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Biomedical subjects

P Neve

Publications and source records attributed to P Neve.

At least 19 recordsLinked to original sources
PubMed1995

A case of pleomorphic T-cell lymphoma with a high content of reactive histiocytes presented with hypereosinophilia.

A case of peripheral T-cell lymphoma classified, according to the updated Kiel classification, as a large pleomorphic T-cell lymphoma with a high content of reactive histiocytes and blood hypereosinophilia is reported. Light microscopic examination revealed a diffuse effacement of the lymph node structure by large pleomorphic lymphoma cells mixed with eosinophils and many histiocytes, some of them presenting discrete features of hemophagocytosis. The neoplastic cells were CD3, CD5, CD8 and HLA-DR positive but failed to show CD30 antigen. DNA molecular analysis displayed simultaneous rearrangements of the genes coding for the delta chain of the T-cell receptor and for the Ig heavy chain. Increased serum levels of angiotensin converting enzyme and ferritin were found and probably induced by the reactive histiocytes. Immunoassays (ELISA) with antibodies directed against some cytokines and against the Tac peptide (sIL-2R) were performed. They demonstrated high serum levels of sIL-2R and a slight increase in GM-CSF, but neither IL-5 nor IL-3. The association of blood hypereosinophilia and histiocytic hyperplasia with a peripheral T-cell lymphoma is discussed.

Adult↗
PubMed1994

Thiobarbiturate and fructosamine assays: significance and interest of the borohydride blank.

The acute-phase reaction (APR) induces the production by the liver of short-lived glycoproteins. The carbohydrate moiety of these proteins is thought to interfere with the thiobarbiturate (TBA) and nitroblue tetrazolium colorimetric tests which are used for assaying non-enzymatic glycosylation (NEG) of serum proteins. The aim of the present study was to assess the effect of the APR on the specificity of the colorimetric tests in non-diabetic and diabetic subjects. A positive correlation was found between C-reactive protein (CRP), an APR glycoprotein, and non-specific TBA reactivity as determined after borohydride reduction (BH4-resistant TBA, BR-TBA), both in non-diabetics (r = 0.61; P < 0.01) and diabetics (r = 0.68; P < 0.01). The BH4-sensitive specific TBA (SP-TBA) was not influenced by glycoproteins, and its increase in diabetics was correlated with the nitroblue tetrazolium assay (r = 0.89; P < 0.01). An independent effect of diabetes and APR on non-specific TBA was also demonstrated, suggesting an effect of hyperglycaemia on both protein glycation and glycosylation. TBA with borohydride reduction is an attractive tool for the study of complex glycoproteins in diabetes.

Acute-Phase Reaction↗
PubMed1993

Impaired phagocyte responses to lipopolysaccharide in paroxysmal nocturnal hemoglobinuria.

Bone marrow-derived cells from patients suffering from paroxysmal nocturnal hemoglobinuria (PNH) show a defect in the expression of phosphatidylinositol-anchored membrane proteins, including the CD14 molecule. Blocking experiments with anti-CD14 monoclonal antibodies have shown that lipopolysaccharide (LPS)-induced tumor necrosis factor alpha production by monocytes depends on the interaction between CD14 and a complex formed by LPS and LPS-binding protein. We used a whole-blood model to examine the LPS-induced production of tumor necrosis factor alpha and interleukin-6 in PNH patients and healthy volunteers. At low endotoxin concentrations (1 ng/ml), PNH patients displayed a marked defect in the production of both cytokines, whereas at high LPS concentrations (100 ng/ml), cytokine production was similar to that in healthy volunteers. Using flow cytometry, we also studied the expression of the adhesion molecules Mac-1 (CD11b/CD18) and ICAM-1 (CD54) by monocytes and granulocytes after LPS stimulation. Compared with phagocytes from healthy volunteers, CD14-deficient cells showed poor Mac-1 and ICAM-1 upregulation when whole blood was stimulated with LPS (1 ng/ml), whereas their response to higher LPS doses (100 and 1,000 ng/ml) was essentially normal. The importance of the CD14 molecule in the activation of phagocytes by low LPS concentrations was confirmed by the inhibitory effect of an anti-CD14 antibody both in healthy volunteers and in PNH patients. Since these patients produce the soluble form of the CD14 molecule, these data suggest that soluble CD14 could play a role in phagocyte responses to LPS. We conclude that, in whole blood, phagocytes from PNH patients show impaired responsiveness to LPS and this phenomenon is most probably related to their defect in expression of membrane CD14.

Antigens, CD↗
PubMed1992

Bone blood flow and in vitro proliferation of bone marrow and trabecular bone osteoblast-like cells in ovariectomized rats.

Ovariectomy in the rat induces a rapid osteopenia associated with an elevated bone turnover. One hundred and twenty-day-old rats were ovariectomized (OVX) or sham-operated (n = 6-8 per group and per time period studied). 45Ca accretion rate and bone blood flow (microspheres trapping technique) in the femurs were determined at 28, 42, 84, and 119 days after ovariectomy. Both parameters were markedly increased by 84 days and subsided thereafter. At the 42nd day, when bone turnover was maximal, bone marrow and trabecular bone cultures were obtained from sham-operated and ovariectomized animals (n = 10/group). Proliferation rate of bone marrow cells and trabecular osteoblast-like cells estimated by fibroblast colony-forming units (FCFU) efficiency and cell counting was markedly increased in primary and secondary cultures in ovariectomy. These data fitted well with the enhanced number of osteoblasts observed in situ in the long bone metaphyses of estrogen-depleted animals. As estrogens were shown in the literature to inhibit proliferation of the red cell line and of other hemopoietic lines, it is possible that estrogens, through a general mechanism, inhibit hemopoietic and stromal lines and also the proliferation of bone marrow-derived trabecular bone cells.

Animals↗
PubMed1992

The number of fibroblastic colonies formed from bone marrow is decreased and the in vitro proliferation rate of trabecular bone cells increased in aged rats.

Four- and 21-month old female Sprague-Dawley rats were sacrificed and their tibiae and femurs isolated for histology and initiation of bone marrow and trabecular bone cultures. The bone loss observed in 21-month old rats was associated with a markedly decreased osteoblastic index. The percentages of mineralizing trabecular surfaces were only slightly decreased in aged rats, whereas the percentages of mineralizing endocortical surfaces were strikingly decreased. Diaphyseal femoral marrows from 21-month old rats were less cellular than those from four-month old rats, and developed in culture fewer fibroblast colony forming units (FCFU) and fewer adherent cells with phenotypic characteristics of osteoblast-like cells. Trabecular bone cultures from 21-month old rats produced as many cells as cultures from four-month old rats, whereas the amount of trabeculae put into culture was much less in aged rats. Moreover, the proliferation rate in secondary culture was significantly increased in 21-month old rats. Similar responses to calcitriol were observed in bone marrow and trabecular bone cells from aged and younger mature rats, while cAMP responses to PTH were decreased in cells from aged rats. Our data confirm the age-related decrease in the FCFU efficiency of the bone marrow and show a stimulated proliferation of trabecular bone cultures from 21-month old rats that could be seen either as the result of the inhibition in vivo of the response to a signal to proliferate, or as a rebound response to factors present in the serum-enriched medium and lacking in vivo.

Aging↗
PubMed1991

CD71 phenotype and the value of gallium imaging in lymphomas.

Tumor cells of 14 cases of non-Hodgkin lymphomas and 2 cases of Hodgkin disease were tested for the presence of the transferrin receptor (CD71) by flow cytofluorimetry before 67gallium imaging. It appeared that expression of CD71 phenotype was closely related to the positivity of gallium scan before therapy. We feel that this test is able to predict the avidity for 67gallium and the clinical implications are discussed.

Bone Marrow↗
PubMed1991

Changing pattern of CD5+ CD20+ double positive lymphocytes with ageing and cytotoxic chemotherapy.

In this cross-sectional clinical study, it was found that two subtypes of CD5+ B-lymphocytes existed either with CD5-high and CD20-low or CD5-low and CD20-high expression, as determined by dual fluorescence analysis with fluorochrome-labeled monoclonal antibodies on a FACScan flowcytometer. In the normal healthy subjects (n = 20), the CD20 positive cells could be broken down into 3 subsets: CD5(2+) CD20+, 25.4 +/- 3.0% (mean +/- S.E.M.), CD5+ CD20(2+), 18.4 +/- 2.4% and CD5- CD20(2+), 56.2 +/- 2.7%. Similar values were observed in a group of patients (n = 29) suffering from a wide variety of benign or untreated malignant disorders. The CD5(2+) CD20+ subset was typically related to age (Spearman coefficient of correlation rho = 0.77, P less than 0.001 in healthy subjects and rho = 0.46, P = 0.02 in pathological cases). The CD5+ CD20(2+) subpopulation was a salient feature of newborns and little infants (n = 6, 75.4 +/- 2.4%, P less than 0.01). The CD5- CD20(2+) subset was characteristically depressed in patients treated with cytotoxics (n = 21, 41.2 +/- 3.6%, P = 0.001). As far as cytotoxic chemotherapy may represent a model of accelerated ageing, it is worth noting that, in patients treated with cytotoxics, the CD5 CD20 pattern was frequently disturbed in a hyperyoung or hyperaged picture. That age and cytotoxics can affect CD5 expression on CD20+ lymphocytes, suggests some specific B-dysregulation and should be put together with the known emergence of autoantibodies, paraproteinemias and lympho-plasmocytic tumors with age and chemotherapy.

Adult↗
PubMed1990

Effects and interactions of 17 beta-estradiol, T3 and 1,25(OH)2D3 on cultured osteoblasts from mature rats.

Osteoporosis being frequently associated with hyperthyroidism and, mostly after menopause, with deficiency in estrogens, we tried to elucidate the interactions of estrogens and triiodothyronine (T3) with calcitriol by using cultured osteoblast-like cells obtained from mature rat bone. The tested parameters included [3H]thymidine incorporation, evaluation of the alkaline phosphatase activity of the cell layer and osteocalcin production in the culture medium. At physiological concentrations, 17 beta-estradiol and T3 stimulated alkaline phosphatase activity, did not enhance osteocalcin production and slightly inhibited [3H]thymidine incorporation. At higher concentrations, 17 beta-estradiol decreased the alkaline phosphatase and osteocalcin response to calcitriol whereas T3, although decreasing alkaline phosphatase activity, markedly increased the osteocalcin secretion elicited by calcitriol. These observations emphasize the complex physiology of osteoblasts and confirm different behaviors of alkaline phosphatase and of osteocalcin as markers of bone turnover.

Alkaline Phosphatase↗
PubMed1990

Leukocyte and lymphocyte subsets after a short pharmacological stress by intravenous epinephrine and hydrocortisone in healthy humans.

Nine healthy volunteers received epinephrine and hydrocortisone intravenously in order to assess the typical acute response to a brief stress, of leukocyte and lymphocyte subsets, acute phase reactants and lymphocyte reactivity to T and B mitogens. At 10 min., all leukocyte subsets were increased, especially mononuclear cells. At 1 hour, moderate lymphopenia and monocytopenia occurred. At 6 hours, neutrophilia and eosinopenia were observed. During the lymphocytic early wave, all the lymphocyte subset counts increased, particularly T-suppressive/cytotoxic and natural killer cells. As a consequence, the percentage of T cells decreased and the CD4/CD8 ratio fell. No changes in acute phase reactants occurred over the 24 hours of the study. All leukocyte and lymphocyte subsets were normalized and mitogen reactivity was unchanged 24 hours after the stress. These typical shifts in leukocyte subsets could probe the adrenocortical and medullary response to an environmental stressor.

Acute-Phase Proteins↗
PubMed1990

[Pseudotumor cerebri induced by danazol].

Case report of a 39-year-old woman treated by Danazol for a paroxystic nocturnal hemoglobinuria who developed benign intracranial hypertension and sclerosing cholangitis. Bilateral papilloedema cleared 4 weeks after Danazol was stopped. Twelve similar cases have already been reported in the literature. Danazol should be added to the list of drugs potentially inducing pseudo-tumor cerebri.

Adult↗
PubMed1989

Decreased basal and stimulated thyrotropin secretion in healthy elderly men.

To delineate the effects of aging on basal and stimulated TSH secretion, we studied the 24-h profile of plasma TSH levels and the TSH response to TRH stimulation (200 micrograms TRH, iv) in eight healthy elderly men, aged 67-84 yr, and eight normal young men, aged 20-27 yr. Subjects with thyroid antibodies against microsomal or thyroglobulin antigens were excluded. During the 24-h study, blood was sampled at 15-min intervals. TSH levels were measured by an ultrasensitive immunoradiometric assay. Sleep was polygraphically monitored, and circadian and pulsatile TSH variations were quantified using specifically designed computer algorithms. In older men, the 24-h mean TSH concentration was approximately 50% lower than that in young men (0.78 +/- 0.37 vs. 1.43 +/- 0.41 microU/mL; P less than 0.01), but basal T3 levels were only slightly lower (93 +/- 12 vs. 115 +/- 16 ng/dL; P less than 0.02), while basal T4 levels were normal. The normal diurnal variation of TSH levels, with a nocturnal acrophase and an afternoon nadir, as well as the pulsatile nature of TSH release were preserved in elderly men. When expressed in microunits per mL, the amplitude of these temporal variations was reduced in elderly men compared to that in younger subjects. However, when expressed in relation to the mean TSH levels, the amplitudes of diurnal and pulsatile variations were similar in both groups of subjects. TRH-induced TSH secretion was lower in old than in young men (area under the curve, 15.9 +/- 6.3 microU/mL.10 min in elderly men vs. 42.0 +/- 16.6 microU/mL.10 min in young men; P less than 0.002). However, the TRH-induced elevations of T3 and T4 were of similar magnitude in both groups. These results indicate that in healthy elderly men, the overall 24-h TSH secretion is decreased, and the pituitary is less responsive to stimulation by TRH. However, the chronobiological modulation is preserved. These alterations could reflect an adaptative mechanism to the reduced need for thyroid hormones in old age. The thyroid keeps an intact capacity to respond to acute increases in TSH concentrations.

Adult↗
PubMed1988

Effects of iodine intake on thyroid secondary lysosomes after subtotal thyroidectomy.

This study tested the effects of different iodine intakes on thyroid ultrastructure and function in thyroid remnants after subtotal thyroidectomy (sub-tx). Removal of most of the thyroid gland causes an elevation of endogenous TSH, which chronically stimulates the residual tissue. Male Sprague-Dawley rats were divided into three groups; Low Iodine Group (LIG), Moderate Iodine Group (MIG), and High Iodine Group (HIG). There was no significant difference among total thyroid weights removed by sub-tx, but thyroid remnant weights and TSH levels were higher at death (6 weeks after sub-tx) in LIG than in MIG and HIG. Total specific activities of cathepsin D and of arylsulfatase A in the sedimentable and nonsedimentable subcellular fractions were at least 38% lower in LIG than in MIG and HIG. The ratio between relative follicular volume and colloid volume determined by morphometry was higher in LIG than in MIG and lower in HIG than in MIG. Ultrastructurally, the relative volume occupied by secondary lysosomes was higher in HIG than in MIG, whereas the number of secondary lysosomes was not higher in LIG than in controls. Autoradiographic studies with 125I revealed that a large part of the radioactivity was in thyroid cell secondary lysosomes in MIG and HIG when radioiodine was injected 3 weeks before death. It is concluded that after sub-tx, iodine 1) regulates the weight of thyroid remnants, perhaps only indirectly through TSH, 2) modulates the number of secondary lysosomes in thyroid cells, and 3) slows down the turnover of secondary lysosomes. An iodine-deficient regimen impedes the secondary lysosomes to increase. Because of these findings, we postulate that chronic TSH stimulation along with a possible toxic role of iodine after sub-tx could induce an accumulation of lysosomal bodies.

Animals↗
PubMed1987

Effect of age, sex and health status on human lymphocyte functions: demonstration of a sex-related defect in suppressor cell function.

The mitogenic response of human lymphocytes and the short-lived suppressor cell function on concanavalin A response were studied as dependent variables in 194 patients using multiple regression analysis, with health status and sex as dummy variables, and age as an explicative one. This study confirms a decrease of the lymphocyte functional response to mitogens with aging. A sex-related defect in suppressor cell function is put forward in females independently of age. An inverse linear relationship is found between the functional response to pokeweed mitogen (T and B mitogen) and suppressor cell function in males but not in females. No such relationship is found with the pure T mitogens (Con A and phytohemagglutinin-A). The present study suggests that a defect in short-lived suppressor cells can play some role in the greater incidence and prevalence of autoimmune diseases in women while the depressed lymphocyte response of old people cannot be explained by modifications of the activity of these suppressor cells.

Adult↗
PubMed1987

Thyroid, lipid and other biological variables in elderly patients with asymptomatic autoimmune thyroiditis: a statistical analysis.

Asymptomatic autoimmune thyroiditis (AAT), especially prevalent in elderly women and associated with the presence of thyroid antibodies (HT), is recognized as a precursor of hypothyroidism and is an intermediate between euthyroidism and hypothyroidism. This paper is concerned with the possible modifications of biochemical variables - some of which are not directly related to the thyroid - in patients with AAT. Thirty-seven serum factors were investigated in euthyroid, AAT, and HT subjects over 69 years of age. They were thyroglobulin; microsomal, gastric and adrenal antibodies; LE cells, and thyroid, lipid and immunological variables linked to the inflammatory process. In women the only variable, other than those related to the thyroid, which showed any modification in the AAT state was the cholesterol level. Wholly different observations were made in men, stressing the necessity of separate analysis of male and female data: the thyroid-related variables which were modified in the AAT state are not the same as in women, the cholesterol is not increased but triglycerides, HDL, albumin and inflammatory variables are modified. Furthermore, the lipid variables showed an unexpected age dependency in AAT, but not in euthyroid women (between 69-90 years of age).

Aged↗
PubMed1986

Formation of intracellular lumina in dispersed pig thyroid cells.

Intracellular cavities characterized by the presence of microvilli have been identified in dispersed thyroid cells. These structures resembling follicular lumina were called intracellular lumina or ICL. Freshly dispersed cells did not contain ICL. At 37 degrees C, ICL formation was a rapid process. After 60 min of incubation, ICL were present in 15 to 20% of the cells; the number of ICL remained rather constant during 3 to 4 h of incubation. In the presence of thyrotropin, the number of ICL increased with time to reach a value ranging from 40 to 60 ICL per 100 cells after 4 h of incubation. ICL formation was also increased in the presence of dibutyryl cyclic AMP (2 mM). Vinblastine (30 microM), a microtubule-disrupting agent and monensin (30 microM), an ionophore inhibiting Golgi functions blocked the formation of ICL in control and thyrotropin-stimulated cells. Cycloheximide (0.5 mM) and puromycin (0.5 mM) did not inhibit ICL formation in either control or thyrotropin stimulated cells. The iodination capacity of ICL was studied by quantitative electron microscopic autoradiography after incubation of thyroid cells with 125 I-iodide for 2 to 60 min. Radioiodinated products appeared first in ICL. After 1 h of labeling autoradiographic grains were found mainly in ICL (60-70%) and over the cytoplasm. The labeling of ICL was heterogeneous; ICL contained either few or numerous overlapping grains. Whatever the labeling time, a high proportion of ICL (70-80%) were labeled. The labeling of ICL as well as the labeling over the cytoplasm was increased in the presence of thyrotropin and almost completely inhibited in the presence of an iodide trapping inhibitor: sodium perchlorate. Pulse-chase experiments revealed that thyrotropin stimulated the discharge of 125 I-labeled material from ICL.

Animals↗
PubMed1985

Immune senescence: effect of age, sex and health on human blood mononuclear subpopulations.

The respective influence of age, sex and health states on peripheral blood mononuclear subpopulations has been investigated in 194 institutionalized subjects. The "ill group' includes patients with various diseases and the "reference group' was referred to admission criteria for immuno-gerontological disease. A decline of total mature T-cell (OKT3) and helper T-cell (OKT4) proportions with ageing has been found only in the ill group and remains stable in the reference group. This age-dependent decline should represent either a susceptibility for illness or a consequence of higher incidence of illness with ageing. Suppressor-cytotoxic (OKT8), B- and T-activated (OKIa1), null (OKM1), and early E-rosette forming cells do not vary with ageing in both groups. It has been established previously that women have higher values of the percentages of early E-rosette forming cells.

Aged↗