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S Pignato

Publications and source records attributed to S Pignato.

At least 19 recordsLinked to original sources
PubMed2002

The impact of climate and traffic-related NO2 on the prevalence of asthma and allergic rhinitis in Italy.

BACKGROUND: Environmental factors are likely to be involved in explaining the wide geographical variation in asthma and atopic diseases that has been documented in many recent epidemiological studies. AIM: To evaluate to what extent climate and outdoor NO2 pollution can explain the geographical variation in the prevalence of asthma and allergic rhinitis, and to estimate the relative risk for exposure to different levels of these two factors. METHODS: The impact of climate and long-term exposure to nitrogen dioxide (NO2) pollution on asthma and allergic rhinitis was assessed in a cross-sectional study, carried out during 1998 to 2000 on young adults aged 20 to 44 years (n = 18 873), living in 13 areas from two different Italian climatic regions (subcontinental and Mediterranean). RESULTS: Mediterranean areas had a significantly higher prevalence of asthma-like symptoms (P < 0.001), higher annual mean temperature (16.2 degrees C vs. 12.9 degrees C), lower temperature range (16.0 C degrees vs. 22.1 degrees C) and lower NO2 levels (31.46 microg/m3 vs. 57.99 microg/m3) than subcontinental ones. Mediterranean climate was associated with an increased risk of wheeze (OR = 1.23; 95% CI 1.13 to 1.35), tightness in the chest (OR = 1.21; 95% CI 1.11 to 1.33), shortness of breath (OR = 1.21; 95% CI 1.08 to 1.36) and asthma attacks (OR = 1.19; 95% CI 1.07 to 1.31). After adjusting for climate, an increase of 18.3 microg/m3 in NO2 levels moderately increased the risk of asthma attacks (OR = 1.13; 95% CI 0.98 to 1.32), tightness in the chest (OR = 1.11; 95% CI 0.98 to 1.26) and wheeze (OR = 1.11; 95% CI 0.96 to 1.28). When the levels of outdoor NO2 exposure rose, the prevalence of allergic rhinitis increased significantly in the Mediterranean region (OR = 1.38; 95% CI 1.12 to 1.69), but not in the subcontinental one (OR = 1.03; 95% CI 0.83 to 1.28). CONCLUSION: Our results show that the prevalence of asthma increases when annual mean temperature increases and temperature range decreases. Furthermore, climate interacts with NO2 outdoor exposure, increasing the risk for allergic rhinitis in people exposed to high stable temperatures. A long-term role for the effect of traffic pollution on asthma is also suggested.

Adult↗
PubMed2000

Carbohydrate assimilation profiles of the first Italian Candida dubliniensis clinical isolates recovered from an HIV-infected individual.

A total of six Candida dubliniensis isolates were obtained during 1 year of monitoring by monthly swabs from the oral cavity of an asymptomatic human immunodeficiency virus-infected individual in Catania, Italy. To the authors' knowledge, this constitutes the first recovery of C. dubliniensis from a human in Italy. Our identification procedure was based on colony color on CHROMagar Candida and carbohydrate assimilation profiles obtained by two commercial systems: API ID 32C and API 20C AUX. Karyotyping by pulsed-field gel electrophoresis confirmed the phenotypic identification. The biocodes obtained with API 20C AUX and with API ID 32C were 6172134 and 7142140015, respectively, for all six isolates. Both biocodes corresponded to those described in the literature as being produced by most C. dubliniensis isolates with each of the two identification systems. Our results confirm that both API 20C AUX and API ID 32C are able to rapidly and accurately differentiate C. dubliniensis from C. albicans.

Candida↗
PubMed1999

Molecular characterization of the genera Proteus, Morganella, and Providencia by ribotyping.

The so-called Proteus-Providencia group is constituted at present by three genera and 10 species. Several of the recognized species are common opportunistic pathogens for humans and animals. Different methods based on the study of phenotypic characters have been used in the past with variable levels of efficiency for typing some species for epidemiological purposes. We have determined the rRNA gene restriction patterns (ribotypes) for the type strains of the 10 different species of the genera Proteus, Morganella, and Providencia. Visual inspection of EcoRV- and HincII-digested DNA from the type strains showed remarkably different patterns for both enzymes, but EcoRV provided better differentiation. Both endonucleases were retained to study a large number of wild and collection strains belonging to the different species. Clinical isolates of Proteus mirabilis, Proteus penneri, Morganella morganii, and Providencia heimbachae showed patterns identical or very similar to those of the respective type strains, so that groups of related patterns (ribogroups) were found to correspond to the diverse species. On the contrary, distinct ribogroups were detected within Providencia alcalifaciens (two ribogroups with both enzymes), Providencia rettgeri (four ribogroups with EcoRV and five with HincII), Providencia stuartii (two ribogroups with EcoRV), Providencia rustigianii (two ribogroups with HincII), and Proteus vulgaris (two ribogroups with both enzymes). The pattern shown by the ancient P. vulgaris type strain NCTC 4175 differed considerably from both P. vulgaris ribogroups as well as from the newly proposed type strain ATCC 29905 and from any other strain in this study, thus confirming its atypical nature. Minor differences were frequently observed among patterns of strains belonging to the same ribogroup. These differences were assumed to define ribotypes within each ribogroup. No correlation was observed between ribogroups or ribotypes and biogroups of P. vulgaris, P. alcalifaciens, P. stuartii, and P. rettgeri. Since, not only different species showed different rRNA gene restriction patterns, but also different ribogroups and ribotypes have been found in the majority of the species, ribotyping would be a sensitive method for molecular characterization of clinical isolates belonging to the genera Proteus, Morganella, and Providencia.

Bacterial Typing Techniques↗
PubMed1998

Safety and immunogenicity of a combined diphtheria-tetanus-acellular pertussis-hepatitis B vaccine administered according to two different primary vaccination schedules. Multicenter Working Group.

The reactogenicity and immunogenicity of a tetravalent diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HB) vaccine (SmithKline Beecham) were studied in 565 infants immunized according to one of two different schedules, at 2, 4 and 6 months of age (group A n = 208) or at 3, 5 and 11 months of age (group B n = 357). The incidences of local and general reactions within the first 8 days after vaccination were similar in the two groups of infants, the vast majority being mild in intensity and occurring within 2-3 days of vaccine administration. Severe local symptoms were rare: pain after 0.6% of all doses, redness after 0.5% and 1.3%, and swelling after 0.3% and 1.5%, in group A and B, respectively. Only one infant in group A and one in group B had a temperature > 39.0 degrees C. Both schedules proved satisfactory in obtaining high levels of antibodies against all antigens. The rates of serologic response against the different antigens reached 100% in both groups. Antibody titres against all vaccine components were elevated following both schedules, but after the third dose of vaccine geometric mean antibody titres (GMTs) against D toxoid, filamentous haemagglutinin (FHA), pertactin (PRN) and hepatitis B (HB) were significantly higher in the 3, 5, 11 group than after the 2, 4, 6 schedule. Antibody titres measured at 7 months of age in the group immunized at 2, 4 and 6 months were higher than those reached at 6 months of age in infants immunized at 3, 5 and 11 months, but FHA and PRN were within the range of DTPa vaccine with proven efficacy. We conclude that DTPa-HB vaccine was safe, well tolerated and highly immunogenic. Both vaccination schedules (2, 4, 6 and 3, 5, 11) can be considered suitable for mass immunization programmes.

Antibodies, Bacterial↗
PubMed1996

Phage types and ribotypes of Salmonella enteritidis in southern Italy.

Differently from other European countries, Southern Italy was affected by a considerable increase in human infections due to Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) only after 1990. On the present investigation, two groups of S. Enteritidis strains isolated during the low-incidence period 1980-1984 and the epidemic period 1990-1993, respectively, have been submitted to phage-typing and ribotyping in order to ascertain whether the epidemic increase was determined by the spread of a foreign bacterial clone or not. Among the 150 isolates relative to the aforesaid two periods, 12 different phage types (PTs) were observed. PT4 was the most common phage type among the strains isolated in 1980-1984 (61%) as well as in those of the epidemic period 1990-1993 (72%). PT8 was the second most frequent (33%) phage type in 1980-1984. It was substituted by PT1 (19%) in the 1990-1993 period. Analysis of rDNA patterns obtained after Hinc II digestions and Escherichia coli rRNA hybridizations showed 8 different patterns, A to H. The great majority of the strains studied (140 isolates, 93%) belonged to the ribotype A, showing a similar frequency both in 1980-1984 (36 of 39, 92%) and in 19901993 (104 of 111, 94%). The predominance of PT4 and ribotype A among both preepidemic and epidemic strains is in agreement with the hypothesis that host genetic diversity decline and modern farming practices in the poultry industry have facilitated a widespread dissemination of preexisting endemic strains. This hypothesis urges to plan new strategies in preventing S. Enteritidis infections.

Bacterial Typing Techniques↗
PubMed1995

Rambach agar and SM-ID medium sensitivity for presumptive identification of Salmonella subspecies I-VI.

The cultural characteristics of 112 Salmonella serovars belonging to subspecies I-VI were examined on Rambach agar and SM-ID medium. Colonies showing the typical red coloration were seen with 100 of 112 serovars assayed on SM-ID, and with 87 of 112 on Rambach agar. Atypical colourless colonies were observed on Rambach agar with ONPG-negative serovars S. Choleraesuis, S. Isangi, S. Typhi S. Worthington and S. Yoff of the subspecies I, S. II 52:d:e,n,x,z15 of the subspecies II, S. IV 6,7:z4,z24:- and S. IV 11:g,z51:- of the subspecies IV, and S. 40:z35:- belonging to S. bongori (V) species. Atypical blue, blue-green, blue-violet or violet colonies were observed on both media with all the ONPG-positive serovars of the subspecies IIIa (four of four strains) and IIIb (six of six strains) and with one of the two ONPG-positive (out of five) strains of the subspecies VI. Four serovars of S. bongori showed blue-green colonies on Rambach agar and typical red colonies on SM-ID, although they were all ONPG-positive. These results suggest that SM-ID medium is more sensitive than Rambach agar. However, the relatively low sensitivity of both media makes them suitable for use only in association with a traditional selective medium in both medical and environmental bacteriology, as well as for epidemiological purposes.

Culture Media↗
PubMed1995

Evaluation of new culture media for rapid detection and isolation of salmonellae in foods.

Conventional methods for Salmonella detection in foods can require up to 6 and at least 4 days. We have observed that the total analysis time can be reduced to 48 h by using Salmosyst broth as a liquid medium for both preenrichment and selective enrichment and Rambach agar (RA), a new selective plate medium. In samples of artificially contaminated ground beef Salmonella enteritidis was detected at a concentration of 0.4 CFU/g (10 CFU/25 g) by both a conventional method and the new method. Of 519 samples of foods for sale, 38 were Salmonella positive by both methods while 471 were negative. Nine samples which were negative by the conventional method were positive by the Salmosyst-RA method, while one sample positive by the first method was negative by the last. Therefore, the Salmosyst-RA method showed 97.9% sensitivity compared with the 81.2% sensitivity of the conventional method. The new method was also highly specific (98% specificity) in presumptive identification of Salmonella colonies. Furthermore, a 6-h preenrichment in Salmosyst broth has been proved sufficient for the repair of heat-injured Salmonella cells and for subsequent recovery by selective enrichment. In conclusion, the Salmosyst-RA method shows several advantages over both conventional and rapid noncultural methods: (i) only two media are required instead of the five media for conventional methods; (ii) in real time it is comparable to other rapid noncultural methods, which require 30 to 31 h; (iii) it is highly sensitive and specific; and (iv) it allows the isolation of Salmonella strains which can be characterized by appropriate phenotypic and genotypic typing methods for epidemiological investigations.

Animals↗
PubMed1994

Rapid identification of micro-organisms from urinary tract infections by beta-glucuronidase, phenylalanine deaminase, cytochrome oxidase and indole tests on isolation media.

Two commercially available media recommended for the isolation and rapid identification of Escherichia coli from urinary tract infections were supplemented with L-phenylalanine and L-tryptophan. The non-selective medium proved suitable for the direct detection of lactose fermentation, beta-glucuronidase and phenylalanine deaminase activities, indole production and the oxidase test. It was highly efficient in making a presumptive identification at species level of the most common gram-negative urinary pathogens, E. coli, Proteus mirabilis and Pseudomonas aeruginosa, that account for c. 85% of all urinary isolates. Among the gram-positive isolates, most colonies were non-fluorescent and could be separated into staphylococci and enterococci on the basis of the catalase test. Fluorescent colonies were found to be Staphylococcus haemolyticus isolates, 61% of which were fluorescent. The selective medium proved suitable for the same biochemical tests, with the exception of indole, which was not visible against the red colour of the medium. Therefore, the differentiation of P. mirabilis from other Proteus-Providencia species was impossible on this medium.

Amino Acid Oxidoreductases↗
PubMed1994

[Monitoring of low urinary tract infections in patients hospitalized with neurological diseases].

Bacteriological and systematic investigation has been carried on 135 confined to bed patients at the Neurological Department of the Policlinico of the University of Catania from January 1993 to June 1993, in order to estimate the frequency of the I.V.U. and the probable correlations with the basic nerve disease. Infections have been found with greater frequency between women and patients with catheter. The microorganisms most frequently isolated were: E. coli (36%) and Streptococcus faecalis (36%). Patients with positive urine culture have been treated in accordance with the indications of the bacterial identification. Particularly, surveys carried out in a group of patients suffering from cerebral stroke (81 cases), showed a frequent association between the I.V.U. and the beforesaid pathology. Similar results have been obtained in the two groups of patients submitted to 2 and to 3 drawings of urine respectively, practised at a distance of 5 of 5 days the one form the other.

Adolescent↗
PubMed1993

rRNA gene restriction patterns and biotypes of Shigella sonnei.

Shigella sonnei is a major agent of diarrhoeal disease in developed as well as in developing countries. Several phenotypic methods to define strain differences have been applied to this species of Shigella including, more recently, analysis of extrachromosomal and chromosomal DNA. In this study, 432 endemic and epidemic strains isolated between 1975 and 1991 in Italy, France and Switzerland were submitted to rRNA gene restriction pattern analysis, after digestion of whole-cell DNA by Hinc II, and to concomitant biotyping. Thirteen ribotypes, H1 to H13, and five biotypes, a, d, e, f, g, were detected. Ninety-five percent of the sporadic strains were assigned to ribotypes H1 to H4, which could be subtyped, except for H4, in different biotypes. Strains from each of seven different outbreaks had indistinguishable ribotype-biotype patterns. In contrast, 65 strains, isolated in Sicily in 1980 over an extended period of apparently epidemic increase of isolations and which had previously been considered to be a single bacterial clone on the basis of resistance pattern and phage type, were found to belong to two different and scarcely related ribotypes. Ribotyping and biochemical subtyping appear to be a useful epidemiological tool in studies on the circulation and distribution of strains of S. sonnei.

Bacterial Typing Techniques↗
PubMed1992

Molecular typing of Salmonella enterica subsp. enterica serovar Wien by rRNA gene restriction patterns.

Analysis of digested DNA from 40 Salmonella enterica subsp. enterica serovar Wien isolates revealed five different rRNA gene restriction patterns for HindIII (H1 to H5) and five for PstI (P1 to P5). The isolates had been selected on the basis of the year of isolation, the geographic origin and the antibiotic resistance pattern and were distinguished as follows: a) 13 pre-epidemic isolates from different French towns in 1958-69 and from Senegal in 1968; b) 7 epidemic isolates from Algiers in 1969; c) 20 post-epidemic isolates from different French and Italian towns in 1970-90. Three different rRNA patterns (H1P1, H3P3 and H4P4) were observed among the pre-epidemic isolates. Conversely, the epidemic isolates, which were characterized by the previously described large antibiotic resistance patterns and by the presence of 1.3 and 80-109 MDa plasmids, belonged to the same H1P1 ribotype. All but two post-epidemic isolates were of the H1P1 ribotype. The determination of rRNA gene restriction patterns together with the plasmid content proved to be useful for a better characterization of the serovar Wien endemic and epidemic isolates.

Animals↗
PubMed1992

Pyrazinamidase activity in Enterobacteriaceae.

Pyrazinamidase activity was tested in 1,033 strains of 15 different genera of Enterobacteriaceae. The test was performed by a simple method which reveals the production of pyrazionic acid by a heavy bacterial suspension in 0.2 ml of a 0.5% pyrazinecarboxamide solution in Tris-maleate (0.2 M, pH 6) buffer after incubation for 18 h at 37 degrees C. Positivity was revealed by the development of a pink to red color after addition of 2 drops of 1% extemporaneously prepared ferrous ammonium sulphate aqueous solution. Pyrazinamidase activity proved to be a useful characteristic for the differentiation of some species from other enterobacteria devoid of this property. Because of its simplicity, this test is suitable for its introduction into the miniaturized diagnostic kits for the identification of enterobacteria.

Amidohydrolases↗
PubMed1992

An enzymatic procedure for the confirmation of total coliforms and Escherichia coli enumeration from water.

A new procedure for the confirmation of total coliforms and Escherichia coli from presumptive most probable number (MPN) test is described. The procedure utilizes an enzymatic test apparatus composed of a couple of devices, one charged with ONPG-medium for the detection of beta-galactosidase, the other with PNPG-medium for the detection of beta-glucuronidase. The results obtained demonstrate that the procedure is sensitive, specific and accurate. Further, it presents some advantages from the practical point of view: the cost of the devices is relatively low, their use is extremely simple and short time consuming, a single thermostatic apparatus adjusted at 36 degrees C for the incubation of the devices is only required, the results can be obtained after 18 h without any apparatus for the lecture (e.g. UV apparatus), they are not submitted to subjective interpretation.

Colony Count, Microbial↗
PubMed1988

Interference of oral poliovirus vaccine on RIT 4237 oral rotavirus vaccine.

A vaccination trial, performed on 86 3-month-old infants, has shown that the ability of the RIT 4237 live attenuated rotavirus strain to induce seroconversion is dramatically reduced when administered with live poliovirus vaccine. In a subsequent trial performed on 93 infants the attempt to overcome the poliovirus interference by administering two doses of associated vaccines was unsuccessful. No interference by the RIT 4237 strain on live attenuated polioviruses was observed.

Administration, Oral↗
PubMed1987

Yeast-derived hepatitis B vaccine in thalassaemic patients: a preliminary report.

Preliminary results of a trial involving a yeast-derived hepatitis B vaccine administered to 41 transfusion-dependent thalassaemic patients and 2 patients with spherocytosis are reported. Twenty-microgram doses of HBsAg were administered according to either a 0, 1, and 6 month or 0, 1, and 2 month schedule. Serum specimens collected prior to vaccination, one month after each vaccine dose, and again at 5 and 15 months, were tested for HBV markers and ALT. To date, seroconversion (anti-HBs titres greater than 10 IU/l) was observed in 15%, 67%, and 86% of patients one month following the three vaccine doses, respectively. Although the study is still in progress, a comparison of these results with those previously obtained using plasma-derived vaccine indicates that seroconversion to the recombinant yeast-derived vaccine is at least as high as that obtained by plasma-derived vaccines in patients affected by thalassaemia major.

Adolescent↗
PubMed1985

Epidemiological value of the gamma-glutamyltransferase test in Salmonella typhimurium.

The simple and rapid method of Giammanco et al. (1980) has been used for the detection of the gamma-glutamyltransferase (gamma-GT) by means of a chromogenic substrate in 803 endemic and epidemic strains of Salmonella typhimurium from Southern Italy. About 20% of the strains have been proved gamma-GT negative. Both in endemic and epidemic isolates, negative and positive strains were respectively belonging to different phage types. The reported data suggest that the presence or absence of the gamma-GT in S. typhimurium is an epidemiological marker quickly and easily detectable by the described chromogenic test.

Chromogenic Compounds↗