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P Mastrantonio

Publications and source records attributed to P Mastrantonio.

At least 19 recordsLinked to original sources
PubMed2007

Characterisation of invasive meningococcal isolates from Italian children and adolescents.

Meningococcal invasive disease is a life-threatening infection that affects mostly children and adolescents. The present study was performed during 2003-2005 to compare the phenotypic characteristics of meningococcal isolates from these two main groups at risk with those of isolates from other age groups to assess whether strategies for treatment and prevention implemented elsewhere can also be applied in Italy. The results showed that serogroup C meningococci were predominant, and that a dramatic increase in the circulation of strains with decreased susceptibility to penicillin was associated mainly with a prevalent phenotype C:2b:P1.5,2, which belongs to the hyper-virulent ST8/A4 cluster.

Adolescent↗
PubMed2004

Placental growth hormone in Down's syndrome screening.

A number of serum markers have been proposed to improve the sensitivity (and specificity) of the triple test, which, until now, has been the gold standard in second-trimester serum screening for Down's syndrome. Among them, human placental growth hormone (hPGH) has been proposed because of its significantly elevated serum levels in pregnancies affected by chromosomal aneuploidies. Our experience, on maternal serum stored from 32 Down's syndrome-affected pregnancies, confirms a slight but significant increase in hPGH levels compared with controls. These data summarized to that of the previous screening could give a calculated detection rate of 71.9%, better than that of the standard triple test alone (65.6%).

Adult↗
PubMed2003

Long-term predominance of a rare meningococcal phenotype in a small geographical area.

Reported here is a predominant clone of Neisseria meningitidis B:14:P1.13 that persisted over a 6-year period in the northernmost province of Italy, where it was responsible for a higher incidence of meningococcal disease compared to the rest of the country. Genetic relatedness of isolates was confirmed by multilocus sequence typing, pulsed-field gel electrophoresis and PorA variable region typing. All strains examined belonged to the ST44 complex/lineage III. Risk factors for infection were evaluated through a case-control study conducted with 21 cases and 63 age- and sex-matched controls. Risk factors for infection in the seven patients younger than 13 years were (i) residence in a rural area, (ii) exposure to passive smoke, and (iii) living in a home with rooms rented to tourists (all odds ratios infinite). The only risk factor for the older patients was previous influenza-like illness (odds ratio, 41.9; 95% confidence interval, 1.6-1068.9). Guidelines for the early treatment of patients and public information campaigns were successfully implemented to reduce disease transmission and the case fatality rate in the region.

Adolescent↗
PubMed2003

Analogous IgG subclass response to pertussis toxin in vaccinated children, healthy or affected by whooping cough.

The study of antigen specific IgG subclass distribution during disease, or during any other natural or artificial immunisation, can provide useful information on the kind of the immune response and the expected levels of protection. This is particularly true for diseases, such as pertussis in which the mechanisms underlying specific defence are still not completely understood. An investigation was therefore performed to evaluate the IgG subclass response to pertussis toxin (PT) in sera from 89 healthy vaccinated children and 131 vaccinated or unvaccinated children convalescent after a confirmed B. pertussis symptomatic infection. Antibody titres were expressed in arbitrary ELISA units/ml, and statistical analyses were performed. In unvaccinated convalescent children IgG1 and IgG3 were prevalent whereas in children immunised with two different acellular pertussis (aP) vaccines, both healthy and convalescent, IgG1, IgG2 and IgG4 antibodies were mainly produced. Maintenance of the same anti-PT antibody response pattern in healthy acellular pertussis vaccine recipients and in vaccinated children who later acquire the disease is an interesting result indicative of the priming effect induced by these vaccines in the direction of a relatively higher Th2 cell-polarisation of the immune response.

Antibodies, Bacterial↗
PubMed2003

A European survey of diagnostic methods and testing protocols for Clostridium difficile.

OBJECTIVE: To conduct a survey of the methods used in clinical microbiology laboratories in Europe to diagnose infection with Clostridium difficile. METHODS: A questionnaire was devised and sent to a co-ordinating member of the Study Group in each of eight European countries. This co-ordinator was in charge of forwarding the questionnaire to hospital laboratories arbitrarily selected. The number of laboratories in each country was determined on the basis of one laboratory for 10,000 beds of hospitalization. This questionnaire covered different aspects pertaining to Clostridium difficile associated to diarrhea (CDAD) diagnosis such as circumstances of request, criteria used for undertaking C. difficile investigations, methods used for the diagnosis, etc. RESULTS: A total of 212 questionnaires were completed and submitted for analysis: 87.7% of laboratories reported routinely performing C. difficile diagnostic tests. Methods used included toxin detection (93%), culture (55%), and glutamate dehydrogenase (GDH) detection (5.9%). Among the laboratories detecting toxins, different enzyme immunoassays (EIA) and cytotoxicity assays were used in 79% and 17.3% of cases, respectively. Among the different strategies reported, 4.8% were considered suboptimal for the diagnosis of C. difficile infections, but marked discrepancies could be observed between countries. The overall incidence (median) of CDAD was estimated at 1.1 for 1,000 patient admissions. CONCLUSION: The results of this study suggest marked discrepancies between laboratories and also between countries regarding the criteria by which C. difficile is investigated for, and the methods and the strategies that are used for the diagnosis of C. difficile. These discrepancies could be explained by the lack of clear guidelines for C. difficile diagnosis in each country, and by the importance that physicians attach to C. difficile. Precise guidelines for C. difficile diagnosis would be the first step to make possible accurate comparison of the incidence and the epidemiology of CDAD from one hospital to another or from one country to another.

Bacterial Proteins↗
PubMed2003

T-cell immune response assessment as a complement to serology and intranasal protection assays in determining the protective immunity induced by acellular pertussis vaccines in mice.

The relative value of antibodies and/or T-cell immune responses to Bordetella pertussis antigens in the immunity induced by acellular pertussis (aP) vaccines is still an open issue, probably due to the incomplete knowledge on the mechanisms of protective immunity to pertussis. The relevance of T-cell immune responses in protection from pertussis has been demonstrated in murine and human models of infection; thus, in this study, the ability of different vaccine preparations of three component (pertussis toxin, filamentous hemagglutinin, and pertactin) aP vaccines to induce T-cell responses was investigated in mice. All vaccine preparations examined passed the immunogenicity control test, based on antibody titer assessment, according to European Pharmacopoeia standards, and protected mice from B. pertussis intranasal challenge, but not all preparations were able to prime T cells to pertussis toxin, the specific B. pertussis antigen. In particular, one vaccine preparation was unable to induce proliferation and gamma interferon (IFN-gamma) production while the other two gave borderline results. The evaluation of T-cell responses to pertussis toxin antigen may provide information on the protective immunity induced by aP vaccines in animal models. Considering the critical role of the axis interleukin-12-IFN-gamma for protection from pertussis, our results suggest that testing the induction of a key protective cytokine such as IFN-gamma could be an additional tool for the evaluation of the immune response induced by aP vaccines.

Administration, Intranasal↗
PubMed2001

Laparoscopic Burch colposuspension: a randomized controlled trial comparing two transperitoneal surgical techniques.

OBJECTIVE: To compare the effectiveness of two transperitoneal laparoscopic Burch procedures. METHODS: The sample size required was 30 subjects per group to detect a statistically significant estimated difference of 15% between two surgical procedures with an alpha = 0.05 and a power of 0.7. Sixty women affected by genuine stress incontinence (GSI) were enrolled and randomly assigned to two groups of 30 women each. All women were treated with the transperitoneal laparoscopic Burch procedure using nonabsorbable sutures (group A) or Prolene mesh (Ethicon, Somerville, NJ) fixed with tacks or staples (group B). The failure rate was defined subjectively and objectively. The subjective evaluation was performed by asking the women to rate their urine loss on a visual analog scale. The objective evaluation was a clinical evaluation using multichannel urodynamic studies. RESULTS: The subjective failure rate was not significantly different between the two groups at 3 months (0% for both groups), 6 months (3.7% versus 3.8% for groups A and B, respectively), and 12 months (7.4% versus 15.4% for groups A and B, respectively) after surgery. At 3 months (3.7% versus 3.8% for groups A and B, respectively) and 6 months (7.4% versus 15.4% for groups A and B, respectively) follow-up, the objective failure rate was not significantly different between the two groups. However, at 12 months after the surgical procedure, the objective failure rate was significantly lower in group A than in group B (11.1% versus 26.9%, respectively; P <.05). CONCLUSION: Transperitoneal laparoscopic Burch colposuspension performed using sutures was more effective than the mesh technique.

Colposcopy↗
PubMed2001

Transdermal hormone replacement therapy in postmenopausal women with uterine leiomyomas.

OBJECTIVE: To evaluate the effects of transdermal hormone replacement therapy (HRT) on uterine and leiomyoma size and on uterine bleeding patterns in postmenopausal women with uterine leiomyomas. METHODS: The required sample size was calculated to be 30 subjects per group to detect an effect on the size of one standard deviation (SD) with an alpha value of 0.05 (two-sided) and a power 1 - delta = 0.8. At the end of the study, the power analysis showed a value of beta = 0.826. Seventy postmenopausal women with uterine leiomyomas were enrolled and treated for 12 cycles of 28 days each with transdermal 17 beta-estradiol (E(2)) patches plus oral medroxyprogesterone acetate continuously added (group A) or with calcium carbonate (group B). At entry and every three cycles, uterine and leiomyoma dimensions were measured by transvaginal ultrasonography. To evaluate the effect of transdermal HRT on the characteristics of uterine bleeding, 35 healthy postmenopausal women without uterine leiomyomas (group C) were enrolled and treated with the same regimen as group A. A daily diary was used to record the abnormal uterine bleeding episodes, and a rank scale was used to assess the severity of bleeding. RESULTS: There were no significant changes in mean uterine or leiomyoma size between groups A and B, or in each group compared with basal values. No significant difference was detected between groups A and C in uterine bleeding patterns. CONCLUSION: Transdermal HRT did not increase the size of uterine leiomyomas or affect uterine bleeding patterns in postmenopausal women.

Administration, Cutaneous↗
PubMed2001

Rifampicin-resistant meningococci causing invasive disease: detection of point mutations in the rpoB gene and molecular characterization of the strains.

Mutations in the rpoB gene affecting two amino acids were found in eight rifampicin-resistant Neisseria meningitidis group B and C strains isolated in Italy. The Asp542-->Val substitution, documented for the first time in N. meningitidis, was found in four of the isolates; the His552-->Tyr or Asn substitution in the other four resistant strains. Mutations in the mtr gene did not seem to be involved in the resistance since the same mutations occurred in both resistant and susceptible strains. Two different clusters were identified among these resistant strains, without any correlation with the specific mutations detected in the rpoB gene.

Antibiotics, Antitubercular↗
PubMed2001

Molecular typing and long-term comparison of clostridium difficile strains by pulsed-field gel electrophoresis and PCR-ribotyping.

Thirty-two related and 68 unrelated isolates of Clostridium difficile, isolated in different Italian hospitals since 1987, were analysed by PFGE and PCR-ribotyping to investigate their genetic relatedness. The isolates were classified into 28 groups by PFGE and 20 ribotypes by PCR-ribotyping. A single clone of C. difficile was recognised as the cause of three geographically and chronologically distant outbreaks. The correlation between PFGE and PCR-ribotyping results was good, with agreement for 77 (84%) of the 92 isolates typed by both methods. However, among sporadic isolates the discriminatory power of PFGE was more evident. Eight isolates that were untypable by PFGE could be analysed by PCR-ribotyping. The dendrograms generated showed that the genetic relatedness of the C. difficile isolates obtained by both techniques was comparable. The majority of the isolates in recent years appeared to be genetically unrelated to isolates from past infections. However, two clonal groups identified in all time periods had a common origin and this seems to indicate that they share some advantageous biological characteristics. The constant monitoring of C. difficile epidemiology will allow acquisition of further important data on this nosocomial pathogen.

Clostridioides difficile↗
PubMed2001

Molecular and genomic analysis of genes encoding surface-anchored proteins from Clostridium difficile.

The gene slpA, encoding the S-layer precursor protein in the virulent Clostridium difficile strains C253 and 79--685, was identified. The precursor protein carries a C-terminal highly conserved anchoring domain, similar to the one found in the Cwp66 adhesin (previously characterized in strain 79--685), an SLH domain, and a variable N-terminal domain mediating cell adherence. The genes encoding the S-layer precursor proteins and the Cwp66 adhesin are present in a genetic locus carrying 17 open reading frames, 11 of which encode a similar two-domain architecture, likely to include surface-anchored proteins.

Amino Acid Sequence↗
PubMed2001

Reactogenicity and immunogenicity at preschool age of a booster dose of two three-component diphtheria-tetanus-acellular pertussis vaccines in children primed in infancy with acellular vaccines.

OBJECTIVES: To determine the reactogenicity and immunogenicity of a fourth dose of 2 three-component acellular pertussis vaccines combined with diphtheria-tetanus-acellular pertussis (DTaP) when administered at preschool age to children primed in infancy with 3 doses of the same DTaP and who had received a diphtheria-tetanus (DT) dose at the age of 12 months. SETTING: Local health units of 4 Italian regions. STUDY DESIGN: Three thousand five hundred twenty-two children, who had been randomized in the first year of life to be immunized with a DTaP vaccine by either SmithKline Beecham or Chiron Biocine, were offered a booster of the same vaccine or, if refusing, a DT vaccine at the age of 5 to 6 years. Families of children were aware of the vaccine administered. The occurrence of adverse events was compared between the children who received a DTaP booster and those boosted with a DT only. Antibody titers to pertussis vaccine components (pertussis toxin, filamentous hemoagglutinin, and pertactin) were determined on 558 paired sera taken before and 30 days after the DTaP booster administration. RESULTS: Four episodes of temperature >/=39.5 degrees C, 2 in each DTaP group, were recorded. Fever >/=38 degrees C occurred infrequently in both DTaP and DT recipients (DTaP range: 2.5%-2.8%; DT range: 0%-4.8%), as did irritability (DTaP range: 10.1%-11.7%; DT range: 7.4%-12.6%). The frequency of local reactions was significantly higher for DTaP recipients (range: 44.0%-52.8%), with respect to DT recipients (range: 29.5%-44.4%). Extensive local reactions were observed in 1.2% of DTaP recipients and in.5% of DT recipients. Both DTaP vaccines induced high antibody titers against pertussis toxin, filamentous hemoagglutinin, and pertactin, with an increase of >10 times the prebooster geometric mean titers. CONCLUSIONS: A booster dose of DTaP at preschool age in children primed with the same acellular pertussis vaccine is safe and immunogenic. However, the frequency of local reactions is higher compared with that following primary immunization and with that following booster with DT only, and parents should be informed of the potential for these reactions to occur.

Child↗
PubMed2001

Sustained efficacy during the first 6 years of life of 3-component acellular pertussis vaccines administered in infancy: the Italian experience.

BACKGROUND: In 1992-1993, a randomized, double-blind, placebo-controlled clinical trial of two 3-component acellular pertussis vaccines was started in 4 of Italy's 20 regions. During the trial, the children had been randomized to receive 3 doses of 1 of 2 acellular pertussis vaccines combined with diphtheria and tetanus toxoids (DT) or of a DT vaccine only, at 2, 4, and 6 months of age. Both diphtheria-tetanus-acellular pertussis (DTaP) vaccines, 1 manufactured by SmithKline Beecham (DTaP SB; Infanrix) and 1 manufactured by Chiron Biocine (DTaP CB; Triacelluvax), contain pertussis toxin (PT), filamentous hemagglutinin, and pertactin. The results of the first period of follow-up, which ended in 1994 (stage 1), showed that both vaccines had a protective efficacy of 84% in the first 2 years of life; when the trial's follow-up was extended under partial blinding until the participating children had reached 33 months of age (stage 2 of the follow-up), these high levels of efficacy had persisted. Therefore, the objective of this study was to estimate the persistence of protection from 3 to 6 years of age of the 2 3-component DTaP vaccines administered as primary immunization in infancy. METHODS: An unblinded prospective longitudinal study of vaccinated and unvaccinated children in 4 Italian regions, with active surveillance of cough, was conducted by study nurses, and Bordetella pertussis infections were confirmed laboratory. The present study (stage 3) included those children who completed stage 2 of the follow-up and were still under active surveillance as of October 1, 1995, accounting for 4217 children who had received DTaP SB (representing 94% of the vaccine's recipients in the initial phase of the trial), 4215 who had received DTaP CB (95% of the original recipients), and 266 who had received DT only (18% of the original recipients). Because the parents of most of the original DT placebo group accepted pertussis vaccination during stage 2 in 1995, an additional 856 children were recruited in the DT group at the initiation of stage 3. These additional children were identified from the census list of children born in the same period and living in the same areas as the trial participants but who had been vaccinated in infancy with DT only. Eligible children were included in stage 3 if they had no history of either pertussis or pertussis vaccination and if a serum sample obtained at the time of enrollment had undetectable immunoglobulin G (IgG) against PT. Parental consent to participate in the study was obtained. Active surveillance for pertussis was conducted in the field by 72 study nurses through monthly contact with each family in the study. A cough episode that lasted >/=7 days was considered to be a laboratory-confirmed infection by Bordetella pertussis if at least 1 of the following 5 criteria (listed in hierarchic order) was met: 1) B pertussis was obtained from nasopharyngeal culture (culture-confirmed infection); 2) the enzyme-linked immunosorbent assay (ELISA) IgG or IgA titer against PT in the convalescent-phase serum sample increased by at least 100% compared with the acute-phase sample; 3) the PT-neutralizing titers in Chinese hamster ovary assay in the convalescent-phase sample increased by at least 4-fold compared with the acute-phase sample; 4) the ELISA IgG or IgA titer against filamentous hemagglutinin in the convalescent-phase sample increased by at least 100% and the culture or the polymerase chain reaction assay on the nasopharyngeal aspirate was negative for B parapertussis; and 5) the ELISA IgG PT titer in 1 of the 2 serum samples exceeded the geometric mean titer computed on convalescent sera of the children with a culture-confirmed B pertussis infection in each study group. Incidence of laboratory-confirmed B pertussis infection, using case definitions that varied in terms of duration and type of cough, was computed and the proportion of cases prevented among DTaP recipients in comparison with DT recipients was calculated. RESULTS: A total of 391 laboratory-confirmed infections were identified in the 3-year follow-up period (138 DTaP SB, 126 DTaP CB, 127 DT recipients, respectively). The mean duration of cough in children with laboratory-confirmed infection was 48, 47, and 70 days for the DTaP SB, DTaP CB, and DT recipients, respectively; the mean duration of spasmodic cough was 15, 13, and 23 days, respectively. When using the primary case definition (ie, laboratory-confirmed B pertussis infection and >/=14 days of spasmodic cough or >/=21 days of any cough), the efficacy was 78% for the DTaP SB vaccine (95% confidence interval [CI]: 71%-83%) and 81% for the DTaP CB vaccine (95% CI: 74%-85%). When using the case definition based on a more severe clinical presentation (>/=21 days of spasmodic cough), the vaccine efficacy was 86% (95% CI: 79%-91%) for both vaccines. When using the case definition based on milder clinical presentation (any cough for >/=7 days), the efficacy was 76% (95% CI: 69%-81%) for the DTaP SB vaccine and 78% (95% CI: 72%-83%) for the DTaP CB vaccine. CONCLUSIONS: The persistence of protection through 6 years of age suggests that the fourth DTaP dose could be postponed until preschool age in children who received 3-component acellular pertussis vaccines in infancy, provided that immunity to diphtheria and tetanus is maintained. Additional booster doses could be administered at older ages to reduce reactogenicity induced by multiple administrations and to optimize the control of pertussis in adolescents and young adults.

Age Factors↗
PubMed2001

Typing of Neisseria meningitidis isolates from patients with invasive disease by molecular analysis of porin genes.

Polymerase Chain Reaction-Restriction Fragment Length Polymorphism assay (PCR-RFLP) for porA and porB genes of Neisseria meningitidis was applied to type 64 strains isolated from cases of invasive disease in Italy. The technique was also successfully used on non-viable strains and on cerebrospinal fluid samples from patients with meningococcal meningitis diagnosed by PCR. RFLP patterns were obtained for all strains, including those nontypeable or nonsubtypeable by the serological methods. The results confirmed the usefulness of the PCR-RFLP for porA and porB genes of Neisseria meningitidis in differentiating strains belonging to the same serological type and provided discriminative patterns in the increased proportion of non serotypeable/serosubtypeable strains circulating in Italy in recent years.

Bacterial Outer Membrane Proteins↗
PubMed2001

[Prenatal diagnosis of beta-thalassemia. A study based in Calabria].

BACKGROUND: The aim of this study was to underline, given the well-known incidence of beta thalassemia in Calabria, the possibility of establishing a prevention programme based on an increased awareness among the population using information and health education, genetic consultancy to identify high-risk subjects and prenatal diagnosis. METHODS: Between January 1992 and December 1999, we analysed 181 high-risk couples for beta thalassemia using chorionic villi sampling (CVS) performed with an echoguided transcervical or transabdominal route. A steady rise was observed over the years in the number of couples asking for prenatal diagnosis, thus demonstrating that patients and doctors are increasingly aware of the importance of a correct prenatal diagnosis. The variability of molecular defects found and the number of complications linked to the technique used are underlined. RESULTS: Prenatal diagnosis revealed 46 fetuses with the disease (24.8%), 97 heterozygotes (53.2%) and 41 healthy fetuses (22%). Only one malformation was observed in the 41 healthy fetuses. The authors also report the incidence of complications linked to CVS. In overall terms, 2.2% of pregnancies ended in spontaneous abortions (4 cases) and 2.75% with preterm births (5 cases). These complications could not be correlated with gestational age at the time of biopsy or the number of attempts made to obtain an appropriate sample.

Female↗