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S Rosati

Publications and source records attributed to S Rosati.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of four diagnostic tests for the identification of serum antibodies in small ruminants infected with Mycoplasma agalactiae.

AIM: To determine the diagnostic capability of a newly developed Western blot (WB) assay for the detection of serum antibodies against Mycoplasma agalactiae compared with conventional serological tests, and to identify the best test for routine diagnostic use. METHODS: The serological test methods used were: two commercial indirect enzyme-linked immunosorbent assays (ELISA), viz ELISA-1, using a bacterial antigen preparation, and ELISA-2, using a recombinant protein (lipoprotein p48) antigen; the complement fixation test (CFT); and a newly developed WB assay, the latter both using a bacterial antigen preparation. Thirty sera from goats infected with M. agalactiae and 97 sera from non-infected sheep were tested using all four methods. RESULTS: Staining patterns in the WB were quite variable. An immuno-dominant band of 41 kDa was detected in 63% of sera from infected animals. The same band also appeared, although mostly very weakly, in 10% of sera from non-infected animals. When suspicious or very weak reactors were omitted, the diagnostic sensitivity (DSE) and diagnostic specificity (DSP), respectively, for the four assays were: WB=56.7%, 97.9%; ELISA-1=76.7%, 99.0%; ELISA-2=56.7%, 100%; and CFT=40.0%, 94.8%. CONCLUSIONS: ELISA-1 performed best in this comparison. While the WB can be used, it did not have a technical advantage over the ELISA. The CFT should be discouraged as the primary screening method for contagious agalactia and should be replaced by ELISA-1. Results from this study confirm that serological test methods for contagious agalactia are useful for the detection of infected flocks but will not detect every individual infected animal.

Animals↗
PubMed2005

Genetic and antigenic characterization of the matrix protein of two genetically distinct ovine lentiviruses.

Small Ruminant Lentiviruses (SRLV) are a group of non-oncogenic retroviruses including Maedi-Visna virus (MVV) and Caprine Arthritis-Encephalitis virus (CAEV), which cause a chronic, multisystemic disease in sheep and goats, respectively. Phylogenetic analyses of SRLV are based in most cases on partial pol sequences. Several reports indicate that the species specificity of these viruses is not as strict as previously thought; MVV-like viruses have been found in goat populations and vice versa. Recently, the sequencing of some Italian ovine isolates has shown the presence of a new cluster more similar to classical caprine isolates (CAEV-like). Few data are available on the variability of structural proteins involved in the antibody response of infected animals. In this study, the gag gene of two genetically distinct ovine isolates, namely the MVV-like It-561 and the CAEV-like It-Pi1, was sequenced and the epitopes of matrix protein (MA) were mapped. Recombinant MAs and their subunits from both ovine aforementioned strains were tested against a panel of sheep and goat sera. Reactive epitopes were found in all three subunits of MA, although the central subunit displayed a more consistent reactivity. Epitope mapping of this subunit demonstrated that the amino acid sequence of at least one immunodominant epitope was quite different in the two strains. This antigenic variability may affect the sensitivity of a single strain-based immunoassay and suggests that both SRLV genotypes should be used in the development of future diagnostic tests, to avoid viral strain selection during the eradication programmes.

Amino Acid Sequence↗
PubMed2005

Development of recombinant chimeric antigen expressing immunodominant B epitopes of Leishmania infantum for serodiagnosis of visceral leishmaniasis.

Wild canids and domestic dogs are the main reservoir of zoonotic visceral leishmaniasis (VL) caused by Leishmania infantum (syn.: Leishmania chagasi). Serological diagnosis of VL is therefore important in both human and dog leishmaniasis from a clinical and epidemiological point of view. Routine diagnosis of VL is traditionally carried out by immunofluorescent antibody test (IFAT), which is laborious and difficult to standardize and to interpret. In the last decade, however, several specific antigens of Leishmania infantum have been characterized, allowing the development of a recombinant-based immunoassay. Among them, the whole open reading frame encoding K9 antigen, the gene fragment encoding the repetitive sequence of K26, and the 3'-terminal gene fragment of the kinesin-related protein (K39sub) were previously evaluated as diagnostic markers for canine leishmaniasis and proved to be independent in their antibody reactivity. Since sensitivity of serological test is usually higher in multiple-epitope format, in this study the relevant epitopes of K9, K26, and K39 antigens were joined by PCR strategy to produce the chimeric recombinant protein. The resulting mosaic antigen was found highly expressed in Escherichia coli and efficiently purified by affinity chromatography. Antigenic properties of this recombinant antigen were evaluated by indirect enzyme-linked immunosorbent assay (ELISA) using a panel of human and dog sera previously characterized by parasitological and/or serological techniques. Chimeric ELISA showed 99% specificity in both human (n = 180) and canine (n = 343) control groups, while sensitivity was higher in canine VL (96%, n = 213) than in human VL (82%, n = 185). Accordingly, concordance between IFAT and canine chimeric ELISA (k = 0.95, 95% confidence interval = 0.93 to 0.98) was higher than between IFAT and human chimeric ELISA (k = 0.81, 95% confidence interval = 0.76 to 0.87). Results suggest the potential use of this new antigen for routine serodiagnosis of VL in both human and canine hosts.

Adult↗
PubMed2005

Bcl-xl expression in multiple myeloma.

In the present study the immunohistochemical expression of Bcl-xl, a downstream target of the IL-6-controlled signal transducer and activator of transcription-3 (Stat3) was studied in 40 multiple myeloma (MM) cases before treatment and 11 MM patients at relapse. Correlation analysis was performed between Bcl-xl expression, C-reactive protein (CRP) level, beta-2-microglobulin (beta2m), microvessel density (MVD), and clinical outcome. Before treatment 28 (70%) patients demonstrated a Bcl-xl expression similar to normal plasma cells ("normal pattern"), while 12 (30%) patients demonstrated an elevated expression in a subgroup of the malignant plasma cells. At relapse, no change in Bcl-xl expression was observed as compared to pretreatment sample. No correlation was observed between the Bcl-xl expression and the level of CRP and b2m. In addition, no significant correlation was observed between the Bcl-xl expression and the MVD, but MVD was significantly increased as compared to normal bone marrow biopsy specimens (p=0.02). Patients with an elevated or normal Bcl-xl expression showed no statistically significant difference in overall and event-free survival. In summary, these data indicate that Bcl-xl is elevated in a subgroup of MM patients that so far did not correlate with CRP, b2m, MVD, and clinical outcome.

Aged↗
PubMed2005

Initial cytomegalovirus prophylaxis with ganciclovir: no guarantee for prevention of late serious manifestations of CMV after solid organ transplantation.

A 37-year-old woman presented with malaise, upper abdominal pain and fever seven months after renal transplantation. She was seronegative for cytomegalovirus (CMV) and had received a kidney from a seropositive donor. She had received CMV prophylaxis (oral ganciclovir) for three months after transplantation. During this period all tests for CMV remained negative. On admission, she presented with symptoms compatible with an acute abdomen and with deterioration of renal function. On emergency laparotomy a perforation of the ileum was found. The resected specimen showed an ulcer with vasculitis at the site of perforation, with both microscopic (owl's eye inclusion bodies), as well as immunohistochemical evidence for a CMV infection. CMV can reactivate (usually in the first three months) after transplantation, sometimes resulting in serious morbidity. The use of antiviral prophylaxis during and after transplantation has certainly decreased the number and severity of CMV infections. This case illustrates that life-threatening infections such as CMV can still emerge a long time after transplantation. Unrelenting awareness of this condition is mandatory, even after apparently adequate anti-CMV prophylaxis.

Adult↗
PubMed2005

Chronic lymphocytic leukaemia: a review of the immuno-architecture.

Immunophenotyping of B cell chronic lymphocytic leukaemia (B-CLL) is usually performed by flow cytometry on cell suspensions obtained from peripheral blood, bone marrow or biopsied tissue. Immunohistochemical analysis on routine sections is less commonly performed; however, this approach allows the pathologist and the researcher to appreciate the immuno-architecture of the involved tissues and to gain insight into some of the events that influence the biology of the disease. In this review the authors focus on the following issues: immuno-architecture of the proliferation centres, expression of CD23, MUM1/IRF-4 and cyclin D1, tyrosine phosphorylation and detection of the ZAP-70 kinase. Whenever possible, an attempt is made to interpret the immunohistochemical findings from a functional point of view.

Cell Proliferation↗
PubMed2005

Fungicide residues in pears, apples and grapes after post harvest treatments by thermonebulization.

In the context of trials conducted in cold store, in order to investigate efficacy of fruit protection applying agrochemicals, the fate during the storage of two active ingredients (a.i.): pyrimethanil and imazalil, have been studied. The experimental trials were done on eight varieties of apples and pears and two of grapes. Only field use of named pesticides was already authorised on fruits and maximum residue limits (MRL) fixed. In the present biennial experimentation (apples and pears in the first year; grapes in the second one). Two fungicides formulations were applied and treatments have been executed by thermonebulization technique. The storage cell, had a volume of 110 m3 filled up with the fruits until 80% of its capacity. Each fruit variety constituted one thesis of 4 replicates. For each trial, only one treatment was performed at the beginning of conservation period (72 days for pears and apples, and 57 days for grapes). In order to estimate fungicides persistence, residues determinations have been carried out. From results obtained especially on grape, not homogenous residues distribution on treated commodities was observed. For all theses, residue level has not evidenced statistically significant decrement as function of time, behaviour not as observed in field tests. The following average values of residues have been determined: in apples and pears, 0.7 mg/kg of imazalil much lower than 5 mg/kg (RML fixed for field use), and 1.2 mg/kg of pyrimethanil little higher than 1 mg/kg (RML fixed for field use); in grapes 0.5 mg/kg pyrimethanil much lower than 3 mg/kg (RML fixed for field use).

Consumer Product Safety↗
PubMed2004

Development of recombinant capsid antigen/transmembrane epitope fusion proteins for serological diagnosis of animal lentivirus infections.

Among animal lentiviruses, Feline immunodeficiency virus (FIV), Equine infectious anaemia virus (EIAV) and Small ruminant lentiviruses (SRLV) are important pathogens associated with a variety of clinical pictures including immunodeficiency, anaemia, arthritis, pneumonia. The detection of viral antibody response represents a practical diagnostic approach in all lentivirus infections since they remain detectable long life. Capsid antigen (CA) is the major viral core protein and specific antibodies against this antigen are usually first recognised in infected sheep, goat and horse, remaining detectable for long period. Transmembrane (TM) domain of envelope glycoprotein contains a well conserved motif known to form an immunodominant epitope in several lentiviruses. In this study a simple strategy was developed to express the entire CA and the TM epitope in a single fusion protein from equine, feline and small ruminant lentiviruses in prokaryotic system and evaluated the diagnostic utility of a purified preparation in an indirect ELISA for each of the three infections. Results demonstrate that, for FIV and SRLV infections, the combination of CA and TM fractions increases the sensitivity of diagnostic tests based only on CA. The corresponding CA/TM antigen from EIAV showed excellent agreement with Coggins test.

Amino Acid Motifs↗
PubMed2004

A multiplex PCR assay for the identification of animal species in feedstuffs.

A multiplex Polymerase Chain Reaction (PCR) assay was applied to feedstuff analysis for the identification of the most used species in rendering plants (ruminant, poultry, fish and pork materials). Primers were designed in different regions of mitochondrial DNA (12S rRNA, tRNA Val and 16S rRNA) after alignment of the available sequences in the GenBank database. The primers generated specific fragments of 104-106, 183, 220-230 and 290 bp length for ruminants, poultry, fish and pork, respectively. The detection limit was 0.004% for fish primers and 0.002% for ruminants, poultry and pork primers. The multiplex PCR proposed in this study can be considered a valid alternative to the microscopic method for the detection of animal derived materials banned by a European Union Regulation as a preventive measure against the spread of Bovine Spongiform Encephalopathy.

Animal Feed↗
PubMed2004

Development of a multiplex PCR assay for the identification of pathogenic genes of Escherichia coli in milk and milk products.

A multiplex PCR for the simultaneous detection of some pathogenic genes of enteropathogenic, enterotoxigenic and verocytotoxin-producing Escherichia coli was developed. In this study primers found in literature as well as primers to the purpose designed were used. In this way, it was possible to generate specific fragments of 96, 170, 229, 285, 348, 414 and 510 bp for Hlya, St, EaeA, Lt, Vt1, UidA and Vt2 genes, respectively. When applied to bacterial strains experimentally inoculated in milk and milk products, the proposed PCR showed a detection limit of 5 x 10(4)CFU/ml for Hyla, St, Eaea, Vt1 primers, while for Lt and Vt2 primers the limit resulted of 10(6)CFU/ml.

Animals↗
PubMed2004

[Guidelines for the management of HCV infection in HIV-infected patients. Istituto Nazionale per le Malattie Infettive Lazzaro Spallanzani].

It is crucial to ensure an optimal clinical management of HCV infection in HIV-co-infected persons. The reasons for the development of guidelines on HCV-infection treatment in HIV-infected persons arise from the need for a standardised management of HIV/HCV coinfection in our Institute. The aim of these guidelines are: to clarify principles of clinical management of HCV infection in HIV-infected patients to care-providers; to improve the awareness of HIV-infected patients cared for our Institute on current management of HCV infection; to improve the quality of care on this topic. These guidelines, based on Evidence based Medicine principles, have been developed by a panel of experts, who conducted a systematic review of the literature, mainly taking into account current international recommendations. In the present document, the most frequent clinical presentation occurring in the management of HIV/HCV co-infected patients at our Institution are discussed. The adherence to present guidelines and their effectiveness at our Institution, outcome indicators will be evaluated. The present guidelines cannot entirely substitute the judgement of an expert clinician. However, adherence to these guidelines will contribute to the improvement of the standard of care of HIV/HCV-co-infected persons.

Anti-HIV Agents↗
PubMed2003

Health status of a population of nutria (Myocastor coypus) living in a protected area in Italy.

Ninety trapped nutria (Myocastor coypus) from a protected area of Piedmont (Italy), including the Po river, were examined for the prevalence for lesions in major viscera, selected serum antibodies and enteric bacteria. Coccidial lesions in the liver included cholangitis, calcification and necrosis. Renal lesions were nonsuppurative interstitial nephritis and a single case of renal adenocarcinoma. The lungs had a 41.1% prevalence of nonsuppurative interstitial pneumonia. Ten of 87 sera (11.5%) had antibodies against Leptospira bratislava, 3 of 87 (3.4%) against Leptospira ichterohaemorrhagiae, 15 of 41 (36.6%) against Toxoplasma gondii, and antibodies against encephalomyocarditis virus were detected in 5 of 78 sera (6.4%). All fecal samples were negative for Salmonella, Shigella, and Pseudomonas, and growth of enterobacteriaceae was in the normal range.

Animals↗
PubMed2003

Acarological risk of exposure to agents of tick-borne zoonoses in the first recognized Italian focus of Lyme borreliosis.

Acarological risk was calculated as the probability of encountering at least one host-seeking Ixodes ricinus tick infected by the pathogen Borrelia burgdorferi sensu lato, in 100 m transects in the province of Genoa, Italy. The seasonal pattern of I. ricinus was studied using generalized estimating equations (GEE) with negative binomial error, to consider overdispersion of tick counts and repeated sampling of the same dragging sites from April 1998 to March 1999. Prevalence of infection by B. burgdorferi s.l. was evaluated by PCR and hybridization with genospecies-specific probes. Acarological risk (R) peaked in April (R = 0.2, 95% CI 0.13-0.26) and November (R = 0.29, 95% CI 0.10-0.46). Borrelia garinii and B. valaisiana were the most common genospecies at our study site suggesting a major role of birds as reservoirs. DNA from Anaplasma phagocytophilum, the agent of granulocytic ehrlichiosis in humans and animals, was amplified from an adult I. ricinus.

Anaplasma↗
PubMed2003

Prokaryotic expression and antigenic characterization of three recombinant Leishmania antigens for serological diagnosis of canine leishmaniasis.

Three recombinant antigens of Leishmania chagasi (= L. infantum) were expressed in prokaryotic systems and evaluated (using a panel of dog sera characterized by parasitological and serological immunofluorescent antibody test [IFAT] techniques) as diagnostic markers of infection. The whole open reading frame encoding K9, the gene fragment encoding the repetitive sequence of K26, and the 3'-terminal gene fragment encoding a single 39-amino-acid subunit of the kinesin-related protein K39 (K39sub) were amplified from L. infantum DNA and cloned into a pGEX-2T expression vector in frame with glutathione S-transferase (GST). The sensitivity and specificity of enzyme-linked immunosorbent assays (ELISAs) using K26 as an antigen (evaluated with sera from 20 parasitologically positive and 20 parasitologically negative dogs) were both 100% (95% confidence interval [CI] = 83.2 to 100). When K9 and K39sub were used, sensitivity was 95% (95% CI = 75.1 to 99.9) and specificity was 100% (95% CI = 83.2 to 100). Using 182 field sera, a good agreement was found between the recombinant K26 ELISA and IFAT (K = 0.92; 95% CI = 0.86 to 0.98) results and between the K9 and K39sub ELISA (used in parallel) and IFAT (K = 0.87; 95% CI = 0.80 to 0.95) results. The results demonstrate that each antigen carries immunodominant epitopes and that their combination may further increase the sensitivity of currently available serological tests.

Animals↗
PubMed2003

Development of a PCR assay for the detection of animal tissues in ruminant feeds.

The European Community ban on use of meat and bone meal in ruminant feed, as a consequence of the spread of bovine spongiform encephalopathy in Europe, has prompted a number of investigations about the possibility of detecting animal tissues in feedstuff. In this paper, a study on vertebrate primers, designed in the 16S rRNA gene of mitochondrial DNA, is described. These primers were able to amplify fragments that contained between 234 and 265 bp. The fragments were specific for bovine, porcine, goat, sheep, horse, rabbit, chicken, trout, and European pilchard and were confirmed by sequence analysis amplicons. The primers were used in a PCR assay applied to five samples of meat and blood meals of different species and subjected to severe rendering treatments (134.4 to 141.9 degrees C and 3.03 to 4.03 bar for 24 min). The presence of vertebrate tissues was detected in all samples. The assay proved to be rapid and sensitive (detection limit 0.0625%). It can be used as a routine method to detect animal-derived ingredients in animal feedstuff.

Animal Feed↗