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Biomedical subjects

A Ambrosini

Publications and source records attributed to A Ambrosini.

At least 91 records · Page 5Linked to original sources
PubMed1985

Tumor promoter phorbol 12-myristate, 13-acetate inhibits phosphoinositide hydrolysis and cytosolic Ca2+ rise induced by the activation of muscarinic receptors in PC12 cells.

Preincubation of PC12 cells (used both before and after differentiation by NGF) with phorbol myristate acetate (PMA) was without effect on the basal concentration of inositol phosphates (metabolites of phosphoinositide hydrolysis) and of free cytosolic Ca2+, but inhibited considerably the increases induced by the cholinergic agonist carbachol via the activation of the muscarinic receptor. Inasmuch as binding was unaffected, this inhibition might occur at the level of receptor coupling to its transduction mechanism(s). Inhibition appeared within 1 min and was maximal after 3 min. The concentrations of PMA needed (10(-9)-10(-8)M) were in the range believed to cause specifically the activation of protein kinase C. The muscarinic receptor, via the hydrolysis of phosphoinositides and the generation of diacylglycerol, participates in the regulation of the latter enzyme. Our data suggest therefore that the receptor operates under stringent feedback control by the metabolites generated as a consequence of its activation.

Animals↗
PubMed1985

Muscarinic receptor-induced phosphoinositide hydrolysis at resting cytosolic Ca2+ concentration in PC12 cells.

In PC12 cells, cultured in the presence of nerve growth factor to increase their complement of muscarinic receptors, treatment with carbachol induces muscarinic receptor-dependent rises in free cytosolic Ca2+ as well as hydrolysis of membrane phosphoinositides. Experiments were carried out to clarify the relationship between these two receptor-triggered events. In particular, since inositol-1,4,5-trisphosphate (the hydrophilic metabolite produced by the hydrolysis of phosphatidylinositol-4,5-bisphosphate) is believed to mediate intracellularly the release of Ca2+ from nonmitochondrial store(s), it was important to establish whether it can be generated at resting cytoplasmic concentration of Ca2+ (approximately 0.1 microM). Cells incubated in Ca2+-free medium were depleted of their cytoplasmic Ca2+ stores by pretreatment with ionomycin. When these cells were then treated with carbachol, their cytosolic concentration of Ca2+ remained at the resting level, whereas inositol-1,4,5-trisphosphate generation was still markedly stimulated. Our results demonstrate that an increase in the concentration of cytosolic Ca2+ is not a necessary intermediate between receptor activation and phosphoinositide hydrolysis, and therefore support the second-messenger role of inositol-1,4,5-trisphosphate.

Animals↗
PubMed1984

Topical testosterone propionate in the therapy of vulvar dystrophies.

187 patients with atrophic, hypertrophic and mixed vulvar dystrophy were treated with 2% testosterone propionate ointment from 18 months to 7 years. Symptoms, macroscopic, and histologic picture were evaluated before and during treatment. About 75% of the patients achieved good and excellent symptom relief. Treatment efficacy differentiates according to the type of dystrophy, and in relation to the lesion's extension and the duration of symptoms, which consist mostly of pruritus. Side effects from therapy were negligible.

Administration, Topical↗
PubMed1984

Vulvar lesions at risk. Prevention, clinical methodology and therapy.

In confronting the problem of prevention and early diagnosis of vulvar lesions at risk, the diagnostic methodology for their recognition and the therapeutic measures best taken are discussed. Through the use of routine, ambulatory screening tests, it is possible to detect and recognize those pathological situations which may evolve towards neoplasia. Among these, the vulvar dystrophies, some viral infections and sexually-transmitted diseases are particularly at risk. Patients with oncologic precedents are also at risk as well as patients receiving immunosuppressive therapy.

Female↗
PubMed1983

New trends for pain relief in gynaecologic oncology.

In pre-terminal and terminal gynaecological patients with persistent cancer pain, now it is possible to carry out some anthalgic methods associated or not to parenteral administration of non-narcotic or narcotic analgesic, i.e. intrathecal neurolytic injections and epidural narcotic administration. Many favourable results have been obtained by means of single or repeated 7% phenol in glycerine injections to patients with advanced but not terminal cancer affected by somatic and segmental pain or by perineal pain. In order to control more extensive pains, epidural injections of morphine in saline have been employed in preterminal patients. This method appears to be the best answer to many problems complained by the patients: pain, depression, malaise. As a matter of fact, low doses of epidural morphine induce both complete pain relief and sedation or slight drowsiness.

Autonomic Nerve Block↗
PubMed1983

Hormone receptors in dystrophic and neoplastic vulvar disease. Preliminary considerations.

Hormone receptor assays for testosterone, estrogens and androgens were performed on 53 biopsy specimens of vulva from 40 patients, consisting of 6 with normal tissue, 14 with atrophic type dystrophy, 13 with hypertrophic type dystrophy, and 20 with malignancy. Atrophic and hypertrophic forms showed a different receptor pattern; hypertrophic forms were characterized by consistently higher levels of progesterone receptors not correlated with estrogen receptors. Neoplastic tissue showed no significant changes in values compared to normal or dystrophic forms, but range of variability was high. The bond between neoplastic forms and hormone activity seems without doubt less important than in the corresponding endometrial and mammary forms. The study of dystrophic forms, instead, should be further explored with a larger number of cases.

Adult↗
PubMed1983

Vulvar carcinoma: natural history.

On the basis of our clinical experience and a careful revision of the literature, we have attempted to identify the natural history of vulvar carcinoma by verifying the real evolutive possibility of these lesions, their possible genesis, the latent period between pre-invasive and invasive forms, and some events which seem to play a significant role in the onset of the invasive form in this period. These considerations indicate a new clinical and study approach to carcinoma in situ, which would thus become a pathology characterized by a more precise pathogenetic and evolutive individuality.

Carcinoma in Situ↗
PubMed1982

Paget's disease of the vulva: diagnostic and therapeutic problems.

Two cases of Paget's disease of the vulva are presented and the complex problem of diagnosis of this neoplasia is evaluated: all the diagnosis tests used in vulvar disease (vulvar citology, toluidine blue test) are insufficient in the presence of on eventual underlying carcinoma. In view of these considerations, the therapeutic approach is total vulvectomy.

Adult↗
PubMed1982

[Chemical and pharmacological research on pyran derivatives. XV. Phenyl-substituted 2-(dialkylamino)chromones].

Some 2-(dialkylamino)chromones phenyl substituted in position 6 or 7 or 8 were synthesized by reaction of N,N-dialkylethoxycarbonylacetamides with 4- or 3- or 2-biphenylol, respectively, in the presence of phosphorus oxychloride. The pharmacological activity of these compounds was then evaluated and compared with that shown by naphthopyran derivatives of structures (I), (II), and (III). With this same purpose also 6- and 8-benzyl derivatives of 2-(dialkylamino)chromones were prepared by using in the reaction 4- or 2-benzylphenol. Pharmacological screening showed that 6-phenyl substituted 2-(dialkylamino)chromones maintained the antireserpine and antimetrazole acti-activities which were possessed by the 1H-naphtho[2,1-b]pyran derivatives (I) and the 4H-naphtho[2,3-b]pyran derivatives (II), whereas 7-phenyl substituted compounds were devoid of any activity. 8-Phenyl substituted 2-(dialkylamino)chromones maintained to some extent the antiamphetamine activity which was clearly shown by the 4H-naphtho[1,2-]pyran derivatives (III). Furthermore, the compounds bearing the benzyl substituent both in the 6 or 8 position showed only antimetrazole activity.

Animals↗
PubMed1982

Plain films of the abdomen in term pregnancy.

Plain films of the abdomen taken during pregnancy at term from 1971 to 1981 at the Radiology Service of the Obstetric and Gynecological Clinic of the University of Padua are summarized and analysed. The average frequency of X-ray investigation is 0.5%, ranging from 0.06% (in 1980) to 2.11% (in 1977), compared to Carmichael's data which range from 11 to 30%. Indications have remained fairly constant over the years, in view of the very low incidence of this examination. The most significant finding is the greater incidence of fetal malformation in recent years, and is explained by a more efficacious program of pregnancy screening. X-ray examination may be still employed in some cases to obtain superior information regarding the best definition of gestational age, some fetal malformation, and in rare cases, hemolytic disease.

Congenital Abnormalities↗
PubMed1982

Multiple tumors of the female genital tract.

The increased incidence of multiple primary tumors of genital-breast district has been evaluated, with the possibility of early diagnosis which consent greater survival in cancer patients. We found a particular high incidence of second neoplasia associated with vulval tumors (7.4%). With regard to pathogenetic factors, the oncogenic role of certain treatments is undoubtedly important, especially if they are protracted in time. It is necessary that these patients undergo complete gynecological screening for a time period that is much longer than that held sufficient to consider a patient cured.

Adult↗
PubMed1982

Vulvar neoplasias in patients with previous cancer history.

The presence of second neoplasia in association with vulvar neoplasia is significant. We confirm the usefulness of including a screening procedure for vulvar neoplasia in the follow-up of patients with gynecological cancer, especially those with carcinoma of the portio. Patients with a first gynecological neoplasia who present vulvar viral infection, or dystrophies, or who have undergone radiotherapy or immunosuppressive treatment are considered at high risk.

Aged↗
PubMed1981

Cardiotocographic modifications during continuous epidural anaesthesia in labour.

Cardiotocographic variations certainly attributable to epidural anaesthesia were studied over the period 1972-1980 on 716 patients in labour. Transitory side-effects due to both direct and indirect action of local anaesthetics appeared in 1.4% of the cases, without, however, subsequently creating any particular foeto-newborn problem. On the basis of the experience acquired, it seems justifiable to affirm that the correct use of continuous epidural block, affected by very small doses of bupivacaine (10-20 mg per administration) is almost risk-free. The only inconvenience therefore that may sometimes arise would only be due to the relevation of a concealed cava occlusion when the maintenance of a left lateral position is not observed.

Adult↗