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Boer M, Cosma A, Twenge JM, Inchley J, Jeriček Klanšček H, Stevens GWJM. National-Level Schoolwork Pressure, Family Structure, Internet Use, and Obesity as Drivers of Time Trends in Adolescent Psychological Complaints Between 2002 and 2018. J Youth Adolesc 2023:10.1007/s10964-023-01800-y. [PMID: 37349663 PMCID: PMC10371956 DOI: 10.1007/s10964-023-01800-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 05/25/2023] [Indexed: 06/24/2023]
Abstract
Little is known about societal processes that contribute to changes in adolescent mental health problems. This study aims to fill this gap using data from the Health Behavior in School-aged Children study between 2002 and 2018 (ncountries = 43, nindividuals = 680,269, Mage = 14.52 (SD = 1.06), 51.04% female), supplemented with other international data. National-level psychological complaints increased more strongly among girls than boys. National-level schoolwork pressure, single-parent households, time spent on internet, and obesity were generally rising. In both boys' and girls' samples, increases in national-level schoolwork pressure, obesity, and time spent on internet use were independently associated with increases national-level psychological complaints. However, national-level obesity and psychological complaints were more strongly related among girls than boys. Results highlight the potential impact of societal-level processes on adolescent mental health problems.
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Affiliation(s)
- M Boer
- Department of Interdisciplinary Social Science, Utrecht University, Utrecht, the Netherlands.
| | - A Cosma
- Department of Sociology, Trinity College Dublin, Dublin, Ireland
| | - J M Twenge
- Department of Psychology, San Diego State University, San Diego, CA, USA
| | - J Inchley
- MRC/CSO Social and Public Health Sciences Unit, University of Glasgow, Glasgow, UK
| | | | - G W J M Stevens
- Department of Interdisciplinary Social Science, Utrecht University, Utrecht, the Netherlands
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Cosma A, Balazsi R, Baban A. BULLYING NAS CRIANÇAS ROMENAS: O PAPEL DO ABUSO DE SUBSTÂNCIAS. Psic , Saúde & Doença 2015. [DOI: 10.15309/15psd160106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Bruel T, Demoulins T, Kreutz C, Dutrieux J, Cosma A, Corneau A, Dupuy S, Delache B, Torres C, Cheynier R, Bosquet N, Grand RL, Vaslin B. P121 Impact of the dynamics of plasmacytoid dendritic cells in the regulation of alpha interferons during primary infection of cynomolgus macaques by simian immunodeficiency virus. Cytokine 2012. [DOI: 10.1016/j.cyto.2012.06.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Hamimi C, Bruel T, Dereuddre-Bosquet N, Cosma A, Shin S, Corneau A, Versmisse P, Torres C, Delache B, Even S, Guenounou S, Targat B, Malleret B, Karlsson I, Barré-Sinoussi F, Le-Grand R, Pancino G, Saez-Cirion A, Vaslin B. Loss and regain of SIV control upon CD8+ cell depletion in vivo in SIV-controller macaques is not associated with efficient SIV specific CD8+ T-cells. Retrovirology 2012. [PMCID: PMC3441304 DOI: 10.1186/1742-4690-9-s2-p287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Coracina A, Gaiani S, Cosma A, Pellizzari P, Pizzi C, de Kreutzenberg S, Cecchet D, Sacerdoti D, Tessari P. No association between the degree of liver steatosis and early signs of vasculopathy in T2DM. Nutr Metab Cardiovasc Dis 2012; 22:e11-e12. [PMID: 22397876 DOI: 10.1016/j.numecd.2011.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Accepted: 11/28/2011] [Indexed: 12/20/2022]
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Kutscher S, Allgayer S, Dembek CJ, Bogner JR, Protzer U, Goebel FD, Erfle V, Cosma A. MVA-nef induces HIV-1-specific polyfunctional and proliferative T-cell responses revealed by the combination of short- and long-term immune assays. Gene Ther 2010; 17:1372-83. [DOI: 10.1038/gt.2010.90] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Tessari P, Cosma A, Vettore M, Millioni R, Puricelli L, Cogo P, Cecchet D, Carnielli V, Kiwanuka E. Fibrinogen kinetics and protein turnover in obese non-diabetic males: effects of insulin. Diabetes Metab Res Rev 2010; 26:50-8. [PMID: 19943326 DOI: 10.1002/dmrr.1055] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Although hyperfibrinogenemia and insulin resistance are common in obesity and diabetes mellitus, the impact of obesity per se on fibrinogen turnover and the insulin effects on fibrinogen and protein kinetics is unknown. METHODS We measured fibrinogen and albumin fractional (FSR) and absolute (ASR) synthesis rates, as well as protein turnover, in non-diabetic, obese and in control male subjects both before and following an euglycemic, euaminoacidemic, hyperinsulinemic clamp, using L-[(2)H(3)]-Leucine isotope infusion. RESULTS In the obese, basal fibrinogen concentrations was approximately 25% greater (p < 0.035), and fibrinogen pool approximately 45% greater (p < 0.005), than in controls. Both FSR and ASR of fibrinogen were similar to control values. With hyperinsulinemia, although fibrinogen FSR and ASR were not significantly modified with respect to baseline in either group, fibrinogen ASR resulted to be approximately 50% greater in the obese than in controls (p < 0.015). Hyperinsulinemia equally stimulated albumin synthesis and suppressed leucine appearance from endogenous proteolysis in both groups. Amino acid clearance was also similar. In the obese, the insulin-mediated glucose disposal was approximately 50% lower (p < 0.03) than in controls, and it was inversely correlated with fibrinogen ASR during the clamp in both groups (r = - 0.58). CONCLUSIONS In obese, non-diabetic males, post absorptive fibrinogen production is normal. Whole-body amino acid disposal, basal and insulin-responsive protein degradation, and albumin synthesis are also normal. However, the greater fibrinogen ASR in the obese with hyperinsulinemia, and the inverse relationship between insulin sensitivity and clamp fibrinogen production, suggest a role for hyperinsulinemia and/or insulin resistance on fibrinogen production in obesity.
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Affiliation(s)
- P Tessari
- Department of Clinical and Experimental Medicine, Chair of Metabolism, Policlinico Universitario, via Giustiniani 2, Padua, Italy.
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Kutscher S, Allgayer S, Dembek CJ, Bogner JR, Goebel FD, Erfle V, Cosma A. P18-04. MVA-nef vaccination induces specific T-cell responses exerting functions associated with non-progressive disease in HIV-1 infected individuals. Retrovirology 2009. [PMCID: PMC2767819 DOI: 10.1186/1742-4690-6-s3-p313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Tessari P, Coracina A, Cosma A, Tiengo A. Hepatic lipid metabolism and non-alcoholic fatty liver disease. Nutr Metab Cardiovasc Dis 2009; 19:291-302. [PMID: 19359149 DOI: 10.1016/j.numecd.2008.12.015] [Citation(s) in RCA: 218] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 12/10/2008] [Accepted: 12/29/2008] [Indexed: 12/16/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is an increasingly recognized pathology with a high prevalence and a possible evolution to its inflammatory counterpart (non-alcoholic steatohepatitis, or NASH). The pathophysiology of NAFLD and NASH has many links with the metabolic syndrome, sharing a causative factor in insulin resistance. According to a two-hit hypothesis, increased intrahepatic triglyceride accumulation (due to increased synthesis, decreased export, or both) is followed by a second step (or "hit"), which may lead to NASH. The latter likely involves oxidative stress, cytochrome P450 activation, lipid peroxidation, increased inflammatory cytokine production, activation of hepatic stellate cells and apoptosis. However, both "hits" may be caused by the same factors. The aim of this article is to overview the biochemical steps of fat regulation in the liver and the alterations occurring in the pathogenesis of NAFLD and NASH.
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Affiliation(s)
- P Tessari
- Department of Clinical and Experimental Medicine, Chair of Metabolism, University of Padua, Italy.
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Russo V, Scott IU, Stella A, Balducci F, Cosma A, Barone A, Delle Noci N. Nonpenetrating deep sclerectomy with reticulated hyaluronic acid implant versus punch trabeculectomy: a prospective clinical trial. Eur J Ophthalmol 2008; 18:751-7. [PMID: 18850554 DOI: 10.1177/112067210801800515] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To compare the intraocular pressure (IOP)-lowering effect and complication rate of nonpenetrating deep sclerectomy (NPDS) with reticulated hyaluronic acid (SK-GEL) scleral implant versus traditional punch trabeculectomy (PT) in the management of primary open angle glaucoma (POAG). METHODS Prospective, randomized comparative study including 93 patients with uncontrolled POAG. Group 1 (43 eyes) underwent NPDS with SK-GEL scleral implant; Group 2 (50 eyes) underwent PT. Mitomycin C (0.2 mg/mL) was applied intraoperatively in both techniques. Study follow-up evaluations were conducted at 36 and 48 months. Complete success indicated the achievement of the target IOP without antiglaucoma medications, while qualified success indicated the same goal with medications. These categories were assessed at two target IOP levels, <21 mmHg and <18 mmHg. RESULTS At 36 months for complete and qualified success with a <21 and <18 mmHg target IOP, no significant differences were noted between the two groups. At 48 months postprocedure when a <21 mmHg IOP target was considered, the rate of eyes that achieved complete success was 51.1% in the NPDS group versus 72% in the PT group (p<0.05). As for the <18 mmHg IOP target, the rate of eyes that achieved complete success was 32.5% in the NPDS group versus 44% in the PT group (p<0.05). Complications occurred significantly more frequently after PT than after NPDS. CONCLUSIONS The IOP-lowering effects of the two procedures were comparable at 36 months. At 48 months PT showed a significantly higher rate of complete success compared with NPDS. Complications were more frequent after PT than after NPDS.
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Affiliation(s)
- V Russo
- Institute of Ophthalmology, University of Foggia, Foggia - Italy.
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Pârvu AE, Negrean V, Pleşca-Manea L, Cosma A, Drăghici A, Uifălean A, Moldovan R. Nitric oxide in patients with chronic liver diseases. Rom J Gastroenterol 2005; 14:225-30. [PMID: 16200231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
AIM Chronic liver disease (CLD) may be accompanied by portal hypertension (PHT). Nitric oxide (NO) system disturbances seem to play a key role in the pathogenesis of CLD and PHT. In this study we aim to assess if in chronic active hepatitis (CAH) and cirrhosis (CIR), CLD severity and etiology can be correlated with the serum level of NO metabolites. METHOD The study was performed on 92 patients divided according to the diagnosis and Child-Pugh class, and a control group of 10 healthy volunteers. Serum nitrite/nitrate and citrulline levels were measured in order to evaluate NO synthesis. RESULTS AND CONCLUSION In CLD patients there was an increased NO production. In CIR NO synthesis increased more than in CAH. In CIR patients only nitrite/nitrate concentrations were correlated with citrulline levels. NO metabolites from CAH and CIR patients varied according to disease etiology, namely NO synthesis was more important in HCV-CLD than in alcoholic-CLD and HBV-CLD. In CIR patients, NO metabolites level increased with disease severity.
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Affiliation(s)
- Alina Elena Pârvu
- Department of Pathophysiology, University of Medicine and Pharmacy, 400020 Cluj-Napoca, Romania.
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Lopalco L, Pastori C, Cosma A, Burastero SE, Capiluppi B, Boeri E, Beretta A, Lazzarin A, Siccardi AG. Anti-cell antibodies in exposed seronegative individuals with HIV type 1-neutralizing activity. AIDS Res Hum Retroviruses 2000; 16:109-15. [PMID: 10659050 DOI: 10.1089/088922200309458] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Despite repeated exposures to HIV-1, some individuals remain seronegative. This study reports that sera from a fraction of exposed seronegative (ESN) subjects showed HIV-neutralizing activity; 5 of 17 ESN sera and none of 17 controls neutralized two different HIV-1 primary isolates (range of neutralizing titers: 1/20 to 1/60). The neutralizing activity was associated with the IgG fraction of 4 of 4 neutralizing ESN sera. Moreover, in 11 of 17 and 9 of 17 ESN sera (but none of the control sera) we found antibodies against HLA class I and CD4, respectively. One of the ESN sera (EU22) neutralized efficiently the primary virus derived from the seropositive partner and showed a good broadly cross-reactive neutralization. Immunoadsorption of two IgG fractions from EU19 and EU22 on peripheral blood mononuclear cells (PBMC) removed virus-neutralizing antibodies. The correlations between the ESN status and neutralizing activity (p<0.05), anti-HLA antibodies (p<0.0002), and anti-CD4 antibodies (p<0.001) were statistically significant. However, there was no statistically significant correlation between neutralizing activity and either anti-HLA or anti-CD4 antibodies. It can therefore be said that exposure to HIV-1 without seroconversion is, in some individuals, associated with HIV-neutralizing antibodies (not directed against viral antigens) and/or with anti-cell autoantibodies, which are possibly specific for cellular antigens involved in the infection/entry process.
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Affiliation(s)
- L Lopalco
- DIBIT and Infectious Diseases Clinic, San Raffaele Scientific Institute, Milan, Italy.
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Cosma A, Blanc D, Braun J, Quillent C, Barassi C, Moog C, Klasen S, Spire B, Scarlatti G, Pesenti E, Siccardi AG, Beretta A. Enhanced HIV infectivity and changes in GP120 conformation associated with viral incorporation of human leucocyte antigen class I molecules. AIDS 1999; 13:2033-42. [PMID: 10546855 DOI: 10.1097/00002030-199910220-00005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Assembly of human immunodeficiency virus type 1 (HIV-1) occurs at the level of the plasma membrane of the host cell. During this process HIV incorporates significant quantities of cell surface-derived molecules into its lipid bilayer including human leucocyte antigen (HLA) class I and II, intercellular adhesion molecule-1 and lymphocyte function antigen-1. Several studies indicate that virion-bound host-cell-derived molecules are functional and affect the biological properties of HIV-1. Virion-associated HLA class II and intercellular adhesion molecule-1 enhance the infectivity of T-cell line-adapted (TCLA) viruses. No role for virion-associated HLA class I molecules has yet been identified. OBJECTIVE To investigate the role of HLA class I molecules in HIV replication and infectivity. METHODS HLA class I negative human cells lines transfected with the HLA Cw4 gene were infected with different TCLA viruses as well as primary X4 isolates. The infectivity of HLA Cw4 positive and negative viruses was determined on indicator cell lines and on phytohaemagglutinin-activated peripheral blood mononuclear cells. An entry polymerase chain reaction assay was used to determine differences in entry-competence of Cw4 positive and negative viruses. The expression of selected gp120 epitopes on native Env molecules derived from Cw4 positive and negative viruses was determined by a monoclonal antibody-based enzyme-linked immunosorbent assay. Immunoprecipitation experiments were performed to investigate the presence of gp120/HLA Cw4 complexes. Neutralization assays determined the differences in susceptibility to neutralization between HLA Cw4 negative and positive viruses. RESULTS AND CONCLUSIONS The infectivity of primary HIV-1 X4 isolates and of TCLA viruses is increased upon viral incorporation of HLA Cw4 molecules. This effect is associated with changes in viral envelope proteins conformation including an enhanced expression of the V3 loop of gp120, and of epitopes that are exposed upon CD4 binding. The gp120 conformational changes are consistent with the formation of a multimolecular complex between HLA class I and gp120/160. HLA Cw4 incorporation is also associated to a lower susceptibility to antibody neutralization. These findings have important implications for understanding the immune response to cryptic and conformational epitopes of the viral envelope.
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Affiliation(s)
- A Cosma
- Centre Intégré de Recherches Biocliniques sur le SIDA, Paris, France
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Mazzoli S, Lopalco L, Salvi A, Trabattoni D, Lo Caputo S, Semplici F, Biasin M, Bl C, Cosma A, Pastori C, Meacci F, Mazzotta F, Villa ML, Siccardi AG, Clerici M. Human immunodeficiency virus (HIV)-specific IgA and HIV neutralizing activity in the serum of exposed seronegative partners of HIV-seropositive persons. J Infect Dis 1999; 180:871-5. [PMID: 10438383 DOI: 10.1086/314934] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The presence and activity of human immunodeficiency virus (HIV)-specific antibodies were analyzed in the sera of 15 sexually exposed seronegative persons who had systemic HIV-specific cell-mediated immunity and IgA-mediated mucosal immunity and in their HIV-infected partners. The HIV-positive subjects had HIV-specific serum IgG and IgA; the seronegative persons had HIV-specific serum IgA in the absence of IgG. Testing of the seronegative persons 1 year after the interruption of at-risk sex showed that no IgG seroconversion had occurred and that HIV-specific IgA serum concentrations had declined. Serum from the HIV-exposed seronegative persons was analyzed for the ability to neutralize primary HIV-1 isolates. Neutralizing activity was detected in 5 of 15 sera and in 2 cases was retained by serum-purified IgA. Thus, the immunologic picture for resistance to HIV infection should include HIV-specific cell-mediated immunity as well as HIV-specific IgA-mediated mucosal and systemic immunity.
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Affiliation(s)
- S Mazzoli
- Centro Unitá Operativa di Malattie Sessualmente Trasmesse, Malattie Infettive, Ospedale S. M. Annunziata, Florence, Italy.
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Pazè C, Zecchina A, Spera S, Cosma A, Merlo E, Spanò G, Girotti G. Comparative IR and 1H-MAS NMR study of adsorption of CD3CN on zeolite H-β: evidence of the presence of two families of bridged Brnsted sites. Phys Chem Chem Phys 1999. [DOI: 10.1039/a902621e] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Biotinylation has become a popular alternative to radioiodination for labeling cell surface proteins, whereas labeling of the total cellular protein pool is usually achieved metabolically with [35S]methionine and [35S]cysteine. In this paper we describe a new technique in which total cellular lysate proteins that have been affinity bound to a solid phase are labeled efficiently with biotin. This labeling technique is preferable to direct biotinylation of cell lysate since the unreacted biotin can be readily removed from the sample by washing. The affinity step permits preselection of the molecules to be labeled, thereby decreasing the potential for nonspecific binding during subsequent immunoprecipitation. We applied this affinity biotinylation method to a human cellular lysate in order to preselect the total glycoprotein pool for subsequent immunoprecipitation of HLA class I. Following immunoprecipitation, SDS-PAGE, and Western blot, the biotinylated protein could be readily revealed by enhanced chemiluminescence. The results were comparable to those obtained by radiometabolic labeling and Western blot using a monoclonal antibody probe. Overall, the affinity biotinylation method is faster and more practical than conventional radiolabeling, without any loss in sensitivity.
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Vanoni MA, Cosma A, Mazzeo D, Mattevi A, Todone F, Curti B. Limited proteolysis and X-ray crystallography reveal the origin of substrate specificity and of the rate-limiting product release during oxidation of D-amino acids catalyzed by mammalian D-amino acid oxidase. Biochemistry 1997; 36:5624-32. [PMID: 9153402 DOI: 10.1021/bi963023s] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Limited proteolysis of D-amino acid oxidase holoenzyme with trypsin cleaves the protein at Arg 221 and near the C-terminus, producing stable 25, 13.4, and 2 kDa polypeptides [Torri-Tarelli, G., Vanoni, M. A., Negri, A., & Curti, B. (1990) J. Biol. Chem. 265, 21242-21246]. The 25 and 13.4 kDa polypeptides remain associated to form a nicked D-amino acid oxidase species. This nicked protein form maintains the ability to bind FAD, but exhibits altered catalytic efficiency toward the oxidation of various D-amino acids when compared to native DAAO. Changes in substrate specificity were first monitored by measuring the activity in the presence of different amino acid substrates at various times during proteolysis. Three amino acid substrates were then selected for further analysis of the properties of the nicked D-amino acid oxidase species produced by limited tryptic proteolysis: D-serine, D-arginine, and D-alanine. The three D-amino acids represented limiting cases of the observed changes of enzyme activity on nicking: loss of activity, increase of activity, and minor activity changes, respectively. D-serine was found to be no longer a substrate of D-amino acid oxidase. D-arginine exhibited a 2.5-fold increased apparent maximum velocity although its Km value increased 2-fold with the nicked enzyme in comparison to the native species. D-alanine was oxidized 1.5-fold faster by the nicked D-amino acid oxidase at infinite substrate concentration, and its Km value increased approximately 4-fold. The Kd for benzoate, which was determined kinetically with D-alanine as the enzyme substrate, increased 17-fold in the nicked species. Primary deuterium kinetic isotope effects on V and V/K during the oxidation of D-alanine were also measured. (D)V/K increased from 1.4 +/- 0.2 to 1.8 +/- 0.3 on nicking, while (D)V increased from 1.04 +/- 0.1 to 2.53 +/- 0.5. All the observed changes of the values of the kinetic parameters and of the observed isotope effects are consistent with the hypothesis that nicking of D-amino acid oxidase at position 221 decreases the strength of binding of both substrates and products to the enzyme active site. The information obtained by limited tryptic proteolysis nicely complements that gathered from the analysis of the three-dimensional structure of D-amino acid oxidase in complex with benzoate, which was recently determined [Mattevi, A., Vanoni, M. A., Todone, F., Rizzi, M., Teplyakov, A., Coda, A., Bolognesi, M., & Curti, B. (1996) Proc. Natl. Acad. Sci. U.S.A. 93, 7496-7501]. Arginine 221 is part of the 216-228 loop that covers the active site and contributes residues to substrate binding and catalysis. The limited proteolysis data support the hypothesis that this loop acts as a lid on the active site and controls both substrate specificity and the rate of turnover of D-amino acid oxidase.
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Affiliation(s)
- M A Vanoni
- Dipartimento di Fisiologia e Biochimica Generali, Universitá degli Studi di Milano, Italy
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Beretta A, Furci L, Burastero S, Cosma A, Dinelli ME, Lopalco L, DeSantis C, Tambussi G, Carrow E, Sabbatani S, Clerici M, Lazzarin A, Siccardi AG. HIV-1-specific immunity in persistently seronegative individuals at high risk for HIV infection. Immunol Lett 1996; 51:39-43. [PMID: 8811343 DOI: 10.1016/0165-2478(96)02553-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A growing number of reports indicates that certain groups of individuals who almost certainly have been exposed to human immunodeficiency virus (HIV), yet continue to exhibit no signs or symptoms of infection, often have subtle evidence of specific immunity. We studied such a high-risk (HR) cohort of persistently seronegative individuals with histories of long-term sexual exposure to an HIV-infected partner to look for evidence of both humoral and cellular immunity that might have been induced by exposure to the virus. Twenty-three heterosexual and four homosexual monogamous couples with discordant HIV status were included in the study. Twelve of the HR partners were studied for in vitro stimulation of peripheral blood mononuclear cells (PBMC) by HIV envelope-derived peptides. All 12 responded overwhelmingly to a peptide containing the fifth conserved region of gp120. By generating and cloning T cell lines specific for this peptide, we concluded that in these individuals the T cell response to the envelope is mainly focused on the carboxy-terminus region of gp120 and is characterized by an oligoclonal expansion of CD4+ T cells expressing the same TCR Eighteen HR partners and 37 HIV-1 seropositive subjects were tested for the presence of anti-CD4 antibodies (anti-CD4 Abs) using a recombinant CD4-based enzyme-linked immunosorbent assay (ELISA). Anti-CD4 Abs were detected in eight of the HR partners (six confirmed by Western blot) and in nine of the HIV-1 seropositive subjects (eight confirmed by Western blot). Results from binding competition assays with a panel of monoclonal anti-CD4 Abs suggested that the anti-CD4 Abs detected in the HR partners are directed toward epitopes that are induced by gp120 binding. Twenty-seven of the HR partners were tested for the presence of antibodies that cross-react with HLA class I and gp120 (anti-HLA Abs). Anti-HLA Abs were detected in 16 of the HR partner sera and in 4/94 sera from a control population of normal healthy blood donors. Taken together, the results suggest that in some individuals with a history of long-term exposure to HIV, specific immunity may develop in the absence of overt infection. The common trigger for these responses is gp120.
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Affiliation(s)
- A Beretta
- DIBIT and Infectious Diseases Clinic, S. Raffaele Scientific Institute, Milano, Italy
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Beretta A, Weiss SH, Rappocciolo G, Mayur R, De Santis C, Quirinale J, Cosma A, Robbioni P, Shearer GM, Berzofsky JA. Human immunodeficiency virus type 1 (HIV-1)-seronegative injection drug users at risk for HIV exposure have antibodies to HLA class I antigens and T cells specific for HIV envelope. J Infect Dis 1996; 173:472-6. [PMID: 8568315 DOI: 10.1093/infdis/173.2.472] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The question of whether persistently seronegative persons at high risk for human immunodeficiency virus type 1 (HIV-1) infection exhibit HIV-1-specific T cell responses and antibodies to HIV-1 envelope epitopes shared with selected HLAs was assessed. These antibodies are not detectable by conventional serologic methods. Envelope-specific helper T (Env-Th) cell responses and antibodies specific for the HIV/HLA epitopes were studied in 21 HIV-1-negative injection drug users (IDUs). HIV/HLA antibodies were detected in 7 (33.3%) of 21 IDUs and 4 (4.3%) of 94 low-risk controls. Env-Th cell responses were detected in 16 (76.2%) of 21 IDUs and in 2 (3.1%) of 65 low-risk controls. All HIV/HLA antibody-positive IDUs also had Env-Th cell responses. These findings confirm the presence of HIV-1-specific immunity in conventionally seronegative individuals. Further characterization of these responses could provide the basis for new preventive strategies.
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Affiliation(s)
- A Beretta
- Department of Biology and Technology, S. Raffaele Scientific Institute, Milan, Italy
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Segal N, Cosma A. [Accomodation paralysis as an important sign in the diagnosis of botulism]. Rev Chir Oncol Radiol O R L Oftalmol Stomatol Ser Oftalmol 1979; 23:37-8. [PMID: 451286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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21
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Venezia A, Cosma A, Briganti C. [Case of severe congenital ichthyosis]. Minerva Pediatr 1977; 29:1021-4. [PMID: 875978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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22
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Venezia A, Cosma A, Briganti C. [A case of congenital syphilis with osteopathy and meningitis]. Minerva Pediatr 1976; 28:2087-93. [PMID: 1012228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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23
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Cosma A, Luca I, Moldovan V, Toldan I. [Q fever in a zootechnical community in the District of Bihor]. Bacteriol Virusol Parazitol Epidemiol (Bucur) 1974; 19:271-4. [PMID: 4858336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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