Biomedical subjects

M Amadori

Publications and source records attributed to M Amadori.

At least 19 recordsLinked to original sources

PubMed2005

Low-dose interferon-alpha treatment for feline immunodeficiency virus infection.

Feline immunodeficiency virus sustains an AIDS-like syndrome in cats, which is considered a relevant model for human AIDS. Under precise enrolment requirements, 30 naturally infected cats showing overt disease were included in a trial of low-dose, oral human interferon-alpha treatment. Twenty-four of them received 10 IU/Kg of human interferon-alpha and 6 placebo only on a daily basis under veterinary supervision. The low-dose human interferon-alpha treatment significantly prolonged the survival of virus-infected cats (p<0.01) and brought to a rapid improvement of disease conditions in the infected hosts. Amelioration of clinical conditions was neither correlated with plasma viremia, nor with proviral load in leukocytes. A good survival of CD4+ T cells and a slow increase of CD8+ T cells were also observed in human interferon-alpha-treated cats. Interestingly, the improvement of the total leukocyte counts showed a much stronger correlation with the recovery from serious opportunistic infections. As shown in other models of low-dose interferon-alpha treatment, there was a rapid regression of overt immunopathological conditions in virus-infected cats. This hints at a major role of interferon-alpha in the control circuits of inflammatory cytokines, which was probably the very foundation of the improved clinical score and survival despite the unabated persistence of virus and virus-infected cells.

Animals↗

PubMed2004

Application of universal primers for identification of Foot-and-mouth disease virus and Swine vesicular disease virus by PCR and PCR-ELISA.

Two approaches for simultaneous identification of both Foot-and-mouth disease virus (FMDV) and Swine vesicular disease virus (SVDV) are described: (1) a single-step reverse transcription-PCR with three primers and (2) a PCR-ELISA assay with two universal primers for genome amplification and two virus-specific probes for identification. These methods are based on the use of 3D gene universal PCR primers, the structure of which was optimized and refined due to the close relationship between the two viruses belonging to different genera of the Picornaviridae family. In procedure (1), a three-primer PCR containing one universal antisense primer and two virus-specific primers was shown to differentiate between FMDV and SVDV in one reaction, due to the different length of the amplified DNA fragments (600 and 340 base pairs, respectively). In procedure (2), the two viruses were identified by PCR-ELISA, i.e. PCR for the 3D gene followed by two parallel hybridizations with FMDV and SVDV-specific probes in microplate wells and ELISA detection. The application of universal primers could halve the number of PCR experiments in both cases, as compared to the usual virus-specific PCR procedures. Also, we investigated the 3D gene structure of several SVDV strains isolated at different times. No essential changes were detected in the regions coding for conserved motifs of the RNA-dependent RNA polymerase recognized by our universal primers. The multi-primer PCR was successfully tested on 38 FMDV and 15 SVDV strains, and the PCR-ELISA on 32 FMDV and 16 SVDV strains including clinical material from disease cases.

Amino Acid Motifs↗

PubMed2003

Use of a macrophage cell line for rapid detection of Mycobacterium bovis in diagnostic samples.

Mycobacterium bovis isolation on bacteriological media from suspected cases of bovine tuberculosis (TB) demands laborious and time-consuming procedures. Even polymerase chain reaction (PCR) and radiometric analyses are secondary procedures and not alternatives to bacteriological procedures. Therefore, there is a need to develop new techniques aimed at rapid M. bovis detection in diagnostic samples. The human macrophage cell line THP-1 was thus investigated in experiments of M. bovis propagation and isolation from reference lymph node suspensions. THP-1 cells were shown to support a high-titered propagation within 48h of minute amounts of both M. bovis BCG and fully pathogenic M. bovis strain 503. A semi-nested PCR for TB-complex-specific insertion sequence IS6110 revealed M. bovis infection in THP-1 cells. The same was true of a flow cytometry (FC) assay for expression of M. bovis chaperonin 10 in infected cells. The reduced time for isolation and identification of M. bovis (48-72h) and the consistency of the test results make the use of macrophage cell cultures attractive and cost-effective for veterinary laboratories involved in TB surveillance.

Animals↗

PubMed2002

Diagnosis of Mycobacterium bovis infection in calves sensitized by mycobacteria of the avium/intracellulare group.

Because of the frequent exposure of cattle to mycobacteria of the avium/intracellulare group, an investigation was carried out into the possible repercussions thereof on the diagnosis of bovine tuberculosis. Three calves from a bovine tuberculosis-free herd, scored avian reactors in the gamma-interferon assay for bovine tuberculosis, were sedated and inoculated endotracheally with a virulent Mycobacterium bovis strain. Then, three other avian reactors were housed with the above donor calves. Mycobacterium bovis was isolated from the nasal swabs of the three endotracheally infected, donor calves. On these samples, TB complex-specific polymerase chain reaction (PCR) tests for IS6110 were also positive, albeit with a different time kinetics. The three contact-infected calves showed clear immunological signs of infection; however, their nasal swabs were always PCR-negative and only Mycobacterium avium was isolated. In the endotracheally infected donor calves there was a rise of the gamma-interferon responses to avian and bovine purified protein derivative (PPD) tuberculins, which reached the same stable plateau levels over the whole experiment. The above effect was also observed in the contact-infected calves, even though the response to avian PPD tuberculin always remained at a higher level. By using conventional bovine and avian PPD tuberculins, the comparative intradermal test was generally positive in endotracheally infected, as opposed to contact-infected calves; a positive intradermal test for M. bovis was obtained in two contact-infected calves by different bovine PPD tuberculins based on M. bovis bacillus Calmette-Guerin (BCG) secreted or somatic antigens. It was concluded that M. bovis infection may be concealed for some time in cattle sensitized by mycobacteria of the avium/intracellulare group and that different diagnostic procedures should be adopted for such animals.

Animals↗

PubMed2000

Effect of long-term oral administration of an immunostimulant diet on innate immunity in sea bass (Dicentrarchus labrax).

Immunostimulants represent a modern and promising tool in aquaculture, enhancing the resistance of cultured fish to disease and stress. This study investigated the effect of a combination of dietary glucans, alpha-tocopherol and ascorbic acid on the innate immune response of cultured sea bass (Dicentrarchus labrax). After 5 weeks of adaptation on a commercial diet containing 100 p.p.m. ascorbic acid and 200 p.p.m. alpha-tocopherol, sea bass were switched to a diet supplemented with 2% beta-1.3/beta-1.6 glucans and ascorbic acid and alpha-tocopherol at 500 p.p.m. The supplemented diet was given at 2% of body weight per day over a 2-week period, every 3 months. Plasma lysozyme concentration, content and distribution of major plasma proteins and complement activity were measured prior to feeding the supplemented diet and after 40 weeks. Alternative pathways of complement activation and lysozyme activity were both significantly enhanced in fish fed on glucans and elevated doses of vitamins. No significant differences were observed in protein content or in albumin/globulin ratio. Compared to lysozyme activity, which showed marked individual variation, complement-mediated haemolytic activity has been shown to be a more reliable indicator of sea bass immunocompetence. Further studies are in progress to clarify the effect of each dietary component on the innate immune response and disease resistance.

Adjuvants, Immunologic↗

PubMed2000

Evaluation of the specificity of the gamma-interferon test in Italian bovine tuberculosis-free herds.

We investigated the specificity of the gamma-interferon test for bovine tuberculosis (TB) in 1,557 cattle in 30 paratuberculosis-free and officially certified TB-free dairy herds, located in three provinces of the Lombardy Region in Northern Italy. The TB-free status of the herds under examination was further confirmed by the tuberculin skin test, by an antibody assay and by post mortem examination of animals culled from the herds during the study period. The specificity of the gamma-interferon tests after a single test and a double sampling scheme were 88.8% and 95.4%, respectively. After a single test, 11.7% of dubious reactors were also detected, while most cattle (47.4%) were shown to be avian reactors, probably due to contamination from infected birds and/or forage. There was strong evidence that the specificity of the test could be related to the animals' interaction with environmental mycobacteria and/or ageing. To reduce the percentage of nonspecific bovine reactors under alleged TB-free conditions, test procedures might involve the use of more specific antigens and/or different reaction thresholds.

Animals↗

PubMed1999

Chaperonin 10 of Mycobacterium tuberculosis induces a protective immune response to foot-and-mouth disease virus.

Chaperonin 10 of M. tuberculosis conferred partial or total protection against generalized foot-and-mouth disease (FMD) in guinea-pigs challenged with O1 Lausanne FMD virus. Chaperonin 10-immunized animals mounted an antibody response to the protein, one epitope of which was found in the C-terminal half. A similar recognition pattern was observed in FMD-convalescent guinea-pigs, swine and cattle. Anti-chaperonin 10 sera showed antiviral activity against FMDV-infected BHK-21 cells. There was strong evidence that early after infection these cells actively secrete their histones and that antisera to the chaperonin recognize them. The same antisera reacted with purified histones in immunoblotting. Most important, exogenously added histones abrogated the anti-viral activity of the antiserum and an anti-histone monoclonal antibody had strong antiviral activity against FMDV-infected BHK-21 cells. These results are consistent with previous reports on displacement of histones from the nuclear compartment and immune recognition of self-histones after viral infections. On the whole, they indicate that M. tuberculosis chaperonin 10 enables the immune system to react against early abnormalities of virus-infected cells; this is accomplished by antibody cross-reacting with histones released during virus infection.

Amino Acid Sequence↗

PubMed1998

Quality controls and in vitro diagnostic efficiency of bovine PPD tuberculins.

Wide heterogeneity was shown among different batches of bovine protein purified derivative (PPD) tuberculin, as regards protein content and antigenic profile. These features were also investigated in pilot preparations of Mycobacterium bovis secreted antigens and PPD tuberculins. Under controlled conditions, widely different compositions were revealed as a function of the M. bovis strain and also of the time in culture, due to the transient expression of seemingly important clusters of antigens. Furthermore, these parameters could dramatically affect the efficacy of the above preparations in in vitro assays of cell-mediated immunity on M. bovis-infected cattle. The field exposure to mycobacteria of the avium/intracellular group could also influence the readout of such assays, results being in agreement with a bystander suppression model of the response to M. bovis antigens. Due to the above, practical suggestions are put forward to improve the composition of bovine PPD tuberculins and the relevant control procedures.

Animals↗

PubMed1998

Antibody tests for identification of Mycobacterium bovis-infected bovine herds.

Antibody in sera from 560 cattle of tuberculosis (TB)-infected and TB-free herds was investigated by competition and indirect enzyme-linked immunosorbent assays using bovine purified protein derivative tuberculin as the antigen. Antibody was detected in sera from both types of herd, with a widely overlapping range of titers. However, a "tail" of high-titered sera was observed for the distribution of data for only those cattle from TB-infected herds.

Animals↗

PubMed1998

[Pulmonary metastasis from an eccrine carcinoma: thoracic perfusion with the aorto-caval stop-flow technique. Description of a clinical case].

A case of a 64-year-old man with eccrine carcinoma arising from hand skin is reported. At the time of diagnosis he showed bilateral pneumonic metastases. Although the patient underwent two systemic chemotherapy lines, he showed further progressive disease of the lung. For this reason a third chemotherapy line was started through thoracic stop-flow infusion. In this way, a five month stable disease had been achieved. The patient died 7 months later for progressive disease. The rarity of this disease, the uncertain treatment, the feasibility and efficacy of thoracic stop-flow infusion are underlined and further studies are suggested.

Antineoplastic Agents↗

PubMed1997

Phenotypic features of BHK-21 cells used for production of foot-and-mouth disease vaccine.

BHK-21 c13 monolayer and suspension cells were investigated with regard to some phenotypic features which could bear on the quality of foot-and-mouth disease virus (FMDV) antigen produced in them. Despite good viability, suspension cells differed from monolayer cells in fundamental features of susceptibility to FMDV. Most important, FMD virus particles grown in suspension cells at high passage levels were shown to be largely degraded following inactivation with an aziridine compound. Suspension cells were characterised by a downregulation in the surface expression of both alpha 5 and alpha V integrin chains. According to the results of binding assays, both integrins could act as FMDV receptors on BHK-21 c13 cells. Reduced surface expression of integrins was correlated with disappearance of actin stress fibres, which would play a role in regular encapsidation of viral RNA and hence in stability of virus particles. With regard to FMD vaccine production, practical suggestions are put forward to evaluate the quality of BHK-21 c13 cells and FMDV Ag, which must prove stable during downstream processing.

Animals↗

PubMed1997

An immunological approach to the evaluation of welfare in Holstein Frisian cattle.

Clinical immunological and haematological parameters, along with clinical conditions and growth rate, were studied in 413 male Holstein Frisian calves introduced into a large centre for genetic selection in different seasons of the year. Abnormalities were revealed by the laboratory tests in the great majority of calves after transportation stress, a general tendency to the restoration of physiological values being evident thereafter. Laboratory parameters were highly correlated with disease conditions: with three exceptions only, animals showed altered laboratory parameters some days before the occurrence of clinical symptoms. Eighteen per cent of animals showed altered laboratory parameters with no obvious clinical signs of disease; yet they experienced a reduced weight gain. Results suggest that clinical immunological and haematological parameters could be the foundation of a new, large-scale, robust approach to the control of welfare in cattle, which should be integrated preferably by a further range of records and measures.

Animal Husbandry↗

PubMed1997

[Prognostic factors in breast carcinoma with negative axillary lymph nodes].

Conventionally, tumor size, axillary lymph nodes status, histologic type and grading, proliferative activity, steroid receptors have been used to predict the natural history of breast cancer. In node-negative patients with breast cancer it is most important to identify biological markers that can predict the risk of systemic relapse. These features have been used to allow selection of the best treatment. In this paper we describe the prognostic significance of new tumoral markers in breast cancer patients without axillary involvement. We analyze the prognostic role and the correlation with response to treatment of these parameters: ploidy, oncogenes, p53, epidermal growth factor receptor and cathepsin D.

Biomarkers, Tumor↗

PubMed1997

[Combined intra-arterial locoregional and systemic treatment of nonresectable hepatic metastases of colorectal carcinoma].

Intra-arterial hepatic chemotherapy (LAHC) results in significantly higher response rate than the best systemic treatment of liver metastases from colorectal cancer, but no survival advantage has to date shown because of extra-hepatic progression. From June 1991 to December 1994, twenty patients with hepatic metastases from colorectal cancer were enrolled. All patients underwent laparotomy for the placement of an intra-arterial catheter into the gastroduodenal artery connected with a subcutaneous port. All patients underwent cholecystectomy and biopsy of liver lesion to confirm metastatic disease. Locoregional schedule was: 5-fluorouracil (5FU) 500 mg/sqm, epirubicin (EPI) 13 mg/sqm, mitomycin-C (MMC) 7 mg/sqm, in bolus every 3 weeks. Systemic therapy consisted of leucovorin 500 mg/sqm, over 2 hours and 5FU 600 mg/sqm in bolus every week. Treatment was planned over a six month period. The complete response (CR) plus partial response (PR) rate was 50% of the entire group. The median survival was 18 months and 1- and 2- and 3-year survival rates were 71%, 38% and 20% respectively. Prior to chemotherapy, LDH value and % of liver involvement were the only significant prognostic parameters. Toxicity was absent or mild and no patient stopped treatment because of side effects. Combined systemic and IAHC is an effective treatment for liver metastases from colorectal cancer, with a mild or moderate toxicity. However, more trials are needed, to improve the control of the extrahepatic disease.

Adult↗

PubMed1996

[Testicular lymphomas. A clinico-pathological study of 5 cases and a review of the literature].

The authors describe five consecutive patients with testicular non Hodgkin lymphoma, evaluate the clinical and histological characteristics and underline the importance of a chemotherapy approach both at diagnosis and at relapse. A review of the literature is carried on and particularly about the prognostic factors, the correlation with Ebstein Barr virus and the more recent integrated therapeutical approaches.

Aged↗

PubMed1996

[Considerations on the rehabilitation of the hearing in cochlear implant patients].

In this study, the Cochlear Implant Programme of the ENT Department of Ospedale Civile di Venezia, is presented. Between 1989 and 1994, after a rigorous selection process, 36 patients were selected to be implanted with a cochlear prostheses: 28 with the multichannel Nucleus 22 device, 5 with the Clarion implant and 3 with the single channel Med-E1 BTE device. The distribution of the patients according to age, etiology, duration of auditory deprivation, age at onset of deafness, is presented. The different speech-coding strategies of the Nucleus system (Wearable Speech Processing, Multipeak speech processing and Spectral Maximum Sound processor) and the stimulation mode (common ground, bipolar, bipolar + 1) as well as the Clarion speech coding strategy (Continuous Interleaved Samples and Compressed Analog) are briefly discussed. The rehabilitation programme, the specific speech recognition assessment test batteries-Consonant Confusion Test, Vocal Confusion Test, Speech Tracking, MAC battery-as they are employed in our department, are presented. As we have analyzed our results, certain factors appear as predicting a favourable outcome: - age of onset of deafness; postlingual patients, who have developed communication skills compare favourably to the perilingual group. - durations of auditory deprivation, as it is related to surviving cells in the cochlea: the shorter the period of deafness, the better the results. - length of electrode insertion, as it is determined by ossification of the cochlea. - high dynamic range of the MAP. - percent of activated electrodes: a number of 10 active electrodes or less predicts a poor outcome. - for simplification reasons, a new variable is introduced-Auditory Deprivation Index- and its positive correlation to the performance presented. - the time period of experience with the device, length and quality of rehabilitation and family support have to be mentioned.

Adolescent↗

PubMed1995

Role of a distinct population of bovine gamma delta T cells in the immune response to viral agents.

A distinct population of bovine gamma delta T cells was isolated from peripheral blood mononuclear cells of foot-and-mouth disease (FMD)-vaccinated cattle; these lymphocytes were shown to exert a natural killer-like activity against cells infected by different viruses. The antiviral activity was dependent upon cognate recognition of target cells and could operate by both cytostatic and cytotoxic mechanisms. Among these, secretion of a serine esterase was shown after binding to target cells. This population of bovine gamma delta T cells is recognized by murine monoclonal antibodies 1E7, 5D4, and 6F9, raised in our laboratory. To define an in vivo antiviral role, four heifers were infected with a strain of bovid herpesvirus 1 by the intranasal/intravaginal routes and contact exposure. The prevalence of 1E7+/5D4+ cells among peripheral blood lymphocytes increased dramatically in the first days after infection; the same held true for in-contact cattle, albeit with a different time kinetics. In another experiment, colonization of mucosae was demonstrated by immunoperoxidase staining on tongue and palate sections of healthy cattle. The infiltration of gamma delta T cells altogether in the palate mucosa was much more accentuated in foot-and-mouth disease-vaccinated, as compared to nonvaccinated, control calves.

Animals↗

PubMed1995

Characterization of a distinct subpopulation of bovine gamma delta T cells.

A population of mononuclear cytotoxic cells from peripheral blood leucocytes of cattle showed no usual markers of B and T lymphocytes. However, it could be allocated to a previously unreported gamma delta T cell compartment. This assumption was suggested by: 1. The surface expression of CD3; 2. PCR amplification of the C delta TcR gene from cDNA; and 3. The detection of peripheral blood precursors expressing the workshop cluster (WC) 1 marker of bovine gamma delta T cells. These cells are recognized by murine monoclonal antibodies (mAbs) 5D4, 1E7, 6F9 and 8D7, raised in the authors' laboratory. The above mAbs also identify distinct groups of cells in thymus, spleen, lymph nodes and about 1% of uncultured PBL. The most diffuse infiltration of such cells was shown in the small intestine, as both intraepithelial and lamina propria lymphocytes. Mucosal homing activity was confirmed by immunoperoxidase staining on tongue and pharynx sections of healthy cattle.

Animals↗