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G Pasolini

Publications and source records attributed to G Pasolini.

At least 19 recordsLinked to original sources
PubMed2001

Identification of Fas-L-expressing apoptotic T lymphocytes in normal human peripheral blood : in vivo suicide.

Fas-L molecules expressed by in vitro stimulated T cells may be critically involved in suicidal activation-induced cell death (AICD) of such cells through engagement of their Fas receptors. A similar suicide of T cells was postulated to occur even in vivo, to eliminate dangerous activated lymphocytes; however, the demonstration of suicidal AICD of T cells in healthy humans in vivo is still lacking. We therefore investigated the possible occurrence of Fas-L-linked suicidal apoptosis of T cells in normal human peripheral blood. For this purpose, we took advantage of immunoelectron microscopy, which allows simultaneous visualization of the morphological apoptotic cellular changes together with surface expression of Fas-L molecules. Very few T lymphocytes were observed showing the ultrastructural features of apoptotic lymphocytes; these occasional apoptotic T cells, together with the majority of the normal T cell population, expressed the Fas molecule on the plasma membrane, as expected. Interestingly, the apoptotic cells were also Fas-L-positive, whereas normal T cells were Fas-L-negative. Such Fas-L-associated T cell suicide operating in vivo in healthy individuals is presumably able to suppress immune responses and prevent autoreactivity, thus maintaining the homeostasis of human blood.

Apoptosis↗
PubMed2000

Changes in HDL-cholesterol and lipoprotein Lp(a) after 6-month treatment with finasteride in males affected by benign prostatic hyperplasia (BPH).

Androgen effects on lipoproteins, mainly high density lipoprotein (HDL), could be exerted by a direct interaction of testosterone (T) or dihydrotestosterone (DHT) with liver androgen receptors. To assess if T needs to be converted into DHT to affect lipid metabolism, 13 patients were studied, affected with benign prostatic hyperplasia (BPH) and treated with an inhibitor of 5 alpha-reductase (finasteride). They were compared with 15 untreated controls. At baseline and after 3 and 6 months of therapy, each patient was evaluated as for lipoprotein and hormone concentrations, as well as for nutritional status. Body composition was assessed by anthropometry and bio-impedance analysis (BIA). Treatment was associated with a significant increase of HDL-cholesterol (HDL-C), mainly HDL3 subclass, and lipoprotein(a) (Lp(a)), as well as a decline of DHT, whereas no significant changes were apparent for T, estradiol (E2), sex hormone binding hormone (SHBG) and body composition indexes. However, no significant associations between DHT and lipid relative changes were apparent at bivariate correlation analysis. This finding was confirmed by comparing patient subsets identified by cluster analysis, according to HDL subclass individual responses. Rather, a slight association with E2 for HDL2 (positive) and HDL3 (negative) was found. In conclusion, finasteride can modify HDL and Lp(a) concentrations. However, by the data, these effects cannot be definitively attributed to the changes in DHT synthesis induced by finasteride, since a direct and non-specific interference of the drug on liver metabolism cannot be excluded.

Aged↗
PubMed2000

Aging-related decline of gonadal function in healthy men: correlation with body composition and lipoproteins.

OBJECTIVE: To assess if androgen decline in physiological aging contributes to the concomitant changes in body composition and lipoprotein levels. DESIGN: Cross-sectional, observational study. SETTING: A university-based outpatient center. SUBJECTS: The study comprised 206 healthy volunteers (aged 18-95 years). MEASUREMENTS: Blood samples were drawn after an overnight fast for the assay of hormones (free testosterone (FT), estradiol (E2), and sex hormone-binding globulin (SHBG)) and lipids (total cholesterol, triglycerides, high-density lipoprotein cholesterol, and lipoprotein Lp(a)). At the same time, body composition was assessed by both anthropometry (fat mass percentage (FM%) estimated from four measures of skinfold thickness using the Durnin and Womersley equation and the Siri equation) and by bioimpedance analysis (FM% estimated using the Segal or Deurenberg equations, respectively, for subjects younger or older than 62 years). RESULTS: A significant age-related decline was found for FT and E2 concentrations, whereas SHBG levels were related positively with age. No significant association was apparent between hormonal changes and the concomitant modifications of body composition and lipoproteins. Only SHBG showed a significant inverse association between FM% and the waist-to-hip ratio, independent of age. The comparison between older hypogonadal (with FT levels below the lower limit of the normality range assessed in younger subjects) and eugonadal men did not show any significant differences in body composition or lipid profile. CONCLUSIONS: This study suggests that, in men, androgen decline caused by normal aging does not significantly affect some targets of testosterone action, such as body composition and lipid metabolism. Therefore, androgen supplementation in hypogonadal older men cannot be expected to influence nutritional status and body composition to the same extent that it does other main targets of testosterone action, such as sexual activity and muscle strength. However, we cannot exclude that selected subsets of older patients with low testosterone levels, especially if affected by catabolic disease, could benefit from the effects of androgen administration on nutritional status.

Adolescent↗
PubMed1999

Reduced production of both Th1 and Tc1 lymphocyte subsets in atopic dermatitis (AD).

An imbalance of interferon-gamma (IFN-gamma)-bearing CD4+ T (Th1) cells in the pathogenesis of AD is well recognized; however, a possible role in AD for CD8+ T cells secreting Th1-like cytokines (Tc1) has not been properly addressed. In this study, two- and three-colour FACS analysis allowed us to discriminate the Th1 from the Tc1 subset. AD patients had half the number of IFN-gamma-producing circulating T cells (P < 0.005; 13.6 +/- 1.9% (mean +/- s.d.)) compared with normal donors (25.0 +/- 2.4%). Specifically, both Th1 (4.8 +/- 0.7%) and Tc1 (8.1 +/- 1.1%) cells in AD were decreased compared with Th1 (8.8 +/- 0.8%) and Tc1 (15.0 +/- 1.5%) cells in controls. Moreover, at the mRNA level, the ratios of IFN-gamma/IL-4 and IFN-gamma/IL-10 were lower in cells from AD patients compared with controls. In conclusion, the decrease of IFN-gamma-producing T lymphocytes in AD is due to a reduction in both Th1 and Tc1 IFN-gamma-secreting cells; this may not only contribute to the over-production of IgE, but also explain the high incidence of cutaneous infections observed in AD patients.

CD8-Positive T-Lymphocytes↗
PubMed1997

Allergic reactions due to glove-lubricant-powder in health-care workers.

Eight glove-wearing hospital personnel were evaluated for suspected type I-like allergic manifestations due to corn-starch powder. All subjects were clinically examined, the presence of atopy was assessed by administration of a questionnaire, the on-off test was verified (the clinical feature behavior was verified with regard to the beginning and the cessation of the work shift), levels of specific serum IgE for maize and latex were measured, and prick tests for the same allergens were performed. The on-off test was positive for everyone. The symptom associated with glove use was urticaria, which was also associated in one case with intermittent dyspnea and in another with oculorhinitis, angioedema, and asthma. Five workers were atopic. The serum IgE test found three positive responses to maize, three positive responses to both latex and maize, and two negative responses to both. However, in the two patients testing negative to IgE, the prick tests were positive: one for maize and the other for both maize and latex. All workers evaded further relapses by avoiding exposure to powdered gloves. There is general agreement that corn-starch powder may cause irritant dermatitis and that it may be a vehicle for other allergens. This study seems to suggest that corn-starch powder may act as a type I allergen itself. Further studies on a larger number of subjects and further research on the chemical properties of corn-starch powder, in particular on its protein content, are needed to confirm this hypothesis.

Adult↗
PubMed1997

Effects of aging on dehydroepiandrosterone sulfate in relation to fasting insulin levels and body composition assessed by bioimpedance analysis.

Insulin can inhibit dehydroepiandrosterone (DHEA) biosynthesis in humans, as suggested by several studies performed in induced or spontaneous hyperinsulinemia. The increased insulin resistance documented throughout aging, with its accompanying hyperinsulinemia, may contribute to the age-related decline in DHEA synthesis. The aim of this study was to assess if the aging-related differences in DHEA sulfate (DHEA-S) serum levels can be associated with differences in fasting insulin levels, as well as body composition. Two hundred fifty-two healthy subjects of both sexes aged 19 to 90 years with a body mass index (BMI) less than 30 (mean +/- SD, 23.5 +/- 2.4) were studied DHEA-S and insulin serum levels were determined by a radioimmunologic procedure; body composition was assessed by anthropometry (fat mass percentage [FM%] estimated from four skinfold thicknesses by Durnin and Womersley and Siri equations [FM%-SKF]) and by bioimpedance analysis (BIA) (FM% estimated by equations developed by Segal et al and Deurenberg et al for subjects < and > 62 years, respectively [FM%-BIA]). DHEA-S levels were significantly and inversely related to age in both sexes. No significant aging-related differences were found in fasting insulin levels, although a trend toward an increase was apparent in the women on simple regression analysis. No significant associations were found between DHEA-S and insulin levels. As for body composition, a positive relationship to age was apparent for FM%-SKF, FM%-BIA, and waist to hip ratio (WHR), whereas BMI and phase angle ([PA] a bioelectric parameter considered an index of the ratio between intracellular and extracellular water) were inversely related to age. Fasting insulin levels were positively related to FM% as estimated by both BIA and anthropometry, independently of age in both sexes; in addition, a positive correlation with WHR and with the subscapular to triceps skinfold thickness ratio (SS/TS) was found in men and women, respectively. No significant correlation was apparent between DHEA-S and body composition indices in men, whereas in women a slight negative correlation between DHEA-S and WHR was documented, and was still significant after adjustment for age and fasting insulin. Stepwise multiple regression analysis confirmed that DHEA-S levels are not related to fasting insulin, but are independently related to age and, in women only, to WHR. Our study suggests that the DHEA-S decline due to aging is independent of fasting insulin, at least in healthy, non-obese people. In addition, it is not related to the aging-dependent changes in body composition in terms of FM% and fat-free mass (FFM) percentage (FFM%). Only in women could changes in fat distribution be slightly associated with DHEA-S decline, although such a relation cannot be accounted for by changes in insulin levels.

Adolescent↗
PubMed1997

Evaluation of circulating galanin levels after exercise-induced pituitary hormone secretion in man.

The neuropeptide galanin (GAL) is widely distributed in the central and peripheral nervous systems, anterior pituitary, and adrenal medulla. GAL is colocalized with corticotropin (ACTH) in the human pituitary and with epinephrine (E) and norepinephrine (NE) in chromaffin cells of the adrenal medulla. The function of GAL in peripheral tissues is not known, although the presence of the peptide in corticotrophs and the adrenal gland suggest that it participates in stress responses. In the present study, we investigated whether GAL is cosecreted with ACTH during activation of corticotrophs by an acute physical exercise test. Circulating levels of GAL and pituitary hormones were measured in healthy exercise-tested and control male subjects. Blood samples were collected during basal conditions, maximal power output (MPO), and the recovery period. Control subjects were sampled during the resting condition. The pituitary response to exercise was characterized by a significant increase in ACTH plasma levels (peak value 13.28 +/- 2.19 v 6.68 +/- 1.01 pmol/L, P < .05) and growth hormone (GH) serum levels (peak value, 14.53 +/- 5.59 v 0.29 +/- 0.1 microg/L, P < .02), with the peak in hormone levels detected 15 minutes after the end of exercise. No change in circulating prolactin (PRL) levels was detected. An expected significant increase in plasma levels of both E (peak value, 1,574.41 +/- 403.31 v 267.44 +/- 60.03 pmol/L, P < .01) and NE (peak value, 7,275.25 +/- 955.80 v 961.51 +/- 168.40 pmol/L, P < .01) was also observed. Plasma GAL levels were not affected by the acute exercise test, with the levels being comparable to baseline during the exercise test and the recovery phase. At any sample time, GAL values were comparable between exercise-tested and control subjects. These data show that despite the colocalization of GAL and ACTH within the same pituitary cells, the two peptides are not coreleased in response to stress resulting from acute physical exercise. Furthermore, pituitary GAL seems not to be involved in the stimulation of GH secretion in exercise-tested subjects. The results also indicate that GAL is not coreleased with E or NE in response to the exercise-induced stress condition.

Adrenocorticotropic Hormone↗
PubMed1996

Macrophages, but not Langerhans cell-like cells of dendritic lineage, express the CD36 molecule in normal human dermis: relevance to downregulatory cutaneous immune responses?

The CD36 molecule has been shown to be associated with subsets of peripheral blood monocyte/macrophages and, in cells isolated from either ultraviolet (UV)-irradiated or diseased skin, to induce downregulatory immune responses. Although macrophages are certainly present within normal human dermis, whether they normally express CD36 is still a matter of debate. In this study, we investigated dermal CD36-expressing macrophages in situ using the gold immunoelectron microscopic technique on tissue ultracryosections. This is a very sensitive and specific method, and its results clearly reflect the in vivo immunophenotypic constitutive situation. Macrophages in normal human dermis were variously shaped from round to dendritic and were localized either immediately beneath the epidermis, in perivascular areas, or in intervascular zones. Macrophages showed consistent gold-positive staining on their cell surface. In contrast, other dermal cells, including fibroblasts, lymphocytes, and mast cells, as well as dermal fibers, were not decorated with gold; dermal Langerhans cell-like dendritic cells (LC/DC), though they did show gold labeling in some intracytoplasmic organelles, did not show any gold particles along their plasma membranes. Therefore, although macrophages in normal human dermis exhibit variability with regard to their localization and shape, they regularly and constitutively expressed CD36. CD36 molecules may be considered a useful marker for macrophages in normal human dermis and may furthermore confer on macrophages, or a subpopulation thereof, intriguing functional properties (e.g., downregulatory capacity versus upregulatory capacity subserved by LC/DC) within the cutaneous immune system.

Antibodies, Monoclonal↗
PubMed1996

Effects of androgen suppression by gonadotropin-releasing hormone agonist and flutamide on lipid metabolism in men with prostate cancer: focus on lipoprotein(a).

No clear relation between lipoprotein(a) [Lp(a)] and endogenous gonadal hormones has been demonstrated. In this study, we compared the effects on Lp(a) of pharmacological castration in 50 patients with prostate cancer who were undergoing therapy with a gonadotropin-releasing hormone agonist (goserelin), with effects on 58 age-matched controls. We also studied 16 untreated patients under baseline conditions and after 3 months of therapy with goserelin alone or combined with an antiandrogen (flutamide). Neither cross-sectional nor prospective studies showed any significant effects of therapy on Lp(a). However, cluster analysis identified a subgroup of patients showing slight but significant increases in Lp(a) concentrations, as well as greater declines of testosterone and estradiol, suggesting that androgen, like estrogen, can exert some slight, though not easily detectable, influence on Lp(a).

Aged↗
PubMed1996

Keratinocytes resident in normal human skin constitutively express, at low levels, the intercellular adhesion molecule-1. An in situ immunoelectronmicroscopy study.

The expression of intercellular adhesion molecule-1 (ICAM-1) on keratinocytes (KC) was previously demonstrated in biopsies from various inflammatory skin lesions. KC were, however, found virtually ICAM-1 negative, in normal skin, when the same immunocytochemical techniques were employed. By contrast, epithelial cells resident in different organs constitutively express ICAM-1, albeit weakly. The aim of the present study was to use an immunostaining system more sensitive than the conventional immunocytochemistry, namely the in situ immunogold labelling of ultracryosections, to investigate the constitutive ICAM-1 expression by resting KC in normal skin, in vivo. The semiquantitative analysis performed on 500 resident KC, visualized within tissue ultracryosections of normal human skin, revealed that gold granules were present long the cell membrane in a small percentage (14.6%) of resident KC. The density of gold particles (10 nm sized) observed on the cell surface per KC section was as scarce as 13.72 +/- 4.6 (mean +/- standard deviation), although highly significant when compared with controls (P < 0.005). This indicates the presumably low expression of ICAM-1 moieties on the plasma membrane of this KC subset. This ICAM-1 expression could be important in modulating the trafficking to and from normal epidermis of migrating Langerhans cells and occasional leucocytes. The fact that the ICAM-1 expression on KC in normal skin is limited can be considered favourable, because it can account for the prevention of inappropriate KC/leucocyte interactions in the resting cutaneous environment.

Epidermis↗
PubMed1995

Lipoprotein Lp(a) and cerebrovascular disease in the elderly: correlations with the severity of extracranial carotid atherosclerosis assessed by ultrasonography.

High levels of lipoprotein Lp(a) are related to cerebrovascular disease clinical manifestations, as well as to the severity of extracranial carotid atherosclerosis assessed by ultrasonography. In order to investigate the relationship of Lp(a) to the severity of carotid atherosclerosis in the elderly, 100 subjects, aged 78.5 +/- 0.6 yrs underwent an echo-color-doppler scanning of carotids; atherosclerosis severity, assessed as maximum percentage stenosis, presence of complicated plaque and Intima-Media Thickness (IMT), was related to Lp(a) levels, assayed by an immunoenzymatic procedure. A slight association between Lp(a) and CVD clinical manifestations was apparent only in subjects under 78 yrs and for Lp(a) values above 25 mg/dL. Lp(a) levels were not related either to the degree of stenosis, the presence of complicated plaque, or IMT. As for other selected risk factors, while no relationship was found for clinical CVD and IMT, the maximum percentage of stenosis and the presence of complicated plaques were positively related to LDL-cholesterol in subjects under 78 yrs. We can conclude that Lp(a), albeit unrelated to the severity of extracranial vessel atherosclerosis, maintains a role as cerebrovascular risk factor in the elderly, being slightly related to clinical manifestations; however its discriminant power is lower than in middle-aged people and further decreases throughout ageing.

Aged↗
PubMed1994

Correlation between plasma lipoprotein Lp(a) and sex hormone concentrations: a cross-sectional study in healthy males.

High concentrations of lipoprotein Lp(a) have been related to atherosclerotic disease, both at coronary and cerebrovascular levels. Although Lp(a) levels are under a strict genetic control, being inversely related to the molecular weight of apo(a) isoforms, an interference of endogenous sex steroids on Lp(a) metabolism has been hypothesized. The aim of this study was to investigate the interrelationship between plasma Lp(a) and sex hormone concentrations in 98 healthy males, controlled as for their nutritional status by anthropometric measurements. Statistical evaluation was performed employing simple and multiple stepwise regression analysis. No significant correlation was found between Lp(a) levels and fT, E2 and gonadotropins, while they were positively and independently related to LDL-cholesterol and DHEA-S. As for the other lipoproteins, a positive correlation between HDL-cholesterol and E2 and an inverse correlation between triglycerides and SHBG were observed. These data suggest that endogenous testosterone and estradiol do not affect Lp(a) metabolism in males, at least in physiological concentrations. However Lp(a) might be affected by DHEA-S, the most abundant product of the adrenal gland. The positive correlation of HDL-cholesterol to E2 suggests that estrogens play a major role in lipid metabolism also in males, in spite of their low concentrations; more complex to be explained is the finding of an inverse relationship between Tg and SHBG. Further studies are needed in order to clarify the influence of sex steroids on lipid metabolism, mainly on Lp(a), under physiological conditions; population samples homogeneous in terms of apo a isoforms could be the ideal objects of such studies, in order to avoid the great interindividual variability of Lp(a) concentrations.

Adult↗
PubMed1994

A case of trichorhinophalangeal syndrome, type I.

A single case of trichorhinophalangeal syndrome, type I, is reported. The patient manifested the complete triad of the syndrome: thin, sparse, slow-growing scalp hairs; a pear-shaped nose; and cone-shaped epiphysis in some interphalangeal articulations of both hands. In addition, tooth decay, pectus carinatum, lumbar scoliosis, and polycystic ovary were observed. This multisystemic disorder is apparently rare, but its prevalence is probably underestimated in the dermatologic literature.

Abnormalities, Multiple↗
PubMed1993

Melanocytes freshly isolated from normal human skin express the cell membrane receptor for the adhesive glycoprotein thrombospondin.

Thrombospondin (TSP) is an adhesive protein with multiple binding sites, which is able to mediate several cell-to-cell and cell-to-matrix interactions, particularly through its cell membrane receptor (TSP-R). Because human keratinocytes are able to synthesize and express TSP, and as TSP is also localized at the dermal-epidermal junction in normal human skin, we questioned whether epidermal cells are able to bind available TSP, that is, to express TSP-R. To investigate this, we employed gold immunoelectron microscopy on epidermal cells freshly isolated from normal human skin; the TSP-R was detected by OKM5 monoclonal antibody. Epidermal cells showing ultrastructural characteristics of melanocytes were gold-stained on their plasma membrane, whereas keratinocytes, Langerhans cells and lymphocytes were unstained. Although functional studies are clearly necessary to clarify the role(s) played by the TSP-R on the cell surface of melanocytes, it is tempting to speculate that the TSP-R may be important for melanocyte adhesion to the dermal-epidermal junction and to keratinocytes. Such adhesion may not only subserve the steric localization of melanocytes, but also have important implications for those functional activities of melanocytes which have been shown to require close contact between these cells and adjacent keratinocytes and/or basement membrane components.

Antibodies, Monoclonal↗