Maria Luisa Callegari
Catholic University of the Sacred Heart
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Maria Luisa Callegari.
Applied and Environmental Microbiology | 2005
Paola Lavermicocca; Francesca Valerio; Stella Lisa Lonigro; Maria De Angelis; Lorenzo Morelli; Maria Luisa Callegari; Carlo Giuseppe Rizzello; Angelo Visconti
ABSTRACT With the aim of developing new functional foods, a traditional product, the table olive, was used as a vehicle for incorporating probiotic bacterial species. Survival on table olives of Lactobacillus rhamnosus (three strains), Lactobacillus paracasei (two strains), Bifidobacterium bifidum (one strain), and Bifidobacterium longum (one strain) at room temperature was investigated. The results obtained using a selected olive sample demonstrated that bifidobacteria and one strain of L. rhamnosus (Lactobacillus GG) showed a good survival rate, with a recovery of about 106 CFU g−1 after 30 days. The Lactobacillus GG population remained unvaried until the end of the experiment, while a slight decline (to about 105 CFU g−1) was observed for bifidobacteria. High viability, with more than 107 CFU g−1, was observed throughout the 3-month experiment for L. paracasei IMPC2.1. This strain, selected for its potential probiotic characteristics and for its lengthy survival on olives, was used to validate table olives as a carrier for transporting bacterial cells into the human gastrointestinal tract. L. paracasei IMPC2.1 was recovered from fecal samples in four out of five volunteers fed 10 to 15 olives per day carrying about 109 to 1010 viable cells for 10 days.
Applied and Environmental Microbiology | 2006
Marina Elli; Maria Luisa Callegari; Susanna Ferrari; Elena Bessi; Daniela Cattivelli; Sara Soldi; Lorenzo Morelli; Nathalie Goupil Feuillerat; Jean-Michel Antoine
ABSTRACT Whether Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus can be recovered after passage through the human gut was tested by feeding 20 healthy volunteers commercial yogurt. Yogurt bacteria were found in human feces, suggesting that they can survive transit in the gastrointestinal tract.
PLOS ONE | 2014
Eugenia Bruzzese; Maria Luisa Callegari; Valeria Raia; Sara Viscovo; Riccardo Scotto; Susanna Ferrari; Lorenzo Morelli; Vittoria Buccigrossi; Andrea Lo Vecchio; Eliana Ruberto; Alfredo Guarino
Background & Aims Intestinal inflammation is a hallmark of cystic fibrosis (CF). Administration of probiotics can reduce intestinal inflammation and the incidence of pulmonary exacerbations. We investigated the composition of intestinal microbiota in children with CF and analyzed its relationship with intestinal inflammation. We also investigated the microflora structure before and after Lactobacillus GG (LGG) administration in children with CF with and without antibiotic treatment. Methods The intestinal microbiota were analyzed by denaturing gradient gel electrophoresis (DGGE), real-time polymerase chain reaction (RT-PCR), and fluorescence in situ hybridization (FISH). Intestinal inflammation was assessed by measuring fecal calprotectin (CLP) and rectal nitric oxide (rNO) production in children with CF as compared with healthy controls. We then carried out a small double-blind randomized clinical trial with LGG. Results Twenty-two children with CF children were enrolled in the study (median age, 7 years; range, 2–9 years). Fecal CLP and rNO levels were higher in children with CF than in healthy controls (184±146 µg/g vs. 52±46 µg/g; 18±15 vs. 2.6±1.2 µmol/L NO2 −, respectively; P<0.01). Compared with healthy controls, children with CF had significantly different intestinal microbial core structures. The levels of Eubacterium rectale, Bacteroides uniformis, Bacteroides vulgatus, Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Faecalibacterium prausnitzii were reduced in children with CF. A similar but more extreme pattern was observed in children with CF who were taking antibiotics. LGG administration reduced fecal CLP and partially restored intestinal microbiota. There was a significant correlation between reduced microbial richness and intestinal inflammation. Conclusions CF causes qualitative and quantitative changes in intestinal microbiota, which may represent a novel therapeutic target in the treatment of CF. Administration of probiotics restored gut microbiota, supporting the efficacy of probiotics in reducing intestinal inflammation and pulmonary exacerbations. Trial Registration ClinicalTrials.gov NCT 01961661
Allergy | 2015
Gian Vincenzo Zuccotti; Fabio Meneghin; Arianna Aceti; Giovanni Barone; Maria Luisa Callegari; A Di Mauro; Mp Fantini; Davide Gori; Flavia Indrio; Luca Maggio; Lorenzo Morelli; Luigi Corvaglia
Growing evidence underlines the pivotal role of infant gut colonization in the development of the immune system. The possibility to modify gut colonization through probiotic supplementation in childhood might prevent atopic diseases. The aim of the present systematic review and meta‐analysis was to evaluate the effect of probiotic supplementation during pregnancy and early infancy in preventing atopic diseases. PubMed, Embase and Cochrane Library were searched for randomized controlled trials evaluating the use of probiotics during pregnancy or early infancy for prevention of allergic diseases. Fixed‐effect models were used, and random‐effects models where significant heterogeneity was present. Results were expressed as risk ratio (RR) with 95% confidence interval (CI). Seventeen studies, reporting data from 4755 children (2381 in the probiotic group and 2374 in the control group), were included in the meta‐analysis. Infants treated with probiotics had a significantly lower RR for eczema compared to controls (RR 0.78 [95% CI: 0.69–0.89], P = 0.0003), especially those supplemented with a mixture of probiotics (RR 0.54 [95% CI: 0.43–0.68], P < 0.00001). No significant difference in terms of prevention of asthma (RR 0.99 [95% CI: 0.77–1.27], P = 0.95), wheezing (RR 1.02 [95% CI: 0.89–1.17], P = 0.76) or rhinoconjunctivitis (RR 0.91 [95% CI: 0.67–1.23], P = 0.53) was documented. The results of the present meta‐analysis show that probiotic supplementation prevents infantile eczema, thus suggesting a new potential indication for probiotic use in pregnancy and infancy.
Microbiology | 1998
Maria Luisa Callegari; B. Riboli; Jan-Willem Sanders; Pier Sandro Cocconcelli; Jan Kok; G Venema; Lorenzo Morelli
Lactobacillus helveticus CNRZ 892 contains a surface layer (S-layer) composed of protein monomers of 43 kDa organized in regular arrays. The gene encoding this protein (slpH) has been cloned in Escherichia coli and sequenced. slpH consists of 440 codons and is preceded by a ribosome-binding site (RBS) and followed by a putative rho-independent terminator. Indeed, Northern analysis revealed that slpH is a monocistronic gene. The gene is preceded by a possible promotor of which the -35 and -10 hexanucleotides are separated by 17 nt. By primer extension analysis the transcription start site was mapped at 7 nt downstream of the -10 sequence while the deduced amino acid sequence of SlpH shows a leader peptide of 30 aa. The slpH gene has been amplified by PCR and the fragment, carrying the complete gene from the RBS to the stop codon, has been cloned in a lactococcal gene expression vector downstream of promoter P32. Lactococcus lactis MG1363 carrying the resulting plasmid produced and secreted an S-layer monomer with the same molecular mass as the authentic L. helveticus CNRZ 892 SlpH, as judged by SDS-PAGE. Immunoelectron microscopy revealed that SlpH was bound to the lactococcal cell walls in small clumps and accumulated in the growth medium as small sheets.
Nutrition Journal | 2003
Lorenzo Morelli; Daniela Zonenschain; Maria Luisa Callegari; Enzo Grossi; Federico Maisano; Michele Fusillo
BackgroundUse of synbiotic preparations as dietary supplement is believed to be a valid approach to restore and maintain colonic microflora. However, only few papers have been published on the assessment of these food supplements and none of them have used molecular biology techniques to evaluate the effects of the probiotic components.MethodsTwelve healthy volunteers were recruited. Faecal samples were taken before and at various time points during the administration period and at day 3 in the post-treatment period. Stool culture were performed and amplified ribosomal DNA restriction analysis was used to detect L. paracasei, the major bacterial component of the synbiotic products.ResultsAn increase of at least 1 log of L. paracasei-like bacteria was observed in all subjects. An increase of as much as 3 log was seen in subjects who had a low number of L. paracasei-like lactobacilli at the baseline. The counts of L. paracasei-like lactobacilli were found to persist for at least 3 days after discontinuation of intake in healthy volunteers in 7 subjects. Genetic analysis showed that the maiority of vancomicin insensitive lactobacilli were real L. paracasei, as the strains administered with the tested product.ConclusionThis study has shown that the strains of L paracasei administered with a synbiotic dietary supplement are able to survive through the gastrointestinal tract and to persist for at least a few days. It was also shown the efficacy of a synbiotic preparation to positively affect the microflora of healthy volunteers.
Systematic and Applied Microbiology | 2000
Marco Ventura; Ivan A. Casas; Lorenzo Morelli; Maria Luisa Callegari
Amplified ribosomal DNA restriction analysis (ARDRA) was used to identify different species of Lactobacillus isolated from human faeces and vagina. PCR-ARDRA was performed using a set of four restriction enzymes, able to differentiate fourteen species of Lactobacillus. The PCR-ARDRA procedure described in this paper was shown to be a reliable and rapid method for identifying Lactobacillus species from intestinal and vaginal microflora at species and subspecies level.
Journal of Medical Microbiology | 2008
Gaetano Iapichino; Maria Luisa Callegari; Silvia Marzorati; M. Cigada; Davide Corbella; Susanna Ferrari; Lorenzo Morelli
We evaluated the relationship between the intestinal microbiota composition and clinical outcome in a group of 15 high-risk patients admitted for acute infection and/or surgical/accidental trauma who were treated with systemic antibiotics according to standard intensive care unit (ICU) protocols. There was a high mortality rate amongst these patients, each of whom had a considerable organ failure score at admission, respiratory assistance during the most of their ICU stay and a long length of stay. All of these individuals received sedation and enteral nutrition, and the majority also received insulin, vasoactive drugs and some stress-ulcer prophylaxis agents. The intestinal microbiota composition was assessed using denaturing gradient gel electrophoresis (DGGE), a molecular biology tool used to characterize bacterial ecosystems. As all of the patient subjects were in good health prior to their acute illness and admission to the ICU, the first faecal samples obtained from this group showed a DGGE banding pattern that was similar to that of healthy subjects. After 1 week of critical illness, coupled with intensive care treatment, including antibiotics, a very definite alteration in the overall microbiota composition was evident, as revealed by a reduction in the number of DGGE bands. Further pronounced changes to the DGGE banding profiles could be observed in patients remaining in the ICU for 2 weeks. Moreover, a dominant band, identified by sequencing as highly related to Enterococcus, was detected in the DGGE profile of some of our patient subjects. We also performed real-time PCR and obtained results that were in agreement with our qualitative evaluations using DGGE. The degree of organ failure and ICU mortality was significantly higher in patients for whom a high reduction in microbiota biodiversity was coupled with a massive presence of enterococci. A statistically significant link between these two ecological traits and the use of clindamycin was also found.
International Journal of Food Sciences and Nutrition | 2012
Luca Calani; Daniele Del Rio; Maria Luisa Callegari; Lorenzo Morelli; Furio Brighenti
Green tea is a popular beverage, prepared with infusion of unfermented dried leaves of Camellia sinensis, and is one of the most relevant sources of polyphenolic compounds in the human diet. This study reports green tea flavan-3-ol absorption, metabolism and complete urinary excretion up to 48 h in 20 healthy volunteers. Urinary and tea samples were analysed by high-performance liquid chromatography coupled with tandem mass spectrometry. Green tea contained monomeric flavan-3-ols and proanthocyanidins with a total polyphenol content of 728 μmol. A total of 41 metabolites were identified in urines, all present in conjugated forms. Among these, six colonic metabolites of green tea flavan-3-ols were identified for the first time after green tea consumption in humans. The average 48 h bioavailability was close to 62%, major contributors being microbial metabolites. Some volunteer showed a 100% absorption/excretion, whereas some others were unable to efficiently absorb/excrete this class of flavonoids. This suggests that colonic ring fission metabolism could be relevant in the putative bioactivity of green tea polyphenols.
Liver International | 2013
Giuseppe D'Argenio; Rita Cariello; Concetta Tuccillo; Giovanna Mazzone; Alessandro Federico; A. Funaro; Laura de Magistris; Enzo Grossi; Maria Luisa Callegari; Marilena Chirico; N. Caporaso; Marco Romano; Lorenzo Morelli; Carmela Loguercio
Evidence indicates that intestinal microbiota may participate in both the induction and the progression of liver damage. The aim of our research was the detection and evaluation of the effects of chronic treatment with a symbiotic formulation on CCl4‐induced rat liver fibrosis.