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Biomedical subjects

C Ferrari

Publications and source records attributed to C Ferrari.

At least 73 records · Page 4Linked to original sources
PubMed1990

Human normal-resting epidermal Langerhans cells do express the type 3 complement receptor.

The expression of CR3 by murine-resting epidermal Langerhans cells (LC) is well established, but CR3 expression by human normal-resting epidermal LC has not yet been demonstrated. In this study, highly sensitive immunostaining techniques, such as immunogold labelling in transmission- and scanning-electron microscopy, were used on freshly isolated, LC-enriched, normal human epidermal cells. Human normal resting epidermal LC were found to be CR3+, since a low but significant number of gold granules labelled the plasma membrane of all the LC observed under transmission-electron microscopy, and all the epidermal cells showing LC morphology as observed by scanning-electron microscopy.

Cell Membrane↗
PubMed1990

Treatment of autonomous thyroid nodules with percutaneous ethanol injection: preliminary results. Work in progress.

Eight patients with autonomous thyroid nodules 2.4-4.3 cm in diameter received percutaneous ethanol injections (PEIs) under guidance by means of ultrasound (US). Sterile ethanol at 95% was injected with a 22-gauge needle and a 7.5-MHz probe with a guide device. Each patient received one or two treatments, with 1-3 mL of alcohol (depending on the nodule size) per treatment, each week for a total of three to six injections per lesion. After a total of 36 injections in all eight patients, there were no complications. Follow-up ranged from 2 to 10 months. After therapy, symptoms subsided and hormonal levels became normal or reached the range of subclinical hypothyroidism. Scintigrams showed that the previously suppressed thyroid tissue had resumed functioning. At US, all nodules had shrunk. PEI was risk free and easy to perform. If these preliminary results are confirmed in a larger study with longer follow-up, the new treatment may become an alternative to surgical or radioiodine ablation of autonomous thyroid nodules.

Adult↗
PubMed1990

Immunogold scanning electron microscopy applied to the study of Langerhans cells immunophenotype.

An immunogold technique in scanning electron microscopy was applied to the detection of Langerhans cell surface CD1a antigen in a heterogeneous human epidermal cell suspension. Scanning electron microscopy investigations performed in the secondary electron imaging mode and in the backscattered electron imaging mode allowed to define Langerhans cell surface morphology and the labeling degree, respectively. In particular, the backscattered electron imaging mode of the scanning electron microscope appeared very useful in identifying colloidal gold particles and, as a result, made it possible to make total counts of the labeled surface antigenic sites. Finally, the combination of secondary electron and backscattered electron signals generated mixed images with the Langerhans cell surface morphology well recognizable together with distinct gold particles. The immunogold labeling in scanning electron microscopy here described represents a highly sensitive method and yields a new improvement in the study of Langerhans cells immunophenotype.

Antigens, Surface↗
PubMed1990

Effects of methimazole treatment on growth hormone (GH) response to GH-releasing hormone in patients with hyperthyroidism.

In vitro studies have demonstrated that thyroid hormones can enhance basal and stimulated growth hormone secretion by cultured pituitary cells. However, both in man and in the rat the effects of high thyroid hormone levels on GH secretion are unclear. The aim of our study was to test the GH response to human GHRH in hyperthyroid patients and to evaluate the effects on GH secretion of short- and long-term pharmacological decrease of circulating thyroid hormones. We examined 10 hyperthyroid patients with recent diagnosis of Graves' disease. Twelve healthy volunteers served as controls. All subjects received a bolus iv injection of GHRH(1-29)NH2, 100 micrograms. Hyperthyroid patients underwent a GHRH test one and three months after starting antithyroid therapy with methimazole, 10 mg/day po. GH levels at 15, 30, 45, 60 min and GH peak after stimulus were significantly lower in hyperthyroid patients than in normal subjects. The GH peak was also delayed in hyperthyroid patients. After one month of methimazole therapy, most of the hyperthyroid patients had thyroid hormone levels in the normal range, but they did not show significant changes in GH levels after GHRH, and the GH peak was again delayed. After three months of therapy with methimazole, the hyperthyroid patients did not show a further significant decrease in serum thyroid hormone levels. However, mean GH levels from 15 to 60 min were significantly increased compared with the control study. The GH peak after GHRH was also earlier than in the pre-treatment study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Subsets of keratinocytes and Langerhans' cells express epitopes associated with suppressor-inducer capabilities in resting normal human epidermis.

In recent years two cell populations with down-regulatory immune capabilities have been identified in murine epidermis. The present report demonstrates that even in human epidermis at least two populations of cells expressing suppressor-inducer phenotypes (i.e. CD45R-positive) exist, namely small subsets of keratinocytes and Langerhans' cells, respectively. Highly specific and sensitive 5-nm colloidal gold-immunoelectronmicroscopic techniques were carried out using anti-CD45R monoclonal antibodies, on freshly isolated crude epidermal cell suspensions, and 4000 cells were scrutinized in the electron microscope. Over 2% of the total epidermal cell population was CD45R+. Subpopulation analysis revealed that approximately 2% of keratinocytes and about 5% of the total Langerhans' cell population showed strong gold-plasma membrane staining, whilst the remaining epidermal cells were absolutely negative. Heterogeneity of staining together with this somehow surprising distribution of CD45R positivity on non-lymphoid epidermal cells was confirmed by the negative controls. These CD45R+ Langerhans' cells and keratinocytes are clearly candidates for the cells which have been functionally demonstrated as being capable of inducing down-regulation responsiveness in the human epidermis. However, functional investigations are needed to clarify the roles of the CD45R+ keratinocyte and Langerhans' cell subsets in the modulation of cutaneous immune responses.

Antigens, CD↗
PubMed1989

Inactivation of skeletal-muscle UDP-glucose pyrophosphorylase by reaction with carboxylate-directed reagents.

Skeletal-muscle UDP-glucose pyrophosphorylase is inactivated by reaction with 2-ethoxy-N-(ethoxy-carbonyl)-1,2-dihydroquinoline (EEDQ) and 1-(3-dimethylaminopropyl-3-ethylcarbodi-imide (EDAC), two reagents specific for carboxylate groups. The former reagent is a more effective inactivator than EDAC. Although no evidence of reversible enzyme-reagent complexes of the affinity-labelling type was obtained by kinetic analysis of the inactivation, the selective protection of UDP-glucose pyrophosphorylase activity against inactivation by EEDQ in the presence of uridine substrates is indicative of an active-site-directed effect. The results are consistent with the hypothesis that EEDQ modifies a single carboxylate group located in a hydrophobic domain close to the substrate-binding site, leading to enzyme inactivation. In contrast, the reaction between UDP-glucose pyrophosphorylase and EDAC appears to involve a different region of the enzyme.

Animals↗
PubMed1989

A multiple-staining ultrastructural procedure simultaneously detecting three membrane antigens on suspended cells by monoclonal antibodies and pre-embedding immunogold labelling.

A triple ultrastructural immunogold staining method for the simultaneous demonstration of three surface antigens of peripheral blood mononuclear cells at the electron microscope level is described. A six-step pre-embedding immunoelectron microscopy procedure was developed, using commercially available reagents. The CD11b antigen was first detected, through a two-step (indirect) method with 40 nm-sized gold particles; after a blocking step, the HLA-DR surface antigen was subsequently detected, through a two-step (biotin-streptavidin) method with 20 nm-sized gold particles; the CD4 antigen was finally detected, through a one-step (direct) method, using 5 nm-sized gold particles. Electron microscopic examination revealed firstly the presence of a triple-labelled cell subpopulation, which showed gold granules of the three sizes simultaneously decorating the cell membrane. Thus, the cells of such a subset simultaneously expressed the three antigens investigated. In contrast, either gold particles of only one size or no gold particles were observed on the cell surface of other subpopulations. This technique is a model demonstrating the importance of varying the size of particles in pre-embedding gold immunoelectron microscopy for a better analysis of the expression of surface antigens in isolated cells.

Antibodies, Monoclonal↗
PubMed1989

The drug MK-801 attenuates the development, but not the expression, of long-term potentiation and stimulus train-induced bursting in hippocampal slices.

Recent studies have demonstrated that (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801), a use-dependent blocker of N-methyl-D-aspartate (NMDA)-activated membrane channels, attenuates the development of long-term potentiation in vitro and kindling in vivo. Both of these phenomena are manifestations of physiological plasticity related to behavioural states and the results of these studies add to the gathering evidence for the involvement of the NMDA receptor/channel system in such processes. In the present experiment, slices of hippocampus, prepared from rats, were electrically stimulated to produce either long-term potentiation of the CA1 population spike or stimulus train-induced epileptiform bursting in area CA3. At 10 microM, MK-801 attenuated the development of long-term potentiation, but had no attenuating effect upon the previously-potentiated population spike. Similarly, 10 microM MK-801 attenuated the development of epileptiform activity in area CA3, but had little or no effect on the previously-established bursting in area CA3. These data support the suggestion that MK-801 exerts an antiepileptogenic, but not an anticonvulsant effect, at concentrations which also inhibit long-term potentiation.

Animals↗
PubMed1989

Effects of blood sampling procedures, grouping and adrenal stimulation on stress responses in the growing pig.

Changes in the blood and the behaviour of 14 growing pigs from 4 different litters were evaluated under different experimental conditions of blood sampling, grouping and adrenal stimulation. The results showed that the different techniques of blood sampling influenced lactic dehydrogenase (LDH) and creatine kinase (CK) activities. Cortisol, proteins and CK levels were negatively correlated with social hierarchy after regrouping. Cortisol was also correlated with total activity levels. Adrenal stimulation by adrenocorticotropic hormone (ACTH) administration caused a sharp increase in plasma cortisol levels. However, plasma glucose, plasma proteins and total leukocyte counts were not affected by the ACTH treatment.

Adrenal Cortex↗
PubMed1989

Adhesion molecules on the plasma membrane of epidermal cells. I. Human resting Langerhans cells express two members of the adherence-promoting CD11/CD18 family, namely, H-Mac-1 (CD11b/CD18) and gp 150,95 (CD11c/CD18).

The CD11/CD18 family of leukocyte adhesion-promoting proteins is comprised of three members, each composed of a shared beta subunit (CD18) noncovalently associated with unique alpha subunits (CD11a, CD11b and CD11c respectively). Such three heterodimers, named LFA-1 (CD11a/CD18), H-Mac-1 (CD11b/CD18) and gp150,95 (CD11c/CD18), are involved in mediating leukocyte adhesion in virtually all phases of the immune responses. Since Langerhans cells are regarded as cutaneous leukocytes, we investigated the expression of the members of the CD11/CD18 family on Langerhans cells. A vast series of immunostaining procedures was carried out, using monoclonal antibodies anti-CD11a, -CD11b, -CD11c, and -CD18. Normal skin frozen sections and epidermal sheets were investigated by immunohistology and immunofluorescence; suspended freshly isolated epidermal cells were processed using immunogold techniques, performed in both transmission and scanning electron microscopy, including double labeling procedures and semiquantitative analysis of the labeled cells. The results demonstrated the expression on the membrane of Langerhans cells of the CD11b, CD11c and CD18 antigens, thus indicating that at least both the H-Mac-1 (CD11b/CD18) and the gp150,95 (CD11c/CD18) members of the CD11/CD18 family are detectable on the cell surface of human resting Langerhans cells. Since both such moieties serve as adhesion molecules in (a) cell-cell interactions and in (b) leukocyte migration and localization, the present results suggest that H-Mac-1 and gp150,95 might display a key role (a) in promoting interactions between Langerhans cells and other cells, and (b) in guiding the migration and localization of Langerhans cells.

Adolescent↗
PubMed1989

The preS1 antigen of hepatitis B virus is highly immunogenic at the T cell level in man.

14 hepatitis B vaccine recipients who showed high titers of anti-hepatitis B surface antibodies in serum after booster immunization with a polyvalent hepatitis B surface antigen vaccine that contained trace amounts of hepatitis B virus (HBV) preS1 and preS2 envelope antigens were studied for their in vitro T cell response to these antigens. All 14 subjects displayed a significant proliferative T cell response to the S/p25 envelope region encoded polypeptide; 8 also responded to preS1, while only 1 showed a significant level of T cell proliferation to preS2. Limiting dilution analysis demonstrated that the frequency of preS-specific T cells in two of these vaccine recipients was higher than that of S/p25-specific T cells. T cell cloning was then performed and a total of 29 HBV envelope antigen-reactive CD4+ cloned lines were generated from two preS-responsive vaccines. 21 of these lines were S/p25 specific, 7 preS1 specific, and 1 preS2 specific. Taken together, all these results suggest that the preS1 antigen may function as a strong T cell immunogen in man.

Chromobox Protein Homolog 5↗
PubMed1989

Cabergoline: long-acting oral treatment of hyperprolactinemic disorders.

Cabergoline, a new orally active dopaminergic drug with an extremely long-lasting PRL-lowering effect, was given to 48 hyperprolactinemic women for 3-18 months (median, 8 months) at doses varying between 0.2-3 mg/week administered one to three times weekly. Serum PRL levels declined to normal in 41 women, 30 of whom received 0.2-1 mg cabergoline once weekly, 8 received 0.2-0.5 mg twice weekly, and 3 received 0.4-0.6 mg 3 times weekly. Five women had slightly supranormal serum PRL levels while receiving 0.3-0.6 mg once weekly, but the dose was not increased because the lower dose had produced the desired clinical benefit. Two women had 50% reductions in their serum PRL levels, but remained hyperprolactinemic while receiving 2-3 mg cabergoline weekly. Among 30 amenorrheic women, 28 had resumption of menses, the exceptions being 2 hypopituitary women, presumptive evidence of ovulation was available in 21. Marked tumor shrinkage occurred after 3-month treatment in 5 of the 6 women who had macroprolactinomas. Only 4 women had side-effects during the first weeks of treatment, and these vanished despite continued cabergoline administration at the same or reduced, but still effective, doses. In a short term, double blind study, cabergoline at 3 different schedules (0.4 mg twice weekly, 0.2 mg 4 times weekly, and 0.4 mg 3 times weekly for 3 weeks, followed by 0.4 mg twice weekly) or placebo was given to a total of 24 hyperprolactinemic women (6 in each subgroup) for 8 weeks, with weekly evaluation of serum PRL levels and side-effects. All 3 cabergoline schedules, but not placebo, induced significant reductions in serum PRL concentrations during the 8-week treatment period. Mild transient side-effects occurred in 7 drug-treated patients (nausea in 5; dizziness in 3). We conclude that cabergoline is effective treatment for hyperprolactinemia. Its efficacy, tolerability, and long duration of action may make it the drug of choice for patients with hyperprolactinemia.

Administration, Oral↗
PubMed1989

Diabetes and illness image: an analysis of diabetic early-adolescents' self-perception through the Draw-a-person test.

To study the self-projective representations expressed by diabetic children, aged between 10 and 15 yr., and to compare these with representations of a control group the Draw-a-person test associated with those for subsequent Draw-a-sick-person were administered to 23 children regularly checked by an Antidiabetic Centre. The diabetic subjects drew an image of "sick person" having projective elements with a regressive value and denoting a refuge in the past, together with depressive signs of retiring into themselves and of less consideration of the self. Also, the diabetic children seemed to be less prone to the cultural stereotype which requires a smiling and happy image of "the healthy person." At the same time there was also a transparent symbolic defense which allowed the diabetics to adapt variously and to move from their anxious state toward psychological recovery.

Adolescent↗
PubMed1989

[Clinical experience on the use of total parenteral nutrition in patients subjected to radical cystectomy intervention for infiltrating neoplasms of the bladder].

The Authors report their 7 year follow-up on the use of T.P.N. in 28 patients treated surgically for infiltrating cancer of the bladder. They consider the pathogenetic mechanisms that influence the organism's adaptation to surgical stress with particular reference to the multiple neuroendocrinal and biochemical interconnections. The procedures to define the nutritional/metabolic levels, of the patients undergoing operation are exposed. The T.P.N. is given according to the personal requirements of each patient and is a function of the "performance status", caloric need and to the presence of sepsis. Problems concerning the radical cistectomy such as: time of surgery, extention of exeresis, uroentheroanastomosis, metabolic variations, sepsis, etc., are evaluated. Considering the positive results obtained with this nutritional procedure, the Authors underline the importance of a systematic use of T.P.N. wich should be included, in their opinion, in a multidisciplinar treatment of advanced bladder neoplasms.

Female↗
PubMed1989

Further characterization of the "incipient lesion of chronic stationary type psoriasis vulgaris in exacerbation". The CD4-positive lymphocytes are the prominent cell population infiltrating the dermis.

In previous studies, others and we have demonstrated by immunohistological methods in light microscopy that the prominent cell population infiltrating the psoriatic lesional dermis is represented by CD4-positive cells, thus suggesting an implication of T4 lymphocytes in the development of psoriatic lesion. However, recent findings have indicated that not only T4 lymphocytes, but also macrophage-like cells, are CD4-positive. In the present study, therefore, a highly specific and sensitive 'in situ' gold-immunoelectronmicroscopy procedure developed by us was performed to identify ultrastructurally with precision the nature of the CD4-positive cells infiltrating the dermis of the incipient psoriatic lesion. Although a consistent proportion (28%) of slightly CD4-positive macrophage-like cells was detected, the strongly CD4-positive lymphocytes were the prominent cell subset (51%). The important role presumably played by such CD4-positive lymphocytes in the pathogenesis of the psoriatic lesion is discussed. Our gold-immunoelectronmicroscopy technique improved the study of psoriatic cell subpopulations in situ, since (a) in comparison with immunocytochemistry in light microscopy, it allowed us not only to recognize the ultrastructure of the labelled cells, but also to detect even small amounts of antigen on the cell surface; and (b) in comparison with the commonly used peroxidase immunoelectronmicroscopy techniques, it allowed us to quantitatively assess the expression of antigens (e.g. CD4) on different cell subpopulations (e.g. the low CD4 expression by macrophage-like cells versus the high CD4 expression by T4 lymphocytes).

CD4 Antigens↗
PubMed1988

Functional modulation of hepatitis B core antigen-specific T lymphocytes by an autoreactive T cell clone.

Hepatitis B core (HBc)Ag-specific T cells present in the peripheral blood of a patient with chronic active hepatitis B were expanded by co-cultivation for 7 days with rHBcAg. After cloning at 1 cell/well in the presence of PHA and IL-2, five HBcAg-specific CD4+ cloned lines were obtained. All five lines proliferated and produced IL-2, IFN-gamma, and TNF in a dose-dependent fashion in response to HBcAg, but not to HBV envelope Ag. The cloned lines and derivative clones were HLA class II (DR1) restricted. All T cell clones were able to induce anti-HBc production by autologous B cells in response to HBcAg (helper effect). The proliferative response and the helper effect of the HBcAg-specific T cell lines and clones were augmented by co-cultivation with an autologous, autoreactive (HLA-DQ1 specific) T cell clone, even in the absence of HBcAg, and the autoreactive T cells directly stimulated anti-HBc secretion by autologous B cells, presumably due to the release of Ag-nonspecific factors. These findings define a model immunoregulatory circuit the physiologic significance of which remains to be determined.

Adult↗