronidazole could be linked to the bifidobacterial increase but also to other bacterial modifications

Teroristični napad v Beslanu

International audienc

Oral administration of viable Bifidobacterium pseudolongum strain Patronus modified colonic microbiota and increased mucus layer thickness in rat

International audienc

Mean similarity coefficients of specific <i>Bifidobacterium</i> TTGE profiles of samples collected before and after AMC exposure (day0–day5) and calculated according to the reference period (day-12 day-6 day 0; n = 17).

<p>Mean similarity coefficients of specific <i>Bifidobacterium</i> TTGE profiles of samples collected before and after AMC exposure (day0–day5) and calculated according to the reference period (day-12 day-6 day 0; n = 17).</p