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S Rosati

Publications and source records attributed to S Rosati.

At least 19 recordsLinked to original sources
PubMed2002

Identification of cow's milk in "buffalo" cheese by duplex polymerase chain reaction.

A duplex polymerase chain reaction (PCR) was developed to identify the milk of bovine and buffalo species in cheese products, particularly in mozzarella cheese, a typical Italian cheese made from buffalo's milk. Two sets of primers were designed on the basis of the alignment of the sequence codifying mitochondrial cyt b available in the GenBank database. The primers proved to be species-specific, giving rise to 279-bp (bovine) and 192-bp (buffalo) amplified fragments. Since the amplification conditions for bovine and buffalo primers were identical, a duplex PCR was successfully applied to identify the two species in a single reaction step. This technique, when used to test cheese products from the retail trade, allowed the detection of partial or even total substitution of cow's milk for buffalo's milk, in some cases in samples of cheese misleadingly labeled "pure buffalo" mozzarella.

Animals↗
PubMed2001

The A(y) problem for p-3He elastic scattering.

We present evidence that numerically accurate quantum calculations employing modern internucleon forces do not reproduce the proton analyzing power, A(y), for p- 3He elastic scattering at low energies. These calculations underpredict new measured analyzing powers by approximately 30% at E(c.m.) = 1.20 MeV and by 40% at E(c.m.) = 1.69 MeV, an effect analogous to a well-known problem in p-d and n-d scattering. The calculations are performed using the complex Kohn variational principle and the (correlated) hyperspherical harmonics technique with full treatment of the Coulomb force. The inclusion of the three-nucleon interaction does not improve the agreement with the experimental data.

Journal Article↗
PubMed2001

Increased bone marrow vascularization in patients with acute myeloid leukaemia: a possible role for vascular endothelial growth factor.

The present study demonstrated that the vessel number in bone marrow biopsies from acute myeloid leukaemia (AML) patients (n = 23) was significantly increased at diagnosis compared with normal bone marrow (P = 0.019) and was restored to normal levels after achieving complete remission (P = 0.03). The in vitro angiogenic potential of culture supernatant of AML cells was assessed using endothelial cell (EC) migration and proliferation assays. Increased EC migration and EC proliferation was induced in 7/20 and 19/20 AML supernatents respectively. The degree of in vivo neovascularization did not correlate with the ability of AML cells to stimulate in vitro endothelial cell migration and/or proliferation. This might be in part a result of the heterogeneous pattern of angiogenic factors produced by AML cells. The expression of different angiogenic factors was studied using reverse transcription polymerase chain reaction. Cells from 17/20 AML patients showed wide variation in spontaneous vascular endothelial growth factor (VEGF) expression, 4/19 expressed varied spontaneous blastic fibroblast growth factor mRNA levels and all patient samples showed spontaneous interleukin 8 mRNA expression. All AML samples expressed matrix metalloproteinase (MMP)-2 and/or MMP-9. VEGF mRNA expression correlated well with protein level (P = 0.006). A correlation was found between the degree of VEGF expression and neoangiogenesis (correlation coefficient = 0.448, P = 0.05). These results suggest that malignant cell proliferation, angiogenesis and VEGF expression are linked in AML and might contribute to the growth advantage of the malignant counterpart as a result of the paracrine production of growth factors produced by the surrounding endothelial cells.

Acute Disease↗
PubMed2000

Realistic calculation of the 3He + p (hep) astrophysical factor.

The astrophysical factor for the proton weak capture on 3He is calculated with correlated hyperspherical harmonic wave functions corresponding to a realistic Hamiltonian consisting of the Argonne v(18) two-nucleon and Urbana-IX three-nucleon interactions. The nuclear weak current has vector and axial-vector components with one- and many-body terms. All possible transitions connecting any of the p 3He S- and P-wave channels to 4He are considered. The S factor at a p 3He center-of-mass energy of 10 keV is predicted to be 10. 1x10(-20) keV b, a factor of approximately 4.5 larger than the value adopted in the standard solar model. The P-wave transitions are found to contribute about 40% of the calculated S factor.

Journal Article↗
PubMed2000

An accessory open reading frame (orf-x) of jaagsiekte sheep retrovirus is conserved between different virus isolates.

Jaagsiekte sheep retrovirus (JSRV) is the etiological agent of a contagious lung tumour of sheep known as sheep pulmonary adenomatosis (syn: ovine pulmonary carcinoma, jaagsiekte). JSRV exhibits a simple genetic organization, characteristic of the type D and type B retroviruses, with the canonical retroviral sequences gag, pro, pol and env encoding the structural proteins of the virion. An additional open reading frame (orf-x), of approximately 500 bp overlapping pol, is present in the only two complete sequences of JSRV published to date. Since very little information is available on the biology of JSRV it is important to establish if orf-x is conserved between different virus isolates. In this study we analysed the orf-x region of JSRV isolates collected from the United Kingdom, Italy, Spain and South Africa. In addition we also analysed the presence of orf-x in JSRV-related endogenous sequences (enJSRVs) present in the sheep genome. Orf-x was highly conserved in all the exogenous isolates (n=10) and in most of the endogenous sequences (n=8). Thus orf-x may be an accessory gene of JSRV and haves a biological function which might be advantageous to JSRV. Phenetic analysis conducted on the complete orf-x nucleotide sequences seems to highlight the presence of three distinct groups statistically well supported by bootstrapping: i) exogenous JSRV sequence from the UK; ii) exogenous JSRV sequences from Southern Europe and iii) the exogenous South African strain plus all the endogenous sequences analyzed and collected from Australia, Italy, UK and South Africa.

Animals↗
PubMed2000

Expression and antigenic characterization of recombinant Mycoplasma agalactiae P48 major surface protein.

The gene encoding the P48 major surface lipoprotein of M. agalactiae has been recently characterised. Since its product plays an important role in the immune response of infected animals, in this study we analysed a recombinant P48 expressed in E. coli. Multiple point mutations were introduced by site directed mutagenesis in order to convert four tryptophan TGA codons, which are a typical feature of the mycoplasma genetic code, into the standard TGG. The mutated p48 gene was subcloned into pGex-2T and expressed in fusion with glutathione-S transferase. Following purification steps, P48 was eluted from carrier protein by thrombin digestion and used in Western blot and indirect ELISA using well-characterised sheep sera. Results demonstrate that specific antibodies against P48 are detected 3 weeks after onset of clinical disease and the recombinant P48 is a diagnostically relevant marker of M. agalactiae infection.

Animals↗
PubMed2000

Paratuberculosis in red deer (Cervus elaphus hippelaphus) in the western Alps.

During the hunting seasons 1995-96 to 1997-98, 19 red deer from the Upper Susa Valley (Cottian Alps) were examined for paratuberculosis (Johne's disease). Specific DNA amplification on mesenteric lymph nodes detected Mycobacterium avium paratuberculosis in 17 animals. Ten of these red deer were tested for serum antibodies by the AGID and ELISA tests, nine being negative. Three isolates from infected deer were genetically characterized by an arbitrarily primed polymerase chain reaction, and showed similar genetic polymorphism to that of bovine strains isolated in different Italian areas. The study showed that paratuberculosis is present in red deer of the Upper Susa Valley and that serological tests are not an efficient means for monitoring this infection.

Animals↗
PubMed2000

Mycobacterium paratuberculosis infection in two free-ranging Alpine ibex.

The authors report two cases of Mycobacterium paratuberculosis infection in free-ranging Alpine ibex (Capra ibex) from two different herds in the Western Alps, Italy. One ibex, found dead in October 1998, was in poor condition. The second animal died due to trauma following capture with a dart gun. The only gross lesions observed were the enlargement of the mesenteric and iliac lymph nodes. Samples from both ibex tested positive to polymerase chain reaction for a primer set specific for the M. paratuberculosis insertion sequence IS900 and one ibex also tested positive to the Zielh-Nielsen stain. Isolation by bacterial culture was not successful. The infected ibex originated from herds in which seroreactors to M. paratuberculosis had been found previously. Seroreactors to M. paratuberculosis were also detected in sympatric cattle.

Animals↗
PubMed1999

Characterization of the immunodominant cross-reacting epitope of visna maedi virus and caprine arthritis-encephalitis virus capsid antigen.

Maedi visna (MV) and caprine arthritis-encephalitis (CAE) are two retroviral infections distributed world wide. Antigenic cross reactions between the viruses have been demonstrated in gag and env encoded structural proteins. Antigens from ovine lentiviruses are easier to produce in cell culture systems and therefore have been used in the development of diagnostic tests for both infections. Antigenically relevant epitopes have been characterised in the transmembrane protein, but little information is available on the immunodominant and cross reacting epitopes in the major capsid antigen (p25). In this study four different recombinant subunits of ovine lentivirus p25 were tested against sera from infected goats and a detailed characterisation of the immunodominant subunit was carried out. Highest ELISA absorbances were obtained with a 29 amino acid subunit located in the N'-terminal half of p25. Through the analysis of overlapping peptides spanning this region we identified a 17 amino acid sequence that can be used in the development of a highly standardized synthetic peptide-based assay.

Amino Acid Sequence↗
PubMed1999

Low risk of Lyme borreliosis in a protected area on the Tyrrhenian coast, in central Italy.

A comprehensive Lyme borreliosis risk assessment process was applied in S. Rossore Estate, on the Tyrrhenian coast, near Pisa, Italy. Host-seeking Ixodes ricinus nymphs peaked in May in oak-dominated deciduous wood (median, Q1-Q3, number of nymphs/50 m dragging = 4.5, 2.5-8), whereas host-seeking larvae peaked in August in the same habitat type (6.0, 4-17/50 m dragging). Prevalence of I. ricinus infestation was 88.9% in wild rodents (n = 11), 64.3% in fallow deer (n = 28) and 0.0% in wild boars (n = 5). Borrelia burgdorferi sensu lato was not isolated from rodents' organs, and from 80 I. ricinus nymphs and 50 adults. Moreover, PCR for B. burgdorferi sl carried out on 110 nymphs and 12 adult ticks also gave negative results. Forest workers were at higher risk of tick bite than other Estate employees (relative risk (RR): 1.7, p = 0.02). In spite of high levels of tick exposure, B. burgdorferi sl specific antibodies were not detected in sera from Estate personnel (n = 30) and sentinel animals (dogs, n = 23, fallow deer, n = 61).

Animals↗
PubMed1999

P48 major surface antigen of Mycoplasma agalactiae is homologous to a malp product of Mycoplasma fermentans and belongs to a selected family of bacterial lipoproteins.

A major surface antigenic lipoprotein of Mycoplasma agalactiae, promptly recognized by the host's immune system, was characterized. The mature product, P48, showed significant similarity and shared conserved amino acid motifs with lipoproteins or predicted lipoproteins from Mycoplasma fermentans, Mycoplasma hyorhinis, relapsing fever Borrelia spp., Bacillus subtilis, and Treponema pallidum.

Amino Acid Motifs↗
PubMed1996

Recognition of ovine lentivirus gag gene products by serum from infected sheep.

In order to localize the immunodominant regions, 12 ovine lentivirus (OLV) gag-coding gene fragments were cloned and expressed in Escherichia coli and then tested in a Western blot (WB) assay against a panel of sera collected from US and Italian OLV-infected sheep. The most immunoreactive regions were mapped to the amino-terminal of p25 and carboxyl-terminal of p14. In addition, we found that the reactivity pattern between US and Italian sheep was very similar, suggesting the antigenic domain between US and Italian isolates in the gag gene structures could be conserved. Given the broad immunoreactivity of the amino-terminal of p25, this region could serve as an ideal diagnostic antigen for the serological identification of OLV-infected sheep.

Animals↗
PubMed1996

Characterization of enzootic nasal tumor virus capsid antigen.

The RT-PCR was carried out on tumor tissue from sheep with enzootic nasal tumor (ENT), using primers designed from conserved amino acid regions of related type D retroviruses. A 591 bp PCR fragment, corresponding to 90% of the capsid antigen was cloned, sequenced and expressed in E. coli. Alignment with ovine pulmonary carcinoma (OPC) virus showed 93% nucleotide and 96% amino acid homology. No amplification occurred when DNA from ovine fetal cell line was used as template. The recombinant protein, highly expressed in prokaryotic system, reacted in immunoblot with mouse antiserum to Mason Pfizer monkey virus (MPMV) p27, as well as sera from OPC and ENT diseased animals. Preliminary application of this antigen in ELISA suggested its potential use to detect seropositive animals in infected flocks.

Animals↗
PubMed1996

Refractory cytopenia with multilineage dysplasia: further characterization of an 'unclassifiable' myelodysplastic syndrome.

Myelodysplastic syndromes (MDS) characterized by multilineage cytopenias and dysplasia but lacking an increase in blasts, with no Auer rods or monocytosis, do not exactly fit any of the categories of the French-American-British (FAB) classification of MDS and are often diagnosed as refractory anemia (RA), refractory anemia with ringed sideroblasts (RARS), or 'unclassifiable' MDS. It has been suggested that these 'unclassifiable' cases form a distinct subset with a clinical behavior more like that of refractory anemia with excess of blasts (RAEB) than that of RA or RARS, but few studies have been undertaken that characterize this group. We compared the clinical, hematologic, morphologic and cytogenetic features of 18 such patients - for whose disease we propose the designation 'refractory cytopenia with multilineage dysplasia' (RCMD) - to those of 42 patients meeting the FAB criteria for RA or RARS (14 patients) and RAEB (28 patients). Our results show that cytopenias in RCMD are more severe than those in RA or RARS, but are similar to those in RAEB. Erythroid hyperplasia and dyserythropoiesis are the main findings in bone marrow specimens of RA or RARS, but the major features in RCMD are multilineage proliferation and dysplasia, which, except for the lack of increased blasts resemble the findings in RAEB. Only 1/14 patients (7%) with RA or RARS had an abnormal karyotype, whereas RCMD resembled RAEB in terms of the frequency (41 vs 50%, respectively) and type of karyotypic lesions. Abnormalities of chromosomes 5 and 7 (excluding del(5q) as an isolated finding) or complex aberrations were seen only in RCMD and RAEB. in RCMD, the median survival was 24 months, with a 4-year survival rate of48 +/- 13%, intermediate between the findings in RA/RARS (107 months and 77 +/- 12%, respectively) and RAEB (18 months and 27 +/- 9%, respectively). Our data indicate that RCMD is a distinct subset of MDS, with an unfavorable clinical outcome. The designation 'refractory cytopenia with multilineage dysplasia' emphasizes the differences between such cases and the primarily dyserythropoietic, indolent subgroups of MDS, such as RA or RARS.

Adult↗
PubMed1995

Characterization of ovine lentivirus envelope glycoprotein expressed in Escherichia coli cell and baculovirus systems.

The ovine lentivirus (OLV) envelope protein NH2- and COOH-terminal subunits gp70 and the NH2-terminal subunit gp40 were expressed in Escherichia coli cell. The entire gp70 envelope protein was also expressed in insect cells by the recombinant baculovirus. Guinea pigs were immunized with each bacterially expressed recombinant protein, and a serum neutralization assay was used to determine their capacity to neutralize OLV. These results showed that the major neutralization epitopes are located in the NH2-terminal half of the gp70. The baculovirus expressed gp70 was found on the surface of insect cells and was immunobiologically active. Virus neutralization activity was also produced in sheep immunized with the baculovirus expressed recombinant protein.

Animals↗
PubMed1995

Comparison of ovine lentivirus detection by conventional and recombinant serological methods.

Recombinant (r) transmembrane protein (TM), major capsid protein P25, and matrix protein P16 of ovine lentivirus (OLV) were used as solid phase antigens in enzyme-linked immunosorbent assays (ELISAs) for the detection of specific antibodies against OLV in sheep sera. Sensitivity, specificity, and agreement of these three recombinant assays were compared with each other and with two currently available conventional OLV serological assays, the agar gel immunodiffusion (AGID) test and a whole-virus (WV) ELISA. Field sera from a total of 412 Midwestern United States sheep were tested and compared by the five OLV detection methods, including visibly healthy sheep selected for public sale (Group A, n = 171), samples from a breeding flock of Finnsheep and Finn-cross ewes (Group B, n = 184) and moribund sheep with clinical signs associated with OLV (Group C, n = 57). The rTM ELISA was the most sensitive OLV detection assay, both overall and within each group. Sera from 48.1% (198/412) of field samples were rTM ELISA positive. By contrast, positive rates for the rP25, rP16, and WV ELISAs and AGID test were 34.2%, 32.3%, 36.9%, and 26.9%, respectively. The rTM ELISA reactivity was 36.8% for Group A sera, 50.0% for Group B sera, and 75.4% for Group C sera. Among the 21 Group C sheep possessing OLV lung lesions at necropsy, 20 (95.2%) were rTM ELISA positive. The greatest test agreement occurred between the rP25 and the rP16 ELISAs. The data suggest that the recombinant TM immunoassay is the most accurate and sensitive of the five methods evaluated for the detection of serum anti-OLV antibodies in sheep, both at the subclinical infection and overt clinical disease stages.

Aging↗