Showing papers by "University of Perugia published in 1979"

Natural Killer Cells: Characteristics and Regulation of Activity

Abstract: Recently there has been increasing recognition of natural cell-mediated cytotoxicity as a potentially important antitumor effector mechanism in addition to that of specifically immune T cells and of activated macrophages. Although natural cellular cytotoxicity was first recognized only a few years ago (Herberman et al. 1973,1974, McCoy et al. 1973b, Oldham et al. 1973, Rosenberg et al. 1972,1974), there has already been extensive research in many laboratories on the nature of the effector cells, the possible mechanisms of cytotoxicity, the factors regulating the levels of reactivity, and the relevance of natural immunity to in vivo resistance against tumor growth and immune surveillance. A principal component of natural cell-mediated cytotoxicity in rodents and man has been found to be a particular subpopulation of lymphocytes which have been termed natural killer (NK) cells. We have recently reviewed in detail much of the available information on NK cells (Herberman & Holden 1978). In this paper we will only summarize our views on the characteristics of NK cells and focus on a few issues of current interest in our laboratory.

Rapid In Vivo Assay of Mouse Natural Killer Cell Activity

Abstract: A rapid elimination of tumor cells from some organs was detected in mice following iv injection of tumor cells labeld in vitro with [125I]5-iodo-2'-deoxyuridine. Recovery of radioactivity in different organs (spleen, liver, and lungs) was reduced in mice with high natural killer (NK) cell reactivity in their spleens, as measured in vitro by concomitant short-term 51Cr release assay. Considerable parallelism between in vitro and in vivo reactivities against two mouse lymphomas and a human myeloid cell line was found in mice of different strains and ages. Similarly, various immunophamacologic treatments had comparable effects on in vitro and in vivo reactivities. These findings are consistent with the hypothesis that rapid cytolysis of tumor cells occurred in vivo and that NK cells played a major role in their elimination.

The effect of the epidermal growth factor (EGF) on the corneal epithelium in humans

Abstract: Epidermal growth factor (EGF) is a polypeptide hormone present in mammalian organs. In vivo, it shortens the time course of the corneal reepithelialization by stimulating a marked cell proliferation of the corneal epithelium. A further direct effect in vivo has been confirmed on human corneal epithelium and epidermis in culture.

Acute and chronic effects of nifedipine on plasma renin activity and plasma adrenaline and noradrenaline in controls and hypertensive patients.

Abstract: 1 Nifedipine, a calcium antagonist drug, was given sublingually (10 mg) to seven normal subjects and 19 patients with essential hypertension In addition, 12 of the hypertensive subjects then received nifedipine (10 mg thrice daily) for 3 weeks 2 Sublingual administration of nifedipine in hypertensive patients induced a prompt and sustained reduction of blood pressure, without a significant increase of heart rate; in normotensive subjects blood pressure did not change, and heart rate was significantly increased After chronic treatment, blood pressure remained reduced and heart rate did not rise 3 Plasma catecholamines and plasma renin activity increased significantly in normotensive subjects after acute administration 4 After both acute and chronic administration, only plasma noradrenaline was significantly increased in hypertensive patients; in long-term treatment, it was increased in both the lying and standing positions 5 Nifedipine is an active antihypertensive drug, which may induce some degree of sympathetic activation

Correlation Between Natural and Antibody-Dependent Cell-Mediated Cytotoxicity Against Tumor Targets in the Mouse. II. Characterization of the Effector Cells

Abstract: Direct comparison of the effector cells mediating natural killer (NK) activity against mouse tumor cells and antibody-dependent cell-mediated cytotoxicity (ADCC) against mouse tumor target cells coated with alloantisera indicated that NK cells and K-cells (effector cells mediating ADCC) may belong to the same subpopulation of lymphocytes, but they have a different mechanism of killing. Effector cells mediating NK activity and ADCC were nonadherent, nonphagocytic Fc receptor-bearing cells that sediment at 3.5-4.5 mm/hour. Treatment with anti-Thy 1.2 serum in the absence of complement resulted in an increase of NK activity, whereas this treatment caused a substantial loss in ADCC. Both NK activity and ADCC were equally sensitive to the in vivo or in vitro effects of X-irridiation. In vivo inoculations of high doses of hydrocortisone resulted in a reduction of NK activity, but ADCC was not affected. NK cells were trypsin-sensitive, with a profound decrease in the cytolytic activity being observed in a 4-hour 51Cr release assay. The activity, however, could be recovered after overnight incubation at 37 degrees C. Trypsin treatment did not inhibit ADCC as measured by the 18-hour assay.

Activation of mouse macrophages by pyran copolymer and role in augmentation of natural killer activity

Abstract: Inoculation of mice with pyran copolymer resulted in activation of natural killer (NK) cells as well as macrophages. Conditions optimal for the boosting of NK activity seemed to differ from those optimal for macrophage activation as assessed by cytostasis of tumor target cells. Peak levels of macrophage cytostatic reactivity were found at about 7 days after drug injection and were only achieved by the highest doses of pyran tested. Macrophage activation was consistently higher in the peritoneal cavity than in the spleen, regardless of route of administration, in contrast to the failure of i.v. pyran to induce high NK reactivity in peritoneal exudate cells. At 2-3 days after pyran treatment of older mice, NK augmentation reached peak levels, but only minimal macrophage activation was found. Despite these differences, macrophages played a role in regulating NK activity in pyran-treated mice. Functional macrophages appeared to be required for augmentation of NK activity by pyran, since boosting was impaired by prior in vivo inoculation of silica. Macrophages also appeared able to inhibit NK activity. In younger mice that exhibited high spontaneous levels of NK activity, pyran treatment produced a substantial reduction in NK activity to levels below those of untreated mice. This depression coincided with the time of peak levels of macrophage cytostasis. Furthermore, removal of adherent cells from the spleen cells of these pyran-treated mice resulted in levels of NK activity almost as high as those of untreated mice. The possibility that the depression of NK activity in young mice by pyran copolymer is due to suppressor cells is discussed.

Augmentation of natural killer activity by pyran copolymer in mice.

Abstract: Treatment of older mice with pyran copolymer, a known interferon-inducer, was found to result in a rapid boosting of cell-mediated cytolytic activity against YAC-1 tumor target cells. The effector cells were characterized as being non-adherent and were presumed to be natural killer (NK) cells. Augmentation occurred in various lymphoid organs and was detectable 2-3 days after drug treatment. Differences in the levels of boosted activity among the lymphoid organs resulted when the route of administration was varied. The degree of augmentation was largely independent of the dose of pyran, but did vary among different strains of mice. Augmentation, moreover, was followed by a rapid decline by 5-7 days.

Synthesis of phosphatidylcholine and phosphatidylethanolamine at different ages in the rat brain in vitro

Abstract: The de novo synthesis of choline and ethanolamine phosphoglycerides in brain microsomes from 18 month-old male rats was investigated in vitro by using labeled cytidine-5′-diphosphate choline and cytidine-5′-diphosphate ethanolamine as lipid precursors. The rate of synthesis of the two phospholipid classes was found to be noticeably decreased, as compared to that of adult animals. The addition of exogenous diacyl glycerols to microsomes from ageing rat brain brings the rate of synthesis nearly to the adult levels. The synthesis of choline and ethanolamine phosphoglycerides is not affected in the liver microsomes of ageing rats. The molar distribution of fatty acids in brain microsomal diacyl glycerols of ageing rats is noticeably different from that of adult animals. The content of monoenoic and dienoic species is increased, whereas that of the tetraenoic species is decreased. Base exchange reaction for choline and ethanolamine incorporation into respective phospholipids is not affected in the brain microsomes of the aged rats.

Interstitial deletion 13q syndromes: a report on two unrelated patients.

Abstract: A partial monosomy 13 by interstitial deletion was found in the complement of two patients with mental retardation and mild dysmorphic features. Neither of the patients had a retinoblastoma, even though the second patient had a 13q14 deletion. The karyotype-phenotype correlation in the two patients suggests the need to reconsider the clinical profile of these rare chromosomal syndromes in a large series of subjects.

Increased immunogenicity of L1210 leukemia following short-term exposure to 5(3,3′-dimethyl-1-triazeno)-imidazole-4-carboxamide (DTIC) in vivo or in vitro

Abstract: Short-term exposure of L1210 Ha leukemia to DTIC in vivo or in vitro resulted in the generation of leukemic cells that were moderately immunogenic for histocompatible (BALB/C × DBA/2)F1 (CD2F1) mice. In vivo treatment was carried out in the peritoneal cavity of CD2F1 host for 8–36 h. In vitro experiments were performed in glass vessels, in which tumor cells were incubated with DTIC for 2 h at 37° C. The in vitro generation of immunogenic leukemia was conditioned by the presence of mouse liver microsomes capable of producing metabolic transformation of DTIC. It follows that the increase of tumor cell immunogenicity produced in vitro and possibly in vivo by DTIC is due to (a) metabolic product (s) that has (have) not yet been identified. Somatic mutation, selection, viral activation, or other mechanisms could be responsible for the DTIC effect. The present studies suggest that similar in vivo or in vitro techniques could be used to obtain human tumor cells with higher immunogenicity.

The synthesis of choline phosphoglycerides in the giant fibre system of the squid.

Abstract: — The mechanisms and pathways of synthesis of phosphatidylcholine in the giant fibre system of the squid (Loligo vulgaris) have been examined by incubating the stellate ganglion-nerve preparation or its separated compartments in an artificial bathing solution with labelled choline. Other experiments were done by dissecting the whole stellate ganglion into axoplasm, axon sheath, giant fibre lobe, small fibres and ganglion residue, after incubation. The initial rate of choline incorporation into choline phosphoglycerides was severalfold higher in the lobe than in the axon. Higher lipid radioactivity was recovered in the axon sheath as compared to the axoplasm, and in the small fibres as compared to the ganglion residue which contains its cell bodies. The production of phosphorylcholine and CDP-choline in the intact ganglion-nerve preparation during incubation with choline points to the occurrence of the net synthesis pathway for phosphatidylcholine in this material. Base-exchange activity was also observed in the axon and giant fibre lobe preparations in vitro, but no indication can yet be given whether it also takes place in intact preparations. Electrical stimulation and‘depolarizing’conditions enhance choline phosphorylation in the squid axon and lobe, but decrease phosphatidylcholine labelling.

Development of grapeseed protein

Abstract: The potential for grapeseed oil and protein in regions where grape production is significant is discussed. Extraction and concentration procedures which improve the nutritional value of grapeseed protein and problems related to protein digestibility are presented.

The constitutional fragility of chromosome 12 in a case of 46,XX,var(12)(qh′,RHG,GAG,CBG)

Abstract: The constitutional fragility of chromosome no. 12 in a female infant with unspecific clinical signs is described. RHG, GAG, and CBG methods were used to localize the fragile point. The breaks seem to be in 12q1.3, and always within an R band. A possible correlation between the phenotypic modifications and the chromosome variant is discussed.

Transfer function-noise model applied to flow forecasting / Modèle Box-Jenkins pour la prévision des débits des cours d'eau

Abstract: The combined transfer function-noise model investigated by Box and Jenkins has been used to identify a model and estimate parameters for the simulation and forecasting of streamflow. The model reliability was tested with hourly storm data recorded in three basins of different size (7.6, 5.3 and 841 km2). The model proved to be satisfactory in short term (few hours) forecasting. As real time streamflow forecasting may be of practical importance, details are given about program dimensions, data requirements and job execution costs.

Trisomy 6p22 leads to 6pter due to familial t(6;13)(p22;q34 or 33) translocation.

Abstract: A newborn with a 46,XY, der(13),t(6;13)(p22;q34 or 33)pat karyotype, trisomic for the 6p22→6pter segment and, perhaps, monosomic for the 13q telomere, is reported. The balanced translocation is familial and was also encountered in the sister and paternal grandmother. The infant's phenotype was similar to that described in seven previously reported cases of partial trisomy 6p and further supports a partial trisomy 6p syndrome as proposed by Breuning et al.