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Biomedical subjects

F Pacini

Publications and source records attributed to F Pacini.

At least 55 records · Page 3Linked to original sources

Assay of thyroglobulin in serum with thyroglobulin autoantibodies: an unobtainable goal?

Measurement of thyroglobulin (Tg) in serum with anti-Tg autoantibodies (TgAb) represents a difficult challenge. Immunoradiometric assays (IRMA) employing monoclonal anti-Tg antibodies not cross-reacting with endogenous TgAb have recently been developed and proposed for Tg assays in TgAb-positive sera. The aim of the present investigation was to assess the clinical reliability of this approach. Assays of serum Tg in patients with and without TgAb using one such monoclonal antibody IRMA (Thyroglobulin IRMA-Pasteur; IRMA-1) were compared with those obtained by a conventional IRMA employing polyclonal anti-Tg antibodies (HTGK-Sorin; IRMA-2). Preliminary studies for assessment of the interference of TgAb showed that the recovery of added Tg was significantly higher (P < 0.01) when determined by IRMA-1 (64.6 +/- 23%) than by IRMA-2 (49.5 +/- 20%). Study groups included 79 patients with differentiated thyroid carcinoma (DTC) treated by total thyroidectomy and radioiodine ablation; 24 had no metastases or residual thyroid tissue, 31 had a thyroid residue, and 24 had metastatic disease. Seventy-five patients with autoimmune thyroid disease (47 with Graves' and 28 with Hashimoto's disease) were also included. In TgAb-negative sera from DTC patients, similar Tg concentrations were found by both IRMA, i.e. undetectable in most patients with no residual thyroid or neoplastic tissue, low to moderately elevated in the majority of those with residual thyroid tissue, and markedly elevated in all patients with metastatic disease. Serum Tg was undetectable by both assays in several TgAb-positive sera from DTC patients with residual thyroid tissue or metastatic disease, respectively, in whom a detectable or even high serum Tg concentration was expected. Despite the lower in vitro interference of TgAb in IRMA-1, there was no difference between the two assays. In the group of patients with thyroid autoimmune disease, serum Tg concentrations were found to be high in TgAb-negative sera and much lower in TgAb-positive sera by both IRMAs. In conclusion, the present study demonstrates that the use of a monoclonal antibody IRMA for serum Tg, although less susceptible to in vitro TgAb interference, does not necessarily provide any substantial advantage with respect to a conventional polyclonal IRMA in detecting Tg in TgAb-positive sera. The finding of undetectable or lower than expected serum Tg by either method in TgAb-positive serum may well reflect a truly reduced serum Tg concentration. This might be due to an accelerated Tg metabolic clearance in the presence of TgAb.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent

Identification of the Cys634-->Tyr mutation of the RET proto-oncogene in a pedigree with multiple endocrine neoplasia type 2A and localized cutaneous lichen amyloidosis.

Following the recent identification of specific germline mutations of the RET proto-oncogene in Multiple Endocrine Neoplasia type 2A (MEN2A) patients, we looked for mutations of this gene in a pedigree showing recurrence of MEN2A and localized Cutaneous Lichen Amyloidosis (CLA). Basal calcitonin and/or pentagastrin test performed in all the 10 available members of this pedigree confirmed the clinical diagnosis and allowed the presymptomatic identification of an additional carrier. A cys634-->tyr missense mutation, already reported as causative in MEN2A patients, was identified after SSCP analysis and direct sequencing of exon 11 of the RET protooncogene in one individual affected with both MEN2A and CLA, thus suggesting a common etiology for the two disorders. Taking advantage of the observation of an RsaI restriction site in the sequence surrounding the mutated codon, we could demonstrate that the same mutation is present in three other affected members, in the presymptomatic carrier and in one additional 25 years old healthy member who shows a mildly positive pentagastrin test.

Amyloidosis

Serum soluble interleukin 2 (IL-2) receptor (sIL-2R) in differentiated thyroid carcinoma.

Increased concentrations of serum soluble interleukin-2 (IL-2) receptor (sIL-2R), a marker of T-lymphocyte activation, have been found in several metastatic solid tumors. To our knowledge, no information is available on serum sIL-2R in differentiated thyroid carcinoma (DTC). Aim of this study was to evaluate whether disease activity and/or thyroid status may affect circulating sIL-2R in DTC, since it is has recently been demonstrated that serum thyroid hormone concentration positively modulates circulating sIL-2R. DTC patients were divided into 3 groups: Group A: 48 patients without metastases or local recurrences; Group B: 16 patients with cervical lymph node metastases; Group C: 22 patients with distant metastases. All patients were evaluated after total thyroidectomy both off and on L-thyroxine (L-T4) therapy. Control group was composed by 20 healthy euthyroid subjects. sIL-2R was assayed by solid-phase ELISA. In the hypothyroid state, sIL-2R levels of Group A were significantly lower when compared to normal controls (256 +/- 130 vs. 461 +/- 186 U/ml, p < 0.001 by Student t test); Group B and Group C patients off L-T4 therapy had sIL-2R concentrations significantly higher (479 +/- 407 U/ml, Group B; 519 +/- 746 U/ml, Group C) when compared to hypothyroid patients of Group A (p < 0.01 and p < 0.05, respectively), but not significantly different from normal euthyroid controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma, Follicular

Expression of p21 ras protein as a prognostic factor in papillary thyroid cancer.

We studied the expression of p21, the ras encoded protein, in primary tumour of 45 patients with papillary thyroid cancer (PTC). Patients were grouped according to outcome so that one group (31 patients) had a good outcome and the other (14 patients) a fatal outcome, after a follow-up of at least 5 years. The presence of p21 ras protein was assessed by immunohistochemistry with a specific monoclonal antibody (MAb Y-13259). The results were correlated with the outcome, with the expression of proliferating cell nuclear antigen (PCNA)/cyclin (as a marker of cell proliferation) and with other well established prognostic factors for PTC (age, grading, extension and tumour size; Endocrinol Metab Clin North Am 1990, 19, 545-576). p21 staining in tumours of living patients was negative in 15, weakly positive (1+) in 10 and strongly positive (2+ or more) in 6 patients. In tumours from deceased patients, p21 staining was negative in 1, weakly positive in 2 and strongly positive in the remaining 11 patients (P < 0.001, chi 2). PCNA immunostaining was increased in 63.6% (7/11) of the tumours from deceased patients compared to 17.8% (5/28) of the tumours of living patients, but no direct correlation was found between p21 and PCNA expression. Among the other prognostic factors studied, only age > or = 40 years was a significant predictor of poor outcome. The survival curve of patients with strongly positive p21 staining was similar to that of patients aged > or = 40 years at the time of diagnosis. The combination of p21 > or = 2+ and age > or = 40 was superior to age alone (P < 0.05) as a prognostic indicator of poor outcome. In conclusion, our results indicate that the p21 product of the ras (proto)oncogene is differently expressed in PTC, in relation to the degree of aggressiveness. Regardless of the pathogenetic role of the ras oncogene in thyroid tumorigenesis, our data indicate that the expression of the p21 ras protein may be regarded as a prognostic indicator in PTC. Furthermore, overexpression of p21 ras protein is associated with patients in the older age groups, and might contribute to the poor prognosis of elderly patients.

Adolescent

Disappearance rate of serum calcitonin after total thyroidectomy for medullary thyroid carcinoma.

We studied the half-life of serum calcitonin (CT) in patients subjected to total thyroidectomy for medullary thyroid carcinoma (MTC). One patient showed a rapid serum CT component with a half-life of 3 hours and a slow component with a half-life of 30 hours; in another case only the 30-hour component was found. By chromatography of tumor extracts, we found that all the immunoreactive CT had a molecular weight of 3,600. After surgery, normalization of serum CT was achieved within 15 days in 4 patients, at 3 months and at 6 months in 2 other patients, while 1 patient never normalized. Normalization of serum CT after surgery is not an index of definitive cure in MTC, as demonstrated by one patient who relapsed 3 months after normalization of serum CT. However, as a general rule, patients who reach undetectable serum CT levels soon after surgery, are those having the best prognosis.

Adult

Routine measurement of serum calcitonin in nodular thyroid diseases allows the preoperative diagnosis of unsuspected sporadic medullary thyroid carcinoma.

To assess whether routine measurement of serum calcitonin (CT) could improve the preoperative diagnosis of sporadic medullary thyroid carcinoma (MTC), 1385 consecutive patients presenting for nodular thyroid disease during the year 1991 were submitted to serum CT determination and fine needle aspiration cytology (FNAC). The clinical diagnosis was nontoxic nodular goiter in 1197 (86.4%) patients, toxic multinodular goiter in 65 (4.7%), autonomously functioning thyroid nodule (AFTN) in 64 (4.6%), and autoimmune thyroid disease (Graves' disease or Hashimoto's thyroiditis) with nodule(s) in 59 (4.3%). As controls, 177 patients with nonnodular thyroid disease and 32 normal subjects were also studied. Patients with FNAC suspicious of any kind of thyroid carcinoma and patients with elevated basal and pentagastrin-stimulated serum CT, regardless of the results of FNAC, were submitted to surgery. Eight (0.57%) patients (7 with nontoxic nodular goiter and 1 with AFTN) had elevated basal serum CT levels, ranging between 55-10,000 pg/mL. The pentagastrin test was abnormal in all of them. FNAC was suggestive of MTC in 2, thyroid carcinoma in 1, benign nodule in 3, and inadequate in 2. By histology, immunohistochemistry, and Northern blot analysis of total tumor RNAs, MTC was confirmed in all patients, including the 1 with AFTN, who had the association of microfollicular adenoma and a small MTC in the same lobe. After surgery, serum CT decreased to undetectable levels in 7 patients and remained undetectable in 6 of them during a mean follow-up of 22 months, although 1 of them had a positive response to pentagastrin. Forty-four patients in the group with normal serum CT levels had FNAC suspicious for differentiated thyroid carcinoma and were treated by surgery. Differentiated thyroid carcinoma, mostly papillary, was confirmed at histology in 43 subjects (3.1% of all thyroid nodules). In conclusion, the results of our study indicate that serum CT measurement is useful for the screening of sporadic MTC in patients with thyroid nodule(s). The prevalence of MTC, diagnosed by serum CT measurement in a 12-month period, among an unselected series of 1385 patients with nodular thyroid disease was surprisingly high: 0.57% of all thyroid nodules and 15.7% of all thyroid carcinomas. Serum CT measurement was superior to FNAC in suggesting the diagnosis of MTC and was devoid of falsely positive results. Increasing the diagnostic accuracy helped the surgeon to perform more radical treatment of MTC, thus achieving frequent normalization of postoperative serum CT levels. Whether this result indicates definitive cure remains to be established on the basis of longer follow-up.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent

Expression of thyrotropin receptor (TSH-R), thyroglobulin, thyroperoxidase, and calcitonin messenger ribonucleic acids in thyroid carcinomas: evidence of TSH-R gene transcript in medullary histotype.

We studied the expression of the TSH receptor (TSH-R), thyroglobulin (Tg), thyroperoxidase (TPO), and calcitonin (CT) genes in a total of 53 tissues from 30 patients with thyroid carcinoma and from 9 patients with benign thyroid diseases. By Northern blot analysis of total RNA preparations, CT mRNA was expressed in all cases (n = 6) of medullary thyroid carcinoma (MTC). Surprisingly, 3 of them expressed the TSH-R mRNA, in association with the Tg and TPO mRNAs in 1. The presence of the TSH-R transcript in the neoplastic C-cells was confirmed in 1 MTC by in situ hybridization using a mixture of 3 oligonucleotide probes derived from dog TSH-R cDNA. With various degrees of expression, all differentiated thyroid carcinomas (20 papillary and 2 follicular) expressed TSH-R, Tg, and TPO, but not CT mRNAs. On the contrary, samples from 2 patients with anaplastic carcinoma did not express TSH-R, Tg, or TPO mRNA, but 1 of them expressed CT mRNA. All of the transcripts obtained from thyroid carcinomas (both primary and metastatic) were of the same size as the transcripts from normal or benign thyroid tissues, with the exception of 2 cases of differentiated thyroid cancer, in which TSH-R mRNA of lower mol wt (approximately 4.0 kilobases) was found in the absence of alteration in cDNA size and restriction map. The main conclusions of our study are that 1) the TSH-R gene is expressed in some MTC, which supports, at molecular level, the hypothesis of the existence of mixed follicular-medullary thyroid tumors; and 2) the expression of TSH-R, Tg, and TPO in undifferentiated thyroid cancer is lost.

Blotting, Northern

Intermittent versus continuous 5-aminosalicylic acid treatment for maintaining remission in ulcerative colitis.

We performed a 12-month clinical trial to compare the relative effectiveness of an intermittent 5-ASA regimen and a continuous 5-ASA regimen for the maintenance treatment of patients with ulcerative colitis in remission. Fifty patients with ulcerative colitis in remission for a minimum period of 1 month participated in the study. Twenty five patients received an intermittent treatment with 5-ASA tablets (2.4 g for the first week of each month) and 25 received a continuous treatment with tablets (1.6 g each day). Patients were assessed clinically every two months and endoscopically every 6 months. Our results show that the two treatments were equally effective. The relapse-free rates at 12 months were 71% in patients receiving the intermittent treatment and 66% in patients given the continuous treatment. This difference is not statically significant. Further studies are needed to assess whether the intermittent regimen can be an alternative to life-long treatment in patients who have maintained remission for a long period of time.

Administration, Oral

5-Aminosalicylic acid in pregnancy: clinical report.

Ulcerative colitis (UC) is a disease condition which typically affects young people; pregnancy is therefore frequent in women with this disease. 5-aminosalicylic acid (5-ASA) is known to be efficacious in maintaining remission of UC, but its safety in pregnancy has not yet been established. In the present study, the safety of 5-ASA was assessed in 16 women with UC (mean age: 31 years, range 25-35) who had a total of 19 pregnancies over the period from 1988 to 1992. All the patients were in clinical remission of UC at the beginning of pregnancy and were receiving a regular maintenance therapy with 5-ASA (ASACOL tablets, 1.2 g/day). During pregnancy, 4 women had a clinical relapse requiring treatment with higher doses of 5-ASA and, in some cases, with steroids. Our observations confirm that the treatment with 5-ASA does not affect the course of pregnancy nor does it damage the fetus, but it can protect from recurrences of UC.

Adult

Testicular function in patients with differentiated thyroid carcinoma treated with radioiodine.

UNLABELLED: The aim of the present study was to assess whether 131I therapy for differentiated thyroid carcinoma (DTC) can affect endocrine testicular function. METHODS: Serum follicle-stimulating hormone (FSH) and testosterone (T) concentrations were measured in 103 patients periodically submitted for radioiodine therapy for residual or metastatic disease. Mean follow-up was 93.7 +/- 54 mo (range 10-243 mo). RESULTS: Mean FSH values in 131I-treated patients tested after their last treatment were 15.3 +/- 9.9 mU/ml, significantly higher than those of 19 untreated patients (6.5 +/- 3.1 mU/ml). Considering the mean +3 s.d. FSH of untreated subjects as the upper limit of normal range, 36.8% of the patients had an abnormal increase in serum FSH. Longitudinal analysis performed in 21 patients showed that the behavior of FSH in response to 131I therapy was not universal. Six patients had no change or a slight increase in serum FSH after 131I administration; eleven patients had a transient increase above normal values 6-12 mo after 131I treatment, with return to normal levels in subsequent months. The administration of a second dose was followed by a similar increase in FSH levels. Finally, four patients, followed for a long period of time and treated with several 131I doses, showed a progressive increase in serum FSH, which eventually became permanent. Semen analysis, performed in a small subgroup of patients, showed a consistent reduction in the number of normokinetic sperm. No change was found in serum T levels between treated and untreated patients. CONCLUSIONS: Our results indicate that 131I therapy for thyroid carcinoma is associated with transient impairment of testicular germinal cell function. The damage may become permanent for high-radiation activities delivered year after year and might pose a significant risk of infertility.

Adenocarcinoma, Follicular

Multiple endocrine neoplasia type 2A and cutaneous lichen amyloidosis: description of a new family.

Multiple endocrine neoplasia (MEN) 2A associated to cutaneous lichen amyloidosis is a variant of MEN 2A recently reported in few families. We describe an additional family with this syndrome. The skin lesion is a pruritic one, located over the upper back showing, at biopsy, cutaneous amyloid. The propositus of our family was a 35-year-old woman already treated with total thyroidectomy for medullary thyroid cancer and with bilateral adrenalectomy for pheochromocytoma. The patient referred that the skin lesion was present since childhood and increased with time. Skin biopsy showed negative staining for amyloid, for calcitonin and neuron-specific enolase. The paraspinal muscles corresponding to the area of affected skin showed slight neurogenic abnormalities. Ten other members of her family were affected by MEN 2A, three of whom (all females) had the same cutaneous alteration.

Adrenal Gland Neoplasms

Salmonella brandenburg: a novel cause of acute suppurative thyroiditis.

A patient with suppurative thyroiditis due to infection with Salmonella brandenburg is reported. Localization of the infection occurred to a pre-existing thyroid nodule after Salmonella bacteremia. S. brandenburg was isolated in pure culture from the fluid obtained by needle aspiration of the suppurated thyroid nodule. Surgical drainage followed by subtotal thyroidectomy was required to cure the disease. No evidence of pyriform sinus fistula was found. Suppurative thyroiditis due to Salmonella ubiquitous serotypes is an extremely rare condition, and infection to the thyroid produced by S. brandenburg is reported now for the first time. Indeed, the isolation rate of S. brandenburg from all human sources is low, and this microorganism is an uncommon agent of bacteremia.

Adult

Acute intragastric application of capsaicin inhibits 2-deoxy-D-glucose--but not histamine-induced gastric acid secretion in the dog.

In this study the influence of acute exposure of gastric mucosa to the sensory neurotoxin capsaicin on basal gastric acid secretion and on secretion induced by 2-deoxy-D-glucose or histamine in conscious dogs with gastric fistulae has been investigated. Under basal conditions intragastric capsaicin (160 microM, 50 ml of volume) did not induce any significant change in acid secretion and in plasma levels of gastrin. Total acid output induced by 2-deoxy-D-glucose (75 mg/kg i.v.) was significantly decreased by intragastric application of capsaicin, while plasma gastrin concentrations were unaffected. A direct stimulant of the parietal cells, such as histamine (64 micrograms/kg s.c.) increased gastric acid secretion which was not sensitive to capsaicin pretreatment. These findings indicate the involvement of capsaicin-sensitive fibers in the control of vagally-induced gastric acid secretion in the dog.

Animals

Detection of thyroglobulin in fine needle aspirates of nonthyroidal neck masses: a clue to the diagnosis of metastatic differentiated thyroid cancer.

We studied the feasibility of employing the measurement of thyroglobulin (Tg) in the washout of the needle used to perform the fine needle aspiration cytology (FNA-Tg) for the differential diagnosis of nonthyroidal neck masses of unknown etiology. We studied 35 patients presenting for 1 or more neck lumps outside the thyroid gland. A previous history of treated differentiated thyroid cancer (DTC) was given by 23 patients and of nonthyroidal malignancy by 3 patients. FNA-Tg was measured in the Tg-free serum used to wash out the needle employed for the cytology. Finally, all patients were treated by surgery. FNA-Tg was always detectable in 14 patients with thyroid cancer metastases demonstrated by histology, with a mean (+/- SD) of 27,087 +/- 37,622 ng/FNA (P less than 0.002) compared to patients without thyroid cancer metastases (mean +/- SD, 12.1 +/- 4.8 ng/FNA in 7 cases; undetectable in 14 cases). Assuming 21.7 ng/FNA (the mean +/- 2 SD of the negative patients) as the cut-off value, all patients with metastases from DTC were detected by FNA-Tg. FNA-Tg had better negative predictive value than cytology, since this last technique gave 10 inconclusive results, comprising 2 false negative results in patients with metastases from DTC. Our results indicate that elevated concentrations of FNA-Tg in nonthyroidal neck nodes strongly suggest the diagnosis of metastases from DTC.

Adolescent

Percutaneous intranodular ethanol injection for treatment of autonomously functioning thyroid nodules.

BACKGROUND: The aim of the study is the assessment of percutaneous intranodular ethanol injection (PNEI) as an alternative therapeutic procedure to classic surgery and radioiodine administration in autonomously functioning thyroid nodule treatment. METHODS: Thirty-seven patients with hot nodules (18 pretoxic and 19 toxic) have been treated by means of PNEI under ultrasonographic guide. Ninety-five percent ethanol in a mean dose of 25 ml has been used. RESULTS: Nearly 80% of the patients showed normalization of thyroid-stimulating hormone levels and a complete recovery of extranodular tissue at scintiscan. All nodules decreased strikingly in size, many becoming undetectable. Mild and transient side effects were seen in 9% of the patients. CONCLUSIONS: PNEI seems to be a feasible procedure on outpatients. It is safe when performed by a well-trained staff using ultrasonographic control. It may be carried out at any age and in patients at risk for surgery. PNEI can be considered a useful alternative to surgery and radioiodine administration in all autonomously functioning thyroid nodules and particularly in pretoxic nodules.

Administration, Cutaneous

Medullary thyroid cancer. An immunohistochemical and humoral study using six separate antigens.

The authors investigated the humoral and tissue expression of six antigens associated with medullary thyroid cancer (MTC): calcitonin (CT), calcitonin gene-related peptide (CGRP), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), somatostatin (SRIF), and thyroglobulin (TG). The antigens were studied in the neoplastic C cells using immunohistochemistry with specific antisera and in the plasma using specific radioimmunoassay. Eighteen patients (8 male and 10 female patients, aged 12-72 years) were studied. Mean follow-up was 70.7 months (range, 2-179 months). Nine patients (50%) died of their disease after a mean follow-up of 47.2 months (range, 2-116 months). By immunostaining, primary tumors expressed CT and CEA in all cases and NSE was positive in 90%, CGRP in 66%, SRIF in 63%, and TG in 58%. Metastatic tissues were positive in all cases of CT staining, 92.8% of CEA, 71.4% of NSE, 73.3% of CGRP, 38.5% of SRIF, and only 13.3% of TG staining. In positive cases the percentage of positive cells and the degree of staining were variable among the different antigens. The expression of an antigen in the neoplastic cells was associated with the hypersecretion of the corresponding antigen in the circulation in the case of CT and CEA. The levels of these antigens were elevated in all patients with metastases and could accurately predict the appearance of new metastases or indicate the effective treatment of previous metastases by surgery. In the case of NSE, CGRP, and SRIF, few patients had increased plasma concentrations of the antigens and these usually occurred during very advanced phases of the disease. Detectable levels of serum TG were never observed. When the outcome of the disease was compared with the expression of CT, CEA, NSE, CGRP, and TG, no correlation could be found. On the contrary, SRIF expression in the primary tumor could differentiate two groups of patients with different survival rates. SRIF-positive patients had survival rates of 100% and 50% at five and seven years, respectively, whereas SRIF-negative patients had survival rates of 40% at five years and 25% at seven years.

Adolescent