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Tagliabue A.,University of Pavia | Elli M.,AAT Advanced Analytical Technologies Srl
Nutrition, Metabolism and Cardiovascular Diseases

Aims: In recent years, gut microbiota have gained a growing interest as an environmental factor that may affect the predisposition toward adiposity. In this review, we describe and discuss the research that has focused on the involvement of gut microbiota in human obesity. We also summarize the current knowledge concerning the health effects of the composition of gut microbiota, acquired using the most recent methodological approaches, and the potential influence of gut microbiota on adiposity, as revealed by animal studies. Data synthesis: Original research studies that were published in English or French until December 2011 were selected through a computer-assisted literature search. The studies conducted to date show that there are differences in the gut microbiota between obese and normal-weight experimental animals. There is also evidence that a high-fat diet may induce changes in gut microbiota in animal models regardless of the presence of obesity. In humans, obesity has been associated with reduced bacterial diversity and an altered representation of bacterial species, but the identified differences are not homogeneous among the studies. Conclusions: The question remains as to whether changes in the intestinal microbial community are one of the environmental causes of overweight and obesity or if they are a consequence of obesity, specifically of the unbalanced diet that often accompanies the development of excess weight gain. In the future, larger studies on the potential role of intestinal microbiota in human obesity should be conducted at the species level using standardized analytical techniques and taking all of the possible confounding variables into account. © 2012 Elsevier B.V. Source

Biasucci G.,Guglielmo da Saliceto Hospital | Rubini M.,Guglielmo da Saliceto Hospital | Riboni S.,Guglielmo da Saliceto Hospital | Morelli L.,Catholic University of the Sacred Heart | And 2 more authors.
Early Human Development

The first colonisation of the intestine is one of the most profound immunological exposures faced by the newborn and it is influenced by external and internal factors. The early composition of human microbiota could have long-lasting metabolic effects and the initial composition of human intestinal bacteria is also known to affect postnatal immune system development, as we are already aware that reduced microbial stimulation during infancy would result in slower postnatal maturation of the immune system and development of an optimal balance between TH1 and TH2-like immunity. Mode of delivery has a major role on the composition of intestinal microbiota in early infancy, as it has been shown that infants born by Caesarean section (CS) have lower numbers of Bifidobacteria and Bacteroides compared with vaginally born infants.We designed a study to investigate the influence of mode of delivery (CS vs. vaginal delivery) on intestinal microbial composition on day 3 of life using PCR-denaturing gradient gel electrophoresis (DGGE) and PCR-temperature gradient gel electrophoresis (TGGE). Both DGGE and TGGE analyses have been used, together with the specific amplifications for 10 Bifidobacterium sp., 3 Ruminococcus sp., and Bacteroides that all have a highly relevant physiological role in the intestinal ecosystem of the newborn.A total of 46 term infants were enrolled in the study, consecutively recruiting all the CS-delivered babies (n = 23; 8 males and 15 females) and the immediately following spontaneously delivered babies (n = 23; 11 males and 12 females). DGGE analysis carried out with Bifidobacterium-specific primers revealed the presence of this genus in 13 of 23 (56.5%) samples derived from vaginally delivered newborns but in none of the samples obtained from newborns delivered by CS. PCR analysis with Bifidobacterium-species-specific primers showed that naturally delivered infants had a large number of bifidobacterial species, whereas in CS-delivered babies only two samples (8.7%) gave positive results, one for B. longum and another for B. gallicum. In all babies enrolled, micro-organisms belonging to Ruminococcus species were absent and Bacteroides was found in 8.7% of spontaneously delivered babies only.Based on our findings, it seems that newborn's intestinal bacteria during the first 3. days of life are strongly influenced by mode of delivery. The intestinal flora of CS and vaginally delivered infants appears to be very different; the former being altered and characterised by a substantial absence of Bifidobacteria sp., the latter characterised by subject-specific microbial profiles, although predominant groups such as B. longum and B. catenulatum could be identified.In summary, mode of delivery does affect the early stage of intestinal bacterial colonisation, which is altered in CS-delivered infants compared with vaginally delivered infants, with only a minor influence of the type of feeding. In addition, the importance of methodological aspects for determining intestinal microbiota in clinical trials requires emphasis if intestinal microbiota composition is to be considered a measure of postnatal adaptation. © 2010 Elsevier Ltd. Source

Giovannini M.,University of Milan | Verduci E.,University of Milan | Gregori D.,University of Milan | Ballali S.,University of Padua | And 3 more authors.
Journal of the American College of Nutrition

Objective: The objective of the study was to investigate the effects of a galacto-oligosaccharides (GOS)-supplemented formula on the intestinal microbiota in healthy term infants, with a specific consideration for gastrointestinal symptoms as colic, stool frequency and consistency, regurgitation.Methods: This was a randomized, double-blind, controlled, parallel-group clinical trial performed simultaneously by 6 centers in Italy. Three groups were considered: breastfed, formula-fed, and GOS-supplemented formula-fed infants. Formula-fed infants were randomized to receive either the control or the study formula and consume the assigned formula exclusively until the introduction of complementary feeding. The nutritional composition of the 2 formulas were identical, apart from the supplemented GOS (0.4 g/100 mL) in the study formula. Four different types of bacteria were evaluated in order to assess the efficacy of GOS-supplemented formula on infants: Bifidobacterium, Lactobacillus, and Clostridium, Escherichia coli.Results: A total of 199 breastfed infants and 163 formula-fed infants were recruited. When considering stool frequency and consistency, GOS-supplemented formula presented normal and soft stools in the majority of episodes (89%). In the supplemented group the incidence of colic was lower with respect to the control group. A significantly lower count of Clostridium and a higher count of Bifidobacterium were found when comparing study formula and control formula in infants with colic. In children with colic the ratio between Clostridium count and Bifidobacterium and Lactobacillus count was in favor of the latter two when considering the GOS-supplemented formula group with respect to the control one.Conclusions: The prebiotic-supplemented formula mimicked the effect of human milk in promoting Bifidobacterium and Lactobacillus growth and in inhibiting Clostridium growth, resulting in a significantly lower presence of colic. © 2014, © American College of Nutrition Published by Taylor & Francis Group, LLC. Source

Kalkanci A.,Gazi University | Elli M.,AAT Advanced Analytical Technologies Srl | Adil Fouad A.,Gazi University | Yesilyurt E.,Gazi University | Jabban Khalil I.,Gazi University
Journal de Mycologie Medicale

Objectives: The aim of this study was to determine the susceptibility of 77 mould strains: Aspergillus fumigatus (20)., Aspergillus flavus (8), Aspergillus niger (4), Aspergillus ochraceus (2), Penicillium citrinum (15), Penicillium crysogenum (14), Penicillium aurantiogriseum (1), Penicillium roquefortii (4), Penicillium paneum (2), Rhizopus spp. (3), Tricoderma spp. (1) and Mucor spp. (3) to biocides. Methods: MIC determination was determined based on CLSI methodology. Results: For hospital acquired strains, MIC50 was 0.5mg/L, MIC90 was 1mg/L for chlorhexidine (CHX); MIC50 was 0.5mg/L, and MIC90 was 1mg/L for benzalkonium chloride (BZC); MIC50 was 1mg/L, and MIC90 was 2mg/L for triclosan (TRC); MIC50 was 1024mg/L, and MIC90 was 2048mg/L for sodium hypochloride (SHC). For feed and food isolates MIC50 was 2mg/L, MIC90 was 8mg/L for CHX, MIC50 was 2mg/L, and MIC90 was 4mg/L for BZC, MIC50 was 2mg/L, and MIC90 was 4mg/L for TRC, MIC50 was 256mg/L, and MIC90 was 512mg/L for SHC. Conclusion: We can conclude that food isolates presented slightly higher MIC50 and MIC90 values for CHX, BNZ and TRC, but not for SHC. © 2015 Elsevier Masson SAS. Source

Elli M.,AAT Advanced Analytical Technologies Srl | Arioli S.,University of Milan | Guglielmetti S.,University of Milan | Mora D.,University of Milan
Journal of Global Antimicrobial Resistance

Disinfectants have been used in a variety of environmental applications, in products for personal care and in the food industry. The food industry has increased the use of biocides and chemical-based disinfectants to control microbial ecology at production sites in an effort to improve hygiene measures and food safety. However, the susceptibility profile of micro-organisms to disinfectants has been largely neglected. This study therefore aimed to provide this type of information by focusing on the four most commonly used biocides in the food industry, determining their minimum inhibitory concentrations (MICs) and analysing the distribution of MICs across a variety of micro-organisms. In total, 99 different strains of Bifidobacterium spp. were studied. Results showed a unimodal distribution of MICs for chlorhexidine, triclosan (Irgasan) and sodium hypochlorite with no apparent species-specific correlation. Conversely, part of the tested bifidobacteria population (20%) showed reduced susceptibility to benzalkonium chloride compared with the susceptibility exhibited by the majority of the tested bacterial community. The highest MICs were distributed among almost all of the considered Bifidobacterium spp. In generally, the sensitivity of the studied strains to the four tested biocides appeared to be a genus-related trait. © 2013 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved. Source

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