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C Bianchi

Publications and source records attributed to C Bianchi.

At least 19 recordsLinked to original sources
PubMed1992

Para-substituted Phe3 deltorphin analogues: enhanced selectivity of halogenated derivatives for delta opioid receptor sites.

The delta-selective opioid peptide deltorphin C(H-Tyr-D-Ala-Phe-Asp-Val-Val-Gly-NH2) (DEL C) was modified by para-substitution of Phe3 with halogens (F, Cl, Br, I), amino, or nitro groups. The bioactive potencies in peripheral tissues and brain receptor selectivities of these analogues depended upon the particular substituent; peptides containing halogen substituents exhibited the least disruptive effect. In the mouse vas deferens (MVD) bioassay, [p-ClPhe3]DEL C displayed equivalent bioactivities to DEL C; in combination with the guinea pig ileum (GPI) bioassay, [p-ClPhe3]DEL C and [p-BrPhe3]DEL C exhibited marked preference for delta sites (IC50GPI/IC50MVD = 11,250 and 6,363, respectively), which are approximately 4- and 2-fold greater than DEL C. In a receptor binding assay, none of the halogenated analogues had delta affinities (Ki) exceeding that of DEL C; however, in terms of delta selectivity (Ki mu/Ki delta), [p-BrPhe3]DEL C was nearly twice as selective as DEL C, while [p-FPhe3]DEL C was equivalent, and [p-IPhe3]DEL C only 25% less selective. The only correlation evident with the halogenated derivatives occurred between IC50GPI and Ki mu (r = 0.814) rather than between delta receptor studies (MVD or Ki delta); interestingly, IC50GPI also correlated with K' (r = 0.982). The p-amino or p-nitro substituents of Phe3 in DEL C and DEL B (= [Glu4]DEL C) were deleterious for bioactivity (MVD) (losses ranged from 400- to approximately 8,000-fold) and in receptor binding assays, where delta affinities decreased 140- to 840-fold and delta selectivities by 34- to 380-fold. p-Nitro-Phe3 was the most detrimental substitution for all the parameters measured for both deltorphins: the loss in MVD activity, however, was less with DEL B than with DEL C, which was the opposite for delta receptor affinity.

Amino Acid Sequence↗
PubMed1992

Polypeptide composition of the 8S form of prolyl-tRNA synthetase from rat liver.

Rat liver Fraction X containing the 24S complex of nine aminoacyl-tRNA synthetases, including prolyl-tRNA synthetase, was centrifuged on a 15-35% sucrose density gradient to obtain the 8S form of prolyl-tRNA synthetase. The enzyme was purified on a prolyldiaminohexyl-Sepharose 4B affinity column, specifically binding prolyl-tRNA synthetase to Sepharose-bound proline. After SDS-polyacrylamide gel electrophoresis, two peptides of 58 and 61 kDa were detected in the peak of prolyl-tRNA synthetase activity eluted from the affinity column. The 58 and 61 kDa peptides were also present in the 24S complex containing prolyl-tRNA synthetase activity isolated on the sucrose density gradient.

Amino Acyl-tRNA Synthetases↗
PubMed1992

Pain in ambulatory patients with lung or colon cancer. Prevalence, characteristics, and effect.

BACKGROUND: Few studies have evaluated the epidemiology and effect of pain in ambulatory patients with cancer who are undergoing active therapy. This information is needed to develop strategies for supportive care in this population. METHODS: The prevalence and characteristics of pain were determined in a prospective survey of ambulatory patients with lung or colon cancer. To reduce bias and acquire comprehensive information, the methodology used face-to-face interviews by trained quality assurance analysts, a multifaceted assessment instrument, and multivariate statistical analysis. RESULTS: In a telephone interview, "persistent or frequent" pain during the previous 2 weeks was reported by 57 of 145 (39.3%) patients with lung cancer and 52 of 181 (28.7%) patients with colon cancer; 91 of these patients (47 lung and 44 colon) were interviewed in detail. All patients had excellent performance status, and with the exception of pain location, there were no significant differences between the two tumor types. One-third of the patients had more than one discrete pain. Median pain duration was 4 weeks (range, less than 1 week-468 weeks), and average pain intensity was moderate. Approximately 90% of patients experienced pain more than 25% of the time. Pain interfered moderately or more with general activity and work in approximately half of the patients; more than half reported moderate or greater pain interference in sleep, mood, and enjoyment of life. Multiple regression analysis revealed that the daily frequency of pain, the intensity of the worst pain, the score on a mood scale, and the frequency of the worst pain accounted for 58.7% of the variance in average pain intensity. Likewise, 52.1% of the variance in a derived measure of pain interference in function was explained by the mood score, frequency of the worst pain, number of pains, and pain intensity. CONCLUSIONS: These data indicate that pain is prevalent among well-functioning ambulatory patients and substantially compromises function in approximately half of the patients who experience it. Pain is a complex symptom; aspects other than intensity, such as frequency, strongly influence its effect.

Aged↗
PubMed1992

Muscarinic modulation of acetylcholine release from slices of guinea pig nucleus basalis magnocellularis.

Spontaneous and electrically evoked endogenous acetylcholine release and [3H]-choline efflux from slices of guinea pig nucleus basalis magnocellularis (nbM) were studied. Tetrodotoxin reduced the spontaneous endogenous release by 55%, while the Ca(2+)-free medium reduced it by about 30%. Evoked [3H]-choline efflux was Na+ and Ca2+ dependent and frequency related. Physostigmine, 30 microM, nearly halved the stimulation-evoked efflux; atropine, 0.15 microM, not only antagonized, but even reversed this effect into facilitation. Pirenzepine, 1 microM, and AFDX 116, 1 microM, were less effective than atropine, and reversed the inhibitory effect of physostigmine only when applied together. 4-DAMP, 0.01 microM, was ineffective. These findings indicate that acetylcholine release in guinea pig nbM slices is inhibited by the cooperation of muscarinic autoreceptors, possibly belonging to the M1 and M2 subclasses.

Acetylcholine↗
PubMed1992

Malignant mesothelioma of the pleura in Trieste, Italy.

One hundred and seventy malignant pleural mesotheliomas seen at necropsy at the Institute of Pathological Anatomy of the Trieste University during the period 1968-1987 were reviewed. The series included 153 men and 17 women, aged between 33 and 92 years (median 70 years). Lifetime work histories were obtained from the patients' relatives by personal or telephone interviews in 162 cases. A majority of the male subjects had been employed in "naval" work, 99 people having worked in the ship-building industry, 19 in the navy and merchant marine, and 7 in docks. A variety of trades appeared in the remaining histories. Work histories were indicative of occupational exposure to asbestos in 150 cases. A further 5 patients with negative or insufficient data showed asbestos bodies in routine lung sections and 5 women had a history of domestic exposure. A majority of the patients had had their first exposure before 1950. The intervals between first exposure and death ranged from 14 to 71 years (median 48 years).

Adult↗
PubMed1992

Inhibitory effects of the psychoactive drug modafinil on gamma-aminobutyric acid outflow from the cerebral cortex of the awake freely moving guinea-pig. Possible involvement of 5-hydroxytryptamine mechanisms.

The effects of modafinil on acetylcholine and GABA outflow from the cerebral cortex of awake freely moving guinea pigs provided with an epidural cup were studied. In the dose range of 3-30 mg/kg s.c. modafinil produced a dose dependent significant inhibition of GABA outflow without influencing cortical acetylcholine release. Methysergide (2 mg/kg, i.p.) and ketanserin (0.5 mg/kg, i.p.) but not prazosin (0.14 mg/kg, i.p.) counteracted the inhibitory action of modafinil on cortical GABA outflow. Modafinil both acutely and chronically in the same dose range increased striatal 5-HIAA levels and 5-HT utilization in the rat (acute) and mouse (chronic). The action on cortical GABA release may be dependent on activity at 5-HT2 receptors, since the action of modafinil in this respect is blocked by the non-selective 5-HT antagonist methysergide and the 5-HT2 antagonist ketanserin. The involvement of 5-HT mechanisms in the inhibitory action of modafinil on cortical GABA release is also suggested by the findings that 5-HT metabolism may become increased by modafinil at least in the striatum. The reduction of cortical GABA outflow via 5-HT2 receptors by modafinil is probably related to some of its actions on the central nervous system including behavioural effects.

Acetylcholine↗
PubMed1992

Importance of reperfusion on thromboxane A2 metabolite excretion after thrombolysis.

Fibrinolytic therapy is a major advance in the treatment of coronary artery disease. A marked elevation in plasma and urinary metabolites of thromboxane A2 (TXA2) after administration of thrombolytic therapy has been observed and has been related to a direct effect of thrombolytic drugs on platelets. To test this hypothesis we evaluated the 11-dehydro-thromboxane B2 (11-d-TXB2) level, as an index of platelet activation, in 20 healthy subjects and in 30 patients with acute myocardial infarction (AMI). Patients with infarction received streptokinase (n = 8), recombinant tissue-type plasminogen activator (rt-PA) (n = 8), or thrombolytic therapy preceded by acetylsalicylic acid (n = 7) or were treated without thrombolytic therapy (n = 7). The urinary 11-d-TXB2 level in healthy control subjects was 327 +/- 126 pg/mg creatinine. A significant increase was observed in patients with AMI with no difference between those who received no thrombolytic therapy (673 +/- 283 pg/mg creatinine in the first 12 hours) and those who received streptokinase (833 +/- 613 pg/mg creatinine) or rt-PA (836 +/- 653 pg/mg creatinine). Patients pretreated with acetylsalicylic acid had urinary 11-d-TXB2 values ranging between 361 and 155 pg/mg creatinine. A significant difference in 11-d-TXB2 values was observed only when patients who were reperfused were separated from those who remained occluded according to angiographic criteria (1085 +/- 498 vs 391 +/- 227 pg/mg creatinine in the first 12 hours, p less than 0.001). We conclude that reperfusion and not thrombolytic agents per se appears to be the factor that induces platelet activation and consequently facilitates reocclusion.

Aspirin↗
PubMed1992

Buserelin acetate versus expectant management in the treatment of infertility associated with minimal or mild endometriosis: a randomized clinical trial.

OBJECTIVE: We performed a randomized clinical trial to evaluate the efficacy of intranasal 400 micrograms buserelin three times daily for 6 months versus expectant management in the treatment of infertile women with pelvic endometriosis stage I or II of the revised American Fertility Society classification. STUDY DESIGN: Seventy-one consecutive patients (mean age 32 years) were studied at the First Department of Obstetrics and Gynecology, University of Milan, and the Department of Obstetrics and Gynecology, Ospedali Riuniti, Bergamo, between February 1988 and June 1989. Thirty-five women were randomly allocated to buserelin treatment and 36 to expectant management. The baseline distribution of subjects for age, disease stage, and reproductive history was similar in the two groups. All patients were followed regularly; median follow-up was 17 months in the buserelin group and 18 months in the women given expectant management. If pregnancy did not occur within 12 months of randomization, cycles were monitored by ultrasonography and hormone measurements, and when abnormalities were detected clomiphene citrate and human chorionic gonadotropin were administered. RESULTS: A total of 17 pregnancies were observed both in the buserelin-treated patients and in the expectant management group. The 1- and 2-year actuarial overall pregnancy rates were similar in the two groups, 30% and 61% in the former and 37% and 61% in the latter group, respectively. Spontaneous abortion occurred in five of the 17 pregnancies in the women treated with buserelin and in one of the 17 in those managed expectantly; this difference was, however, not statistically significant (chi 1(2) adjusted for disease stage and use of clomiphene citrate and human chorionic gonadotropin treatment = 3.01, p = 0.08). No fetal death or stillbirth was observed. CONCLUSIONS: Our findings suggest that treatment with gonadotropin-releasing hormone agonists is unlikely to have a marked influence on the reproductive outcome of infertile women with minimal or mild endometriosis.

Adult↗
PubMed1992

A simple method for electrical field stimulation of cultured granule cells.

A method suitable for electrical field stimulation of superfused primary cultures of cerebellar granule cells is described. A microchamber of about 0.5 ml was obtained by closing the culture dishes with a perspex plug equipped with stimulating electrodes and inlet-outlet tubing. Two-minute trains of electrical pulses (alternate polarity, 2-ms duration; 100 mA intensity; 10 V drop between electrodes; frequency 5, 10 and 20 Hz) applied to cultures kept at 27 degrees C, elicited a D-[3H]aspartate outflow which was frequency related, [Ca2+]0 dependent, tetrodotoxin sensitive. Moreover 2 trains of 10 Hz pulses (S1 and S2) at 30-min intervals caused an S2/S1 ratio equal or near to one, thus demonstrating that a steady-state condition had been achieved. The NMDA antagonist DL-2-amino-5-phosphonopentanoic acid (AP5) but not the non-NMDA antagonist, 6-cyano-7-nitroquinozaline-2,3-dione (CNQX), added before S2, significantly increased the electrically evoked tritium efflux, suggesting that the endogenous transmitter released during electrical stimulation activated an NMDA-mediated negative feed-back. This technique of electrical field stimulation seems particularly feasible to study the extent and time course of drug effects on spontaneous and evoked D-[3H]aspartate outflow.

2-Amino-5-phosphonovalerate↗
PubMed1992

Changes in gamma-aminobutyric acid release induced by topical administration of drugs affecting its metabolism and receptors: studies in freely moving guinea pigs with epidural cups.

The effect of local application of drugs affecting gamma-aminobutyric acid metabolism and receptors on cortical aminoacid release has been investigated in freely-moving guinea pigs equipped with epidural cups. Topical treatment with gamma-aminobutyric acid reuptake and/or metabolism inhibitors (alone and in combination) produced a slow and progressive increase in cortical aminoacid release. The inhibition of gamma-aminobutyric acid-transaminase with ethanolamino-O-sulphate seemed to be a suitable procedure for enhancing the gamma-aminobutyric acid efflux without interfering with its autoreceptor-mediated negative feedback, tested with the gamma-aminobutyric acid agonist (+/-)baclofen and antagonist phaclofen. A substantial part of the gamma-aminobutyric acid outflowing from the cortex was of neuronal origin since tetrodotoxin halved the basal efflux in the presence of gamma-aminobutyric acid reuptake and/or metabolism inhibitors. These results, considered together, indicate that the epidural cup technique may be a useful approach to study changes in cortical gamma-aminobutyric acid release induced by drugs acting on gabaergic transmission and directly applied on the surface of the cortex.

4-Aminobutyrate Transaminase↗
PubMed1992

Treatment of malignant mesothelioma with epirubicin and ifosfamide: a phase II cooperative study.

From May 1988 to March 1990, 17 consecutive patients with histologically proven malignant mesothelioma were treated with epirubicin 75 mg/sqm i.v. on day 1 and ifosfamide 1.8 gr/sqm/day i.v. from day 1-5. Treatment was repeated every 3 weeks until progression. Fifty-three chemotherapy cycles were administered to the 17 patients treated (median, 3 cycles/patient). No complete responses, 1 partial response, 8 stable diseases and 8 progressions were noted. Toxocity was acceptable and no treatment-related deaths occurred. Actuarial median survival was 6 months. In this study, a combination of full doses of epirubicin and ifosfamide did not prove to be active in malignant mesothelioma.

Adult↗
PubMed1992

Sorption studies of dipotassium clorazepate salt (Tranxène) and midazolam hydrochloride (Hypnovel) in polyvinyl chloride and glass infusion containers.

The compatibilities of dipotassium clorazepate and midazolam hydrochloride with polyvinyl chloride (PVC) bags have been studied and compared with those observed with glass flasks. At room temperature, dipotassium clorazepate showed chemical instability which was independent of the container. At 4 degrees C, dipotassium clorazepate showed no decrease in concentration over 12 h, both in 5% dextrose solution and 0.9% sodium chloride solutions. When stored for longer periods of up to 72 h, a slight decrease not exceeding 5% was observed. The compatibility of midazolam with the PVC bags was found to be good at room temperature. It was slightly better in 5% dextrose solution than in 0.9% sodium chloride solution. High sorption of the drug was observed at pH 7.0 when the primary ring structure is maintained. The results make it possible for the hospital pharmacist to prepare dipotassium chlorazepate salt and midazolam admixtures up to 3 days before administration, provided the former are stocked in a refrigerator and the latter are prepared in dextrose isotonic solutions.

Chemistry, Pharmaceutical↗
PubMed1992

Clonidine inhibition of norepinephrine release from normal and morphine-tolerant guinea pig cortical slices.

Endogenous norepinephrine (NE) release in cerebral cortex slices taken from normal and morphine-tolerant guinea pigs was measured by HPLC. In normal slices, a linear relationship was found between electrically evoked NE release and the log of the frequency of stimulation in the range of 1-20 Hz. The efficiency of the alpha 2-mediated autofeedback was tested by adding the alpha 2-agonist clonidine and the alpha 2 agonist idazoxan. NE release was dose-dependently reduced by clonidine (1 nmol/L-1 mumol/L) and increased by idazoxan (10-100 nmol/L). The inhibition by clonidine was significantly greater at 1 Hz than at 3 Hz, whereas the absolute increase in NE release induced by idazoxan was greater at 3 Hz than at 1 Hz. Morphine at 1 mumol/L (a concentration per se ineffective) shifted to the left the clonidine concentrations able to inhibit NE release at 3 and 1 Hz (1-10 nmol/L), but at both frequencies, the opiate reduced the maximal inhibition induced by clonidine at 1 mumol/L. In slices taken from morphine-tolerant guinea pigs (in the presence of morphine at 1 mumol/L), clonidine (1 nmol/L-1 mumol/L) was ineffective at the stimulation rate of 3 Hz, but it was more active than in normal slices at 1 Hz. Such a response pattern suggests a reduced availability of alpha 2 receptors and an increase in their sensitivity to clonidine. However, chronic morphine treatment did not influence the physiological autoinhibition because the increase in NE release elicited by idazoxan (10-100 nmol/L) at 1 and 3 Hz was the same in normal and in "morphine-tolerant" slices.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Antagonists↗
PubMed1992

Comparison of [3H]choline and D-[3H]aspartate efflux from guinea pig and human neocortex.

The outflow of [3H]choline ([3H]Ch) evoked by electrical field stimulation and the efflux of D-[3H]Asp induced by 35 mM KCl and 1-10 microM ouabain were studied in human and guinea pig cortical slices, kept under identical experimental conditions. [3H]Ch outflow was significantly lower whereas D-[3H]Asp efflux was significantly higher in humans than in guinea pigs. This suggests a different proportion of the two neuronal systems in these two species. Blockade of muscarinic autoreceptors with atropine increased, whereas stimulation of alpha 2 receptors with norepinephrine (NE) reduced, the evoked [3H]Ch outflow to the same extent in human and guinea pig cortical slices. Conversely, NE did not affect ouabain-induced D-[3H]Asp efflux, suggesting that an alpha 2-mediated control is not operative in the glutamatergic cortical structures. Desmethylimipramine, 2-5 microM, was able to increase [3H]Ch outflow through atropine-like mechanisms only in the human. This drug at 20-50 microM inhibited [3H]Ch and D-[3H]Asp efflux in both species, through mechanisms unrelated to its monoamine reuptake blocking properties. Thus, similarities and differences can be detected between humans and guinea pigs with regard to (a) the relative potency of the cholinergic and acidic amino acidergic signals and (b) the modulation of neurotransmitter outflow by drugs acting on auto- and the heteroreceptors.

Animals↗
PubMed1992

A case of familial nesidioblastosis: prenatal diagnosis of foetal hyperinsulinism.

Persistent neonatal hyperinsulinaemic hypoglycaemia due to nesidioblastosis is a rare condition probably transmitted by an autosomal recessive inheritance. Recurrent hypoglycaemic episodes become evident after birth and cause severe neurological damage without intensive treatment. The intrauterine detection of hypoglycaemia and hyperinsulinism in newborns subsequently diagnosed as affected by nesidioblastosis has not yet been reported. We describe a case of familial nesidioblastosis in which an intrauterine diagnosis could be suggested by high levels of insulin and C-peptide and low values of glucose in the amniotic fluid.

Amniocentesis↗