Search PubMed⌕ Search

Biomedical subjects

S Grasso

Publications and source records attributed to S Grasso.

At least 91 records · Page 5Linked to original sources
PubMed1994

Structure-activity relationships in thienodiazepine and benzodiazepine derivatives.

The structural and electronic characteristics as well as the anticonvulsant properties and benzodiazepine receptor binding of thieno[3,4-b][1,4]diazepine and 1,5-benzodiazepine derivatives are compared and discussed. The data obtained suggest that the electronic rather than the structural properties appear mainly responsible for the variant degree of anticonvulsant activity exhibited by the tested compounds.

Acoustic Stimulation↗
PubMed1994

Aminopyrazinyl derivatives: synthesis and evaluation of antiinflammatory and related activities.

Some amides, 1-substituted methylenediamines and 2-substituted thiazolidin-4-ones, all containing the aminopyrazinyl moiety, were synthesized and tested in the experimental models of acute and chronic inflammations and as potential analgesic agents. The first series of compounds are inactive, whereas the N,N'-di-(2-pyrazinyl)-methylene-diamines and the 3-(2'-pyrazinyl)-thiazolidinones 6, 7, 11, 12 and even more 16 and 17 were found to be endowed with antiinflammatory and analgesic properties and low acute toxicity, the two latter being the most interesting.

Animals↗
PubMed1994

Reduction of spontaneous autoimmune diabetes in diabetes-prone BB rats with the novel immunosuppressant fusidic acid. Effect on T-cell proliferation and production of interferon-gamma.

Diabetes-prone (DP) BB rats spontaneously develop a hyperglycaemic condition which closely resembles human insulin-dependent diabetes mellitus (IDDM), both in terms of clinical and histological features. The incidence of IDDM was significantly reduced when these animals were treated with 2 or 4 mg fusidic acid (FA)/day i.m. from day 30 to day 120 of age. In addition, the mean insulitis score was significantly diminished in the animals treated with FA compared to both vehicle-treated and untreated controls. Finally, 2 mg/day of FA i.m. prevented cell proliferation and interferon-gamma secretion from peripheral blood mononuclear cells upon ex vivo stimulation with concanavalin A. The capacity of FA to substantially reduce the incidence of autoimmune diabetes in a well-known animal model of human IDDM supports previous observations regarding the immunosuppressive properties of FA and its potential use in the treatment of human autoimmune diabetes.

Age Factors↗
PubMed1993

Molecular requirement for anticonvulsant activity in a series of thiazolo-1,4-benzodiazepine derivatives and comparison with classical benzodiazepines.

1. The behavioural and anticonvulsant effects of several thiazolo[3,2-d][1,4]benzodiazepines (TBZ) were studied after intraperitoneal administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures. 2. Anticonvulsant effects on seizures evoked by means of auditory stimulation (109 dB, 12-16 kHz) were evaluated in DBA/2 mice placed singly under a perspex dome. 3. Hypothermic activity was observed after the highest doses of the benzodiazepines studied. 4. In addition, some TBZ were examined for anticonvulsant properties with respect to clonus induced by pentylenetetrazol. 5. Our study demonstrated that some thiazolobenzodiazepine derivatives were more potent than clobazam, desmethylclobazam and chlordiazepoxide, and less potent than diazepam, desmethyldiazepam and alprazolam. 6. In the series of tricyclic benzodiazepines, thiazole nucleus fusion to the "d" edge of the 7-membered ring results in an effective increase of the energy barrier for the heptatomic system reversal, and is probably responsible for, jointly with the lack of C=N double bonds, lower activity with respect to the 1,4-benzodiazepine precursors. 7. The potency of various thiazolobenzodiazepine derivatives as inhibitors of specific [3H]flunitrazepam binding to membranes from cerebellum or hippocampus was evaluated. 8. All tested compounds produced concentration-dependent inhibition of [3H]flunitrazepam binding. 9. The pharmacological activity of TBZ2, the most active compound of this series, was significantly reduced by treatment with flumazenil (2.5 mg/kg i.p.), suggesting clear involvement of a benzodiazepine mechanism in the anticonvulsant activity of these compounds.

Acoustic Stimulation↗
PubMed1993

Quinolones potentiate cefazolin-induced seizures in DBA/2 mice.

The behavioral and convulsant effects of cefazolin, a beta-lactam derivative, were studied after intraperitoneal administration to DBA/2 mice, a strain genetically susceptible to sound-induced seizures, and Swiss mice. DBA/2 mice were more susceptible to seizures induced by cefazolin than were Swiss mice. The proconvulsant effects of some quinolones on seizures evoked by intraperitoneal administration of cefazolin were also evaluated in DBA/2 mice. Our study also demonstrated that the order of proconvulsant activity in our epileptic model was pefloxacin > enoxacin > ofloxacin > rufloxacin > norfloxacin > cinoxacin > ciprofloxacin > nalidixic acid. The relationships between the chemical structures and proconvulsant activities of quinolone derivatives were studied. The relationship between lipophilicity and proconvulsant activity was also investigated.

Animals↗
PubMed1993

Pyrrolo[1',2':1,2]imidazo[4,5-b]pyridines, pyrrolo- [2',1':2,3]imidazo[4,5-c]pyridines and pyrrolo[2,1-f]purines as potential benzodiazepine ligands.

The synthesis of some 7,8,8a,9-tetrahydro-6H-pyrrolo[1',2':1,2]imidazo[4,5-b]pyridin-6-ones, 5,5a,6,7-tetrahydro-8H-pyrrolo[2',1':2,3]imidazo[4,5-c]pyridin-8-ones and 7,8,8a,9-tetrahydro-6H-pyrrolo[2,1-f]purin-6-ones is reported. The structure of the obtained compounds has been assigned by means of 1H-NMR spectra assisted by NOESY measurements. In addition, the ability to displace [3H]-flunitrazepam binding from rat brain membranes is determined. Only the pyrrolopurine derivative 5d binds to the benzodiazepine receptor (BZR) with appreciable potency.

Animals↗
PubMed1992

Modulation of fibrinogen content in cryoprecipitate by temperature manipulation during plasma processing.

In routine blood bank production of single-donation cryoprecipitate, the introduction of a 16-hour hold at 4 degrees C, with the frozen plasma units packed into polystyrene containers, resulted in plasma prethaw temperatures of -4 degrees C to -8 degrees C. This in turn resulted in cryoprecipitate fibrinogen levels that were 214 percent of those obtained when units were thawed immediately after removal from -30 degrees C storage. In scale-model production of factor VIII concentrate, plasma warmed from -30 to -10 to -15 degrees C over 18 hours before pooling and thawing yielded cryoprecipitate fibrinogen levels that were 66 percent of those found in plasma warmed to -2 to -5 degrees C over the same period. Processing -30 degrees C plasma without a warming period led to cryoprecipitate fibrinogen levels that were 40 percent of those obtained from plasma warmed to -2 to -5 degrees C. These differences were accentuated after purification of the cryoprecipitates to an intermediate-purity factor VIII concentrate. These results suggest that simple modifications in production methods allow the fibrinogen content of cryoprecipitate to be tailored to specific uses.

Blood Banks↗
PubMed1992

The effects of deoxyspergualin on the development of diabetes in diabetes-prone BB rats.

The effects of the administration of the recently discovered immunosuppressant 15-Deoxyspergualin (DSP) on the development of insulin-dependent diabetes mellitus (IDDM) in diabetes-prone BB rats were studied. The data show that 2 mg/kg body weight DSP, administered six times a week from the 30th day up to the 105th day of age, significantly reduced the incidence of diabetes in diabetes-prone BB rats as compared with the PBS-injected controls. The drug was also able to reduce the signs of pancreatic insulitis and the percentages of W3/25+ and OX6+ splenocytes. Interruption of the treatment resulted in a later onset of diabetes in a high percentage of animals within 41 days. These findings suggest that 15-DSP may temporarily reverse the pathogenic mechanisms leading to beta cell destruction and autoimmune diabetes in a well-known experimental model of human insulin-dependent diabetes mellitus.

Animals↗
PubMed1992

Gastrin (G) cells are the cellular site of the gastric thyrotropin-releasing hormone in human fetuses and newborns. A chromatographic, radioimmunological, and immunocytochemical study.

In this study we analyzed the ontogeny and location of gastric TRH in human fetuses, preterm and term newborns, and adults. TRH immunoreactive cells were found in the antrum towards the bottom of developing glands and double immunostaining demonstrated that this neuropeptide is coexpressed with gastrin in the same cell (G-cell). In the youngest fetuses studied (12 weeks) G cells were few and contained both gastrin and TRH. They increased in number during development and were most abundant between 26 and 36 weeks of gestation. These morphological data correlated with total immunoreactive TRH content extracted from the whole stomachs of six fetuses and two preterm infants. On the contrary G cells containing both hormones were decreased in the newborn at term and not identified in the adult whereas those containing only gastrin were numerous in both. The TRH extracted was indistinguishable from synthetic TRH using chromatographic, radioimmunologic, and enzymatic criteria. As has already been reported, TRH was found in insulin-containing cells of the islets of Langerhans in the pancreas of our fetuses and newborns. These cells presented a similar development pattern to the gastric G cells.

Adult↗
PubMed1992

[The nonspecific bronchial stimulation test with methacholine and an ultrasonic mist of distilled water: which is to be preferred in the military sphere?].

The authors compare the methacholine (Mch) and the nebulized ultrasonic distilled water (NUDW) bronchial challenge as regard sensitivity and time required to perform them. For military service fitness, were studied 24 asthmatic patients. Each subject performed random a bronchial challenge by Mch (Yan method) and by NUDW (Allegra method) in two different days; for each bronchial challenge has been measured the time required to perform it. The atopic status has been evaluated by skin-prick test. All the subjects have shown a positive response to Mch test (PD 20 FEV1 mean: 352 mcg, range 80-850) whereas 13 subjects (54%) have shown a positive response to NUDW. The time required to evaluate all the subjects by Mch test has been 199.5 minutes whereas the total time required to evaluate all the subjects by NUDW test (127 minutes) and to evaluate by Mch test the non responders to NUDW (100 minutes) has been 227 minutes. The most of subjects were skin reactors. No difference was found as regard onset of disease, basal lung function and atopic status between responders and non responders to NUDW test. We conclude that NUDW test has shown a lack of sensitivity in this sample (50% of asthmatic patients could be misdiagnosed) and that the Mch test is preferable to determine a rapid method for measurement of bronchial responsiveness.

Adolescent↗
PubMed1991

FK-506 prevents diabetes in diabetes-prone BB/Wor rats.

The effect of the immunosuppressant FK-506 on the development of diabetes in BB/Wor rats was investigated. Using a treatment schedule (25 micrograms i.m. from day 27 to 120), not associated with detectable general ill effects, this drug was found to completely inhibit the appearance hyperglycemia and to reduce the histological signs of pancreatic insulitis. The treatment was also able to reduce the percentages of Ia+ T-lymphocytes and to block the appearance of detectable serum levels of gamma interferon (IFN).

Animals↗
PubMed1991

Is alexithymia a non-neurotic personality dimension?

The basic hypothesis of the literature on alexithymia, i.e. that alexithymia has a higher prevalence in psychosomatic than in neurotic (and delusional) patients, was empirically tested by means of the well-validated Toronto Alexithymia Scale (TAS). Surprisingly, neurotic and delusional patients (N = 71) had significantly higher mean total scores on the TAS, compared with the psychosomatic group (N = 150); the normal control sample (N = 224) was, as predicted, the lowest scorer. This hierarchical distribution was confirmed for the first two factors of alexithymia: (1) difficulty in distinguishing between feelings and bodily sensations, and (2) difficulty in expressing feelings. The psychiatric group was, instead, the lowest scorer on the third factor (lack of fantasy life). A substantial cross-validation of the above findings was achieved by comparing on the TAS three subgroups of the normal sample (symptom-free, somatizing and 'neurotic' normal controls). The postulate of the non-neurotic nature of alexithymia, along with its many psychopathological and technical corollaries, is completely contradicted by the present findings.

Adult↗
PubMed1991

The Defense Mechanism Test in nonpsychotic psychiatric outpatients and normal controls.

In the Defense Mechanism Test, stimuli representing a central figure threatened by a peripheral person are presented tachistoscopically, at increasing exposure times. The threat is assumed to trigger defense mechanisms that are expressed by several types of perceptual distortions. Given that to date no experimental study has validated the discriminative power of the Defense Mechanism Test between normal controls and clinical groups, 99 normal controls and 57 nonpsychotic psychiatric outpatients were given the test. Significantly more psychiatric patients than controls were coded for presence of each of the ten main defensive signs of the Defense Mechanism Test (with a peak significance for reaction formation). Ten codings or subcodings of defense which were particularly rare in the control sample were employed to discriminate between groups. This procedure correctly allocated 85.8% of the control subjects and 85.9% of the psychiatric patients. The present findings allow a preliminary distinction between codings of defense with questionable, moderate, or strong clinical significance, in the area of nonpsychotic psychopathology.

Adult↗
PubMed1991

[The measurement of bronchial hyperreactivity for military service fitness].

The authors discuss the efficacy of methacholine challenge to discriminate fit subjects to military service. We evaluated the relation between bronchial hyperreactivity and clinical symptoms, airways caliber and atopic status in a group of italian conscripts who reported to have bronchial asthma. Five-hundred-four subjects were studied. Bronchial hyperreactivity was measured by methacholine test, and atopic status was assessed by skin-tests. A measurable PC20 FEV1 was detected in 424 subjects. On the basis of the methacholine threshold concentration the overall sample was divided in four categories. The four categories differed as regards onset of disease, lung function and skin reactivity towards Dermatophagoides Pter, whereas no difference was found as regards skin reactivity towards Grass. In the group evaluated in spring, the four categories differed as regards skin reactivity towards Grass. In conclusion we found that bronchial hyperreactivity is related to clinical history, lung function and atopic status; the measurement of bronchial hyperreactivity is important to evaluate conscripts referring bronchial asthma.

Adolescent↗
PubMed1990

Glucagon and insulin secretion in low birthweight preterm infants. The effect of glucose infusion.

The effect of the intravenous glucose on plasma levels of glucagon and insulin were evaluated in thirty-five LBW preterm infants who were appropriate for gestational age. Their mean birthweight and gestational age were 1220 +/- 55 g (range 750-1730 g) and 29 +/- 1 weeks (range 25-35 weeks), respectively. A 30 min glucose infusion in 16 infants (1 g/kg b.w. in 30 min) caused a prompt and sustained suppression of plasma glucagon and a delayed but significant insulin release. The mean of the sum of maximal plasma glucagon decrements below the baseline was 173 +/- 42 pg/ml. In another 12 infants a significant fall in plasma glucagon and a variable but significant plasma insulin release also occurred throughout the 24 h study on continuous intravenous glucose (rate 2.4-2.7 mg/kg/min). The mean of the sum of maximal plasma glucagon decrements below the baseline up to 12 h was 282 +/- 36 and was similar to that seen in the previous group.

Blood Glucose↗