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Biomedical subjects

C Moretti

Publications and source records attributed to C Moretti.

At least 91 records · Page 5Linked to original sources
PubMed1987

Nuclear antigens differentially expressed during early development of Drosophila melanogaster.

To obtain specific immunological probes for studying molecular events involved in gene activation during early development of Drosophila, we have produced monoclonal antibodies directed against nuclear proteins differentially expressed in time and space during embryogenesis. Twenty-five antibodies against nuclear antigens detected after the onset of zygotic genome transcription were obtained. These antigens have been distributed into six categories depending on their reactivity in dot-blot, in Western-blot and in immunofluorescence on embryo frozen section assays. Six antigens (fifth and sixth categories) are stage-, but not tissue-specific and are present in all nuclei of the embryo after the blastoderm stage. Ten antigens, the third and fourth categories, did not react on immunofluorescence and have not been characterized for a possible tissue specificity. Antigens of the first and second categories are stage- and tissue- specific. Two of them are of particular interest. The first (250 kd, recognized by the monoclonal antibody GB7) is preferentially expressed in nuclei of the ventral nerve cord, whereas the other (65 kd, recognized by the monoclonal antibody LA9) is located in nuclei of the gut and associated structures.

Animals↗
PubMed1986

Long-term prognosis of patients with lacunar syndromes.

A follow-up study of 107 patients with lacunar syndromes has been performed using the analysis of the survival curves and the recurrence curves for new focal cerebrovascular acute episodes. At the end of the 7th year of follow-up, the survival rate of lacunar patients was 479 per 1000, lower than the survival rate of the normal population matched for sex and age (755 per 1000). A more severe prognosis was observed in subjects over 65 years of age, in patients with pseudobulbar syndrome, hypertension and higher degree of disability. The average recurrence rate for new cerebrovascular episodes was 4.74 per 100 patient-years, much lower than that in survivors from cerebral infarction.

Age Factors↗
PubMed1986

Evidence for the presence of specific receptors for N-formyl chemotactic peptides on human spermatozoa.

Synthetic N-formylated peptides are potent chemoattractants for human spermatozoa in vitro. The specific structure-activity relations for eliciting a chemotactic response and the ability of the antagonist tertbutoxycarbonyl-phenylalanyl-leucyl-phenylalanyl-leucyl- phenylalanine (Boc-Phe-Leu-Phe-Leu-Phe) to inhibit the chemotaxis induced by these peptides strongly suggest the presence of receptors on human spermatozoa. The following studies were performed to identify specific binding sites on human spermatozoa by using [35S]-N-formyl-methionyl-leucyl-phenylalanine [( 35S]f-Met-Leu-Phe), a potent chemotactic peptide. Binding of the [35S]formyl-peptide to human spermatozoa was rapid (t1/2, 8 min) and reversible. Binding isotherms of the saturation experiments revealed a single class of high affinity, low capacity binding sites (equilibrium dissociation constant, 17.7 nM; maximal binding, 109 fmol/2 X 10(6) cells) and an average number of 60,000 receptors per cells. The biological potencies of a series of formyl peptides as chemoattractants correlated closely with their relative abilities to compete with [35S]f-Met-Leu-Phe for specific binding to human spermatozoa. These data fulfill the major criteria for demonstration of specific receptors for chemotactic peptides on human spermatozoa. It is likely that these receptor sites initiate the chemotactic response of human spermatozoa to N-formyl peptides.

Adult↗
PubMed1985

Naloxone increases bioactive LH in man: evidence for selective release of early LH pool.

Opioid peptides inhibit LH secretion and the opiate antagonist naloxone provokes increases in plasma LH levels by release of endogenous GnRH from the hypothalamus. To explore the effect of endogenously released GnRH on the mobilization of bioactive LH pools, the bioactive LH response to a single iv bolus dose of 20 mg naloxone has been evaluated and compared to the immunoactive pattern of the hormone in eight young normal male volunteers. Blood samples were withdrawn at 15, 30, 45, 60, 90, 120 min after naloxone injection and LH levels were measured by RIA and rat interstitial cell testosterone (RICT) bioassay. A significant increase in both bio and immuno active LH was observed in all subjects after 15-30 min (p less than 0.05 to p less than 0.001), reaching maximal levels at 30-60 min for both forms of the hormone. The time course of the bioactive LH response magnified the immunoactive LH pattern, and the maximum fold increases were 1.4 and 1.3 fold (62.4 +/- 5.5 SE and 25.0 +/- 3.7 SE mIU/ml) from basal bio and immuno LH levels of 25.9 +/- 4.3 SE and 11.1 +/- 2.0 SE mIU/ml respectively. An early single peak response of bio and immunoactive LH was observed in six subjects while a biphasic pattern was observed in two subjects with a clearly defined and prominent early pool followed by a second pool of higher magnitude. Both bio and immunoactive LH levels began to decline at 45-60 min, but in most subjects remained significantly elevated by about 30% above the basal values at 120 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

ACTH, beta-endorphin and met-enkephalin: peripheral modifications during the stress of human labor.

We investigated the psychoneuroendocrine and emotional correlates of the natural stress situation of human labor. State anxiety, subjective pain, plasma ACTH, peripheral plasma beta-lipotropin (Beta-LPH), beta-endorphin (Beta-EP), and met-enkephalin (Met-Enk) were serially evaluated at six predetermined time points before, and after labor in a sample of 14 women with normal pregnancies. State anxiety and subjective pain showed a progressive increase during labor, with a levelling during the final stage. Plasma Beta-EP and ACTH showed a similar progressive increasing from baseline until the end of labor. Beta-LPH showed no significant modification. Met-Enk remained at nearly baseline values throughout labor, with a marked progressive rise in the postpartum stage. The findings of this study seem to confirm the role of plasma Beta-EP as a stress hormone. Possible relationship between pain and anxiety curves and plasma Beta-EP are discussed in light of psychobiological studies on stress, the opioid system and analgesia. Plasma Met-Enk, according to our findings, should probably not be regarded as a stress hormone. Its rise in the postpartum stage might be as one of the psychoneuroendocrine mechanisms maintaining elevated prolactin levels during lactation.

Adrenocorticotropic Hormone↗
PubMed1985

Human semen inhibits T rosette formation through an opiate mediated mechanism.

Seminal plasma contains high levels of opioid peptides and both seminal plasma and endogenous opioids can influence the immune system. In order to investigate whether these two findings can be related, semen was collected from 7 normal subjects, and assayed for beta-endorphin content and for its in vitro ability to inhibit the total T rosette formation of human lymphocytes in the presence or in the absence of 10(-6) M naloxone, an universal opiate antagonist. The results were as follows: 1) immunoreactive beta-endorphin content in seminal plasma was 4 to 12 times higher than the peripheral plasma levels detected in the same subjects (76.1 +/- 42.1 SD vs 10.5 +/- 2.0 SD pg/ml); 2) increasing concentrations of seminal plasma (1%, 5%, and 10%) in RPMI 1640 significantly depressed the T rosette formation ability of lymphocytes; and 3) the simultaneous addition to the incubation mixture of 10(-6) M naloxone prevented the phenomenon, while naloxone per se was ineffective. The possibility that endogenous opioids may play a role in the immunomodulatory action of human semen is suggested.

Adult↗
PubMed1984

Salmon calcitonin inhibits human sperm motility in vitro.

We have evaluated by a stroboscopic technique the in vitro effect of salmon calcitonin and human calcitonin on the motility of human migrated spermatozoa. We report here that human calcitonin is uneffective while salmon calcitonin is a potent inhibitor of the sperm motility. This salmon calcitonin action is abolished by the preincubation of the peptide with an anti-salmon calcitonin antiserum, demonstrating the specificity of the effect. In addition, we provide evidence that the release of intracellular calcium represents a necessary step for the action of the peptide. In fact, the salmon calcitonin effect is prevented in a dose-dependent way by dantrolene sodium which inhibits the release of calcium from intracellular stores while the calcium channel blocker verapamil is unefficacious. These results suggest a potential role for calcitonin in regulating human sperm motility.

Adult↗
PubMed1984

In vitro interaction between calcitonin and calmodulin.

The effects of salmon calcitonin and human calcitonin on the fluorescence spectra of a fluorescent conjugate of calmodulin with dansyl-chloride and on the calmodulin mediated activation of phosphodiesterase have been studied. We showed that salmon calcitonin provoked calcium-dependent modifications of the spectra of dansyl-calmodulin and completely inhibited the calmodulin mediated activation of phosphodiesterase with a maximum effect at the dose of 5.8 X 10(-7)M and 10(-7) M respectively. No appreciable effect of human calcitonin was observed in either system. This interaction of salmon calcitonin with calmodulin is similar to the interaction of certain neuropeptides and antipsychotic drugs to calmodulin and may explain certain of the peptide's pharmacological effects.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1984

Naloxone fails to increase LH levels in clomiphene treated men.

The gonadotrophin response to the opiate antagonist naloxone administered per infusion has been investigated before and after 5 days of clomiphene treatment in 5 male subjects. Before clomiphene treatment, naloxone caused a significant increase in LH levels, however, after clomiphene, naloxone failed to induce the same effect. An important role for gonadal steroids on the opiatergic inhibitory tone of LH secretion in man is suggested.

Adult↗
PubMed1984

Lack of endogenous opioid inhibitory tone on LH secretion in early puberty.

Thirteen normal children, seven males and six females, during early puberty (I-II according to Tanner), have been studied. Each subject was injected at weekly intervals and in random order with 100 micrograms of LHRH, 0.2 mg/kg of naloxone and 0.9% saline in single bolus. The gonadotrophin response was evaluated. The administration of naloxone failed to elevate LH levels in any of the subjects studied, even in those who showed a clear gonadotrophin response to LHRH. Unlike the response noted in adults, endogenous opiates do not appear to exert a tonic inhibitory influence on LH secretion during early puberty.

Adolescent↗