Showing papers by "University of Naples Federico II published in 1980"
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TL;DR: It is reported that Macrocortin derived from rat peritoneal leukocytes is an intracellular polypeptide whose release and synthesis are stimulated by steroids.
Abstract: Anti-inflammatory glucocorticoids inhibit prostaglandin (PG) biosynthesis by preventing arachidonic acid release from phospholipids rather than inhibiting the cyclooxygenase. As in other cells, this steroid action depends on receptor occupation and de novo protein/RNA biosynthesis. We have previously shown in guinea pig perfused lungs and rat peritoneal leukocytes that the effect of steroids in PG generation is mediated by an uncharacterized 'second messenger'. Now, we report that this factor (which we have named 'macrocortin') is an intracellular polypeptide whose release and synthesis are stimulated by steroids. Macrocortin derived from rat peritoneal leukocytes is very similar to that released from guinea pig lungs.
890 citations
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TL;DR: A class of mutations that increase the efficiency of a suppressor tRNA in translating a particular amber codon has been characterized due to a mutation resulting in a change in the mRNA that affects the nucleotide adjacent to the 3′ side of the UAG triplet.
Abstract: A class of mutations that increase the deficiency of a suppressor tRNA in translating a particular amber codon has been characterized. The increased efficiency is due to a mutation resulting in a change in the mRNA that affects the nucleotide adjacent to the 3' side of the UAG triplet. Thus the interaction of tRNA with mRNA is influenced by mRNA sequences outside the triplet codon.
262 citations
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TL;DR: A high-fibre, normal-carbohydrate diet improves blood glucose control and decreases the concentration of atherogenic lipoproteins in diabetic patients, independent of the amount of available carbohydrates in the diet.
169 citations
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TL;DR: The data indicate that long-term prednisone and/or azathioprine treatments favour the replication of hepatitis-B virus in patients with HBsAg-positive chronic active hepatitis.
132 citations
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TL;DR: The effect of nifedipine, a calcium antagonist, on carbohydrate metabolism and insulin secretion was evaluated in patients who required treatment with this drug and no effects were seen in the placebo (weight- and disease-matched) group.
Abstract: The effect of nifedipine, a calcium antagonist, on carbohydrate metabolism and insulin secretion was evaluated in patients who required treatment with this drug. 20 subjects underwent two oral glucose tolerance tests (100 g), one under basal conditions, and the other after ten days of treatment with nifedipine 30 mg/day by mouth, in three divided doses. 10 subjects had normal glucose tolerance; in them nifedipine administration reduced the insulin response to oral glucose in the first 60 min, but improved glucose tolerance. The other 10 subjects had impaired glucose tolerance and nifedipine treatment resulted in a further reduction both of insulin secretion and glucose tolerance. No such effects were seen in the placebo (weight- and disease-matched) group. The mechanism by which nifedipine influences carbohydrate metabolism and insulin secretion is discussed.
116 citations
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TL;DR: The influence of iv infusion of epinephrine, norepinephrine, and isoproterenol on glucose homeostasis in normal man was evaluated and glucose output was very transient and was not followed by a significant elevation of glucose uptake.
Abstract: This study was designed to evaluate the influence of iv infusion (50-1 ng kg-1 min) of epinephrine, norepinephrine, and isoproterenol on glucose homeostasis in normal man. Epinephrine infusion produced a 40–45 mg/dl increment of plasma glucose concentration which resulted from both a transient 85–90% rise in glucose production (P <0.005) and the failure of glucose uptake to increase consistently in response to hyperglycemia. Plasma insulin increased slightly (20–25‥), while plasma glucagon remained unchanged. Norepinephrine infusion produced a much smaller increase in glucose production (25–30‥) and plasma glucose (10–15 mg/dl) compared to epinephrine (P < 0.01 and P < 0.025, respectively). The increase in glucose output was very transient and was not followed by a significant elevation of glucose uptake. Plasma insulin and glucagon levels remained unchanged. The infusion of isoproterenol resulted in a 30–35% increase in glucose production (P < 0.025) which remained at levels significantly above baseline ...
105 citations
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TL;DR: Rat peritoneal leucocytes incubated with hydrocortisone release a factor which inhibits prostaglandin generation, which may be a protein or a polypeptide since its formation is blocked by cycloheximide, a known inhibitor of protein synthesis.
Abstract: Rat peritoneal luecocytes incubated with hydrocortisone (10 micrograms/ml) release a factor which inhibits prostaglandin generation. The steroid-induced inhibitor, which mediates the anti-phospholipase effect of antiinflammatory steroids, may be a protein or a polypeptide since its formation is blocked by cycloheximide, a known inhibitor of protein synthesis.
66 citations
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TL;DR: In this paper, the authors propose a new concept of integrity, distinct from the conventional integrity issues of first order data bases, which is defined as the need to consider such potential interactions.
Abstract: Although most commonly occurring default rules are normal when I viewed in isolation, they can interact with each other in ways that lead to the derivation of anomalous default assumptions. In order to deal with such anomalies it is necessary to re-represent these rules, in some cases by introducing non-normal defaults. The need to consider such potential interactions leads to a new concept of integrity, distinct from the conventional integrity issues of first order data bases. .br The non-normal default rules required to deal with default interactions all have a common pattern. Default theories conforming to this pattern are considerably more complex than normal default theories. For example, they need not have extensions, and they lack the property of semi-monotonicity. .br Current semantic network representations fail to reason correctly with defaults. However, when viewed as indexing schemes on logical formulae, networks can be seen to provide computationally feasible heuristics for the consistency checks required by default reasoning.
64 citations
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61 citations
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TL;DR: A rapid, sensitive and specific high-performance liquid chromatographic method for the simultaneous separation of natural adenosyl-sulphur compounds has been developed and can be applied to biological samples for the estimation of S-adenosyl)-3-methyl-thiopropylamine and for measurement of enzyme activities involving the above-mentioned compounds.
54 citations
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TL;DR: Brush border peptidases are probably involved in the digestion of gliadin, which is very rich in glutamic acid and proline residues; as these activities are lowered in the atrophic celiac mucosa, digestibility ofgliadin peptides might be reduced during active celiac disease.
Abstract: Summary: Peptidase activities have been investigated in the brush border of human proximal jejunum by using dipeptides and tripeptides and β-naphthylamides of glycyl-L-proline and amino acids as substrates. The activities hydrolyzing glycyl-L-leucine, L-phenylalanyl-L-alanine, and L-leucylglycylglycine in the brush border were found to be only 1.5, 15, and 16% of the total peptidase activities present in the intestinal mucosa, but the specific activities for the hydrolysis of these substrates appeared in the brush border to be as high as or higher than that of sucrase. The enzyme(s) hydrolyzing L-phenylalanyl-L-alanine in the brush border showed different properties from the enzyme(s) hydrolyzing the same substrate in the cytosol, the former being completely resistant to p-hydroxymercuribenzoate, partially resistant to heating, and inhibited by puromycin by about 50%. On the other hand, the enzymatic activities hydrolyzing the β-naphthylamides of glycyl-L-proline, L-leucine, and α-L-glutamic acid as well as N-carbobenzoxy-L-prolyl-L-alanine were shown to be almost totally localized in the brush border. All the peptidase and β-naphthylamidase activities studied were well solubilized by papain from the brush border membrane with the only exception being the activity hydrolyzing glycyl-L-leucine. By acrylamide gel electrophoresis, three enzymatic activities were clearly separated from each other as well as from the oligoaminopeptidase- (EC 3.4.11.2) splitting L-leucyl-β-naphthylamide: (1) the aminopeptidase A (EC 3.4.11.7) hydrolyzing α-L-glutamyl-β-naphthylamide; (2) the dipeptidylaminopeptidase IV (EC 3.4.14.-) liberating glycyl-L-proline from glycyl-L-prolyl-β-naphthylamide; and (3) a carboxypeptidase hydrolyzing N-carbobenzoxy-L-prolyl-L-alanine (EC 3.4.12.-). Brush border peptidases (oligoaminopeptidase, aminopeptidase A, dipeptidylaminopeptidase IV, and carboxypeptidase) and cytosol dipeptidase and tripeptidase activities were measured in intestinal biopsies of celiac patients utilizing specific substrates. These enzymatic activities were normal in eight children with celiac disease in histologic remission, with only aminopeptidase A being reduced to 70% of control values. On the contrary, in the atrophic mucosa of 12 children with active celiac disease, these were all significantly but not equally reduced. Speculation: The identification of the above-mentioned peptidases in the intestinal brush border demonstrates the importance of this sub-cellular organelle in the digestion of protein and peptides complementary to intraluminal and intracellular digestion. Brush border peptidases are probably involved in the digestion of gliadin, which is very rich in glutamic acid and proline residues; as these activities are lowered in the atrophic celiac mucosa, digestibility of gliadin peptides might be reduced during active celiac disease.
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TL;DR: This work was presented in part at the 12th Annual Contractor's Conference of the National Institutes of Arthritis, Metabolism and Digestive Diseases, Bethesda, USA, January 15, 1979 and the Congress of the International Society for Artificial Internal Organs at the symposium on CAPD, New York Hilton,New York, April 19, 1979.
Abstract: Nitrogen balance studies were performed in 8 patients undergoing CAPD. Patients were studied in a metabolic ward for 14 days while eating a diet providing 1.2 g/kg B.W. of proteins and supplying 166-188 KG/Kg. From these studies it is concluded that 1.2 g/Kg are a safe intake for patients on CAPD. Nevertheless it is strongly suggested that patients on CAPD should undergo a nitrogen balance study in order to ascertain whether such a diet is safe or should be modified for energy and/or protein supply.
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TL;DR: The myoglobin content in the hearts of several fishes is positively correlated with the ecological physiology of the species and in the tuna heart, where the highest myoglobin values are found, the logarithmic relationship betweenMyoglobin content and body weight is reported.
Abstract: The myoglobin content in the hearts of several fishes is positively correlated with the ecological physiology of the species. In the tuna heart, where the highest myoglobin values are found, the logarithmic relationship between myoglobin content and body weight is reported.
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TL;DR: Data indicate that, among the favourable changes in plasma lipoprotein pattern, an increase in HDL-C may be achieved after remarkable and stable weight loss in severe obesity.
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TL;DR: Precision, accuracy, and linearity of the method are highly satisfactory, and the method can be exploited to assay preformed estrogen-receptor complex by exchange with [3H]estradiol at low temperature.
Abstract: When 0.5 M sodium thiocyanate is added to uterine cytosol previously labeled with excess [3H]-17 beta-estradiol, no change can be detected in the steady-state cytosol concentration of [3H]estradiol-receptor complex for at least 20 h at 4 degrees C. However, the rate of exchange of bound estradiol in the presence of NaSCN was found to be substantially higher than that in the absence of the chaotropic salt. In the presence of NaSCN, the dissociation rate of the complex increases about 10-fold (K-1 SCN = 1.10 x 10(-2) min-1 vs. K-1 = 1.07 X 10 (-3)min-1) while the rate of association increases about 2-fold (K1 SCN = 1.2 X 10(7) min-1M-1 vs.K1= 7.4 X 10(6) min-1 M-1). The Kd changes 6.4-fold (Kd SCN = 9 X 10(-10) M vs. Kd = 1.4 x 10(-10 M) with no decrease in the number of binding sites as shown by Scatchard plots of saturation experiments. This effect of NaSCN can be exploited to assay preformed estrogen-receptor complex by exchange with [3H]estradiol at low temperature. When the sample containing preformed complex is incubated overnight (16 h) at 4 degrees C with excess [3H]estradiol in the presence of 0.5 M NaSCN, there is a quantitative exchange of nonlabeled for estradiol without loss of binding sites. Hormonal steroids other than estrogens do not interfere, and the exchange estradiol is bound with high affinity. Precision, accuracy, and linearity of the method are highly satisfactory.
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TL;DR: Hyperthyroidism is characterized by increased glucose turnover and hyperglucagonemia in the basal state, a reduced glucemic response to physiological infusions of epinephrine and glucagon, 3) a sustained response of glucose production to epine cortisol and glucagons, and 4) the lack of epinphrine-induced suppression of glucose clearance.
Abstract: To study the mechanism of altered glucose homeostasis in hyperthyroidism, the effects of a 2-h physiological infusion of epinephrine (0.05 μg%kg-min) or glucagon (3 ng%kgmin) on glucose kinetics and glucoregulatory hormones were determined in nine normal subjects and five untreated hyperthyroid patients. Under basal conditions, hyperthyroid patients exhibited increased glucose turnover (2.2 ± 0.09 us. 1.62 ±0.1 mg%kg-min in normals), a modest hyperglycemia, hyperglucagonemia, and normal levels of plasma insulin, cortisol, and GH. In normal subjects, epinephrine induced a sustained increase in plasma glucose (45 mg/dl), reflecting a transient 100% rise in glucose output, and a sustained 28% decrease in glucose clearance. In hyperthyroid patients, the rise in plasma glucose was significantly lower (22 mg/dl) due to a smaller but sustained increase in glucose output (45%) and the lack of a fall in glucose clearance. Plasma insulin rose to a peak 80% higher than baseline in hyperthyroid patients, whereas in n...
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TL;DR: It is concluded that a contractile system is present in Discoglossus eggs, and it is particularly developed in the dimple, probably a major compartment for the storage of unpolymerized tubulin.
Abstract: The distribution of actin, myosin, and tubulin has been investigated in coelomic oocytes, unfertilized and fertilized eggs of Discoglossus pictus utilizing: (1) immunofluorescence; (2) electron microscopy; (3) incubation with heavy meromyosin (HMM), and (4) SDS-polyacrylamide gel electrophoresis (PAGE). In coelomic oocytes, the germinative area (GA) has long, irregular microvilli containing microfilaments. In the rest of the oocyte, the microvilli are shallow. During the transit of the oocyte in the oviduct, a dimple forms by the invagination of the GA. A palisade of microfialment bundles is present in the finger-shaped microvilli of the dimple and extends for about 10 μm in the cytoplasm. In the rest of the egg, microvilli are absent and only random filaments appear in the cortex. Following HMM incubation, the dimple microfilaments are decorated with arrowheads pointing toward the bulk of the cytoplasm. SDS-PAGE of egg extracts shows bands co-migrating with actin (43K), pyruvate kinase (57K), and phosphorylase (94K). As result fertilization, the pattern of microfilament bundles in the dimple disappers in parallel with the dimple invergination itself. Generally, the entire oocyte cortex is positive to immunofluorescent staining with anti-actin, antimyosin, and antitubulin antibodies. However, the pattern of distribution and intensity of immunofluorescent staining changes for each antiserum, during different stages. It is concluded that a contractile system is present in Discoglossus eggs, and it is particularly developed in the dimple. The dimple is probably a major compartment for the storage of unpolymerized tubulin.
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TL;DR: This schematic classification includes precursors at several stages of differentiation, which sequentially evolve one into the other, in a process regulated via both long and short-range mediators?lo These include hormones such as erythropoietin and microenvironmental influences, respectively.
Abstract: Erythropoiesis has been a suitable tool for defining several aspects of the regulation of eukaryotic cell differentiation. The control of red blood cell formation involves a number of critical steps, which include proliferation of pluripotent hemopoietic stem cells, their commitment to erythopoiesis, the proliferation of committed precursor cells, and, finally, the expression of several biosynthetic and morphogenetic activities characteristic of terminally differentiated erythroid cells.',2 The in vitro development of clonal short-term cell cultures in semi-solid medium permitted identification of the precursors at different stages of the erythroid pathway. The most immature, pluripotent hemopoietic stem cell is the so-called CFU-S (spleen colony-forming unit),3 which is capable of both selfrenewal and differentiation to various precursors of the erythroid myelomonocytic, megakaryocytic and lymphoid lineage^.'.^ Two erythroid progenitors have been identified in mammals, the erythroid burst(BFU-E) and colony(CFU-E) forming-unit: the former represents an early progenitor, which differentiates into the late one, i.e. CFU-E.' This schematic classification includes precursors at several stages of differentiation, which sequentially evolve one into the other, in a process regulated via both longand short-range mediators?lo These include hormones such as erythropoietin and microenvironmental influences, respectively.
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TL;DR: All the above-mentioned symptoms constantly showed a shorter duration in the two groups treated with rifamycin SV compared to the group treated with other therapies, with differences as significant on statistical calculation as they were important on the level of a clinical evaluation of the disease's course.
Abstract: In a controlled clinical trial undertaken in ten Italian centres, rifamycin SV was compared to associations of various drugs such as erythromycin, aureomycin, multivitamin preparations, etc, in the treatment of herpes zoster. Up to now 144 patients, suffering from herpes zoster at different localizations, were divided into three groups and randomly given either rifamycin SV by intramuscular injection and topically, or rifamycin SV by injection only, or the routine treatment used at the particular centre in question. To evaluate the effectiveness of the treatments, the presence of subjective and objective symptoms was determined before treatment started and daily thereafter. The duration, in days, of the most important symptoms, such as erythema, vesicles, scabs and pain, was considered for this partial evaluation. All the above-mentioned symptoms constantly showed a shorter duration in the two groups treated with rifamycin SV compared to the group treated with other therapies, with differences as significant on statistical calculation as they were important on the level of a clinical evaluation of the disease's course.
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TL;DR: Gamma-globin chain synthesis has been evaluated in individual bursts and subcolonies that were generated by normal adult blood BFU-Es in methylcellulose cultures containing semipurified erythropoietin and then analyzed via either isoelectric focusing of globin chains or immunofluorescence techniques.
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TL;DR: The data collected demonstrate that peritoneal hyperalimentation is feasible and adequate for clinical purposes.
Abstract: Total parenteral nutrition was attempted by using the peritoneal route. In this way it was possible to convey to the patients all elemental nutrients used in hyperalimentation. Three patients were studied while treated for an episode of catabolic stress in the course of acute or chronic uremia. Adequacy of treatment was controlled by measuring urea generation rates, plasma concentrations of 3-methyl-histidine, glucose disappearance from dialysate and kinetics of lipid particles removal from plasma. The data collected demonstrate that peritoneal hyperalimentation is is feasible for adequate for clinical purposes.
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TL;DR: A careful analysis of the influence of ionic strength and pH on the reaction appears to be necessary in order to characterize a ribonuclease which shows activity towards double-stranded RNAs, and to allow a meaningful comparison between different enzymes capable of attacking these substrates.
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TL;DR: A role of endotoxin in the activation of humoral and cellular mechanisms involved in the host resistance to gram-negative bacterial infection is suggested.
Abstract: The effects of tolerance to Escherichia coli endotoxin on the phagocytic and bactericidal activity of the hepatic reticuloendothelial system against viable E. coli were examined using ex vivo perfused rat livers. Livers were isolated from control and endotoxin-tolerant rats and perfused with a medium containing 5% homologous serum from either control or tolerant rats. After the addition of the E. coli (2 × 107 cells per ml) to the perfusate, the hepatic clearance of the bacteria was followed for 30 min. The highest activation of the hepatic reticuloendothelial system was observed when serum from tolerant animals was added to the perfusate. Under these conditions phagocytosis was 47% (12% in controls), and 37 to 38% of the bacteria were killed (5% in controls). This activation was less when livers obtained from tolerant rats were perfused with serum from controls or with saline only. The data suggests that, during endotoxin tolerance, humoral factors play an important role in the activation of the hepatic reticulendothelial system, although a direct stimulation of Kupffer cells also occurs. The enhancement of phagocytosis by tolerant serum did not require the presence of homologous antibodies and involved the activation of the alternative complement pathway, since it was lost after removal of factor B activity. On the other hand, stimulation of intracellular killing required both complement and specific antibodies. The data suggest a role of endotoxin in the activation of humoral and cellular mechanisms involved in the host resistance to gram-negative bacterial infection.
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TL;DR: The concepts of composite mechanics have been used to design two materials for potential prosthesis of biomedical interest that attain specific physical properties and use polymers which show a high degree of biocompatibility.
Abstract: The concepts of composite mechanics have been used to design two materials for potential prosthesis of biomedical interest. They attain specific physical properties and use polymers which show a high degree of biocompatibility. The materials used were a poly (2-hydroxyethyl-methacrylate) as matrix and polyesther resin as reinforcing fibers. The mechanical performance of a uniaxially oriented composite has been adjusted to match the behaviour of a human tendon. A laminate composite has been modelled for use in plastic surgery.
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TL;DR: Macular cherry-red spot, myoclonus and progressive mental deterioration are described in a man of 16 years and abnormal urinary oligosaccharide excretion is due to absence of (2--6) neuraminidase which was not detected in fibroblast culture.
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TL;DR: Data supports the hypothesis that the spongy might play an important homeostatic role for protecting the compact layer—which is the major producer of the systolic force of the ventricle—against critical changes of proton and metabolite concentrations.
Abstract: 1. 1. In comparison with the compact, the spongy compartment shows higher accumulation of lactate and higher capacity both to carry out different stages of lactate oxidation and to incorporate lactate into the total cardiac lipids. In addition, lactate oxidation in the spongy is less depressed by acidosis. 2. 2. This data supports the hypothesis that the spongy might play an important homeostatic role for protecting the compact layer—which is the major producer of the systolic force of the ventricle—against critical changes of proton and metabolite concentrations.
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TL;DR: The present data show that experimentally-controlled environmental variables (light and temperature) can alter circulating androgen levels in the male green frog, Rana esculenta, treated in different phases of the testicular cycle.
Abstract: The present data show that experimentally-controlled environmental variables (light and temperature) can alter circulating androgen levels in the male green frog,Rana esculenta, treated in different phases of the testicular cycle.
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TL;DR: A new model of focal cerebral ischemia following a selective occlusion of the middle cerebral artery in rats is reported, without additional insults of hypoxia, hypotension and handling of carotid and vertebral arteries, as required in previously described models.
Abstract: The authors report a new model of focal cerebral ischemia following a selective occlusion of the middle cerebral artery in rats, without additional insults of hypoxia, hypotension and handling of carotid and vertebral arteries, as required in previously described models.
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TL;DR: It is postulated that in fetal liver (and also in adult marrow) the synthesis of γ-chain is linked to an early differentiation stage of erythroblasts, while β-globin synthesis is largely activated at a more advanced maturation stage.
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TL;DR: In this article, the angular distribution of protons emitted from the reaction was measured in the energy range from 9 to 14 MeV and the value of the strength of the residual two-body interaction was derived.
Abstract: Excitation functions and angular distributions of protons emitted from the reaction $^{27}\mathrm{Al}$($^{3}\mathrm{He}$,$p$)$^{28}\mathrm{Si}$ have been measured in the energy range from 9 to 14 MeV. Some of the excitation functions show the presence of fluctuations that can be attributed to the statistical multistep compound emission. This effect explains also the shape and absolute value of the emitted proton spectrum measured at 13 MeV incident $^{3}\mathrm{He}$ beam. This comparison yields the value of the strength of the residual two-body interaction.