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Indagine sul potere tossigeno di alcuni stipiti di Yersinia enterocolitica isolati da prodotti carnei trasformati
No full textCat scratch disease. Survey on the presence of Bartonella henselae among cats of Tuscany
No full textTo verify the presence of Bartonella henselae-infection in cats living in Tuscany (central Italy) serological and bacteriological surveys were carried out. The blood serum samples of 427 cats, 254 living in private houses and gardens and 173 in public or private catteries, were tested for anti-B. henselae antibodies by indirect immunofluorescence assay (IFA). Among these samples, 35 were examined by IFA to detect anti-bodies against Bartonella quintana. Bacteriological examinations were performed on the blood samples, collected in EDTA (ethylene diaminetetraacetic acid), of 18 cats (10 seropositive to B. henselae and 8 negative). From each of the same 18 specimens DNA was extracted and used as template in polymerase chain reaction (PCR). The primers p24E and p12B were employed in the PCR assay to amplify a 296 bp fragment of the Bartonella 16S rRNA gene. IFA detected 98 (22.95%) B. henselae-positive serum samples (40-40.82% from cats living in houses and gardens and 58-59.18% from cats of catteries) at different antibody titers (70 at 1:64 titer, 4 at 1:128, 22 at 1:256, 2 at 1:512). Among the 35 sera tested to detect antibodies against B. quintana, 9 (25.71%) resulted positive at 1:64 titer; all these samples showed higher antibody titers to B. henselae. Out of the 26 negative sera, 20 were negative to B. henselae too and 6 had antibodies against B. henselae at 1:64. Hemocultures gave negative results. PCR scored positive with DNA of 4 B. henselae-seropositive cats, two of which belonged to two children with cat scratch disease (CSD)
Preparation and Comparison of Hydrolase-Coated Plastics
Full text linkPolypropylene and polyethylene were coated with alpha-Chymotrypsin
(a-CT) or subtilisin Carlsberg (SubC) or Burkholderia
cepacia lipase (lipase BC) by different immobilization procedures,
such as physical adsorption and covalent linking. This
latter procedure was based on the chemical functionalization
of the plastic surface by oxygen gas plasma treatment. Immobilization
of the enzyme was carried out by using as cross-linking
agent i) glutaraldehyde (GA) or ii) N’-diisopropylcarbodiimide
(DIC) and N-hydroxysuccinimide (NHS). The effects of duration
of the plasma treatment and the type of the immobilization
procedure on the transesterification activity of the enzyme
were investigated. In general polypropylene resulted a better
support than polyethylene. Moreover, a-CT showed higher
transesterification activity when immobilized with GA, while for
SubC, DIC and NHS were better cross-linking agents than GA.
No activity was observed with these enzymes when immobilization
was carried out by physical adsorption. On the contrary,
lipase BC immobilized by physical adsorption was even more
active than the free enzyme. Concerning thermal stability, immobilized
SubC was less stable than the free enzyme. Overall,
these results show that plastics endowed with biocatalytic
properties could be obtained by simple immobilization protocols
and that optimal immobilization conditions depend on the
type of starting plastic, plasma treatment, cross-linking method,
and the nature of the enzyme
Il test di macroagglutinazione rapida nella diagnosi delle leptospirosi animali. Prove comparative con il test di microagglutinazione.
No full textChlamydiosi caprina. Ricerca di anticorpi in animali di importazione ed in greggi di alcune province italiane
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