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Biomedical subjects

M Tommasi

Publications and source records attributed to M Tommasi.

At least 163 records · Page 9Linked to original sources
PubMedDate not supplied

Phenotypic analysis of human peripheral blood lymphocytes by automatic sampling flow cytometry after stimulation with mitogens or allogeneic cells.

Human peripheral blood lymphocyte (PBL) phenotypes have been analyzed before and after stimulation with phytohemagglutinin (PHA), concanavalin A (ConA) and pokeweed mitogen (PWM) for 3 days and in mixed lymphocyte culture (MLC) for 7 days. PBL labeled with each of 10 fluorescent monoclonal antibodies were automatically sampled for flow cytometry from 96-well microtiter plates using a microsample delivery system. The reference phenotypic ranges were determined in fresh cells and control cultures. PHA was mostly mitogenic for T PBL bearing the CD3, CD5, CD7, CD8 and CD25 differentiation clusters, and a low density of CD1 and CD4 had a small effect on human natural killer cells (HNK) and also did not stimulate B (CD19) and HLA-DR+ PBL. There was an incomplete phenotypic overlapping between PHA- and ConA-stimulated cultures, ConA being more mitogenic for CD4 and less mitogenic for CD8 PBL. The mitogenic effect of PWM was evident on CD3, CD5, CD7, CD4, CD25 and CD8, but not on HNK, HLA-DR and CD19 B PBL, which presumably had already differentiated into antibody-secreting cells. After MLC stimulation all T, B and HNK PBL subsets tested were increased, but the cells bearing CD1, CD4, CD5, CD7, CD25, HNK, CD19 and HLA-DR had the greatest proliferation with respect to the unmixed control PBL. The present approach to the phenotyping of PBL subsets could offer more complete and accurate data for monitoring and follow-up of patients in transplantation and immunopathology hospital wards.

Antibodies, Monoclonal↗
PubMedDate not supplied

Structural analysis of the CD69 early activation antigen by two monoclonal antibodies directed to different epitopes.

The biochemical structure of CD69 early activation antigen has been characterized by means of two newly isolated mAb, namely C1.18 and E16.5. Upon analysis by SDS-PAGE, C1.18-reactive molecules immunoprecipitated from 125I-surface labeled PMA activated PBL consisted of a 32 + 32 kD dimer, a 32 + 26 kD dimer, a 26 + 26 kD dimer and a 21 + 21 kD dimer. E16.5-reactive molecules consisted of a 26 + 26 kD dimer and a 21 + 21 kD dimer. Cross absorption experiments showed that E16.5 mAb reacts with an epitope of the CD69 molecule distinct from the one recognized by C1.18 mAb and present only on a subpopulation of the CD69 molecular pool. The patterns of migration of C1.18- and E16.5-reactive molecules in two-dimensional gel-electrophoresis, under reducing conditions before and after treatment with Endoglycosidase F enzyme suggest that the two mAb recognize the same glycoprotein structure, but in two distinct glycosylation forms, both expressed on the cell surface membrane. Finally, p32, p26 and p21 of CD69 complex obtained from three distinct normal donors did not show appreciable structural polymorphism, by two-dimensional peptide mapping, not only among single subunits within the same individual, but also among homologous subunits in distinct individuals. Further, it was found that CD69 complex is expressed at the cell surface of resting PBL, although at a very reduced level in comparison to PMA activated cells. C1.18 and E16.5 mAb induced comparable cell proliferation and IL-2 production in PBL in the presence of PMA. C1.18 mAb increased intracellular free calcium concn in PMA activated PBL after cross-linking with goat anti mouse Ig, while the effect induced by E16.5 mAb after cross-linking was consistently lower. Finally, it was found that Sepharose-linked C1.18 mAb, in the presence of rIL-2 or PMA, did not induce TNF release from 6 NK cell clones.

Antibodies, Monoclonal↗
PubMedDate not supplied

[Severe traumatic coma from diffuse brain lesions (neuropathological aspects) (author's transl)].

From a review of recent literature, and pathological study of more than 100 personal cases, the authors describe the most interesting of these "diffuse" lesions; they only recall the most common types of lesions (contusions, vascular lesions, edema and its consequences - especially on brain stem); but a more detailed description is given of less known lesions of corpus callosum, brain stem and white matter, which have a more complex pathogeny (direct physical injury, anoxia-ischaemia, edema), and which they consider to be factors which worsen or protract the coma. "Biochemical" lesions (basic myelinic protein, liberated "false" neurotransmitters) are also discussed.

Brain↗
PubMedDate not supplied

The role of a new monoclonal antibody assay in the detection of recurrent breast cancer.

The immunoradiometric assay "CA 15-3", recently developed to measure a breast tumor-associated antigen, gave a mean serum value of 13.8 U/ml (S.D. 6.2) for this antigen in 156 non-cancer controls (36 biopsies for a benign breast lesion and 120 healthy controls). Setting a cut-off value of 30 U/ml (specificity 99.3%), only 3 out of 58 primary breast cancer cases were positive. In metastatic breast cancer, 11 out of 33 cases with limited recurrence (33.3%) and 36 out of 56 cases with extensive recurrence (64.3%) gave abnormal values in this assay, above the cut-off point, with an overall sensitivity of 52.8%; the difference between the sensitivity values in the two groups of recurrent cases was statistically significant (P less than 0.01). According to the findings of the present study, CA 15-3 has no role in the detection of primary breast cancer, but its usefulness in disease monitoring can be hypothesized, as circulating levels of the antigen seem to be dependent on the tumor mass.

Adult↗
PubMedDate not supplied

Creatine kinase isoenzyme BB: a lung cancer associated marker.

We investigated the diagnostic role of creatine kinase isoenzyme BB (CK-BB) in lung cancer. CK-BB was assayed using a radioimmunological system by saturation with Mallinchrodt double antibody 125I labelled (RIA Quant-CPK-BB). Sensitivity was 97% and specificity 90% in 44 cancers (T2-T3), in 36 non-cancers (chronic bronchitis) and in 48 healthy controls. Mean serum CK-BB values for patients with chronic bronchitis (2.64 +/- 1.1 ng/ml) were virtually the same as in normal subjects. Patients with lung cancer had markedly higher serum CK-BB values (9.17 +/- 2.6 ng/ml) than either the control group (healthy subjects) or the chronic bronchitis patients (p less than 0.01). These results lead us to suggest that CK-BB serum determination might prove useful in screening pulmonary disorders. However, further studies are essential to establish: 1) the relationship between serum levels of the isoenzyme and the histology and stage of the neoplastic disease; 2) the relation between CK-BB and the aggressive potential of the neoplastic clone.

Adenocarcinoma↗
PubMedDate not supplied

Intraoperative fall in plasma levels of intact parathyroid hormone in patients undergoing parathyroid adenomectomy.

Intraoperative measurement of intact parathyroid hormone (PTH) can be used to evaluate the success of parathyroid surgery in primary hyperparathyroidism associated with parathyroid adenoma. To evaluate this approach we used a modified immunoradiometric assay (IRMA) to study the kinetic patterns of circulating PTH disappearance in 13 patients undergoing adenomectomy for single adenoma. The rapid and the standard assay for PTH measurement in plasma were used and compared. The two methods showed a highly significant correlation (r = 0.995; p < 0.0001). We reported a decrease in PTH to 18.2 +/- 2.30 (mean +/- SEM) from baseline values at 15 minutes after successful parathyroid adenomectomy in the 13 patients. The biphasic pattern of serum PTH clearance was calculated in 8 of the studied patients with a fast phase showing a half-life (T1/2) of 3.99 (SEM 0.464) minutes and a slow phase with a T1/2 of 91.0 (SEM 33.6) minutes. Half the amount of the basal values was reached between 4 and 9 minutes. Our study concludes that the modified IRMA for intraoperative measurement is feasible, reliable and sufficiently precise for low hormone values. Since it may yield information on the half-life of PTH in the circulation, it may play a role in the surgical guidance for total exeresis of hyperfunctioning tissue.

Adenoma↗
PubMedDate not supplied

Serum biochemical markers of bone turnover in healthy infants and children.

Serum osteocalcin (OC), bone alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), carboxyterminal telopeptide of type I collagen (ICTP), parathyroid hormone (PTH) and 1,25 dihydroxyvitamin D [1,25(OH)2D] were measured in 241 normal infants and children (134 males and 107 females aged 1.9 months-14 years, 1.8 months-12 years, respectively). Regarding the analysis of data for children above 2 yrs, we chose data with the following normalization: data/body surface x standard body surface, to eliminate biological variations not exclusively related to chronological age. The increase in serum OC occurred at the expected age of growth spurts in both sexes: in the first year of life OC values (mean +/- SD) were 82.6 +/- 34.3 and 60.2 +/- 32.9 OC ng/ml in males and females, respectively; during puberty, peak values occurred at the age of 10-12 yrs in girls (76.6 +/- 25.8) and at the age of 12-14 yrs in boys (113 +/- 48.3). Furthermore, significant positive correlations with age were found for males from 2 to 14 yrs (p < 0.00001) and for females from 2 to 12 yrs (p < 0.001). Elevated levels of BAP occurred in the first year, 70.4 +/- 28.2 and 71.8 +/- 28.5, and in the second year, 69.4 +/- 26.7 and 67.4 +/- 33.8 ng/ml, for males and females, respectively. For children older than 2 yrs, a positive correlation with age (p < 0.01) was found for females only, with a peak value of 67.2 +/- 13.9 at the age of 10-12 yrs. For ages 2-14 yrs the reference values (mean +/- 2SD) were 15.5 - 90.3 and 17.2 - 95.2 ng/ml for males and females, respectively. The highest PICP levels (1354 +/- 680 ng/ml in males and 1041 +/- 766 in females) were observed in infants less than 1 year of age, decreasing by about 60% at the age of 2. There was no significant change in serum PICP for children older than 2 yrs with values covering a range (mean +/- 2SD) of 52 - 544 and 18 - 546 ng/ml in males and females, respectively. Similarly, the highest ICTP values were seen in infants younger than 1 year (29.7 +/- 11.7 and 29.5 +/- 20.1 ng/ml in males and females, respectively). In the ages from 2 to 14 yrs there did not seem to be any systematic age-correlated changes, with values covering a range (mean +/- 2SD) of 6.06 - 24.5 in boys and 6.84 - 22.9 ng/ml in girls. Serum PTH concentrations (mean +/- SD) in infancy were 27.2 +/- 19.3 pg/ml for males and 25.8 +/- 10.8 for females. Normal ranges (mean +/- 2SD) in the older group were 5.77 - 53.1 and 6.71 - 57.3 pg/ml for males and females, respectively. Serum 1,25(OH)2D presented values of 47.3 +/- 28.1 and 38.7 +/- 18.2 pg/ml under 2 yrs for males and females, respectively. The ranges (mean +/- 2SD) in children above 2 yrs were 9.5 - 101 pg/ml in boys and 10.9 - 88.4 in girls. The results of this study contribute to the establishment of reference values in normal children for these biochemical assays; these reference values are needed when the above biological markers will be applied in the monitoring of metabolic bone diseases.

Alkaline Phosphatase↗
PubMedDate not supplied

A controversial problem: is there a relationship between parathyroid hormone level and parathyroid size in primary hyperparathyroidism?

The current study was undertaken with the aim of studying the relationship between parathyroid hormone and hyperfunctioning parathyroids by a sophisticated method of analysis. Our clinical study included 25 patients undergoing surgery for primary hyperparathyroidism. The measurement of basal circulating intact PTH (pg/ml) and the volume (mm3) of the removed gland(s) were recorded. It was essential for the distribution of the sample values to be normal before Pearson's correlation and regression analysis were performed. The Kolmogorov-Smirnov test showed sufficient sample data agreement (p > 20%) with normal distribution after their transformation into natural logarithm (ln) and so statistical analysis was performed utilizing ln transformed data. The regression line between basal ln of iPTH levels (x) and ln of tumor volume (y) was highly significant (y = 2.3828 + 1.0424 x, r = .72504, p < .0001). In our opinion, the above is a correct statistical procedure with reliable results.

Adult↗
PubMedDate not supplied

[Inflammatory granulomas in the pathology of the nervous system. General remarks].

The "gliogenic" participation in the edification of granulomas may produce peculiar morphological features especially in the central nervous system, and perhaps more than elsewhere, pseudotumoral features. Moreover, the concept of "granuloma" is perhaps not as well defined as in the other tissues. There are also some still unsolved problems concerning the histogenesis of the cells of the "granuloma". Some examples taken among the different etiologies illustrate these notions.

Granuloma↗
PubMedDate not supplied

[Extemporaneous histopathological examination in neurosurgery. Report on 500 cases].

The authors review 500 extemporaneous histopathological examinations done in a neurosurgical unit over a 16-month period. The following four questions are asked by the neurosurgeon: is there a tumor? is it a primary or secondary one? what variety is it? what is its degree of malignancy? The percentage of errors was respectively: 2 per cent, 2.2 per cent, 8.8 per cent and 7.4 per cent, or roughly, a percentage two times lower than in a series from the same laboratory done before the use of the low-temperature microtome. It especially seems that the tumoral variety is often determined accurately in meningiomas, neurinomas, medulloblastomas and craniopharyngiomas. In gliomas the variety is often more difficult to accurately affirm, and especially the "grade" of malignancy. The authors analyse the problems raised by the different types of tumors.

Brain Neoplasms↗
PubMedDate not supplied

[Amyloid neuropathy. Ultrastructural study of 2 new cases].

Two familial and sporadic cases of amyloid neuropathy are reported. Nerve biopsies ultrastructural studies permit to involve endothelial and Schwann cells basement membranes into formation of amyloid. This classical notion was worth being recalled and specified. The purpose of amyloid formation is searched in a toxico-metabolic processus possibly in relation with observed demyelinating mechanism. The Schwann cell is at the cross of the cause and of its effect.

Adult↗