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Raffaele D'Amelio

Publications and source records attributed to Raffaele D'Amelio.

11 recordsLinked to original sources
PubMed2006

Genotyping of Bacillus anthracis strains based on automated capillary 25-loci multiple locus variable-number tandem repeats analysis.

BACKGROUND: The genome of Bacillus anthracis, the etiological agent of anthrax, is highly monomorphic which makes differentiation between strains difficult. A Multiple Locus Variable-number tandem repeats (VNTR) Analysis (MLVA) assay based on 20 markers was previously described. It has considerable discrimination power, reproducibility, and low cost, especially since the markers proposed can be typed by agarose-gel electrophoresis. However in an emergency situation, faster genotyping and access to representative databases is necessary. RESULTS: Genotyping of B. anthracis reference strains and isolates from France and Italy was done using a 25 loci MLVA assay combining 21 previously described loci and 4 new ones. DNA was amplified in 4 multiplex PCR reactions and the length of the resulting 25 amplicons was estimated by automated capillary electrophoresis. The results were reproducible and the data were consistent with other gel based methods once differences in mobility patterns were taken into account. Some alleles previously unresolved by agarose gel electrophoresis could be resolved by capillary electrophoresis, thus further increasing the assay resolution. One particular locus, Bams30, is the result of a recombination between a 27 bp tandem repeat and a 9 bp tandem repeat. The analysis of the array illustrates the evolution process of tandem repeats. CONCLUSION: In a crisis situation of suspected bioterrorism, standardization, speed and accuracy, together with the availability of reference typing data are important issues, as illustrated by the 2001 anthrax letters event. In this report we describe an upgrade of the previously published MLVA method for genotyping of B. anthracis and apply the method to the typing of French and Italian B. anthracis strain collections. The increased number of markers studied compared to reports using only 8 loci greatly improves the discrimination power of the technique. An Italian strain belonging to the B branch was described, and two new branches, D and E, are proposed. Owing to the upgrading achieved here, precise genotyping can now be produced either by automated capillary electrophoresis, or by the more accessible but slower and for some markers slightly less accurate agarose gel methodology.

Automation↗
PubMed2006

Relationship between biofilm formation, the enterococcal surface protein (Esp) and gelatinase in clinical isolates of Enterococcus faecalis and Enterococcus faecium.

One-hundred and twenty-eight enterococcal isolates were examined for their ability to form biofilm in relation to the presence of the gene encoding the enterococcal surface protein (esp), production of gelatinase and to the source of isolation. Neither esp nor gelatinase seemed to be required for biofilm formation: both Enterococcus faecalis and Enterococcus faecium did not show a correlation between the presence of either esp or the production of gelatinase and biofilm formation. However, in E. faecium while esp was found in isolates from either source, the presence of both esp and biofilm together was only found in strains from clinical settings, suggesting that there exists a synergy between these factors which serves as an advantage for the process of infection.

Bacterial Proteins↗
PubMed2006

Nerve growth factor and brain-derived neurotrophic factor levels in patients with rheumatoid arthritis treated with TNF-alpha blockers.

Twenty consecutive rheumatoid arthritis (RA) patients (mean age 50.4 +/- 10.5 years; 17 females; mean disease duration 5.78 +/- 3.75 years) enrolled for tumor necrosis factor-alpha (TNF-alpha) blockers therapy (10 infliximab and 10 etanercept) were selected. Before starting therapy, 3 and 6 months thereafter all patients were evaluated for disease activity score (DAS), erythrocyte sedimentation rate (ESR), serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF). After 3 and 6 months a significant reduction in DAS, ESR, CRP, and IL-6 was observed, whereas no significant differences of NGF and BDNF serum levels were found. These preliminary results confirm that TNF-alpha blockers significantly improve disease activity and inflammation in RA; nevertheless further studies are needed to explain the mechanisms regulating NGF and BDNF release in RA patients treated with TNF-alpha blockers.

Antibodies, Monoclonal↗
PubMed2003

Probable dengue virus infection among Italian troops, East Timor, 1999-2000.

To investigate the attack rate and risk factors for probable dengue fever, a cross-sectional study was conducted of an Italian military unit after its deployment to East Timor. Probable dengue was contracted by 16 (6.6%) of 241 army troops and caused half of all medical evacuations (12/24); no cases were detected among navy and air force personnel.

Adult↗
PubMed2002

Vaccination policies in the military: an insight on influenza.

Influenza, despite its generally benign clinical course, is accompanied by absenteeism from work, acute suffering and even mortality, mainly in the elderly and in subjects who have high-risk medical conditions. Its prevention consists of strain specific vaccination, which must be repeated annually due to the high antigenic variability of the influenza virus. Influenza may represent an important obstacle to military readiness, particularly when considering its infectivity within closed communities. Despite such epidemiological situations, influenza vaccination is seldom included in the compulsory vaccination programme of the military on a global level. This may be due to several reasons, namely, a lack of confidence in the vaccine's effectiveness, the need for annual administrations (with expansion of economic and organisational efforts), false assumption that influenza is a disease with a minor impact, contradictory results of cost-effectiveness analyses (examples of which have yet to be made specifically for the military environment). The availability of more effective, economic and easy to administer vaccines, together with detailed and tailored cost-effectiveness analyses, may have a beneficial effect on the role the military plays in the fight against influenza across the globe.

Cost-Benefit Analysis↗
PubMedDate not supplied

Long-term immunogenicity of hepatitis B vaccination and policy for booster: an Italian multicentre study.

BACKGROUND: Universal anti-hepatitis-B vaccination of infants and adolescents was implemented in Italy in 1991. We undertook a multicentre study in previously vaccinated individuals to assess the duration of immunity and need for booster, over 10 years after vaccination. METHODS: In 1212 children and 446 Italian Air Force recruits vaccinated as infants and adolescents, respectively, we measured the concentrations of antibodies to hepatitis-B surface antigen (anti-HBs) and the presence of antibodies to hepatitis-B core antigen (anti-HBc) at enrollment; postimmunisation values were not available. Individuals positive for anti-HBc were tested for hepatitis B surface antigen (HBsAg) and hepatitis B viral DNA. Individuals with anti-HBs concentrations at 10 IU/L or more were regarded as protected; those with antibody less than 10 IU/L were given a booster dose and retested 2 weeks later. Individuals showing postbooster anti-HBs concentrations of less than 10 IU/L were offered two additional vaccine doses and retested 1 month after the third dose. FINDINGS: Protective anti-HBs concentrations were retained in 779 (64%, 95% CI 61.6-67) children and 398 (89%, 86.4-92.1) recruits. We recorded antibody amounts of less than 10 IU/L in 433 children (36%, 33-38.4) and 48 (11%, 7.9-13.6) recruits. One child and four recruits were positive for anti-HBc, but negative for HBsAg and hepatitis B viral DNA. Antibody concentrations were higher in recruits than in children (geometric mean titre 234.8 IU/L vs 32.1 IU/L, p=0.0001). 332 (97%) of 342 children and 46 (96%) of 48 recruits who received a booster showed an anamnestic response, whereas ten (3%) children and two (4%) recruits remained negative for anti-HBs or had antibody concentrations of less than 10 IU/L. Prebooster and postbooster antibody titres were strongly correlated with each other in both groups. All individuals given two additional vaccine doses (eight children and two recruits) showed anti-HBs amounts of more than 10 IU/L at 1 month after vaccination. INTERPRETATION: Strong immunological memory persists more than 10 years after immunisation of infants and adolescents with a primary course of vaccination. Booster doses of vaccine do not seem necessary to ensure long-term protection.

Adult↗
PubMedDate not supplied

Effects of mental stress on cardiovascular and endocrine response in Air Force Academy cadets.

OBJECTIVES: Pilots are exposed to the "stress of flight" and the chronically activated stress response may play an important role in circulatory system disease progression. We studied the effect of an experimental mental stress on cardiovascular and neuroendocrine activity, in Air Force Academy cadets, before and after one month intensive course. DESIGN: Nine cadets were submitted to a psychometric evaluation before Stroop test (ST), including Minnesota Multiphasic Personality Inventory, State and Trait Anxiety Inventory (STAI X1 and X2 form) and Reaction Scheme Test. After ST, subjects completed a STAI X1 form. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP) were monitored and serum prolactin (PRL), growth hormone (GH), adrenocorticotropin (ACTH) and cortisol levels were determined, during ST. The protocol was repeated at the end of the course. RESULTS: No significant differences were evident in PRL, GH and ACTH levels. Cortisol concentrations were significantly higher before the course. ST did not modify hormone secretion. ST induced a significant and reproducible elevation of HR and SBP. Basal HR, SBP and DBP values were significantly elevated after the course. Two subjects presented a particular psychometric profile, a different cardiovascular response to ST and did not pass the course. CONCLUSIONS: acute mental stress significantly activated cardiovascular response without modifying endocrine responses, in relation to the psychological profiles. A significant increase of cardiovascular parameters was present after the course, with enhanced dichotomy between the endocrine and sympathetic system, suggesting a careful evaluation and follow-up for circulatory system diseases in cadets.

Adrenocorticotropic Hormone↗