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M De Angelis

Publications and source records attributed to M De Angelis.

At least 19 recordsLinked to original sources
PubMed2007

Molecular and functional characterization of Lactobacillus sanfranciscensis strains isolated from sourdoughs.

Fifty isolates of Lactobacillus sanfranciscensis from Italian sourdoughs were identified and typed by a polyphasic approach which included genotypic and phenotypic criteria. Genotypic diversity was characterized by Ribosomal Intergenic Spacer Analysis (RISA) of PCR amplified 16S-23S rDNA spacer region, denaturing gradient gel electrophoresis (DGGE) of PCR amplified rpoB (beta subunit of RNA polymerase) gene, and rep-PCR (PCR amplification of repetitive bacterial DNA elements) analyses. The RISA analysis produced a unique electrophoretical profile of four bands (ranging from 300 to 600 bp) for all L. sanfranciscensis isolates. The DGGE analysis of rpoB gene allowed the subdivision of isolates in four clusters. The resolution found by using rep-PCR with primers BOXA1R and REP1R-I/REP2-I allowed the widening of the level of isolates heterogeneity. Phenotypic diversity was evaluated by Biolog System and characterization of several technological traits (e.g., acidification kinetics, proteinase and peptidase activities). L. sanfranciscensis isolates used a large varieties of carbon sources such as dextrin, D-fructose, L-fucose, alpha-D-glucose, maltose, palatinose, L-rhanmose, L- and D,L-lactic acids and L-methionine. The acidification activity and related quotient of fermentation, and the peptidase (PepN, PepV, PepT, PepI, PepX, PepQ and PepR) activities markedly varied among strains. The same was found concerning the capacity to liberate amino acids during sourdough fermentation. This study could be considered as an example of a computerized analysis of the genotypic and phenotypic traits to reliably and rapidly differentiate sourdough isolates. Although some L. sanfranciscensis isolates combined several technological traits, the association of more selected strains seemed to be a requisite to get optimal sourdough characteristics.

Bread↗
PubMed2006

Defined multi-species semi-liquid ready-to-use sourdough starter.

This paper aimed at setting up a protocol for the manufacture of a defined multi-species semi-liquid ready-to-use sourdough starter consisting of lactic acid bacteria (LAB) selected on the basis of their capacity of rapid acidification and adaptation to several technological factors. Preliminarily, 56 strains of sourdough LAB were screened based on the acidification kinetics during sourdough fermentation. The influence of temperature (25-37 degrees C), NaCl (2%, w/w, of wheat flour), initial cell number (10(7)-10(9) cfu g(-1)), dough yield (150-180), substrate for cell cultivation (mMRS or SDB media) and phase of cell growth (exponential or stationary phases) on the kinetics of acidification was also determined. Lactobacillus casei DPPMA27, Weissella confusa DPPMA20 and Lactobacillus fructivorans DPPMA8 were selected and used to produce a defined multi-species semi-liquid sourdough starter. Fermentation was carried out in a 2l batch fermentation bioreactor (12 h at 37 degrees C), under controlled pH, by cultivating cells in a medium made of water (60%), flour and other nutrients (40%). The semi-liquid sourdough starter was stored for 30 days under different conditions and used for dough fermentation (dough yield 160). The microbial composition, acidifying activity and fermentation end-products were kept constant during 21 days of storage. The findings of this study may be useful to increase the use of sourdough in bakery industries.

Bioreactors↗
PubMed2006

Dorsal buccal mucosa graft urethroplasty for female urethral strictures.

PURPOSE: We describe the feasibility and complications of dorsal buccal mucosa graft urethroplasty in female patients with urethral stenosis. MATERIALS AND METHODS: From April 2005 to July 2005, 3 women 45 to 65 years old (average age 53.7) with urethral stricture disease underwent urethral reconstruction using a dorsal buccal mucosa graft. Stricture etiology was unknown in 1 patient, ischemic in 1 and iatrogenic in 1. Buccal mucosa graft length was 5 to 6 cm and width was 2 to 3 cm. The urethra was freed dorsally until the bladder neck and then opened on the roof. The buccal mucosa patch was sutured to the margins of the opened urethra and the new roof of the augmented urethra was quilted to the clitoris corpora. RESULTS: In all cases voiding urethrogram after catheter removal showed a good urethral shape with absent urinary leakage. No urinary incontinence was evident postoperatively. On urodynamic investigation all patients showed an unobstructed Blaivas-Groutz nomogram. Two patients complained about irritative voiding symptoms at catheter removal, which subsided completely and spontaneously after a week. CONCLUSIONS: The dorsal approach with buccal mucosa graft allowed us to reconstruct an adequate urethra in females, decreasing the risks of incontinence and fistula.

Aged↗
PubMed2006

Characterization of the Enterobacteriaceae isolated from an artisanal Italian ewe's cheese (Pecorino Abruzzese).

AIMS: To evaluate some physiological characteristics of the Enterobacteriaceae isolated from Pecorino cheese. METHODS AND RESULTS: The production of organic acids, secondary volatile compounds, biogenic amines (BA) and the lipolytic and proteolytic activities of Citrobacter braakii, Enterobacter sakazakii, Escherichia coli, Kluyvera spp., Salmonella enterica ssp. arizonae and Serratia odorifera strains were determined in skim milk after 48 h of fermentation at 30 degrees C. The proteolytic activity observed only in Ser. odorifera and Kluyvera spp. was confirmed by the peptide profiles of the pH 4.6-insoluble fraction using RP-HPLC; however, the lipase activity was evidenced in all the isolates of E. coli, Kluyvera spp. and Salm. enterica ssp. arizonae. During fermentation, all the strains utilized citric acid and produced significant quantities of putrescine followed by histamine, spermine and spermidine as well as acetic and lactic acid. Moreover, the major volatile compounds produced were ethanol, 2,3-butanedione, 3-hydroxy-2-butanone, 2-heptanone and acetone. CONCLUSIONS: The Enterobacteriaceae of dairy origin possess many metabolic activities that could affect the sensory quality of the cheese in which they grow during ripening. SIGNIFICANCE AND IMPACT OF THE STUDY: The important physiological characteristics possessed by Enterobacteriaceae confirm the complexity of the microbiota of Pecorino Abruzzese cheese, which influences the typical sensory properties of this product.

Acetic Acid↗
PubMed2006

Comparison of the compositional, microbiological, biochemical, and volatile profile characteristics of nine Italian ewes' milk cheeses.

Nine Italian ewes' milk cheeses were compared for compositional, microbiological, biochemical, and volatile profile characteristics. Mean values for the gross composition were rather similar among cheeses. The lowest pH values were found for cheeses that used primary starters. At the end of ripening, cheeses made from raw milk contained >6.0 log10 cfu/g of nonstarter lactic acid bacteria. Several species of lactobacilli were identified, but Lactobacillus plantarum and Lactobacillus paracasei were dominant. Random amplified polymorphic DNA-PCR analysis showed the biodiversity among the strains, and in several cases a relationship with the cheese of provenance. Cheeses differed mainly for secondary proteolysis, as shown by the principal component analysis applied to reversed-phase fast protein liquid chromatography data of the pH 4.6-soluble fractions and by determination of the free AA. A total of 113 volatile components were identified in the Italian Pecorino cheeses by solid-phase microextraction coupled with gas chromatography-mass spectrometry analysis. The volatile profiles of the 9 cheeses differed significantly. Quantitatively, alcohols were the most abundant chemical class for some cheeses, whereas ketones were the most abundant for other cheeses. Esters and carboxylic acids were largely found. Specific volatile components seemed to distinguish specific cheeses.

Amino Acids↗
PubMed2005

Proteolytic activity and reduction of gliadin-like fractions by sourdough lactobacilli.

AIMS: To characterize the peptide hydrolase system of Lactobacillus plantarum CRL 759 and CRL 778 and evaluate their proteolytic activity in reducing gliadin-like fractions. METHODS AND RESULTS: The intracellular peptide hydrolase system of Lact. plantarum CRL 759 and CRL 778 involves amino-, di- (DP), tri- (TP) and endopeptidase activities. These peptidases are metalloenzymes inhibited by EDTA and 1,10-phenanthroline and stimulated by Co2+. DP and TP activities of Lact. plantarum CRL 759 and CRL 778, respectively, were completely inhibited by Cu2+. Lactobacillus plantarum CRL 778 showed the highest proteolytic activity and amino acids release in fermented dough. The synthetic 31-43 alpha-gliadin fragment was hydrolysed to 36% and 73% by Lact. plantarum CRL 778 and CRL 759 respectively. CONCLUSIONS: Lactobacillus plantarum CRL 759 and CRL 778 have an active proteolytic system, which is responsible for the high amino acid release during sourdough fermentation and the hydrolysis of the 31-43 alpha-gliadin-like fragment. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides new information of use when obtaining sourdough starters for bread making. Moreover, knowledge regarding lactobacilli capable of reducing the level of gliadin-like fractions, a toxic peptide for coeliac patients, has a beneficial health impact.

Amino Acids↗
PubMed2005

[Colorectal carcinoma in the young. Prognostic factors].

Colorectal carcinoma is the third most frequently diagnosed malignant neoplasm. Usually patients affected by this neoplasia belong to VI decade of life. However approximately 2-8% of tumors arise in patients with age under 40 years. Aim of the study was to analyse the results of surgical treatment of colorectal cancer in patients aged under forty. From January 1987 to December 2002, 46 patients under forty years with colorectal cancer underwent surgical procedure. No perioperative mortality was registered, and complications were evidenced in nine patients (20%). Actuarial five years survival was 33%, and overall mean survival was 53 months. Univariate and multivariate analyses identified as prognostic factors the tumor grade, Dukes' stage, nodal status, and length of symptoms.

Actuarial Analysis↗
PubMed2003

Polypropilene sling of the bulbar urethra for post-radical prostatectomy incontinence.

OBJECTIVE: We present details of a modification of the Stamey procedure using a polypropilene mesh to compress the corpus spongiosum of the bulbar urethra in the treatment of sphincteric incompetence following radical prostatectomy. MATERIALS AND METHODS: Between September 1999 and June 2000 nine patients 66-80 years old (mean age 74) with severe incontinence due to radical prostatectomy underwent the bulbourethral sling procedure with polypropilene (Prolene) mesh implant. After transperineal incision a 5cmx4cm rectangular prolene mesh was placed against the bulbar urethra and suspended by four prolene sutures transferred to a suprapubic incision through ligature carriers as in the four corner bladder and bladder neck suspension. If leakage recurred in the follow-up, a retightening procedure was performed in local anesthesia rescuing the prolene threads over a polypropilene mesh placed against the rectus fascia. Mean follow-up was 14 months (range 12-20). Continence status and post-void residual volume were evaluated after 1, 3 and 6 months post-operatively and successively every 3 months. RESULTS: At the present follow-up considering the results of the retightening procedure five out of nine patients were cured, two out of nine improved and two were unchanged. Five out of nine patients reported slight to mild perineal/genital discomfort which disappeared in four at three months post-operatively. No patients required mesh removal for complications. CONCLUSIONS: The male bulbourethral sling procedure using a polypropilene mesh is safe but further experience is needed to establish this procedure as plausible alternative for the treatment of post-radical prostatectomy urinary incontinence.

Aged↗
PubMed2003

Characterization of sourdough lactic acid bacteria based on genotypic and cell-wall protein analyses.

AIMS: To evaluate the effectiveness of two independent methods in differentiating a large population of lactic acid bacteria (LAB) isolated from wheat flours and sourdoughs and to correlate eventual differences/similarities among strains with their geographical origin and/or process parameters. METHODS AND RESULTS: One hundred fifty strains belonging to Lactobacillus spp. and Weissella spp., plus eight type strains, one for each species, and two unidentified isolates, were characterized by randomly amplified polymorphic DNA (RAPD) and SDS-PAGE of cell-wall proteins. The RAPD analysis separated the eight type strains but did not always assign all the strains of a species to the same group, while SDS-PAGE cell-wall protein profiles were species-specific. Frequently, strains isolated from sourdoughs of the same geographical origin or produced by similar raw material/process parameters showed similar RAPD and/or cell-wall profiles. CONCLUSIONS: The combined use of the RAPD and cell-wall protein analysis represents a useful tool to classify large adventitious microbial populations and to discriminate the diversity of the strains. SIGNIFICANCE AND IMPACT OF THE STUDY: This study represents a typing of a large collection of flour/sourdough LAB and provides evidence of the advantage of using two independent methods in the classification and traceability of microorganisms.

Bacterial Proteins↗
PubMed2003

Prevalence of carotid stenosis in type 2 diabetic patients asymptomatic for cerebrovascular disease.

Stroke, with an incidence of 2.5 x 10(3) yr(-1) (95% CI, 2.3-2.8 x 10(3) yr(-1)), is the third most frequent cause of death and the first cause of disability in western society. Diabetes is an important risk factor for ischaemic stroke, second only to hypertension, whereas it does not seem to be associated with an increased risk of haemorrhagic stroke. The incidence of stroke in men and women between 45 and 74 yr has been found to be 2.5 and 3.5 times higher in diabetics than in non-diabetic subjects, with a relative risk higher in females than in males with diabetes and greater in both sexes in the 50-to-60-yr age group but decreased in subjects who were 70 and above. It is known that there is an association between ischaemic stroke and carotid stenosis. However, the prevalence of carotid stenosis in Type 2 diabetes mellitus (T2DM) patients has not been well investigated, mainly in the Italian diabetic population. Therefore, the aim of this study was to evaluate the prevalence of carotid artery stenosis in a population of T2DM patients asymptomatic for cerebrovascular disease selected from the files of the Diabetes Clinics, and from the computerised files of General Practitioners (GPs). Three hundred and sixty-five subjects were examined: 187 were non-diabetic (89 males, 98 females) and 178 were T2DM patients (82 males, 96 females). The mean age of all the subjects was 67 +/- 7.8 yr; 66 +/- 7.9 for the non-diabetic subjects and 67 +/- 7.5 yr in the diabetic subjects. In the echo-Doppler examination of the carotid, a degree of stenosis ranging 10-99% was recorded in 143/365 subjects (39.1%), 49/187 non-diabetics (26.2%) and 94/178 diabetics (52.8%). The differences were highly significant (p < 0.001). Severe stenosis was recorded in 17/143 subjects (12%); 12 of these were diabetic (70%) and 5 non-diabetic (30%). The diabetics were three times more likely to develop carotid stenosis than the non-diabetics with an odds ratio of 3.152, (95% CI, 2.032-4.889).

Aged↗
PubMed2002

Latent bioactive peptides in milk proteins: proteolytic activation and significance in dairy processing.

After a brief description of the properties of bioactive peptides, the proteolytic activation of the bioactive sequences from milk protein precursors is discussed. The ability of proteolytic enzymes from various sources, especially from lactic acid bacteria, to release bioactive peptides and the physiological and biotechnological significance of these peptides in dairy products are reviewed.

Amino Acid Sequence↗
PubMed2001

Microbiological and biochemical characteristics of Canestrato Pugliese cheese made from raw milk, pasteurized milk or by heating the curd in hot whey.

Canestrato Pugliese cheeses were produced from raw ewes' milk (R and R(II) cheeses), pasteurized ewes' milk (P cheese) and by heating the curd in hot whey according to a traditional protocol (T cheese). R(II) differed from R cheese mainly by having been produced from raw milk with a higher number of somatic cells, 950.000 vs. 750.000 ml(-1), respectively. Compared to P and T cheeses, R and R(II) cheeses had a higher concentration (one or two orders of magnitude) of cheese-related bacteria such as adventitious mesophilic lactobacilli, enterococci and staphylococci. At the end of ripening, all cheeses contained less than 1.0 log cfu g(-1) of total and fecal coliforms, and Escherichia coli and Staphylococcus aureus were not detected. As shown by phenotypic identification and RAPD-PCR, R cheese contained the largest number of mesophilic lactobacilli species and the greatest diversity of strains within the Lactobacillus plantarum species. Primary proteolysis did not differ appreciably among the cheeses. On the contrary, both urea-PAGE and the RP-HPLC analyses of the water-soluble N fractions showed the more complex profiles in cheeses produced by raw milks. R and R(II) cheeses had the highest values of water-soluble N/total N (ca. 30%) and the highest concentration of total free amino acids (ca. 40 mg g(-1) which approached or exceeded those reported for Italian cheeses with very high level of proteolysis during ripening. The main differences between R-R(II) and P-T cheeses were the concentrations of aspartic acid, proline, alanine, isoleucine, histidine and lysine. The water-soluble extracts of R and R(II) cheeses contained levels of amino-, imino- and di-peptidase activities, which were about twice those found in P and T cheeses. Cheeses differed slightly in the concentration of total free fatty acids that ranged between 1673 and 1651 mg kg(-1) in R and R(II) cheeses, and 1397 and 1334 mg kg(-1) in P and T cheeses. Butyric, caproic, capric, palmitic, oleic and linoleic acids were found at the highest concentrations.

Animals↗
PubMed2001

Amino acid catabolism in cheese-related bacteria: selection and study of the effects of pH, temperature and NaCl by quadratic response surface methodology.

AIMS: To screen the cystathionine lyase and L-methionine aminotransferase activities of cheese-related bacteria (lactococci, non-starter lactobacilli and smear bacteria) and to determine the individual and interactive effects of temperature, pH and NaCl concentration on selected enzyme activities. METHODS AND RESULTS: A subcellular fractionation protocol and specific enzyme assays were used, and a quadratic response surface methodology was applied. The majority of the strains, 21 of 33, had detectable cystathionine lyase activity which differed in the specificity. Aminotransferase activity on L-methionine was observed in only three strains. The cystathionine lyase activities of Lactobacillus reuteri DSM20016, Lactococcus lactis subsp. cremoris MG1363, Brevibacterium linens 10 and Corynebacterium ammoniagenes 8 and the L-methionine aminotransferase activity of Lact. reuteri DSM20016 had temperature and pH optima of 30-45 degrees C, and 7.5-8.0, respectively. As shown by the quadratic response surface methodology these enzymes retained activities in the range of temperature, pH and NaCl concentration which characterized the cheeses from which the bacteria originated. CONCLUSION: The enzyme activities may have a role in flavour development during cheese ripening. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of this work contribute to the knowledge about the amino acid catabolic enzymes in order to improve cheese ripening.

Amino Acids↗
PubMed2001

Characterization of non-starter lactic acid bacteria from Italian ewe cheeses based on phenotypic, genotypic, and cell wall protein analyses.

Non-starter lactic acid bacteria (NSLAB) were isolated from 12 Italian ewe cheeses representing six different types of cheese, which in several cases were produced by different manufacturers. A total of 400 presumptive Lactobacillus isolates were obtained, and 123 isolates and 10 type strains were subjected to phenotypic, genetic, and cell wall protein characterization analyses. Phenotypically, the cheese isolates included 32% Lactobacillus plantarum isolates, 15% L. brevis isolates, 12% L. paracasei subsp. paracasei isolates, 9% L. curvatus isolates, 6% L. fermentum isolates, 6% L. casei subsp. casei isolates, 5% L. pentosus isolates, 3% L. casei subsp. pseudoplantarum isolates, and 1% L. rhamnosus isolates. Eleven percent of the isolates were not phenotypically identified. Although a randomly amplified polymorphic DNA (RAPD) analysis based on three primers and clustering by the unweighted pair group method with arithmetic average (UPGMA) was useful for partially differentiating the 10 type strains, it did not provide a species-specific DNA band or a combination of bands which permitted complete separation of all the species considered. In contrast, sodium dodecyl sulfate-polyacrylamide gel electrophoresis cell wall protein profiles clustered by UPGMA were species specific and resolved the NSLAB. The only exceptions were isolates phenotypically identified as L. plantarum and L. pentosus or as L. casei subsp. casei and L. paracasei subsp. paracasei, which were grouped together. Based on protein profiles, Italian ewe cheeses frequently contained four different species and 3 to 16 strains. In general, the cheeses produced from raw ewe milk contained a larger number of more diverse strains than the cheeses produced from pasteurized milk. The same cheese produced in different factories contained different species, as well as strains that belonged to the same species but grouped in different RAPD clusters.

Animals↗
PubMed2001

Microbiological and biochemical properties of canestrato pugliese hard cheese supplemented with bifidobacteria.

Canestrato Pugliese cheeses from ewe milk were produced according to a traditional protocol and by adding 7.0 log10 cfu of fresh cells per gram of Bifidobacterium bifidum Bb02, Bifidobacterium longum Bb46, or both species. The traditional technology was modified slightly to favor the survival of probiotic microorganisms. After 56 d of ripening, the survival of B. bifidum Bb02 and B. longum Bb46 was 6.0 and 5.0 log10 cfu/g, respectively. After 19 d cheeses contained ca. 7.0 log10 cfu/g of bifidobacteria. Compared to traditional cheese, the addition of bifidobacteria seemed to support the growth and survival of mesophilic lactobacilli and Streptococcus thermophilus, used as starter, during ripening. No significant differences were observed in the main chemical composition, and only a slightly higher concentration of acetic acid was found in cheeses with bifidobacteria added. On the contrary, alpha- and beta-galactosidase activities were markedly more pronounced in the presence of bifidobacteria, especially with B. bifidum Bb02. In contrast with traditional cheese, the lactose was completely hydrolyzed in cheeses made with bifidobacteria. Urea-PAGE electrophoresis of the pH 4.6-soluble and pH 4.6-insoluble N fractions did not show appreciable variations. Only the reversed-phase-HPLC analysis of the pH 4.6-soluble N showed a slightly more complex profile in the presence of bifidobacteria. This finding was in agreement with the higher value of the pH 4.6-soluble N/total N ratio and with the more pronounced amino-, imino-, and dipeptidase activities found in all the cheeses with the bifidobacteria added, especially B. bifidum Bb02. No differences were found in the free amino acid and free fatty acid contents. The amino acids glutamic acid, valine, proline, leucine, and lysine and the fatty acids butyric, caproic, capric, and oleic acids were found at the highest concentrations. The sensory evaluation did not show significant differences, and Canestrato Pugliese cheeses were characterized by small and uniformly distributed eyes, were pale yellow, had an elastic consistency and a Pecorino-like smell, were very salty, and tended to be moderately piquant.

Amino Acids↗
PubMed2000

Tension-free vaginal mesh repair for anterior vaginal wall prolapse.

OBJECTIVES: We determined the efficacy of the use of a tension free prolene mesh to correct a grade III anterior vaginal wall prolapse recurrence. METHODS: Twelve women (mean age 65.6 years) with stress urinary incontinence (SUI) (4 type II and 1 type III) and bladder prolapse entered the study. After vaginal incision a pretailored polypropylene mesh was fixed to its four angles by absorbable sutures to the urethropelvic ligaments and pubocervical fascia anteriorly and to the cardinal ligaments and pubocervical fascia posteriorly. When present, a posterior descensus was corrected during the same procedure. SUI was treated with the tension-free vaginal tape procedure (TVT) through a separate vaginal incision over the mid-urethra. RESULTS: All patients were available for postoperative pelvic examination at 3-month intervals, for a mean follow-up of 20.5 months (range 15-32). Nine patients were considered cured (no cystocele recurrence) while in 3 patients a grade 1 asymptomatic cystocele was present postoperatively (asymptomatic). No significant postoperative pain was reported by the patients. CONCLUSIONS: This study confirms that in patients with moderate cystocele a tension-free mesh to support bladder base and neck effectively treats the cystocele. It is particularly recommended in the treatment of previous failure with traditional techniques and when the quality of suspending tissue is poor or defective. A long-term study on a large number of patients is still warranted to confirm and validate its clinical use.

Aged↗
PubMed1999

Lactobacillus sanfranciscensis CB1: manganese, oxygen, superoxide dismutase and metabolism.

The latency phase, growth rate, cell yield and end-products of Lactobacillus sanfranciscensis CB1 were affected by oxygen and the supply of 225 microM Mn2+. Mn2+ was especially related to the highest substrate consumption. Aerobiosis and Mn2+ supply were responsible for the highest superoxide dismutase activity. An auto-inhibitory accumulation of H2O2 meant that the survival of air-grown cells supplied with Mn2+ rapidly decreased during the stationary phase. As shown by sodium dodecyl sulfate/polyacrylamide gel electrophoresis, Mn2+ supply influenced protein expression. As shown by non-denaturating zymograms, Lb. sanfranciscensis CB1 expressed an approximately 12.5-kDa superoxide dismutase, which is probably Mn-dependent. The enzyme was insensitive to H2O2 treatment, was not induced by the presence of paraquat under aerobic conditions and was relatively stable at pH 4.0. Sourdoughs that contained high levels of oxygen enhanced cell growth, acidification and acetic acid production by Lb. sanfranciscensis CB1.

Anaerobiosis↗