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Biomedical subjects

P Mazza

Publications and source records attributed to P Mazza.

At least 19 recordsLinked to original sources

Synthesis, structure, antimicrobial, and genotoxic activities of organotin compounds with 2,6-diacetylpyridine nicotinoyl- and isonicotinoylhydrazones.

A series of organotin compounds obtained from the reaction of 2,6-diacetylpyridine nicotinoyl- and isonicotinoylhydrazones with tri- and diorganotin chlorides was investigated. The IR and 119Sn NMR spectroscopic characterization of all the compounds is reported, together with the x-ray crystal structure of [SnEt2(H2dapin')]2[SnEt2Cl3]Cl3.2H2O (H2dapin' = 2,6-diacetylpyridine bis(isonicotinoylhydrazone)). The main feature in this compound is the presence of a tin atom in both the complex ionic units. The coordination polyhedron is a pentagonal bipyramid in the cation and a trigonal bipyramid in the anion. Results are discussed concerning the in vitro evaluation of antimicrobial properties and genotoxic potential of the compounds described. In all cases the complexes show a reduced antimicrobial activity as compared to that of the corresponding organotin compound. Genotoxic properties of the ligands, detected in the Ames test, disappear in the complexes.

Bacteria

Evidence for a human immunodeficiency virus type 1-mediated suppression of uninfected hematopoietic (CD34+) cells in AIDS patients.

Hematopoietic progenitor (CD34+) cells were purified from the bone marrow of 6 human immunodeficiency virus (HIV) type 1-seropositive cytopenic patients and 10 healthy donors. HIV-1-seropositive patients showed a reduced number of granulocyte/macrophage, erythroid, and megakaryocyte progenitors and also a progressive and significant decline of numbers of CD34+ cells in liquid culture, which did not result from a productive or latent HIV-1 infection of CD34+ cells. However, all HIV-1-seropositive patients showed signs of active viral replication at the bone marrow level. Moreover, virus isolates from 3 HIV-1-seropositive patients showed a dose-dependent inhibition on growth of normal CD34+ cells. This suppressive activity was almost completely reversed by incubating the virus isolates with an anti-gp120 polyclonal antibody before adding to normal CD34+ cells.

Acquired Immunodeficiency Syndrome

Recombinant interleukin-2 (rIL-2) in acquired immune deficiency syndrome (AIDS): preliminary report in patients with lymphoma associated with HIV infection.

In an ongoing phase II study, 12 patients with lymphoma and HIV infection were treated with zidovudine (ZDV) and recombinant interleukin-2 (rIL-2) to evaluate if this association may produce beneficial effect on the immunologic status and the outcome of lymphoma. The protocol included daily doses of rIL-2 at 6 MIU/m2 over 5 days in c.i. per week for a total 4 courses; ZDV was associated at 600 mg/d in the period under study. An improved CD4 count, exceeding 2- to 4-fold the basal count, was obtained in patients with a basal CD4 number greater than 100/microliters accompanied by a significant increase of NK and LAK activity (p less than 0.001). From the clinical point of view the reduction of tumor manifestation was proportional to CD4 basal number; 2 patients from those with CD4 greater than 100/microliters obtained a complete remission after rIL-2 and ZVD. The p24 antigen, taken as parameter of viral replication, remained invariably negative after rIL-2 and ZDV in patients already negative and became negative in 1 patient previously positive. Our conclusion is that the association of rIL-2 and AZT is safe and useful in patients with lymphoma and HIV infection.

CD4-Positive T-Lymphocytes

Work capacity and cardiopulmonary adaptation of the obese subject during exercise testing.

Twelve obese patients (six male subjects) aged 17 to 42 years with a mean body mass index (BMI) of 40 kg/m2 and 12 normal subjects (six male subjects) aged 19 to 39 years with a mean BMI of 22 kg/m2 underwent a cycloergometric test until exhaustion to assess work capacity and cardiopulmonary adaptations of the two groups. Minute ventilation, expiratory gas concentrations, and heart rate, together with anaerobic threshold (AT) were determined in each subject during the test. The same subjects were then submitted to normocapnic hyperpnea at rest to assess the oxygen cost of breathing. We found that in the obese patients, the maximal sustainable work rate was not different from that of controls (120 vs 136 W) while AT was significantly lower (78 vs 110 W). Nevertheless, there was no difference in maximum VO2 and in VO2 at AT levels (expressed in milliliters per minute) indicating that cardiac, pulmonary, vascular, and muscle performance did not differ from obese to normal subjects. Greater muscular effort was needed by obese patients when moving their heavier legs and less when doing external work with a decreased gross mechanical efficiency and an identical net mechanical efficiency between the two groups.

Adaptation, Physiological

Massive mediastinal involvement in stage I-II Hodgkin's disease: response to combined modality treatment.

Thirty-seven patients with stage I-II Hodgkin's disease and massive mediastinal involvement, observed between June 1981 and November 1989, underwent combined modality treatment. This treatment included: 3 cycles of mechlorethamine, vincristine, procarbazine, and prednisone followed by mantle-field irradiation, and subsequently by 3 additional cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine. Thirty-five (95%) patients achieved complete responses and only 2 (5%) had partial responses. All the complete responders are living and relapse-free at a median follow-up of 62 months; no major toxic reactions were recorded. These data suggest, as did those of other studies, that combined modality therapy is superior to either radiotherapy or chemotherapy alone for patients in stage I-II with bulky disease, especially in the mediastinum. In fact, in these particular patients, if adequately treated with a combination of chemotherapy and radiotherapy, the role of massive mediastinal involvement as a poor prognostic factor appears to be less significant.

Adolescent

Studies on the antibiotic resistance of Bacillus subtilis strains used in oral bacteriotherapy.

Bacillus subtilis antibiotic resistant strains used in oral bacteriotherapy were tested for the resistance to new therapeutically useful antibiotics. Chromosomal mutations originally selected in these strains proved to confer resistances also to these antibiotics. To investigate the stability of the antibiotic resistance markers present in B. subtilis O/C, T, N/R, SIN strains, we considered resistances to Chloramphenicol, Tetracycline, Rifampicin and Streptomycin. Resistances to Tetracycline, Rifampicin and Streptomycin were stably maintained for at least 200 generations in the absence of selective pressure. Chloramphenicol resistance proved to be inducible, showing a progressive loss when the resistant strain was grown in the absence of the antibiotic and a return to its original resistance levels after growth in the presence of the antibiotic. By in vitro and in vivo experiments we demonstrated the absence of homologous transfer of resistance markers among the resistant strains.

Anti-Bacterial Agents

Catecholamine-stimulated potassium transport in erythrocytes from normal and obese subjects.

The beta adrenergic-modulated Na+/K+ ATPase pump rate of red blood cells was measured in vitro in 18 non diabetic obese patients. After challenge of erythrocytes with beta adrenergic selective agonist Salbutamol, the decrement of the K+ concentration in the suspending medium was assumed to be related to the Na+/K+ ATPase pump rate or to the number of beta 2 receptors. The mean K+ uptake was markedly increased in the erythrocytes of obese patients (1.58 mEq/l SD 0.18) if compared with 38 normal subjects (1.30 mEq/l SD 0.11) and with a population of 30 atopic patients that we have previously reported to have a reduced red cells beta 2 receptor activity (1.09 mEq/L SD 0.11). These results are not consistent with the hypothesis that a reduction in the Na+/K+ ATPase pump rate (at least in red blood cells) may be responsible for decreased metabolic rates leading to obesity. Since the autonomic nervous system is involved in the regulation of the cardiovascular system, it is conceivable that an increased Na+ ATPase pump rate (or supersensitivity) may be responsible of the increased incidence of hypertension, congestive heart failure and unexplained sudden death associated with obesity in some patients.

Adult

Cutaneous response to intradermal histamine in lung cancer.

Recent evidence has suggested that human neoplastic patients show decreased blood histamine levels and cutaneous responses to intradermal histamine. In this study we evaluate the skin response to intradermal injections of histamine and IgE levels in 34 male patients with lung cancer (of which 21 had metastasis) and in 16 control subjects. Analysis of our data does not reveal any difference in the areas of wheal and flare between control subjects and lung cancer patients with or without metastasis. Moreover the evaluation of the different histologic cell type of lung cancer provides the same results. In addition, the sensitivity (Histamine Threshold Concentration) and reactivity (slopes) to histamine is not statistically different. No difference is found for IgE levels between controls and cancer patients. In the light of our finding we believe that in lung cancer patients skin response to intradermal histamine is not decreased, and therefore that the hypothesis concerning the existence of H1-histamine receptor antagonist released by tumour is not confirmed.

Aged

Studies on the genotoxic properties of essential oils with Bacillus subtilis rec-assay and Salmonella/microsome reversion assay.

Genotoxic properties of essential oils from Anthemis nobilis L., Artemisia dracunculus L., Salvia officinalis L., Salvia sclarea L., Satureja hortensis L., Satureja montana L., Thymus capitatus L., Thymus citriodorus Schreb., Thymus vulgaris L., Citrus bergamia Risso, were studied with Bacillus subtilis rec-assay and Salmonella/microsome reversion assay. The essential oil of Artemisia dracunculus L. "Piemontese" turned out to be active in the rec-assay but not in the Salmonella test. DNA-damaging activity was demonstrated to be due to the estragol component of the oil. Advantages of the combined use of these two short-term microbial assays in genotoxic studies are discussed.

Animals

Is interferon alpha in cutaneous T-cell lymphoma a treatment of choice?

This study was designed to evaluate the therapeutic efficacy and toxicity of recombinant interferon alpha-2a (rIFN alfa-2a) given as initial systemic therapy in untreated mycosis fungoides and/or Sezary's syndrome patients, at a slowly escalating schedule up to the maximal tolerated dose. At the same time this schedule was administered in patients who had relapsed or were refractory to previous treatment; 28 newly diagnosed and 15 previously treated patients entered the study. IFN was given daily with dose escalation from 3 to 18 MU. The last follow-up in June 1990 indicates that 90% of previously untreated patients who obtained a complete remission remain in continuous complete remission after 18 to 40 months and that 75% of previously untreated patients who obtained partial remission remain in partial remission after 20-44 months. The event-free survival projected, calculated using the Kaplan and Meier product limit technique, was 21% of all patients at 54.7 months (40% in the previously untreated groups and 14% in the previously treated group: P = 0.12). In conclusion, interferon is very effective as a single agent in cutaneous T-cell lymphomas.

Adult

Relationship between body mass and tolerance to physical stress in obese patients.

Eleven obese patients, 5 males; age: 17-42; body mass index (BMI): 40; % of ideal weight: 187%, and 10 normal subjects (5 males; age: 19-39; BMI: 22; % of ideal weight: 103%), both groups without heart and respiratory disorders, underwent a cycloergometric test with subsequent 20-watt increases every 4 min until exhaustion. During the test, ventilation/minute, expiratory gas concentration and heart rate were measured, and the anaerobic threshold (AT) was determined in each subject. The obese patients showed a significantly lower AT than normal subjects (p less than 0.01); showing values which decreased with the increase in the grade of obesity expressed in BMI or in percent of their ideal weight. Moreover, in the obese patients, the O2 consumption (VO2) had significantly increased compared to that of normal subjects at no resistance and at all work levels. The negative correlation between the AT value and the BMI in obese patients can attribute their increase in VO2 during stress to (1) the inertial overloading caused by obesity especially considering the adipose tissue of their legs, or (2) to their level of 'fitness' being lower than that of normal subjects.

Adolescent

Second primary cancer following Hodgkin's disease: updated results of an Italian multicentric study.

The risk of second primary cancer (SPC) was evaluated in 947 patients treated for Hodgkin's disease (HD) during the period January 1969 to December 1979. The median follow-up of this series was 10.5 years (range, 9 to 19). Treatment categories included radiotherapy (RT) alone (115 patients, 12%), chemotherapy (CHT) alone (161 patients, 17%), combined RT plus CHT (381 patients, 40%), and salvage treatment for resistant or relapsing HD (290 patients, 30.6%). Fifty-six SPCs were observed, occurring between 1 and 17 years from initial treatment. Among these, secondary acute nonlymphoid leukemia (s-ANLL) was the most frequent SPC (23 cases). Secondary non-Hodgkin's lymphoma (s-NHL) occurred in 5 patients, whereas a secondary solid tumor (s-ST) was observed in 28 patients. The calculated actuarial risk (+/- SE) of developing SPC was 5.0% (+/- 0.9%) and 23.1% (+/- 5.8%) at 10 and 19 years, respectively. Concerning treatment modalities and s-ANLL risk, no cases were observed in the radiotherapy group, whereas CHT plus RT and salvage groups showed the highest actuarial risk. This was, in fact, at 10 and 19 years, 3.1% (+/- 0.9%) and 8.1% (+/- 4.0%) in the former group, and 1.8% (+/- 1.0%) and 16% (+/- 9.0%) in the latter. A statistically significant difference was observed when the CHT plus RT group was compared with CHT and RT groups (P = .04). Concerning the relationships with chemotherapeutic regimens, 12 s-ANLL cases occurred in the mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) plus RT group, and only one case in the group receiving doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) plus RT. A statistically significant difference of s-ANLL actuarial risk was found comparing patients receiving MOPP plus RT to all other treatment groups (P = .04). With respect to s-ST, the actuarial risk at 10 and 19 years was 2.0% (+/- 0.6%) and 13.0% (+/- 3.8%), respectively. No significant differences were found among groups treated with different modalities. These data were confirmed by a multivariate analysis, which indicated treatment modality and age as independent variables for s-ANLL and s-ST development, respectively. Based on the prolonged follow-up analysis, the actuarial SPC risk at 10 years hereby reported should reflect the real SPC incidence in our series.

Actuarial Analysis

MACOP-B vs F-MACHOP in the treatment of high-grade non-Hodgkin's lymphomas.

From September 1988 two hundred-sixty-seven (267) untreated patients (pts) with stage II to IV high grade non Hodgkin's lymphoma (NHL) have been enrolled in a multicenter, randomized, still ongoing study, comparing two third-generation combination chemotherapy regimens, MACOP-B versus F-MACHOP. At the present time, 177 pts have completed the treatment program and are evaluable, with a median follow-up of 13 months. Clinical, histologic and laboratory characteristics are equally distributed in both groups. Among the 92 pts treated with MACOP-B, 58 (63%) achieved a complete remission (CR), 17 complete responders have relapsed (29%), and 21 have died (23%), including 3 treatment-related deaths. Among the 85 pts who received F-MACHOP, 65 (76%) achieved a CR, 9 complete responders have relapsed (14%), and 11 pts have died (13%), including 3 treatment related deaths. 30 months-projected survival is 64% for MACOP-B treated pts compared to 84% for F-MACHOP treated pts; 30 months-projected relapse- free survival is 80% and 84%, respectively. F-MACHOP seems to be superior in immunoblastic lymphoma (overall survival, OS, 82% vs. 54%) and in Burkitt-type lymphoblastic lymphoma (OS 100% vs, 42%). The degree of hematological and non-hematological toxicity was similar in both regimens. More reliable conclusions will be drawn after a longer follow-up.

Adult

Nine years' experience with ABMT in 128 patients with Hodgkin's disease: an Italian study group report.

One-hundred, twenty-eight patients with Hodgkin's disease in remission or who had failed a mechlorethamine, vincristine, procarbazine and prednisone (MOPP), a doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) and/or lomustine, etoposide and prednimustine (CEP) regimens have been treated with a high-dose therapy (HDT) containing cyclophosphamide, etoposide, carmustine (CVB) and autologous bone marrow transplantation (ABMT). Forty patients were treated while they were in resistant or progressive disease states using alternating MOPP/ABVD protocol; 15 patients received ABMT in first relapse; 51 patients had a complete remission (CR) with first-line therapy but later relapsed and then received conventional salvage therapy; 16 achieved no response or progression ("resistant relapse" patients) and 35 responded partially or completely ("sensitive-relapse" patients). The other 22 patients received ABMT in remission. Following HDT, 56 patients (52.8%) achieved CR and 23 patients (21.6%) achieved a partial remission for an overall response rate of 74.4%. Sixteen patients failed to respond and died in progressive disease 1 to 10 months (median 6 months) after ABMT. High-dose therapy produced severe toxicity including vomiting (100%), mucositis (75%) and liver enzymes and alkaline phosphatase elevations (51%). There were 10 treatment-related deaths. A multivariate analysis identified poor performance status and resistant-relapse patients as very important adverse risk factors for survival immediately after ABMT. These results, while validating this procedure for inducing remissions in advanced highly-treated patients, at the same time confirm the need of employing this approach in first relapse or in second complete remission after standard therapy and before ABMT or, in first complete remission in very high risk Hodgkin's disease patients. Our experience in 15 very poor prognosis Hodgkin's disease patients transplanted in first CR demonstrated to be much significant.

Adult