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Biomedical subjects

P Ballerini

Publications and source records attributed to P Ballerini.

At least 55 records · Page 3Linked to original sources
PubMed1989

Two antiemetic regimens do not impair chemical xenogenization induced in vivo by 5-(3,3-dimethyl-1-triazeno)-imidazole-4-carboxamide.

The possible interference with 5-(3,3-dimethyl-1-triazeno)-imidazole-4-carboxamide (DTIC)-mediated chemical xenogenization (CX) by antiemetic drugs was studied. DTIC was given alone or in combination with either dexamethasone or metoclopramide plus orphenadrine hydrochloride plus diazepam to CD2F1 mice bearing the histocompatible L1210 leukemia. Tumor cells were collected from treated animals and inoculated into histocompatible untreated and drug-treated recipients, for eight transplant generations. More than 50% of intact hosts rejected tumor cells between the fourth and sixth transplant generation, independently of antiemetic treatments. Positive controls treated with DTIC plus quinacrine (QC) confirmed that this antimutagenic compound entirely abrogates CX. The present results point out that the antiemetic regimens investigated in this study do not prevent CX. Since DTIC treatment requires intensive antiemetic support in man, these data are of clinical relevance for CX-oriented immunochemotherapy protocols.

Animals↗
PubMed1989

Changes of immunological patterns of human cancer cells treated in vitro with a triazene compound.

Previous experimental evidence indicates that immunogenicity of mouse tumor cells can be increased by treatment with dacarbazine and other triazene compounds. The present studies have been conducted on the human cell lines H125 (lung cancer), 1246 (melanoma), X3 (EBV-immortalized B cells) subjected to in vitro treatment with 4 (3-methyl-1-triazeno) benzoic acid potassium salt (MTBA). Untreated or drug-treated sublines were tested for susceptibility to allogeneic NK effector cells, either non-stimulated or pretreated with beta-Interferon. In the case of X3 cell line and its MTBA-treated subline the expression of the EBV-associated antigens and the capability of eliciting autologous cytotoxic T lymphocytes (CTL) were also investigated. The results suggest that a modification of membrane antigenic pattern could be induced by MTBA treatment in terms of changes of cell susceptibility to cell-mediated lysis, expression of EBV-related antigens and capability to elicit autologous CTL.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1988

Hormonal changes induced by the pure antiandrogen flutamide in postmenopausal women with advanced breast cancer.

Hormonal changes induced by the pure antiandrogen flutamide were studied in three postmenopausal metastatic breast cancer patients. The drug was administered at a dose of 250 mg, three times a day for 3-6 months. In each patient a sharp decrease of about 50% was observed in the circulating levels of DHT and DHEAS, irrespective of pretreatment values. A concomitant, although less pronounced, reduction in circulating testosterone, androstenedione and estradiol was found. A decrease in circulating steroids was associated with a 30% decrease in SHBG concentrations in two patients; in the third patient a 30% increase occurred. Androgens in urine, namely testosterone, androstanediol and 17-KS, decreased accordingly. In addition, a marked decrease in 17-OHCS occurred in two of the patients. These data indicate that flutamide is an effective antiandrogen in women and suggest two possible mechanisms by which the drug exerts its antiandrogenic activity: (a) inhibition of conversion of testosterone into the more active DHT, and (b) inhibition of synthesis of the adrenal precursors of active androgens. Minor variations in circulating LH and FSH were observed. Pretreatment prolactin values, which were higher than normal, dramatically decreased by 90% in one patient who had a partial remission of her disease, and they further increased in another patient who relapsed while on therapy.

Anilides↗
PubMed1988

Sodium and calcium dependence of purine release from rat cerebral cortical slices.

Electrically evoked purine release from rat cerebral cortical slices was evaluated, using a HPLC analysis combined with radioactivity measurement of the identified fractions. Two different pools of released purines have been identified: one probably related to cell metabolism and the other strictly linked to the nervous transmission. Since a linear increase, due to the stimulation frequencies, was found for the purines released from this second pool, a possible dependence on sodium and calcium transmembrane fluxes was evaluated. Pretreatment of the slices with TTX (5 x 10(-7) M) caused only a partial inhibitory effect on purine release (50%). This effect was probably related to the drug activity on the neuronal component of slices, since TTX induces an almost complete inhibition of purine release from isolated neurons "in cultures" and does not affect it from glial cells. Verapamil (1 x 10(-4) M), a calcium-channel blocker at glial and neuronal level, and TEA (3 x 10(-2) M), a specific inhibitor of calcium-mediated potassium efflux from glial cells, administered to the slices alone or in combination, showed a partial calcium-dependence of purine release. These results suggest a glial role in modulation of electrically-evoked purine release. These cells could exert a "buffering action" that regulates the calcium-mediated potassium availability, by which neuronal activity might be influenced.

Adenosine↗
PubMed1988

Cultures of glial cells release purines under field electrical stimulation: the possible ionic mechanisms.

Dissociated primary cultures of glial cells released a remarkable amount of purines, at rest and during field electrical stimulation. The HPLC identification of labelled compounds derived from 3H-Adenosine (3H-Ado) (employed to preload the cultures) indicated that nucleotides and nucleosides were represented in the superfusate in equivalent proportions (43.86% and 56.14% respectively). Very much higher amounts of unlabelled purines prevalently constituted by nucleotides compounds (91.10%) were also released and detectable in the superfusate. In all the experimental conditions their evoked release did not result frequency-dependent. Since: a linear increase related to the stimulation frequencies was found for the released labelled compounds; no labelled purines were assayed in 5 x 10-5M Dipyridamole-treated cultures; any significant presence of labelled nucleotides, inosine and hypoxantine was not found in cultures simultaneously treated with 1 x 10-5M 2'-deoxycoformycin and 1 x 10-4M 1-(-5-isoquinolinsulfonyl)-2-methylpiperizine (H7) (3H-Ado amounts resulted more than doubled in these experimental conditions); labelled compounds have been assumed as tracers of a glial purine rate whose release can be connected to electrically-evoked action potentials. Purine outflow from glial cells is not sodium dependent, in fact TTX (5 x 10-7M) did not affect their basal or electrically-evoked release. A remarkable calcium-dependence was also evidentiated by the 1 x 10-4M Verapamil-induced inhibition of basal and evoked release. TEA (1 x 10-2M), a specific inhibitor of potassium efflux throughout calcium-mediated specific channels, strongly reduced the evoked purine outflow and any additive effect of its was not detectable when administered simultaneously to the calcium antagonist. These findings indicate that the frequency-dependent purine release from cultured glial cells is linked to ionic mechanisms, which calcium and potassium are mainly involved in.

Adenosine↗
PubMed1987

[Screening and vaccination against hepatitis B among health personnel. Short-term results].

In the framework of the campaign for anti-HBV vaccination conducted by the Regione Piemonte, the Mauriziano Hospital in Valenza and the Unità Sanitaria Locale 71, screened and then vaccinated a group of 199 medical workers at risk of HBV. It was found that the infection was asymptomatic in the vaccinated subjects (16%) and the chronic HBsAg carriers (1.5%), that the risk of infection increases with age (p less than 0.01) and length of service (p less than 0.05) and that there is a connection with the mean figures produced by other studies conducted on hospital staff. Vaccination gave satisfactory results, with protective antibody responses in 87% of the cases, of whom about half presented levels over 1000 mIU/ml and no significant side effects.

Adult↗
PubMed1987

Immunopharmacological studies of PTT.119, a new synthetic bis-(2-chloroethyl)amino-L-phenylalanine derivative.

The new synthetic tripeptide p-F-Phe-m-bis-(2-chloro-ethyl)amino-Phe-Met-etoxy HCl, PTT.119, was studied for its effects on the host immune system. Doses of PTT.119 ranging from 3 to 18 mg/kg were administered i.p. to recipient mice which, at different times after drug treatment, were tested for allograft response, competence in producing lymphocytes active in lethal graft-versus-host disease, delayed-type hypersensitivity, mitogen responsiveness, humoral antibody production and natural resistance against microbial infections. At therapeutically active dosages, PTT.119 appeared to selectively inhibit functions mediated by B lymphocytes, leaving the majority of those involving T-cell subsets largely unaffected, even at the highest doses employed. Moreover, drug treatment had also a limited impact on the in vivo resistance of mice to microbial infection, which was only affected by a drug injection of 18 mg/kg, a dose well within the confidence limits of the mean lethal dose of the drug.

Animals↗
PubMed1986

[Management of a clinical pathology laboratory using a record system on personal computer data base].

Data collection and processing via a Report System Data Base (dBASE III) is a new method recently implemented on Personal or Microcomputer. The major advantage compared to other systems lies in the possibility of working simultaneously with several open files that interact amongst themselves practically in real time. Procedures and programmes can also be created without the need to convert them to machine language. Management of the Clinical Pathology Laboratory via dBASE III is described. The Data Base Record files were specially created. Data on the necessary alteration in mass storage dimensions are supplied on the basis of the number of tests to be carried out. Preliminary information on the possibility of translating currently used statistical equations through the keyboard are also given. The package produced is absolutely interactive and does not require special training. It may therefore be used easily both by the laboratory doctor and personnel responsible for input and reference.

Clinical Laboratory Techniques↗
PubMed1986

[Seroepidemiologic case finding in HTLV III infection, lues and HBV in a prison].

We report serological screening of 1217 prisoners for HTLV III antibodies, HBV markers and lues tests. The prevalence for HTLV III Abs on the whole of prisoners controlled is 30.8%, among the drug-users is 60.7%, with a relative risk (RR) of 1.18 between males and females in this group. It is been observed a significant association between aspecific positivity to VDRL and HTLV III Abs in the serum.

Acquired Immunodeficiency Syndrome↗
PubMed1983

[Rotavirus infections in a neonatal pathology unit].

From February to June 1981, 38 newborn babies admitted to a special care unit were examined to determine the incidence of rotavirus infections. Fecal specimens were collected from all babies on the fifth day after birth and thereafter weekly. The stool samples were examined with an immunoenzymatic test. Serum was collected from the newborn babies and from their mothers three days after delivery. Thereafter more serum was collected from the babies at intervals. Serum was also collected from the hospital staff. Rotavirus was detected in one or more of the stool samples taken from 20 (53%) of the 38 newborn babies. Of these 20, 11 (55%) were already positive in the first specimen. Three babies still had rotavirus in their faeces after four weeks. No relation was noted between the admission to one or the other of the two wards in the unit and the presence of rotavirus in their stools. Complement fixing antibody (CFA) titers in the babies were not different from those in the mothers. A decline of antibody levels was observed in all the babies whether they were rotavirus positive or negative. Only three of the babies without CFA in the first serum sample had a significant increase of the titer while rotavirus was not found in their stools. The CFA titer geometric mean was significantly higher for babies who were found to have rotavirus from the first stool sample than for those whose subsequent samples were found to be positive. Moreover, the CFA titer geometric mean for the hospital staff was significantly higher than that of the mothers. Mild gastrointestinal symptoms were observed in 70% of the newborn babies having rotavirus in their stool and in 39% of those without rotavirus. However, this difference did not prove to be significant.

Cross Infection↗