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Biomedical subjects

A Costa

Publications and source records attributed to A Costa.

At least 379 records · Page 21Linked to original sources
PubMed1986

Development of thyroid function between VI-IX month of fetal life in humans.

Well-preserved thyroid glands from 28 fetuses 22-34 weeks of gestational age and from 4 term newborns who survived at most 12 days were examined to study thyroid development in late intrauterine life. Total iodine thyroglobulin (Tg), T4, T3 and rT3 were assayed before and after hydrolysis with pronase. In the same maternity unit the cord-serum of 25 healthy term newborns was also assayed and the urine iodine on the day of delivery was tested in 52 newborns and their mothers. Results are expressed as mean values +/- SD. The thyroid gland weight ratio to body weight for the preterms was 0.063 +/- 0.024; thyroid Tg content 5.9 +/- 4.0 mg/g; total thyroid iodine 41.7 +/- 35.1 micrograms/g; Tg iodination 0.72 +/- 0.37%; hormone quota of Tg iodine 39.9 +/- 12.4. Molar ratios were: T4/Tg 3.3 +/- 1.6, T3/Tg 0.25 +/- 0.14, rT3/Tg 0.072 +/- 0.059. Considerable differences in thyroid iodine content and Tg iodination were observed although the availability of iodine was presumably the same. The high Tg iodination reflects the enhanced uptake of the fetal thyroid. The quantity of iodine involved in hormonogenesis varied greatly among fetuses of the same gestational age, this being in the third term as active as in fully mature thyroids. Hormonogenesis seemed preferentially directed to production of T4 and rT3, which, in the latter case, is higher peripherically. Four preterms with a particularly low level of hormonogenesis were not seen to have deficient levels of thyroid iodine or Tg iodination and the most compromised step was the iodine utilization in the production of hormones.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital Hypothyroidism↗
PubMed1986

Immunological features of endemic goiter.

Some immune aspects of simple endemic goiter have been studied through a comparison of IgG, IgA, IgM, kappa and lambda chains, and C3 and C4 in the peripheral blood of 59 patients operated on for goiter and the peripheral blood of 49 normal controls. The median IgM was lower in the goiter blood. The incidence of thyroglobulin (Tg) and microsomal (Mi) antibodies (Abs) was 20.3% in goiter blood and that of nonthyroid autoAbs was 37%. Active and total rosetted blood lymphocytes were counted and OKT3, OKT4, OKT8, Leu 1, Leu3a, Leu2b, T DR+, and NK cell populations were classified. Helper T cells were occasionally decreased when goiter was associated with lymphocytic thyroiditis. The NK percentage was sometimes higher in goiter blood, whereas the T DR+ percentage was not significantly different in the two groups. Lymphocyte infiltration (LI) was noted in 32% of goiters (about 5% with a diffuse and nodular pattern). A prevalence of helper/inducer cells was observed among the infiltrating T cells. HLA-DR antigen (Ag) positive epithelial cells were seen, not only in LI areas. Granular deposits of IgG, IgA, IgM, and C3 on the follicular basal membrane were stained in 6.7% of goiters Patterns histologically and immunologically similar to those in Hashimoto's thyroiditis may therefore be observed in long-standing simple endemic goiter, suggesting that an autoimmune mechanism may be involved in its pathogenesis.

Autoantibodies↗
PubMed1986

Analysis of amniotic fluid proteins by isoelectrofocusing (IEF) in pregnancies complicated by polyhydramnios and Rh-sensitization.

Among the most recent methods for investigation of proteins in biological fluids SDS polyacrilamide-gel-electrophoresis (SDS-PAGE) and isoelectrofocusing (IEF) have recently been introduced into laboratory practice. The present investigation was performed on 14 samples of amniotic fluid obtained during the third trimester in pregnancies complicated by Rh-sensitization and polyhydramnios in which protein concentration was higher than in normal pregnancies. The obtained results suggest that IEF analysis seems to have a selective advantage in allowing the separation of bands which cannot easily be recognized with SDS electrophoresis. These bands detected by IEF and present in amniotic fluid during late pregnancy seem to be related to some molecular weight lipoprotein fractions and we suggest that they might be used as a possible marker for monitoring fetal lung maturation. In conclusion we think that it would be of great interest to evaluate the usefulness of IEF analysis in examining amniotic fluid obtained during pregnancies complicated by polyhydramnios and Rh-sensitization.

Amniotic Fluid↗
PubMed1986

[Carcinoma cuniculatum of the hand].

We've made a brief account of Carcinoma Cuniculatum and after reviewing the references, we found four cases which didn't appear on the foot as usual. We've reported a 68-year-old man, with a lesion on the back of his left hand; it had been present six years and had recurred after a surgical excision. On the clinical point of view, the lesion is a roughly oval 7 X 5 cm., plaque formed by the junction of small violaceous nodules. The surface is keratotic and it presents multiple sinuses from where a white, greasy material oozed out. Concerning the pathological findings we can observe that the papillomatous surface squamous epithelium penetrated into the underlying tissue. The epithelium contained sinuses which were filled with keratin. Occasionally the epithelium showed individual cell keratinization. The squamous epithelium was well differentiated and a feature seen was intra-cellular oedema, with sheets of uniform, pale, staining epithelium. Mitotic activity was low and confined to the basal layers. The tumour was accompanied by a fibrous stroma which was somewhere heavily infiltrated by chronic inflammatory cells. The treatment consisted of a wide excision and graft. As to the aetiology of the tumour the different authors suggest several possibilities, since the enduring trauma, chronic inflammation, burn scars, radiation, arsenic ingestion until the viral aetiology. McKee and Wilkinson suggest that it's a multifactorial process, playing the wart virus the main part in the breaking out of the tumour.

Aged↗
PubMed1986

Cell kinetics of gliomas by serial stereotactic biopsy.

The potential proliferative activity of glial tumors has been investigate by serial stereotactic biopsies and by "in vitro" 3H-thymidine incorporation procedure (labeling index, LI). The methodology of this combined approach and the preliminary results in 33 patients are reported. Cell kinetic data have been matched with the histological classification (W.H.O.).

Adolescent↗
PubMed1986

Morphological and clinical significance of cell kinetics in non-Hodgkin's lymphomas.

The relation between the proliferative activity and morphologic features according to Rappaport and Kiel classifications and the Working Formulation (WF) was analyzed in a series of 123 adult patients with non-Hodgkin lymphomas. Cell kinetics was determined as in vitro 3H-thymidine labelling index (LI). A significant association was observed between low LI and follicular histology or low grade of the WF, as well as between high LI and high-grade of malignancy of the Kiel and WF. The analysis of the clinical relevance of cell kinetics on objective response to treatment showed a higher frequency (91%) of complete remission in the tumors with low proliferative activity versus tumors with high proliferative activity (48%) (p = 0.00003). Moreover, cell kinetics proved to be and important indicator of 6-year survival on the whole population of patients (66% for slowly vs 18% for fast-proliferating tumors; p less than 10(-9)) and a further discriminant within diffuse histology (68% vs 9%; p less than 0.0001), low-grade malignancy according to the Kiel (64% vs 15%; p less than 10(-8)) and low (64% vs 28%; p less than 0.005) and intermediate grades of the WF (68% vs 9%; p less than 0.0001).

Adolescent↗
PubMed1986

Cell kinetics to monitor radioresponsivity in human epidermoid carcinoma.

The clinical relevance of proliferative activity as an indicator of radioresponsivity was investigated in advanced epidermoid carcinomas of the oral cavity. Proliferative activity, determined in vitro as 3H-thymidine labeling index, was assessed before starting radiotherapy and after 10 Gy. In a series of 35 patients, pretreatment proliferative activity was not indicative of response to radiotherapy. Conversely, in the same series of patients, an association was observed between an early variation of proliferative activity induced by 10 Gy and the response to the full course of radiotherapy. The effect on proliferative activity was not related to tumor volume reduction but to long-term clinical response. An inhibition of more or less than 70% was significantly correlated with long-term clinical outcome at 36 months in terms of the probability of local recurrence (29% vs 90%; p = 0.002) and overall survival (55% vs 16%; p = 0.006) at 36 months.

Carcinoma, Squamous Cell↗
PubMed1986

Kinetic pattern of human urinary transitional cell carcinoma.

The potential proliferative activity, expressed as labelling index, has been studied in 24 cases of bladder transitional cell carcinomas. The data showed a wide range of values, varying between 0.4 and 36%. The average proliferative activity was 3.2%. An analysis of the connection between the labelling index and the histological grading has also brought out the existence of a gradient of proliferative activity; average values of 1.6-2.53% and 3.49%, respectively, were found for grades I-II and grade III.

Adult↗
PubMed1986

High homology of membrane proteins electrophoretic pattern in Bacteroides fragilis as confirmed by various solubilizing methods.

Membrane proteins from 25 strains of B. fragilis isolated in different laboratories in Northern Italy were examined by SDS-PAGE and isoelectrofocusing. The electrophoretic patterns of inner and outer membrane after Sarkosyl and SDS solubilization of all the isolates were consistently similar to that of the reference strain. The protein profiles of the different species belonging to the B. fragilis group are clearly distinguishable with negligible similarities. Our data clearly show that this approach is extremely helpful and reliable in providing additional verification of the identity of strains recognized by conventional tests. In this connection PAGIF analysis of triton solubilized isolated envelopes reduces technical time and difficulties, thus improving analytical accuracy.

Bacteroides Infections↗
PubMed1985

Validation of a mathematical procedure for computer analysis of flow cytometric DNA data in human tumors.

The determination of tritiated thymidine labeling index and the percentage of cells with S phase DNA content was performed on cell suspensions obtained from 69 patients with non-Hodgkin's lymphoma. The distributions of cells in the cell cycle by computer analysis of flow cytometric data were obtained by two mathematical procedures: the widely adopted Fried model and a new one proposed by Bruni et al. A significant agreement was observed by checking the Spearman index (rs) between the percentages of cells in the different cell cycle phases (G0/1, rs = 0.76; S, rs = 0.60; and G2 + M, rs = 0.43; p less than 0.001) determined by the two procedures. Similarly, a good correlation was observed between the labeling index (LI) and the S phase values obtained by the Fried (rs = 0.45, p less than 0.001) and Bruni (rs = 0.69, p less than 0.001) models, but with a higher agreement for the latter one. The S phase by the Bruni model was also superior in predicting LI: in fact, by employing the S cutoff value of 12%, a better agreement between low LI and low S phase or high LI and high S phase was observed with the Bruni procedure (90%) than with the Fried model (72%). Finally, the analysis of the prognostic significance of the different kinetic variables confirmed the prognostic relevance of LI at any time; the S phase percentage as determined by Bruni et al. was discriminant of survival only at shorter times, and no prognostic significance could be ascribed to S phase according to the Fried procedure.

Adult↗
PubMed1985

Cell kinetics of neuroepithelial tumors in serial stereotactic biopsies. A new combined approach.

33 consecutive patients with brain glial tumors underwent serial stereotactic biopsies and (3H)-thymidine in vitro investigation. The labeling index has been determined in each case and matched with the WHO histological classification. The feasibility and the accuracy of cell kinetics study applied to stereotactic biopsies are discussed in view of future application for prognostic purposes. Particular attention is given to the description of the method.

Adolescent↗
PubMed1984

Thiocyanates and iodine in endemic goiter in Italy.

Urinary iodine (I) and serum and urinary thiocyanates (SCN-) were determined in sample groups from 12 areas of endemic goiter in Italy. The mean urinary I level of 637 subjects with thyroid 0 was 67 +/- 31 (mean +/- SD) microgram/liter, that of 648 with goiter 54 +/- 29 micrograms/liter. Mean serum and urinary SCN- were 2.44 +/- 1.36 mg/liter and 2.58 +/- 1.36 mg/liter in 887 and 1531 subjects, respectively. The thiocyanates data enabled a distinction to be drawn between two groups (populations). Population I included 73% of the adults and 92% of the school-children (6-16 yr). Its thiocyanate values were logarithmically spread around means of 1.24 +/- 0.6 mg/liter (serum) and 1.24 +/- 0.57 mg/liter (urine), whereas those of population II were widely dispersed around means of 6.1 +/- 3.0 mg/liter and 8.08 +/- 5.5 mg/liter respectively. The boundary between the two populations was set at 3 mg/liter urine SCN-. This distinction was substantiated by the fact that 90% of those in population II smoked 10 or more cigarettes a day, whereas population I comprised occasionally smokers only. It is believed that only the values in population I can be regarded as representative of thiocyanates either endogenous or due to dietary dietary intake: these values never differed more than 60% regardless of the areas, seasons, or dietary habits. As urinary SCN- levels rose, there was also an increase in urinary iodine excretion within certain limits. This, however, did not interfere with thyroid secretion. The urinary I/SCN- ratio was lower in subjects with goiter. This was because their iodine levels were lower, whereas SCN- values were much the same in subjects with and without goiter. We have found no correlation between thiocyanate itself and goiter.

Adolescent↗
PubMed1984

Short-term variation in labeling index as a predictor of radiotherapy response in human oral cavity carcinoma.

In vitro determination of [3H]thymidine labeling index (LI) was carried out on squamous cell carcinomas of the oral cavity from 52 patients before and during radiotherapy. Pretreatment LI values ranged from 0.01% to 50%. After administration of the first 10 Gy in five consecutive daily fractions, a decrease in LI was observed in 39 cases and an enhancement in 13 cases, with an overall median 70% decrease in the initial value. The type of variation induced by radiotherapy was not related to pretreatment LI except for tumors with a very low proliferative activity (LI less than or equal to 1.9%), which all showed a marked increase in LI. Pretreatment LI was not indicative of short- or long-term response to radiotherapy, whereas the variation induced on LI after 10 Gy was related to the clinical outcome. A variation in LI of more or less than 70% was not significantly associated (p = 0.077) with clinical objective response (respectively, 85 and 53%). However, all 8 patients who reached a complete regression, notwithstanding an enhancement or a slight decrease in LI, had a local recurrence within 19 months. Conversely, the probability of disease-free survival was 82% for the 11 patients whose tumors had a significant decrease in LI (greater than or equal to 70%) after the first 10 Gy.

Aged↗