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Biomedical subjects

M Andreoli

Publications and source records attributed to M Andreoli.

At least 37 records · Page 2Linked to original sources
PubMed1997

Diagnosis of thyroid carcinoma.

Despite being one of the most frequent neoplasms occurring in the endocrine system, thyroid carcinoma is, nevertheless, a relatively rare event (0.5-1.5% of all malignant tumours in man); the differentiated forms are the most prevalent and are characterized by a high mean survival rate, whereas the very aggressive forms are rare and prognosis is unfavourable. Diagnostic evaluation of carcinomatous lesions, particularly in the early stages, may give rise to considerable difficulties at a clinical level due to the differentiation of the benign lesions, which are a frequent finding. The traditional clinico-semeiological and instrumental parameters, which, in the past, were used in the assessment of suspected malignancy, should not be considered as markers of malignancy; however, exposure to ionizing radiations during childhood may have a well defined role of risk. Following the recent progress in genetic and molecular studies, it is now possible to exploit genetic-molecular tumor markers and, at present, thyroid medullary carcinoma may be identified also in the absence of clinical evidence, particularly the familial form, thus allowing suitable prophylaxis in those subjects with specific genetic impairment (e.g. preventive thyroidectomy in infancy). Since no discriminating clinico-semeiological parameters are available, considering the aspecificity of scintigraphic findings and the lack of reliability of echographic imaging in providing data which enable us to distinguish a rare neoplastic pattern from the more frequent finding of a benign thyroid mass, fine-needle aspiration (FNA) cytology may today be considered the technique of choice in the screening of the thyroid nodule. Our experience in over 12,000 nodular lesions since 1982, has confirmed that the cytological examination is the most discriminating investigation, diagnostic reliability being far greater than that of traditional techniques. Considering the high frequency of thyroid nodule disease which rarely harbours a carcinomatous lesion, a very scrupulous diagnostic algorithm is mandatory. The FNA cytology, together with morphofunctional and immunological examinations, as well as dynamic exploration of the thyroid hypothalamo-pituitary axis, which allows a nosographic picture of the thyroid nodule disease, provides a more discriminating appraisal for the surgical approach to a single, solitary or prominent nodule.

Carcinoma↗
PubMed1996

Laparoscopic cholecystectomy for recurrent gallstone pancreatitis during pregnancy.

A pregnant patient with gallstone-induced pancreatitis initially responded to medical treatment, but the pancreatitis recurred. Endoscopic retrograde cholangiopancreatography and laparoscopic cholecystectomy were done at 28 weeks' gestation. The remainder of the pregnancy was unremarkable. Although 20 cases of laparoscopic cholecystectomy have been reported for cholecystitis during pregnancy, this is the first report of laparoscopic management of recurrent gallstone pancreatitis in a pregnant patient.

Adult↗
PubMed1996

[Post-operative hypothyroidism].

Hypothyroidism is not a rare condition, since it represents about 10% of thyroid diseases. It is more frequent in women (F/M = 5/1), and in patients older than 60 years of age. Postoperative hypothyroidism is secondary to thyroidectomy, and the incidence varies, with a reported range between 14% and 75%. This may be related to the amount of thyroid removed, the experience of the surgeon, age of patient, the function of remaining thyroid, and duration of postoperative observation. The analysis of our cohort of more than 23,000 thyroid patients showed a prevalence of hypothyroidism of 11.1%. Postoperative hypothyroidism represents about 39.7% of all hypothyroid cases, and 44% of patients underwent surgery. The prevalence is six fold higher in patients over the age of 60. Factors favoring development are the presence of lymphocytic infiltration of the thyroid and a positive serological test for thyroid antibodies. Overt hypothyroidism represented the largest proportion, prevailing in 60% of postoperative hypothyroid patients. In view of the insidious development of postoperative hypothyroidism in some patients, an accurate follow-up should be required, allowing an opportune treatment with LT4.

Adolescent↗
PubMed1995

Molecular basis of estrogen regulation of Hageman factor XII gene expression.

Estrogen therapy has been reported to cause multiple alterations in hemostasis and to increase blood levels of several procoagulants, including Hageman factor [factor XII (FXII)]. Liver FXII gene expression has been investigated in ovariectomized rats, treated or not with 17 beta-estradiol. A 6-fold stimulation of FXII gene transcription was observed in treated compared to untreated animals, indicating that 17 beta-estradiol is able to induce FXII gene expression in vivo. We have recently shown that human FXII promoter contains an imperfect palindrome, 5'-GGGCAnnnTGACC-3', at position -43/-31 resembling the consensus estrogen-responsive element (ERE). Portions of different length of the FXII promoter were fused to the chloramphenicol acetyltransferase (CAT) coding sequence and transiently cotransfected with human estrogen receptor (ER) into NIH3T3 and HepG2 cells in the presence or absence of 17 beta-estradiol. A 230-base pair fragment of FXII promoter, spanning nucleotides - 181/49, conferred a strong estrogen responsiveness to the CAT reporter gene, suggesting that a functional ERE resides in this region. Cognate receptors, such as those for thyroid hormone or retinoic acid, did not stimulate CAT activity. Gel mobility assays demonstrated a specific interaction between ER and the 230-bp FXII promoter fragment containing the putative ERE palindrome. Similar results were obtained when an oligonucleotide spanning the consensus ERE was used; the complex between ER and FXII promoter sequences was supershifted after the addition of an anti-ER monoclonal antibody. Insertion of FXII-ERE into the heterologous thymidine kinase promoter conferred a strong estrogen responsiveness that was abolished by mutations of the 5'-half of the palindrome. These results represent the first demonstration at the molecular level of the regulation of a blood coagulation factor gene by 17 beta-estradiol as well as the first identification of a functional ERE within this class of genes.

Animals↗
PubMed1994

PCR amplification and analysis of ras oncogenes from thyroid cytologic smears.

Fine needle aspiration (FNA) cytology represents a reliable diagnostic procedure for preoperative identification of thyroid carcinoma. For improving its diagnostic accuracy, a technique that allows the analysis of cancer-related gene abnormalities on thyroid FNA smears has been developed. Cells were collected by scraping from thyroid smears, DNA-extracted and ras proto-oncogene sequences amplified by the polymerase chain reaction (PCR). Preliminary destaining of cytologic smears was essential for efficient PCR amplification. Twelve thyroid FNA cytologic smears, characterized by the indeterminate pattern of follicular neoplasia, were analysed for the presence of ras mutations known to confer an oncogenic potential. The same nucleotide substitution at codon 12 of the H-ras proto-oncogene was detected in two different thyroid nodules among six cases that, at final histology, were identified as follicular carcinomas. No ras mutations were observed in the remaining six cases that were diagnosed as follicular adenoma at histologic examination. Molecular analysis of FNA smears may provide additional information on the nature of the lesion underlying thyroid neoplasia, thus improving diagnostic accuracy of conventional FNA cytology.

Adolescent↗
PubMed1993

[The autonomous nodule. Clinical aspects].

Autonomously functioning thyroid nodule (AFTN) includes a wide spectrum of unique or multifocal diseases, either hyper or euthyroid, which share the same independence from thyroid stimulating hormone (TSH) regulation in terms of growth and function. The pathological basis and the recent molecular implications of the disease are briefly discussed. Clinical and epidemiologic data of 1572 patients with AFTN, out of a population of 14107 patients with thyroid diseases, sequentially evaluated from 1974 to 1992, have been retrospectively examined. The mean age of AFTN occurrence is 41 years and it appears more frequently in women (F/M = 5.3/1). Clinical hyperthyroidism occurs only in 17% of patients and is more frequently observed in men over 40 years of age. The presence of sonolucent area inside the nodule is detectable in 8.6% of cases and may be associated with spontaneous arrest of growth. When AFTN is submitted to cytologic evaluation, patterns similar to those observed in nodular goiter are shown (colloid lesion, cyst and nodular hyperplasia). Signs of hyperactivity are also shown by follicular cells. In the presence of a cyst, a fine needle aspiration was performed and a complete resolution was observed in 40% of cases. When cyst recurred after aspiration, a solution of tetracycline was inserted into the cavity. Sclerosing therapy was efficient in evacuating the volume of the nodule in 50% of the cases. Patients with AFTN were followed for a mean period of 61 months and 84.7% of them did not show any morphological or functional change, while the remaining 15.3% of cases became hyperthyroid.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[A Morgagni-Larrey hernia. A case report].

The paper reports a case of Morgagni-Larrey hernia observed by the authors. The etiopathogenesis is described and the importance of surgery is underlined even in asymptomatic cases in order to ensure a benign postoperative outcome.

Female↗
PubMed1991

Effect of extracellular sodium on thyroid hormone uptake by mouse thymocytes.

In mouse thymocytes, a stereospecific saturable energy-dependent and ouabain-inhibitable system facilitates T3, but not T4, entry. We studied here the effect of sodium depletion on cellular uptake of thyroid hormones by mouse thymocytes. Time-course experiments indicated that extracellular sodium depletion reduced [125I]T3 uptake at each time studied. At equilibrium, the removal of extracellular sodium and its substitution with isoosmotic choline decreased saturable [125I]T3 uptake by 60 +/- 10%; this effect was dose dependent. The substitution of sodium with lithium, instead of choline, had no effect on the uptake process. [125I]T4 uptake was lower than that of [125I]T3 and not affected by sodium depletion. The half-maximal effect of sodium deprivation on [125I]T3 uptake was reached at an extracellular sodium concentration of about 40 mM. The variation of external pH influenced T3 accumulation by thymocytes. [125I]T3 progressively decreased from acid to alkaline pH under normal and sodium-depleted conditions; however, the sodium-dependent fraction was more than doubled at physiological pH compared to that at more acidic and more alkaline pH. The sodium ionophore monensin decreased T3 uptake by 51% at a concentration of 20 microM. These results indicated the existence of a sodium-related mechanism of T3 uptake into mouse thymocytes that does not operate for T4 uptake.

Animals↗
PubMed1991

[Hypothyroidism: current clinical, physiopathological and therapeutic aspects].

The correct diagnosis and an appropriate classification of hypothyroidism must be considered on the light of the most recent physiopathological and molecular information. Hypothyroidism is no longer regarded as the rare disease characterized by a myxedematous condition as described since one century ago. With the present improvement of the diagnostic tools the thyroid hypofunction now includes all those blunted forms that are classified as subclinical or latent hypothyroidism. Thus, the hypothyroid syndrome, previously considered a rare event in its overt form, reaches a prevalence of 14% in female aged over fifty years. Following a coherent, concise historical review, the influence of age, surgery, drugs and autoimmunity on the etiology of the disease are critically discussed. The early detection and treatment of congenital hypothyroidism, to avoid an irreversible damage of the central nervous system, by means of the screening on the paper spot is also stressed. Replacement therapy with synthetic levothyroxine has to be personalized, according to the age and other clinical conditions, and should be prescribed also in the treatment of subclinical hypothyroidism.

Adult↗
PubMed1990

Cytofluorometric analysis of lymphocyte subsets in thyroid aspirates from patients with autonomously functioning nodules.

A microscale method, based on two-colour dye immunolabelling and flow sorting cytofluorometry, was used to characterize lymphocyte subsets in thyroid tissue specimens obtained by fine-needle aspiration (FNA) in 21 patients with autonomously functioning thyroid nodule (AFTN) and five patients with cold thyroid nodule (CTN). Inversion of the ratio between CD4+ and CD8+ lymphocytes, due to a relative increase of CD8+ cells, was found among intrathyroidal lymphocytes in AFTN patients. The abnormal lymphocyte subset distribution was not observed in the peripheral blood of the same group of patients. In patients with CTN the lymphocyte subset distribution was normal, both in the thyroid and in the peripheral blood. In AFTN patients, a significant correlation was observed between the decrease of intrathyroidal CD4+/CD8+ ratio and the increase of plasma thyroid hormone levels. Whether the immunological abnormalities found in AFTN could play a pathogenetic role in the clinical presentation and outcome of the disease remains to be established. The FNA-applied micromethod used in this study could be extended as a routine investigation to characterize the immunogenic substrate of thyroid disorders.

Adult↗
PubMed1989

Carrier-mediated [125I]-T3 uptake by mouse thymocytes.

Thyroid hormone entry into the thymocyte, a thyroid hormone target, was investigated by incubating the cells with tracer amounts of [125I]L-T3. At 37 C T3 uptake was linear with time up to 2 min, and then approached a plateau. The specific T3 uptake, obtained by subtracting the uptake in the presence of excess unlabeled T3, represented 48 +/- 6% of the total at equilibrium. Unlabeled L-T4, D-T3, and triiodothyroacetic acid were less effective than L-T3 in reducing [125I]T3 uptake. Kinetic studies on the initial rate of T3 uptake indicated, for the saturable process, a maximum velocity of approximately 1 pmol/10(6) cells.min and a Km of approximately 0.8 nM. Lowering incubation temperature to 4 C resulted in a two thirds reduction of the total T3 uptake. Washout experiments indicated a different hormone release, being more rapid for cells incubated at 4 C than at 37 C; at 30 min 70% of labeled T3 was released when incubation was carried out at 4 C compared to only 35% after incubation at 37 C, indicating the major intracellular location of the hormone at the latter temperature. An energy requirement of T3 uptake in thymocytes was shown by sensitivity to oligomycin; the effect was dose dependent, showing a maximal decrease in specific uptake of 85%. The involvement of cation movement in the entry process of T3 was indicated by the sensitivity to ouabain. These results indicate the existence of a stereospecific, energy-dependent, saturable process for T3 entry in thymocytes.

Animals↗
PubMed1988

Ovarian steroids modulate the action of calcitonin in women.

Slow i.v. infusion of salmon calcitonin into normal women led to a transient increase in plasma concentrations of cyclic AMP and to a decrease in plasma calcium, which was maintained for at least 2 h. These responses were significantly reduced in the same patients after hysterectomy and ovariectomy. In contrast, maintenance of the ovaries at the time of surgery, or substitutive hormonal therapy, seemed to restore the sensitivity to exogenous calcitonin, suggesting a permissive role of ovarian steroids in the effect of calcitonin. The most likely explanation for this phenomenon is that these hormones influence either the number of calcitonin receptors or the coupling of the receptors to the functional unit of bone adenylate cyclase.

Adult↗
PubMed1984

Human undifferentiated thyroid carcinoma synthesizes and secretes 19S thyroglobulin.

Thyroglobulin (Tg) biosynthesis and secretion have been studied in one case of undifferentiated small spindle cell human thyroid carcinoma. From tumor tissue were extracted 32 mg of soluble proteins per gram of wet tissue, compared with 54 mg from control gland; after ammonium sulfate fractionation, density gradient centrifugation, and immunoprecipitation, 1.3 mg of Tg per gram of wet tissue, compared with 31.2 mg from control, were purified. By incubating in vitro up to 3 hours tumor slices with tritiated leucine, galactose, and 125I, the rate of incorporation of leucine and galactose increased with time in tumor tissue. However 125I incorporation into soluble proteins from tumor, at 3 hours of incubation, was only 1.7% of control value. By density gradient centrifugation of labeled soluble proteins a well-separated component sedimenting in the 19S peak was identified. No radioiodine was detected in the 19S fraction which showed the immunoreactive properties of 19S and was poor in 127I and sialic acid. In the incubation medium of tumor were secreted 0.4 mg of 19S Tg per gram of wet tissue compared with 48 mg of tissue in the control gland. Thus the undifferentiated thyroid carcinoma synthesizes a protein with the physiochemical and immunologic properties of 19S Tg. The undifferentiation of thyroid cells does not affect the biochemical steps involved in the synthesis of Tg.

Aged↗
PubMed1982

The isoelectric focusing of human thyroglobulin.

The isoelectric focusing of human thyroglobulin has been studied on slab gels. Three bands, focusing between pH 4.4 and 4.7, are observed. Deglycosylation of thyroglobulin does not affect the distribution of focused bands, but increases the pH range of focusing slightly. Native thyroglobulin and its half-sized subunit show the same distribution of isoelectric bands. Refocusing of one band results in the appearance of the three original bands. It appears that soluble complexes of thyroglobulin with ampholyte account for the apparent heterogeneity observed on isoelectric focusing.

Ampholyte Mixtures↗
PubMed1981

[Effect of change of habitat (sea and fresh water) on in vivo thyroglobulin synthesis in Atlantic glassed eels (Anguilla anguilla L.)].

Thyroid biosynthesis in glassed eels (Anguilla anguilla L.) was studied to establish whether salinity changes could affect it, when they live in sea water or in fresh water containing 125I. Aqueous extrait of homogenized cephalic heads of glassed eels contains an iodinated protein 17-19 S having thyroglobulin-like properties and including iodotyrosins (MIT and DIT) and thyroid hormones (3 and T4). Biosynthesis of this proteins is roughly twice more important in fresh water than in sea water at 19-21 degrees C and its specific radioactivity (125I) is practically double in fresh water.

Acclimatization↗