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Biomedical subjects

M Mazzetti

Publications and source records attributed to M Mazzetti.

At least 19 recordsLinked to original sources
PubMed2004

Determination of 1-phenylazo-2-naphthol (Sudan I) in chilli powder and in chilli-containing food products by GPC clean-up and HPLC with LC/MS confirmation.

A simple and rapid method is reported for the routine determination 1-phenylazo-2-naphthol (Sudan I) in chilli powder and in chilli-containing food products. The method involved Soxtec extraction from the products followed by high-pressure gel permeation chromatographic clean-up collecting the appropriate fraction. Analysis of this fraction was by HPLC with UV/VIS detection. The limit of detection was 7 microg kg(-1) and the limit of quantification was 13 microg kg(-1). The identity of Sudan I in food products was established by electrospray LC/MS with MS/MS confirmation. From a small survey of 30 retail samples, 11 samples of crushed chilli, Italian pasta, chilli-snack and vegetable sauce contained levels of Sudan I ranging from 24 to 5591 microg kg(-1).

Capsicum↗
PubMed2002

Invasive Aspergillosis in Italian AIDS patients.

BACKGROUND: We studied the prevalence, epidemiological features, symptoms, diagnosis, treatment and outcome of invasive aspergillosis in AIDS patients in Italy. PATIENTS AND METHODS: All patients affected by both aspergillosis and AIDS hospitalized between January 1986 and April 1997 (before highly-active antiretroviral therapy, HAART) in four Italian Department of Infectious Disease. Patients were included in the study only if culture, cytology or histology showed firm evidence of Aspergillus infection. Invasive aspergillosis was defined as the presence of characteristic, closely septate hyphae with repeated acute angle branching in either biopsy materials or percutaneous aspirates from tissues other than the lung. Hyphae were identified using hematoxylin-eosin and methenamine silver stain. RESULTS: During the study, 54 out of 2,614 patients admitted with AIDS showed aspergillosis (2.1%). The disease usually occurred in patients with < 50 CD4 cells/mm(3). Aspergillosis was associated with neutropenia and steroid treatment. Nonspecific symptoms were frequently encountered. Fever and cough were both present in > 70% of the cases of pulmonary aspergillosis. Biopsy specimens were analyzed for definitive diagnosis. Invasive aspergillosis is usually treated with amphotericin B, but in 90% of the cases this did not prevent death. CONCLUSION: In AIDS patients with neutropenia and long-term steroid therapy, it is important to consider invasive aspergillosis in the differential diagnosis of opportunistic infections.

AIDS-Related Opportunistic Infections↗
PubMed2001

Autonomic reactivity during viewing of an unpleasant film.

The effect of an aversive, high-arousing film on heart rate, respiratory sinus arrhythmia, and electrogastrographic activity (EGG) was investigated. Previous studies have indicated a larger heart-rate deceleration for visual stimuli depicting surgery or blood compared to neutral content, and this phenomenon is similar to the bradycardia observed in animals in response to fear. The heart-rate deceleration is clearly parasympathetically driven, and it is considered a general index of attention. An accurate index of cardiac vagal tone can be obtained by means of quantification of the amplitude of respiratory sinus arrhythmia. The relationship between cardiac vagal tone and EGG is complex, but animal research has shown that suppressing vagal activity dampens gastric motility. We have investigated whether a movie depicting surgery is associated with greater heart-rate deceleration, larger increase in respiratory sinus arrhythmia, and greater increase in EGG activity compared to a neutral movie. In addition, if both respiratory sinus arrhythmia and EGG are indices of vagal tone, a positive correlation between these physiological responses was expected. Analysis indicated an effect of the surgery movie on heart rate and respiratory sinus arrhythmia, but not on EGG activity. Moreover, the expected correlation was not found. Implications for future studies are discussed.

Adult↗
PubMed2000

Syllables in the processing of spoken Italian.

Five experiments explored the role of the syllable in the processing of spoken Italian. According to the syllabic hypothesis, the sublexical unit used by speakers of Romance languages to segment speech and access the lexicon is the syllable. However, languages with different degrees of acoustic-phonetic transparency give rise to syllabic effects that vary in robustness. It follows from this account that speakers of phonologically similar languages should behave in a similar way. By exploiting the similarities between Spanish and Italian, the authors tested this prediction in Experiments 1-4. Indeed, Italian listeners were found to produce syllabic effects similar to those observed in Spanish listeners. In Experiment 5, the predictions of the syllabic hypothesis with respect to lexical access were tested. The results corroborated these predictions. The findings are discussed in relation to current models of speech processing.

Adult↗
PubMed2000

Enhanced expression of the CXCR4 co-receptor in HIV-1-infected individuals correlates with the emergence of syncytia-inducing strains.

The aim of this study was to investigate the mechanisms responsible for the emergence in some HIV-1-infected individuals of highly aggressive, syncytia-inducing (SI) HIV-1 strains, which have been shown to use CXCR4 as co-receptor to enter target cells. To this end, the percentages of circulating CXCR4+CD4+ T cells were evaluated by flow cytometry in 39 untreated and 61 highly active antiretroviral therapy (HAART)-treated HIV-1-infected individuals in comparison with 35 HIV-1 seronegative subjects. Plasma viremia was also measured, and HIV primary isolates, from both untreated and HAART-treated HIV-1-infected subjects, were tested for the presence of SI strains. The results of this study showed enhanced proportions of CXCR4+CD4+ T cells in untreated patients in comparison with HAART-treated and healthy subjects. Furthermore, the results of a 12-month longitudinal study in a cohort of 11 patients undergoing HAART showed a significant reduction of CXCR4 expression after successful therapy. Finally, a significant positive correlation among the proportions of circulating CXCR4-expressing CD4+ T cells, plasma viremia, and the probability to isolate SI strains was found. These in vivo data are in keeping with previous in vitro results suggesting a bidirectional link between HIV-1 and CXCR4 expression on CD4+ T cells, and provide some clues to understanding the mechanisms exerting a selective pressure toward the emergence of SI strains.

Adult↗
PubMed1998

Cervicofacial and pulmonary actinomycosis associated with non-Hodgkin's lymphoma.

A case of cervicofacial and pulmonary actinomycosis associated with non-Hodgkin's lymphoma (NHL) is reported. The patient underwent antimicrobial treatment and surgical debridement of a palatine lesion. Complete clinical recovery was achieved. The presence of actinomycosis may obscure and delay the diagnosis of NHL.

Actinomycosis↗
PubMed1998

AZT plus methotrexate in HIV-related non-Hodgkin's lymphomas.

AZT is a thymidine analogue useful in the treatment of AIDS. It has been demonstrated that this compound can possess a significant antineoplastic activity when combined with de novo thymidylate synthesis inhibitors, such as 5-fluorouracil (5FU) and methotrexate (MTX). Here we report a review of our data concerning the efficacy and tolerance of the combination AZT + MTX in HIV-related non Hodgkin's lymphomas (NHL). Twenty-nine patients were treated, at weekly intervals, with three (patient 1 to 10) or six (patient 11 to 29) consecutive courses of MTX 1g/m2 and increasing doses of oral AZT (2, 4 and 6g/m2) with leucovorin rescue. Of 26 evaluable patients, a total (complete + partial) response rate of 77% was obtained. The median complete response duration was 16.8 months. There was one therapy-related death due to septic shock. Grade III-IV neutropenia was observed after 19% of the courses, but was prevented by G-CSF administration in 82/119 courses. Grade III-IV anemia was observed after 9% of the courses. In conclusion, the combination AZT + MTX was effective and well tolerated in our series of HIV-related NHL patients.

Adult↗
PubMed1997

3'-Azido 3'-deoxythymidine + methotrexate as a novel antineoplastic combination in the treatment of human immunodeficiency virus-related non-Hodgkin's lymphomas.

We have previously reported that 3'-azido 3'-deoxythymidine (AZT) can possess a significant antineoplastic activity when combined with drugs that disrupt de novo thymidylate synthesis, such as 5-fluorouracil and methotrexate (MTX). The aim of the present study was to evaluate the efficacy and the tolerance of the combination AZT + MTX in human immunodeficiency virus (HIV)-related non-Hodgkin's lymphoma (NHL). Twenty-nine patients (22 men and 7 women), either newly diagnosed or pretreated, have been enrolled in the trial; the median age was 34 years, 45% had acquired immunodeficiency syndrome before lymphoma and 19 patients had less than 100 CD4 lymphocytes/microL. Histologic diagnoses were mainly Burkitt (27%) and diffuse large B-cell lymphoma (45%); extranodal involvement was present in 20 patients. The treatment plan included three weekly courses of MTX at 1 g/m2 (days 1, 8, and 15) plus oral AZT at 2 g/m2 (days 1, 2, and 3), 4 g/m2 (days 8, 9, and 10), and 6 g/m2 (days 15, 16, and 17), plus leucovorin rescue. From the eleventh patient on, in case of complete or partial remission, the treatment was continued with three additional courses, using AZT at the maximum dose. In 26 evaluable patients, the total (complete + partial) response rate was 77% (95% confidence interval, 58% to 89%), with complete remission (CR) in 46% of the patients (95% confidence interval, 29% to 65%). The median CR duration was 12.8 months. Grade III-IV neutropenia and anemia were observed in 52% and 31% of the courses, respectively. There was one therapy-related death due to bacteremia followed by septic shock; the only other recorded infection was a herpes vaginalis. In conclusion, we suggest that AZT + MTX is an effective and well-tolerated regimen in HIV-related NHL.

Adolescent↗
PubMed1996

Relationship of circulating CD4+ T-lymphocytes and p24 antigenemia to the risk of developing AIDS in HIV-infected subjects with oral hairy leukoplakia.

To investigate the relationship of circulating CD4+ T-lymphocytes and p24 antigenemia to the development of AIDS in HIV-infected subjects with hairy leukoplakia (HL), we have followed over eight years 173 HIV-positive patients, all asymptomatic at the start of the study, and compared those who developed HL (n=55) to those who did not (n=118). Both groups included injection drug users (IDUs), homosexual men, and hemophiliacs. At the time of their first visit, both HL+ and HL- patients had a normal value of CD4+ cells and a low frequency of p24 antigenemia. During the years of follow-up, patients in the HL+ group showed a greater reduction in CD4+ cells, a significant increase in p24 antigenemia, and a higher rate of progression to AIDS. Our study demonstrates that in HIV-positive patients, HL is associated with more compromised immunological parameters and a higher viral replication and that its appearance has a negative prognostic value in relation to AIDS progression.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Ability of HIV to promote a TH1 to TH0 shift and to replicate preferentially in TH2 and TH0 cells.

Both interferon gamma (IFN-gamma) produced by T helper 1 (TH1) lymphocytes and interleukin-4 (IL-4) produced by TH2 lymphocytes were reduced in either bulk circulating mononuclear cells or mitogen-induced CD4+ T cell clones from the peripheral blood of individuals infected with human immunodeficiency virus (HIV). There was a preferential reduction in clones producing IL-4 and IL-5 in the advanced phases of infection. However, enhanced proportions of CD4+ T cell clones producing both TH1-type and TH2-type cytokines (TH0 clones) were generated from either skin-infiltrating T cells that had been activated in vivo or peripheral blood T cells stimulated by antigen in vitro when cells were isolated from HIV-infected individuals. All TH2 and most TH0 clones supported viral replication, although viral replication was not detected in any of the TH1 clones infected in vitro with HIV. These results suggest that HIV (i) does not induce a definite TH1 to TH2 switch, but can favor a shift to the TH0 phenotype in response to recall antigens, and (ii) preferentially replicates in CD4+ T cells producing TH2-type cytokines (TH2 and TH0).

Acquired Immunodeficiency Syndrome↗
PubMed1994

Role of TH1/TH2 cytokines in HIV infection.

Different experimental approaches were used to prove or disprove the "TH1/TH2 switch theory" of HIV-infection. No increase, or even a decrease, in the production of TH2-type cytokines (IL-4, IL-5, and IL-10) by either bulk circulating mononuclear cells or CD4+ T-cell clones generated by PHA stimulation of single T cells from HIV-infected individuals in all stages of disease compared to HIV-negative donors was observed. However, enhanced proportions of CD4+ T-cell clones able to produce both TH1-type and TH2-type cytokines (TH0 clones) were derived from either skin-infiltrating, in vivo-activated, T cells or in vitro antigen-stimulated peripheral blood T cells of HIV-infected individuals. Of note, TH1, TH2 and TH0 clones obtained from HIV-seronegative healthy donors showed different ability to support viral replication after infection with HIV in vitro. All TH2 and most TH0 clones supported HIV replication efficiently, whereas TH1 clones did not. These results suggest preferential HIV replication in T cells producing TH2-type cytokines rather than TH1/TH2 switch in HIV infection.

Animals↗
PubMed1994

Characteristics and possible significance of the answers to Rorschach from patients suffering from psoriasis.

The authors have tried to ascertain the statistical significance of the differences between the answers to H. Rorschach Psychodiagnostic tests given to 80 male and female adult patients, suffering from psoriasis and by 'normal' patients. The absolute frequencies and the averages of the results concerning 55 items obtained through the administration of Rorschach to patients with psoriasis were compared with the results of the test made to the general population. The analysis of the data and of the correlations has confirmed the hypothesis that the pathology of psoriasis, is (seriously) damaging, especially as regards the inhibitions, the cerebral potential, the emotional balance and the social relationships of the patient and furthermore, it can be related, ecologically, to problems concerning the identification-individualization process of the patient. This hypothesis has taken into account the high emotional value, in particular as regards the image of oneself, self-acceptance and self evaluation as well as social acknowledgement, and the communicative value given to the skin.

Adult↗
PubMed1994

Psoriasis, stress and psychiatry: psychodynamic characteristics of stressors.

The aim of this investigation was to learn how a stressful event, often very mild, can determine a relapse of psoriasis. The research was carried out with clinical interviews and with the administration of Rorschach Psychoreactive, MMPI and H-T-P tests to 80 in-patients. Our data revealed a high prevalence of psychic disorders: 71.2% of patients showed symptoms which allowed a precise psychiatric diagnosis based on DSM-III-R criteria. 35% had personality disorders, 17.5% were moody, 12.5% were anxious and 6.25% had a schizophrenic trait. The analysis of the stressful events enabled us to determine the presence of a specific event in 88.7% of cases. For the majority of patients, the stressful event was felt as very mild: 67.6% of patients reported the existence of a low-impact stressful event according to the DSM-III-R classification. The average evaluation of the stressful event for all patients, based on a five-stage rating (ranging from 2 'light' to 6 'catastrophic') was 2.56. In conclusion, the analysis of the psychic conditions of in-patients showed that the importance in inducing an acute episode of psoriasis is the meaning of a stressful event as experienced by the patient, i.e. the questioning of his own identity, rather than the intensity of the aforementioned stressful event. In this case, the disease appears to be an attempt to express a defensive somatic response to a possible identity crisis.

Adult↗
PubMed1994

Bile acid malabsorption in AIDS-associated chronic diarrhea: a prospective 1-year study.

OBJECTIVES: In patients with chronic diarrhea associated with acquired immunodeficiency syndrome, bile acid malabsorption, very rarely investigated, may have an important pathogenetic role. METHODS: In this 1-yr prospective study, 15 patients with AIDS-associated chronic diarrhea and 10 AIDS-controls were studied for bile acid malabsorption by means of the SeHCAT abdominal retention test. The patients with diarrhea underwent the glucose hydrogen breath test to identify any bacterial proliferation in the small bowel. RESULTS: In the chronic diarrhea group, only one case of small bowel bacterial overgrowth, and seven cases (47%) with generally severe bile acid malabsorption, were observed. Among the controls, only one had an abnormal low SeHCAT retention. In both cases with Cryptosporidium infection, the SeHCAT test was pathological. CONCLUSIONS: These data are of clinical importance for the pathogenetic study of AIDS-associated chronic diarrhea and for specific treatment with cholestyramine.

AIDS-Related Opportunistic Infections↗
PubMed1992

Infection of peripheral mononuclear blood cells by hepatitis C virus.

We investigated the infection of peripheral blood mononuclear cells (PBMNC) by hepatitis C virus (HCV) in 5 patients with HCV-related chronic hepatitis. The presence of HCV-RNA-positive and -negative strands was tested with the polymerase chain reaction (PCR) method. In all subjects, HCV-RNA was shown in PBMNC. In 3 cases, HCV-RNA was shown in the T- and B-cell populations, with viral RNA also present in the monocyte-macrophage fraction of two of these. HCV-RNA-negative stranded molecules, indicative of the viral multiplication, were significantly increased in cells maintained in cultures with PHA/PMA stimulation. The results indicate that HCV infect blood mononuclear cells, thus suggesting that this cellular tropism may play a role in HCV infection.

Adult↗
PubMed1992

Oral disodium cromoglycate treatment on irritable bowel syndrome: an open study on 101 subjects with diarrheic type.

Several studies on the usefulness of oral disodium cromoglycate (DSCG) in the treatment of systemic adverse reaction to foods have been performed, with less attention to gastroenterological symptoms. In the present study, we selected 101 patients with diarrheic-type irritable bowel syndrome which improved after an elimination diet and worsened after a challenge with specific food(s). All patients were then tested for 48 commercial alimentary antigens by skin prick test (SPT) and underwent 8 wk of oral DSCG (500 mg three times a day), and the results were evaluated by means of a semiquantitative subjective and objective score. We observed an improvement of the symptoms in 67% of the 74 SPT-positive patients, whereas only 41% of the 27 SPT-negative patients showed a positive response to DSCG (p less than 0.05). These data confirm the protective role of DSCG in food-dependent diarrheic-type irritable bowel syndrome with food allergy features.

Administration, Oral↗
PubMed1991

In vitro infection with HIV enables human CD4+ T cell clones to induce noncognate contact-dependent polyclonal B cell activation.

Eleven (nine CD4+ and two CD8+) protein purified derivative-specific and eight tetanus toxoid-specific T cell clones (TCC), established from the peripheral blood of healthy persons, were cocultured in vitro with irradiated mononuclear cells from patients infected by HIV in the presence of PHA and polybrene. Two weeks post-HIV exposure, all 17 CD4+, but neither of the two CD8+, TCC exhibited integration of HIV in their genoma, as detected by polymerase chain reaction analysis, and released HIV into their supernatants, as detected by measuring both reverse transcriptase activity and p24 Ag. When co-cultured with either autologous or allogeneic B cells, all CD4+ HIV-infected TCC induced the synthesis of extraordinarily high amounts of IgM, IgG, and IgA. In contrast, their noninfected counterparts could provide helper function for Ig synthesis by autologous B cells only in the presence of the specific Ag (or anti-CD3 antibody), and induced allogeneic B cells to synthesize Ig only upon stimulation with anti-CD3 antibody. The supernatants of HIV-infected TCC failed to stimulate Ig synthesis in B cells. More importantly, when HIV-infected clonal T blasts and B cells were cultured in different chambers separated by a millipore membrane, permeable to molecules but not to cells, Ig synthesis did not occur. The Ig synthesis induced by HIV-infected TCC was also markedly inhibited by the addition in culture of either anti-CD4 or anti-LFA-1 antibody. In contrast, HIV-infected TCC maintained their ability to provide helper function for Ig synthesis in the absence of any stimulus, even after fixation with p-formaldehyde. These data demonstrate that in vitro infection with HIV enables human T cells to stimulate Ig synthesis by B cells by an Ag-nonspecific, MHC-unrestricted, contact-dependent mechanism. This may explain, at least in part, the hypergammaglobulinemia and other phenomena related to polyclonal B cell activation frequently seen in HIV-infected persons.

B-Lymphocytes↗