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A Amadori

Publications and source records attributed to A Amadori.

At least 19 recordsLinked to original sources
PubMed2006

Continuous EEG-SEP monitoring of severely brain injured patients in NICU: methods and feasibility.

AIMS: To evaluate the feasibility of a continuous neurophysiologic monitoring (electroencephalography (EEG)-somatosensory evoked potentials (SEPs)) in the neuro-intensive care unit (NICU), taking into account both the technical and medical aspects that are specific of this environment. METHODS: We used an extension of the recording software that is routinely used in our unit of clinical neurophysiology. It performs cycles of alternate EEG and SEP recordings. Raw traces and trends are simultaneously displayed. Patient head and stimulator box are placed behind the bed and linked to the ICU monitoring terminal through optic fibers. The NICU staff has been trained to note directly clinical events, main artefacts and therapeutic changes. The hospital local area network (LAN) enables remote monitoring survey. RESULTS: Continuous EEG (CEEG)-SEP monitoring was performed in 44 patients. Problems of needle detachment were seldomly encountered, thanks to the use of a sterile plastic dressing, which covers needles. We never had infection or skin lesions due to needles or the electrical stimulator. The frequent administration of sedative at high doses prevented us from having a clinically valuable EEG in several cases but SEPs were always monitorable, independently of the level of EEG suppression. The diagnosis of seizures and non-epileptic status was based on raw EEG, while quantitative EEG (QEEG) was used to quantify ictal activity as a guide to treatment. CONCLUSIONS: EEG and EP waveforms collected in NICU were of comparable quality to routine clinical measurements and contained the same clinical information. A continuous SEP monitoring in a comatose and sedated patient in NICU is not technically more difficult and potentially less useful than in operating room. This monitoring appears to be feasible provided the observance of some requirement regarding setting, electrodes, montages, personnel integration, consulting and software.

Brain Injuries↗
PubMed2006

Gene therapy of ovarian cancer with IFN-alpha-producing fibroblasts: comparison of constitutive and inducible vectors.

Ovarian cancer represents a malignancy suitable for cell and gene therapy approaches owing to its containment within the peritoneal cavity, even at advanced tumor stages. As regulation of transgene expression would be preferable for conducting clinical trials for reasons of safety, we investigated whether intraperitoneal (i.p.) administration of retroviral vector-transduced fibroblasts encoding murine interferon-alpha (IFN-alpha) could have therapeutic activity, and compared its effect with the antitumor effects of fibroblasts producing IFN-alpha under a rapamycin analogue (AP21967)-inducible promoter. Human and murine fibroblasts were recruited into the solid component of transplantable ovarian cancer-grown i.p. in severe combined immunodeficiency mice. Multiple administrations of fibroblasts producing IFN-alpha in a constitutive manner showed therapeutic efficacy, leading to significant prolongation of survival in the majority of animals, associated with inhibition of tumor angiogenesis. Compared to cells transduced by the constitutive vector, fibroblasts transduced by the inducible vector released twofold higher IFN-alpha levels in vitro, following induction by AP21967, and production of the cytokine was under pharmacologic control both in vitro and in vivo. However, these cells elicited only modest therapeutic effects in vivo. Overall, these findings indicate that intracavitary IFN-alpha gene therapy using engineered fibroblasts requires sustained production of IFN-alpha to achieve durable antitumor effects.

Animals↗
PubMed2005

Extracellular matrix-enriched polymeric scaffolds as a substrate for hepatocyte cultures: in vitro and in vivo studies.

Tissue engineering is a promising approach to developing hepatic tissue suitable for the functional replacement of a failing liver. The aim of the present study was to investigate whether an extracellular cell matrix obtained from fibroblasts-cultured within scaffolds of hyaluronic acid (HYAFF) could influence the proliferation rate and survival of rat hepatocytes both during long-term culture and after in vivo transplantation. Cultures were evaluated by histological and morphological analysis, a proliferation assay and metabolic activity (albumin secretion). Hepatocytes cultured in extracellular matrix-enriched scaffolds exhibited a round cellular morphology and re-established cell-cell contacts, growing into aggregates of several cells along and/or among fibers in the fabric. Hepatocytes were able to secrete albumin up to 14 days in culture. In vivo results demonstrated the biocompatibility of HYAFF-11 implanted in nude mice, in which hepatocytes maintained small well-organised aggregates until the 35th day. In conclusion, the presence of a fibroblast-secreted extracellular matrix improved the biological properties of the hyaluronan scaffold, favoring the survival and morphological integrity of hepatocytes in vitro and in vivo.

Animals↗
PubMed2005

Potential of telomerase expression and activity in cervical specimens as a diagnostic tool.

AIMS: To evaluate the potential use of the immunohistochemical expression of telomerase and the measurement of its activity as diagnostic tools in the uterine cervix. METHODS: The fluorescent telomeric repeat amplification protocol (TRAP) assay was used to evaluate telomerase activity in a series of 43 cervical scrapings. Twenty five cases were cytologically classified as inflammatory, and/or metaplastic, and/or acanthotic, and 18 cases presented cell alterations compatible with mild, moderate, or severe cervical intraepithelial neoplasia (CIN). Immunohistochemistry was performed on a retrospective series of 86 archival, paraffin wax embedded blocks using a recently developed anti-hTERT (human telomerase reverse transcriptase) monoclonal antibody. RESULTS: Telomerase activity was expressed as arbitrary enzymatic units (AEU). Median values were 38.0 AEU for inflammatory non-dysplastic cell specimens, 33.5 AEU for CIN I, 41.0 AEU for CIN II, and 28.0 AEU for CIN III. The median percentage of immunoreactive dysplastic cells, as detected by immunohistochemistry, was significantly (p = 0.024) lower in CIN I (45%) than in more severe dysplastic (CIN II 70%, CIN III 80%) lesions. In contrast, no differences were seen in the enzymatic activity detected by the TRAP assay among the different dysplastic lesions. CONCLUSIONS: These data indicate that, using a molecular extra situ method, the telomerase activity of inflammatory and non-dysplastic elements masks the expected differences between mild and severe dysplasia. Conversely, an in situ approach permits the accurate identification of telomerase positive dysplastic cells.

Antibodies, Monoclonal↗
PubMed2003

Tumor outgrowth in peripheral blood mononuclear cell-injected SCID mice is not associated with early Epstein-Barr virus reactivation.

Epstein-Barr virus (EBV)-positive B-cell lymphoproliferative disease develops in severe combined immunodeficient (SCID) mice inoculated with peripheral blood mononuclear cells (PBMC) from EBV(+) individuals (SCID/hu mice). In this study, we investigated the contribution of EBV reactivation and de novo infection of B lymphocytes to tumor outgrowth in SCID/hu mice. Evaluation of BZLF-1, an early EBV activation transcript, in cells recovered from the mouse peritoneal cavity within 16 days following PBMC transfer did not reveal EBV reactivation, while BZLF-1 expression was only detected in tumor masses or in vitro established lymphoblastoid cell lines. To confirm these data by a different strategy, we coinjected PBMC from seropositive donors with purified B cells from seronegative donors of different sex. Fluorescence in situ hydridization analysis of the resulting tumor masses disclosed that the overwhelming majority of lymphoma cells originated from the seropositive donor, implying that no substantial in vivo production and transmission of virus had occurred. Further, treatment of SCID/hu mice with ganciclovir did not prevent lymphoma development. Our results suggest that in the SCID/hu mouse, early EBV replication and secondary infection of bystander B cells does not occur, and that the direct outgrowth of the transformed B lymphocytes present within the PBMC inoculum is the predominant mechanism, which leads to lymphoma generation in this experimental model.

Adult↗
PubMed2003

[Computerised monitoring of integrated cervical screening. Indicators of diagnostic performance].

In a previous issue of this journal, we presented the background, rationale, general methods, and indicators of participation of a computerised system for the monitoring of integrated cervical screening, i.e. the integration of spontaneous Pap smear practice into organised screening. We also reported the results of the application of those indicators in the general database of the Pathology Department of Imola Health District in northern Italy. In the current paper, we present the rationale and definitions of indicators of diagnostic performance (total Pap smears and rate of unsatisfactory Pap smears, distribution by cytology class reported, rate of patients without timely follow-up, detection rate, positive predictive value, distribution of cytology classes reported by histology diagnosis, and distribution of cases of CIN and carcinoma registered by detection modality) as well as the results of their application in the same database as above.

Adolescent↗
PubMed2002

[The ThinPrep Pap test in population screening].

The ThinPrep technique has been applied to Pap tests in a population screening program in Imola, Italy. A significative decrease in the number of inadequate tests has been observed, while the distribution of the Bethesda diagnostic categories was not different in comparison to the previous year, when conventional Pap tests were used with the adoption of the ThinPrep technique, the productivity of the screening program increased without any need to modify the screening protocol.

Adult↗
PubMed2002

Differential effects of angiostatin, endostatin and interferon-alpha(1) gene transfer on in vivo growth of human breast cancer cells.

The administration of different angiogenesis inhibitors by gene transfer has been shown to result in inhibition of tumor growth in animal tumor models, but the potency of these genes has been only partially evaluated in comparative studies to date. To identify the most effective anti-angiogenic molecule for delivery by retroviral vectors, we investigated the effects of angiostatin, endostatin and interferon(IFN)-alpha(1) gene transfer in in vivo models of breast cancer induced neovascularization and tumor growth. Moloney leukemia virus-based retroviral vectors for expression of murine angiostatin, endostatin and IFN-alpha(1) were generated, characterized, and used to transduce human breast cancer cell lines (MCF7 and MDA-MB435). Secretion of the recombinant proteins was confirmed by biological and Western blotting assays. Their production did not impair in vitro growth of these breast cancer cells nor their viability, and did not interfere with the expression of angiogenic factors. However, primary endothelial cell proliferation and migration in vitro were inhibited by supernatants of the transduced cells containing angiostatin, endostatin, and IFN-alpha(1). Stable gene transfer of the IFN-alpha(1) cDNA by retroviral vectors in both MCF7 and MDA-MB435 cells resulted in a marked and long-lasting inhibition of tumor growth in nude mice that was associated with reduced vascularization. Endostatin reduced the in vivo growth of MDA-MB435, but not MCF7 cells, despite similar levels of in vivo production, and angiostatin did not impair the in vivo growth of either cell line. These findings indicate heterogeneity in the therapeutic efficacy of angiostatic molecules delivered by viral vectors and suggest that gene therapy with IFN-alpha(1) and endostatin might be useful for treatment of breast cancer.

Angiogenesis Inhibitors↗
PubMed2002

Expression and functional activity of CXCR-4 and CCR-5 chemokine receptors in human thymocytes.

In this paper we addressed the expression of the HIV co-receptors CXCR-4 and CCR-5 in human thymocytes by phenotypic, molecular and functional approaches. Cytofluorimetric analysis disclosed that CXCR-4 was constitutively expressed by freshly isolated thymocytes (~10 000 molecules/cell in about 30% of thymocytes); the receptor was endowed with functional activity, as it mediated polarization, migration and intracellular Ca2+ increase in response to its ligand, SDF-1. On the contrary, CCR-5 expression in freshly isolated thymocytes was significantly lower (<4000 molecules/cell in less than 5% of the cells), and no functional response to CCR-5 agonists could be documented. Northern blot analysis of freshly isolated thymocytes showed high CXCR-4 mRNA levels, whereas the message for CCR-5 was barely detectable. On the other hand, a modest increase in the expression of CCR-5 was associated with in vitro thymocyte stimulation, and CCR-5 density at the cell surface attained CXCR-4 figures in most cases. None the less, no functional response to CCR-5 agonists could be documented in in vitro stimulated thymocytes. In vitro infection of thymocytes by CAT-expressing recombinant HIV bearing the envelope glycoproteins from different isolates showed that T-tropic strains, which use CXCR-4 as a co-receptor, were more efficient in infecting thymocytes than M-tropic strains, which preferentially use CCR-5. Altogether, these data indicate that expression of the major co-receptors involved in infection by M-tropic HIV strains is very poor in human thymocytes, and would suggest that thymocyte infection by M-tropic HIV strains may be a rare event in vivo.

Blotting, Northern↗
PubMed2001

Effects of CD2 locus control region sequences on gene expression by retroviral and lentiviral vectors.

Locus control region (LCR) sequences are involved in the establishment of open chromosomal domains. To evaluate the possibility of exploiting the human CD2 LCR to regulate gene expression by Moloney murine leukemia virus (Mo-MLV)-based retroviral vectors in T cells, it was included in vectors carrying the enhanced green fluorescence protein (EGFP) reporter gene; then transduction in vitro of lymphoid and nonlymphoid cell lines was performed. Deletion of the viral enhancer in the Mo-MLV long terminal repeat was necessary to detect LCR activity in the context of these retroviral vectors. It was found that a full-length (2.1 kb), but not a truncated (1.0 kb), CD2 LCR retained the ability to modulate reporter gene expression by Mo-MLV-derived retroviral vectors, leading to a homogeneous, unimodal pattern of EGFP expression that remained unmodified in culture over time, specifically in T-cell lines; on the other hand, viral titer was strongly reduced compared with vectors not carrying the LCR. Lentiviral vectors containing the CD2 LCR could be generated at higher titers and were used to analyze its effects on gene expression in primary T cells. Subcutaneous implantation of genetically modified cells in immunodeficient mice showed that retroviral vectors carrying the CD2 LCR conferred an advantage in terms of transgene expression in vivo, compared with the parental vector, by preventing the down-modulation of EGFP expression. These findings suggest a potential application of this LCR to increase gene expression by retroviral and lentiviral vectors in T lymphocytes.

3T3 Cells↗
PubMed2001

Cervical screening behavior of women with atypical squamous cells of undetermined significance (ASCUS).

Expectant follow-up based on early repeat Papanicolaou (Pap) smear(s) is the most commonly recommended management of patients with atypical squamous cells of undetermined significance (ASCUS). In a cervical cytology laboratory in northern Italy, a retrospective study of 1,087 ASCUS patients aged 25-64 was conducted. The primary aim was to assess the actual probability of early repeat Pap smear and associated factors. Univariate comparisons were based on the actuarial method. Multivariate associations were evaluated by Cox regression analysis. The cumulative probability of early repeat Pap smear was 0.11 at 6 mo, 0.29 at 12 mo, and 0.41 at 24 mo, with a multivariate association with screening sector (relative hazard, 3.0 for public offices and 2.8 for private offices vs. organized screening) and previous Pap smear history. Laboratory recommendation, patient age, place of birth, place of residence, marital status, and occupation exerted no independent effect. In conclusion, the probability of early repeat Pap smear was poor and independent of demographic and social factors. The frequency of follow-up failures emerged as a major problem with ASCUS management.

Adult↗
PubMed2001

Frequency and determinants of lymphadenectomy in endometrial carcinoma: a population-based study from northern Italy.

BACKGROUND: The diffusion of pelvic and para-aortic lymphadenectomy for the surgical pathological staging of endometrial carcinoma into clinical practice has been evaluated only with questionnaire surveys of gynecological oncologists. No population-based information is available. METHODS: In this study of operable endometrial carcinoma cases registered by the population-based Romagna Cancer Registry (northern Italy) between 1987 and 1994, the association of demographic (age, time period, place of birth, place of residence, place of treatment, and marital status) and pathological factors (histological type, tumor grade, myoinvasion, and extension of disease to cervix, serosa, adnexa, and vagina) with the probability of lymphadenectomy was evaluated by multiple logistic regression analysis. RESULTS: Of the 300 potentially eligible cases, sufficient information was obtained for 276 (92%; median age, 63 years; range, 33-87 years). No case of para-aortic lymphadenectomy was observed. Pelvic lymphadenectomy was performed in 86 (31%) cases. The probability of pelvic lymphadenectomy was related to tumor grade (positive association), place of treatment, and marital status. All other variables, including myoinvasion and extension of disease to the cervix and beyond the uterus, had no effect whatsoever. CONCLUSIONS: The most likely interpretations of results include poor acceptance of current surgical pathological staging criteria and insufficient use of standard diagnostic techniques for preoperative and intraoperative assessment of myoinvasion and extrauterine spread.

Adenocarcinoma, Clear Cell↗
PubMed2001

Neopterin production in SCID mice injected with human peripheral blood mononuclear cells.

Intraperitoneal transfer of peripheral blood mononuclear cells (PBMC) from human EBV+ donors into severe combined immunodeficiency (SCID) mice is a suitable model for studying some aspects of lymphomagenesis and immune activation. Neopterin is a soluble immune marker which was found to be a useful indicator for immune activation processes in humans, e.g. to monitor immunological complications in allograft recipients or to predict prognosis in HIV-infected individuals. In contrast, this pteridine compound is normally synthesized in murine organism in only very low amounts. The measurement of neopterin concentrations in serum and urine should be feasible in SCID mice reconstituted with human PBMC. In this study, we examined the usability of this experimental model for monitoring human T cell activation by neopterin measurements. The production of neopterin by SCID mice after injection of freshly isolated human PBMC, purified B or T cells and cultured Epstein-Barr virus (EBV)+ lymphoblastoid cells (LCL) was determined. It was found that neopterin can be detected early after injecting SCID mice with PBMC, whereas injection of purified human T or B cells did not result in neopterin production. Highest neopterin levels were detected in mice treated with LCL cells when developing lymphoma. We discuss the possible sources of neopterin along this process and its usefulness in this model.

Animals↗
PubMed2001

[ASCUS in screening].

The significance and use of the cytological diagnosis "atypical squamous cells of undetermined significance" (ASCUS) remain a major problem in cervical cancer screening. The prevalence of ASCUS by patient age has seldom been investigated. The present paper reports the prevalence of ASCUS in a large series of screening Pap smears from the Italian region of Emilia-Romagna. The study was based on the data collected by the Department of Health of the Emilia-Romagna Region for the first 3-year round (1997-1999) of a population-based screening programme (target age, 25-64 years). The age-specific frequency of ASCUS has been calculated as a prevalence rate per 1000 screened patients. A total of 597,386 women participated in the programme. Women diagnosed with ASCUS (n = 8205 or 13.7 per 1000) accounted for 49% of the recalls for colposcopy (n = 16,871, or 28.2 per 1000). The prevalence of diagnoses of low-grade squamous intraepithelial lesions (LG-SIL) decreased progressively with age while that of high-grade SIL was slightly higher between 30 and 39 years. The prevalence of ASCUS peaked at age 45-49 years (17.3 per 1000 subjects). The observed peak reflects the prevalence of (1) cytological changes closely associated with perimenopausal age and at least compatible with the ASCUS diagnosis, and (2) cytological abnormalities induced by hormone replacement therapy.

Adult↗
PubMed2000

Modulation of Moloney leukemia virus long terminal repeat transcriptional activity by the murine CD4 silencer in retroviral vectors.

We investigated whether CD4 gene regulatory sequences might be useful for developing transcriptionally targeted Moloney murine leukemia virus (Mo-MLV)-based retroviral vectors for gene expression specifically in CD4(+) cells. We could modulate Mo-MLV long terminal repeat (LTR) activity by inserting a 438-bp-long fragment containing the murine CD4 silencer in the LTR of the vector; both beta-galactosidase and green fluorescent protein reporter gene activities were strongly down-regulated in both murine and human CD8(+) cells, but not in CD4(+) lymphoid cell lines and freshly isolated lymphocytes transduced with this vector, compared with the findings using a control vector carrying wild-type LTRs. Titration experiments on NIH-3T3 cells revealed that inclusion of the CD4 silencer in the LTRs did not reduce the titer of the vectors. These findings indicate that a cellular silencer can be successfully included in retroviral vectors, where it maintains its transcription-regulatory function, thus suggesting a novel approach to transcriptional targeting.

3T3 Cells↗
PubMed2000

Effects of complement inactivation and IgG depletion on skin reactivity to autologous serum in chronic idiopathic urticaria.

BACKGROUND: Intradermal injection of autologous serum elicits a wheal-and-flare response in about 60% of patients with chronic idiopathic urticaria (CIU). This reactivity has been attributed to the presence of IgG autoantibodies directed against IgE or the alpha-chain of the high-affinity IgE receptor (FcepsilonRIalpha) expressed on basophils and mast cells, leading to the hypothesis that at least some forms of CIU could be sustained by an autoimmune process. OBJECTIVES: The aim of this study was to investigate the relationship between the presence of anti-IgE or anti-FcepsilonRI antibodies and the ability to induce wheal-and-flare responses in CIU sera selected for the capacity to give a positive skin test response. METHODS: Fifteen patients with CIU and a positive skin test response to autologous serum were injected intradermally with native serum and with serum heated at 56 degrees C for 30 minutes and then adsorbed on Sepharose-protein G to obtain IgG depletion. Serum levels of anti-IgE and anti-FcepsilonRIalpha antibodies were measured by ELISA by using purified IgE and recombinant RIalpha-soluble double-fusion protein RIalpha-human serum albumin-RIalpha, respectively. The histamine-releasing activity of sera was tested by using ELISA with whole human blood from a healthy donor. RESULTS: All patients had positive cutaneous responses to native serum injection. Anti-FcepsilonRIalpha antibodies were present in 14 of 15 native sera, only two of which were able to induce in vitro basophil degranulation. On the contrary, detectable amounts of anti-IgE antibodies were not found in any serum. IgG depletion by protein G resulted in complete (10/14 samples) or considerable (4/14 samples) removal of anti-FcepsilonRIalpha antibodies. The two sera endowed with functional activity lost their capacity to trigger histamine release from basophils after heating and protein G adsorption. Nonetheless, heat-decomplemented/IgG-depleted sera elicited wheal-and-flare reactions comparable with those observed with untreated sera. CONCLUSIONS: These results strongly suggest that skin reactivity to autologous serum could be due to as yet unidentified non-Ig reactants present in the sera of patients with CIU.

Adult↗
PubMed2000

[A new instrument for the evaluation of the medical profession. Use of the OSCE method].

BACKGROUND: Objective structured clinical examination has advantages over traditional oral examination of medical student. However, it is not routinely used in Chile. AIM: To describe the objective structured clinical examination system and report the results of its first use with Chilean medical students. MATERIAL AND METHODS: Thirteen interns ware evaluated at the end of their surgical rotation, using the objective structured clinical examination. Thirteen stations were structured for this examination: one for history taking, two for physical examination, four for problem solving and knowledge, one for radiological interpretation, one for instrumental recognition, one for skills and one for text comprehension. There were a total of 88 questions. RESULTS: All students exceeded 60% of requirements. Mean approval score was 73%. The higher score was 80% and the lower 61%. Ten students had a score over 70%. The method was well accepted by teachers and students. CONCLUSIONS: This first local experience with the objective structured clinical examination was successful.

Chile↗