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1.
J Prev Med Hyg ; 60(1): E12-E17, 2019 Mar.
Article in English | MEDLINE | ID: mdl-31041405

ABSTRACT

INTRODUCTION: In recent years, a phenomenon known as "vaccine hesitancy" has spread throughout the world, even among health workers, determining a reduction in vaccination coverage (VC).A study aimed at evaluating VC among healthcare workers (HCWs) in 10 Italian cities (L'Aquila, Genoa, Milan, Palermo, Sassari, Catanzaro, Ferrara, Catania, Naples, Messina) was performed. MATERIALS AND METHODS: Annex 3 of the Presidential Decree n. 445 of 28 December 2000 was used to collect information on the vaccination status of HCWs. The mean and standard deviation (SD) were calculated with regard to the quantitative variable (age), while absolute and relative frequencies were obtained for categorical data (sex, professional profile, working sector, vaccination status). The connection between VC and the categorical variables was evaluated by chi-square method (statistical significance at p < 0.05). The statistical analyses were performed by SPSS and Stata software. RESULTS: A total of 3,454 HCWs participated in the project: 1,236 males and 2,218 females.The sample comprised: physicians (26.9%), trainee physicians (16.1%), nurses (17.2%) and other professional categories (9.8%). Low VC was generally recorded. Higher VC was found with regard to polio, hepatitis B, tetanus and diphtheria, while coverage was very low for measles, mumps, rubella, pertussis, chickenpox and influenza (20-30%). CONCLUSIONS: This study revealed low VC rates among HCWs for all the vaccinations. Measures to increase VC are therefore necessary in order to prevent HCWs from becoming a source of transmission of infections with high morbidity and/or mortality both within hospitals and outside.


Subject(s)
Nurses/statistics & numerical data , Physicians/statistics & numerical data , Vaccination Coverage/statistics & numerical data , Adult , Cross-Sectional Studies , Female , Health Personnel/statistics & numerical data , Humans , Infectious Disease Transmission, Professional-to-Patient , Italy , Male , Middle Aged
2.
Ann Ig ; 31(2 Supple 1): 13-24, 2019.
Article in English | MEDLINE | ID: mdl-30994160

ABSTRACT

INTRODUCTION: An adequate immunization of the health care workers is essential for infection prevention and control, to avoid consequences not only for them, but for all patients that the health care workers could infect causing serious damage and / or death. Unfortunately, to date, despite the presence of international and national guidelines (Law Decree 119/2017), the vaccination coverage was low, also because of the "vaccine hesitancy" spread among the same health care workers. In light of the above, the aim of our study was to investigate the vaccination coverage of healthcare workers of all the operational units present in our hospital and to evaluate differences between sex, age, professional profile and area of work. MATERIALS AND METHODS: A study was conducted from March to June 2018 to investigate the vaccination coverage of healthcare workers at the University hospital "G. Martino" of Messina; data were collected using a self-completion questionnaire based on Attachment 3 of Ministerial Circular 25233 of 18 August 2017. We verified any possible association between physicians and pediatricians and between age classes by the chi square method. Also, a logistic regression was used for each vaccination, considering the vaccination as the variable and the following covariates: type of operative unit, sex, age and area) in order to predict the probability of vaccination. RESULTS: We analyzed a sample of 822 health care workers (324 males and 498 females with an age of 49.5 ± 10.5 SD). The sample was made up of physicians (36%), nurses (21%) and other professional categories (43%). Analyzing the data we obtained vaccination coverages lower than the target required to guarantee "herd immunity"; higher vaccination coverages were found for females, physicians and the clinical area and - for influenza vaccination - in the older age groups and - for all the other vaccinations - in the younger groups. CONCLUSION: Data analysis revealed a lax attitude towards vaccinations by health care workers and the need for measures aimed at increasing vaccination their coverage to prevent them from becoming a source of dangerous outbreaks.


Subject(s)
Health Personnel/statistics & numerical data , Vaccination Coverage/statistics & numerical data , Adult , Age Distribution , Aged , Chi-Square Distribution , Female , Hospitals, University , Humans , Immunity, Herd , Italy , Logistic Models , Male , Medical Staff, Hospital/statistics & numerical data , Middle Aged , Nursing Staff, Hospital/statistics & numerical data , Pediatricians/statistics & numerical data , Sex Distribution , Surveys and Questionnaires , Vaccination Refusal , Young Adult
3.
J Prev Med Hyg ; 50(2): 121-6, 2009 Jun.
Article in English | MEDLINE | ID: mdl-20099444

ABSTRACT

The objective of this study was to evaluate and compare the safety, tolerability and immunogenicity for two seasonal influenza subunit vaccines, one with MF59 adjuvant (Fluad) and one without an adjuvant (Agrippal). A total of 195 subjects aged > or = 65 years were enrolled to receive one dose of vaccine intramuscularly, 96 were vaccinated with Fluad, 99 received Agrippal. Blood samples were taken from all subjects in order to assess their antibody titre by the haemagglutination inhibition assay (HI), before (Time 0) and after (Time 1: 28 +/- 7 days) vaccination, against the A/H3N2 (A/Moscow/10/99), A/H1N1 (A/New Caledonia/20/99) and B/Shandong/7/97 antigens contained in the influenza vaccine in the 2002/2003 influenza season for the northern hemisphere. A good humoral antibody response was detected for both vaccines, meeting all the criteria of EMEA. The number of subjects in whom > or = 4-fold increase in antibody titre was recorded, in comparison with the pre-vaccination value, proved to be lower in the group vaccinated with AgrippaPl than in those vaccinated with the adjuvated preparation. Fluad" exhibited better immunogenicity than Agrippal. This difference was probably linked to the potentiated immune stimulation exerted by the adjuvant molecules. These results take on a particular importance if we consider that the immune system is weaker in the elderly; the administration of an adjuvated vaccine in such subjects is clearly preferable in that it provides greater and more prolonged protection. Both vaccines were generally well tolerated; no severe adverse events occurred in any of the subjects vaccinated, confirming the excellent safety profile of Fluad and Agrippal.


Subject(s)
Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Adjuvants, Immunologic/administration & dosage , Adjuvants, Immunologic/adverse effects , Aged , Aged, 80 and over , Antibodies, Viral/blood , Female , Humans , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/immunology , Influenza B virus/immunology , Influenza Vaccines/adverse effects , Influenza Vaccines/immunology , Influenza, Human/immunology , Male , Vaccines/administration & dosage , Vaccines/adverse effects , Vaccines/immunology , Vaccines, Subunit/administration & dosage , Vaccines, Subunit/adverse effects , Vaccines, Subunit/immunology
4.
J Prev Med Hyg ; 50(4): 236-40, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20812520

ABSTRACT

INTRODUCTION: Rubella can have particularly serious effects on the product of conception if contracted during pregnancy. Thus, the main aim of rubella vaccination programmes is to prevent infection during pregnancy. MATERIALS AND METHODS: A seroepidemiological study was conducted from July 2006 to December 2007 on 1000 women of childbearing age, 15 to 45 years old, using specific rubivirus antibody assays, IgG and IgM. A questionnaire administered at the same time allowed us to survey how much women knew about this disease. In addition, MMR vaccine coverage rates were analysed for cohorts born in the local health districts of Messina for the period 1993-2006. RESULTS: An analysis of the replies given to the questionnaire showed an estimated 42.8% of the women to have immunity from rubella, while the serological study showed an immunity coverage rate of80.6%. Vaccination coverage in the local health districts regarding the first dose of MMR was 81% (cohorts 1993-2005), while the rate was only 24% for the second dose (cohorts 1993-2002). CONCLUSIONS: Both immunity coverage in women of childbearing age and that for newborns (for the cohort considered)fall below the 95% target set by the National Elimination Plan for Measles and Congenital Rubella (PNEM). It is therefore necessary to provide women with adequate information about the risks of rubella during pregnancy and about the benefits of vaccination, as well as to recoup subjects at risk or those whose immune status is unknown. Public health authorities also need to make continued efforts to increase the number of MMR vaccinations throughout the region.


Subject(s)
Health Knowledge, Attitudes, Practice , Measles-Mumps-Rubella Vaccine , Rubella Syndrome, Congenital/prevention & control , Vaccination/statistics & numerical data , Adolescent , Adult , Female , Humans , Infant, Newborn , Italy/epidemiology , Mass Screening , Middle Aged , Pregnancy , Rubella Syndrome, Congenital/epidemiology , Seroepidemiologic Studies
5.
Clin Exp Hypertens ; 30(8): 798-807, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19021029

ABSTRACT

The aim of the present investigation was to study the effects of choline and choline-containing phospholipids CDP-choline (CDPC) and L-alpha-glyceryl-phosphorylcholine (AGPC) on transglutaminase (TG) activity and expression in primary astrocyte cultures. TG is an important Ca(2+)-dependent protein that represents a normal constituent of nervous systems during fetal stages of development, playing a role in cell signal transduction, differentiation, and apoptosis. Confocal laser scanning microscopy (CLSM) analysis showed an increase of TG activity in astrocyte cultures treated with choline, CDPC, or AGPC at 0.1 microM or 1 microM concentrations. Comparatively, AGPC induced the most conspicuous effects enhancing monodansyl-cadaverine fluorescence both in cytosol and in nuclei, supporting the evidence of the important role played by AGPC throughout differentiation processes tightly correlated to nucleus-cytosol cross- talk during astroglial cells proliferation and development. Western blot analysis showed that in 24h 1 microM AGPC and choline-treated astrocytes increased TG-2, whereas no effect was observed in 24h 1 microM CDP-choline treated astrocytes. Our data suggest a crucial role of choline precursors during different stages of astroglial cell proliferation and differentiation in cultures.


Subject(s)
Astrocytes/enzymology , Cytidine Diphosphate Choline/pharmacology , Glycerylphosphorylcholine/pharmacology , Nootropic Agents/pharmacology , Transglutaminases/metabolism , Animals , Apoptosis/drug effects , Astrocytes/drug effects , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Rats , Rats, Wistar
6.
Neurochem Res ; 33(12): 2601-8, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18841472

ABSTRACT

Effects of acetylcholine and of the cholinergic precursors choline, cytidine 5'-diphosphocholine (CDP-choline) and alpha-glyceryl-phosphorylcholine (alpha-GPC) on transglutaminase (TG) and cyclin D1 expression were studied in primary astrocyte cultures by confocal laser microscopy (CLSM) with monodansyl-cadaverine uptake as a marker of enzyme activity and by immunochemistry (Western blotting). CLSM analysis showed an increased cytofluorescence in 0.1 microM choline-treated astrocytes. Treatment with CDP-choline dose-dependently increased TG. A total of 1 microM CDP-choline exposure in 14 days in vitro (DIV) astrocyte cultures increased cytofluorescence. A total of 1 microM alpha-GPC 24 h-treated cultures revealed increased cytofluorescence both in cytosol and nuclei. Western blot analysis showed an increased TG expression in cultures exposed for 24 h to 1 microM choline or alpha-GPC, whereas in 24 h 1 microM CDP-choline and acetylcholine-treated astrocytes TG expression was unaffected. Treatment with 1 microM acetylcholine reduced TG expression at 21 DIV. In cultures at 14 and 35 DIV cholinergic precursor treatment for 24 h induced a marked down-regulation of cyclin D1 expression, with reduced cyclin D1 expression in 1 microM alpha-GPC treated astrocytes. Our data suggest a role of cholinergic precursors investigated independent from acetylcholine on maturation and differentiation of astroglial cells in vitro, rather than on their growth, proliferation and development in culture.


Subject(s)
Acetylcholine/pharmacology , Astrocytes/drug effects , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Acetylcholine/chemistry , Animals , Astrocytes/cytology , Blotting, Western , Cells, Cultured , Rats , Rats, Wistar
7.
J Prev Med Hyg ; 49(1): 22-5, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18792530

ABSTRACT

INTRODUCTION: West Nile virus (WNV) is a mosquito-transmitted flavivirus widely distributed in Africa, Middle East, Asia, Southern Europe and in 1999 was first identified in the United States as a cause of disease in New York City. It mainly circulates among birds, but can infect many species of mammals. Epidemics can occur in rural as well as urban areas. METHODS: 1,280 sera were collected during 2006 from 80 stable workers, as jockey and grooms, 100 fowlers, 500 blood donors, 600 healthcare workers, 100 veterinary surgeons and 100 hunters in the Messina province to evaluate the prevalence of the WNV infection, by ELISA test, in relation to risk exposure or not. RESULTS: None of the 1280 subjects examined has shown positive for antibodies anti WN virus. CONCLUSION: Among the strategies of control and surveillance, finally, in our opinion, are and will be indispensable the programs of continuous antibody survey in all the risk categories and in the general population in order to succeed to preview which effects could have the presence of infections from WNV, also imported from other zones where the virus is constantly present, in future and which it could be the impact of geographic factors on the epidemic spread of the disease.


Subject(s)
Animal Technicians , Blood Donors , Health Personnel , Occupational Exposure , Occupational Health , West Nile Fever/epidemiology , West Nile virus/immunology , Zoonoses/epidemiology , Animals , Birds/virology , Enzyme-Linked Immunosorbent Assay , Epidemiologic Studies , Humans , Italy/epidemiology , Population Surveillance , Prevalence , Risk Factors , Seroepidemiologic Studies , West Nile Fever/transmission , Zoonoses/transmission
9.
J Neurosci Res ; 86(6): 1297-305, 2008 May 01.
Article in English | MEDLINE | ID: mdl-18041095

ABSTRACT

Type-2 transglutaminase (TG-2) is a multifunctional enzyme involved in the regulation of cell differentiation and survival that recently has been shown to play an emerging role in astrocytes, where it is involved in both proliferation and differentiation processes. Growth factors (GFs) such as EGF, basic fibroblast growth factor, insulin-like growth factor-I (IGF-I), and insulin (INS) are trophic and mitogenic peptides that participate in neuron-glia interactions and stimulate neuronal and astroglial proliferation and differentiation. Steroid hormones such as glucocorticoids and estrogens also play a pivotal role in neuronal and astroglial proliferation and differentiation and are key hormones in neurodegenerative and neuroprotective processes. We investigated the effects of the interaction of GFs with dexamethasone (DEX) or 17beta-estradiol (E(2)) on TG-2 activity and their expression in cultured astrocytes. We observed a significant increase in TG-2 activity and expression in astroglial cells treated for 24 hr with IGF-I, EGF, or INS. Priming of the cells with DEX or E(2), for 48 hr also led to an increase in TG-2 levels. When growth factors were present in the last 24 hr of the steroid treatment, a reduction in TG-2 expression and activity and a different subcellular TG-2 distribution were found. Our data indicate that steroid hormone-GF interaction may play an important role in astroglial function. The effect on TG-2 could be part of the regulation of intracellular pathways associated with the astrocyte response observed in physiological conditions and, possibly, also in neuropathological diseases.


Subject(s)
Astrocytes/metabolism , Dexamethasone/metabolism , Estradiol/metabolism , GTP-Binding Proteins/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Transglutaminases/metabolism , Animals , Blotting, Western , Cells, Cultured , Fluorescent Antibody Technique , Microscopy, Confocal , Protein Glutamine gamma Glutamyltransferase 2 , Rats , Steroids/metabolism
10.
J Prev Med Hyg ; 47(3): 110-3, 2006 Sep.
Article in English | MEDLINE | ID: mdl-17217188

ABSTRACT

A study on hepatitis B and C virus seroprevalence was carried out on blood samples from 327 municipal solid waste workers in Messina (Italy) to verify the hypothesis that this category of workers is at high risk for such diseases. The fact that 32.41% of all the subjects showed previous exposure to hepatitis B virus (HBV) substantiates the need to proceed with compulsory HBV vaccine prophylaxis in this category of workers, also in anticipation of possible medical legal litigations.


Subject(s)
Hepatitis B Antibodies/blood , Hepatitis B/epidemiology , Hepatitis C Antibodies/blood , Hepatitis C/epidemiology , Occupational Diseases/epidemiology , Occupational Exposure/analysis , Refuse Disposal , Adult , Aged , Hepatitis A Vaccines/administration & dosage , Hepatitis B/prevention & control , Hepatitis B Vaccines/administration & dosage , Hepatitis C/prevention & control , Humans , Immunization Programs , Italy/epidemiology , Middle Aged , Occupational Diseases/prevention & control , Occupational Exposure/adverse effects , Risk Assessment , Seroepidemiologic Studies
11.
J Prev Med Hyg ; 47(4): 142-5, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17263160

ABSTRACT

The aim of our research was to identify by bacterial genomic DNA analysis the prevalence of five different species of periodontopathogenic bacteria present in the subgingival biofilm, specifically: Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Bacterioides forsytus (Bf), Treponema denticola (Td). For the analysis we used the systematic Multiplex-PCR-microdent kit with species-specific primers. We studied a group of 48 subjects, 18 males and 30 females, from 18 to 78 years of age. The initial clinical screening enabled us to select, among the group analysed, 24 subjects with signs of active periodontopathy (Group A) and 24 patients without identifiable clinical evidence of the disease used as the control group (Group B). Within the two experimental groups (A and B), the test was found to be positive in 75% of subjects from group A, whereas the test was found to be negative in all the subjects from group B. Our research shows that the Multiplex-PCR system is reliable. Furthermore, the sensitivity and simplicity of this technique, as well as the decrease in working times and the possibility of identifying non-culturable bacteria, since the presence of viable organisms is not essential, make this technique indicated for the simultaneous identification of periodontopathogenic bacteria and might, in perspective, provide a more effective clinical alternative to the techniques of bacterial typing of the subgingival plaque.


Subject(s)
Adhesins, Bacterial/isolation & purification , DNA, Bacterial/analysis , Dental Plaque/microbiology , Gingiva/microbiology , Gram-Negative Bacteria/genetics , Periodontal Diseases/microbiology , Reverse Transcriptase Polymerase Chain Reaction/methods , Adhesins, Bacterial/genetics , Adolescent , Adult , Aged , Aggregatibacter actinomycetemcomitans/genetics , Aggregatibacter actinomycetemcomitans/isolation & purification , Bacteroides/genetics , Bacteroides/isolation & purification , Biofilms/growth & development , DNA, Bacterial/genetics , Female , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Humans , Male , Middle Aged , Porphyromonas gingivalis/genetics , Porphyromonas gingivalis/isolation & purification , Prevalence , Prevotella intermedia/genetics , Prevotella intermedia/isolation & purification , Reproducibility of Results , Sensitivity and Specificity , Treponema denticola/genetics , Treponema denticola/isolation & purification
12.
Ann Ig ; 17(1): 67-74, 2005.
Article in Italian | MEDLINE | ID: mdl-15869172

ABSTRACT

The management of healthcare professionals exposed to biological material which may potentially be contaminated with HIV HBVand HCV viruses, is of vital importance in acquiring precise epidemiological data regarding the type and means of exposure, and the efficacy or failure to apply recommended preventive measures. This will make it possible to assess over time which measures need to be implemented or improved. For these reasons we decided to analyze cases of occupational exposure to biological risk occurring in the University Hospital in Messina between 1998 and 2002. Our study highlighted in particular that the most frequently affected category was that of professional nurses (46.74%) and that only 31.72% of the healthcare workers who tested negative for HBsAb were administered vaccine prophylaxis also after the accident. Moreover, it emerged that there is the need to increase the amount and quality of information made available, by changing report forms, with the aim of identifying problems and risky behavior and procedures, and thus make ways to ensure the continued improvement of the accident prevention and management programmes. In fact, in the accident reporting procedure used, it was not possible to specify the precise way in which the accidents happened.


Subject(s)
Biological Products , Nursing Staff, Hospital/statistics & numerical data , Occupational Exposure/statistics & numerical data , Biological Products/adverse effects , Health Surveys , Humans , Italy/epidemiology , Needlestick Injuries , Retrospective Studies , Risk Factors
13.
Ann Ig ; 16(1-2): 341-9, 2004.
Article in Italian | MEDLINE | ID: mdl-15554539

ABSTRACT

The authors have carried a study on the knowledge of disinfection practices and the behaviour in operating room in order to control and prevent nosocomial infections. It is necessary for high percent of head nurses and nurses to have guidelines for the disinfection/sterilization procedures with the aim to avoid infections, but a large number of subjects don't know the correct procedures. The knowledge of a correct behaviour in the operating room is greater, although many of nursing staff don't wear the overshoes and the protective glasses. The statistical analysis show that nurses and the subjects with high degree have a greater knowledge of problems. It is important the planning of training and retraining courses directed to the improvement of technical knowledge and behaviour.


Subject(s)
Disinfection/methods , Disinfection/standards , Health Knowledge, Attitudes, Practice , Nursing Staff, Hospital , Surveys and Questionnaires
14.
Life Sci ; 75(22): 2643-52, 2004 Oct 15.
Article in English | MEDLINE | ID: mdl-15369700

ABSTRACT

Retinoids have been shown the most powerful inducers of transglutaminase activity, a well known marker of differentiation. In this work, we tested the effects of all-trans retinoic acid and EGF, used alone or in combination, on transglutaminase activity in a squamous, epithelial carcinoma cell line, HEp-2. We demonstrated that nanomolar EGF further enhances transglutaminase activity previously induced by all-trans retinoic acid. Confocal laser scanning microscopy revealed functional changes in transglutaminase activity localisation, at first restricted to the outermost region of cytosol, then diffused both in the membrane region and extracellular space. RT-PCR showed the presence of mRNA transcripts of different transglutaminases (1, 2, 3). Transglutaminase 2 expression was increased by either all-trans retinoic acid or EGF, and further up-regulated by the simultaneous addition of both substances. These effects were confirmed by Western blotting with transglutaminase 2 specific antibody. The results obtained by combined use of retinoic acid and EGF suggest that transglutaminase activity and expression are differently regulated, and that EGF-signalling can be involved in differentiation of epithelial carcinoma cells induced by retinoids.


Subject(s)
Carcinoma, Squamous Cell/enzymology , Epidermal Growth Factor/pharmacology , GTP-Binding Proteins/genetics , Gene Expression Regulation, Enzymologic/drug effects , Transglutaminases/genetics , Tretinoin/pharmacology , Carcinoma, Squamous Cell/pathology , Cell Differentiation , Cell Line, Tumor , GTP-Binding Proteins/metabolism , Humans , Protein Glutamine gamma Glutamyltransferase 2 , Transglutaminases/metabolism , Up-Regulation
15.
J Neurosci Res ; 74(1): 52-9, 2003 Oct 01.
Article in English | MEDLINE | ID: mdl-13130505

ABSTRACT

Although the precise role of transglutaminase in cell death is unknown, several findings demonstrate that tissue transglutaminase selectively accumulates in cells undergoing apoptosis both in vivo and in vitro. Calcium-dependent transglutaminase reactions are also implicated in several neurodegenerative diseases, including alterations in the release of excitatory amino acids. One prevalent theme in cell damage induced by excitotoxic stimuli in different regions of the CNS is that apoptosis may be executed by intracellular caspase proteases. Furthermore, the presence of functional ion channel-gated receptors in glial cells suggests that also astrocytes can be susceptible to glutamate's toxic effects. In this study, we demonstrated that prolonged exposure to glutamate (100 microM) of cultured astrocytes caused an increase in the expression of tissue transglutaminase (tTG). This effect was prevented by preincubation with GYKI 52466, an antagonist of AMPA/KA receptors. Glutamate exposure also promoted an increase in caspase-3 compared with control cultures. Confocal laser microscopy analysis demonstrated the presence of activated caspase-3 in the cytoplasm as well as in the nucleus. The inhibition of TG-catalyzed reactions by cystamine (1 mM) blocked the activation pathway of caspase-3, with an evident reduction of enzyme cleavage. These results suggest that glutamate increased both TG and caspase-3 in astroglial cells early in the excitotoxin-induced events.


Subject(s)
Astrocytes/drug effects , Caspase Inhibitors , Cerebral Cortex/drug effects , Cystamine/pharmacology , Glutamic Acid/pharmacology , Transglutaminases/antagonists & inhibitors , Animals , Astrocytes/enzymology , Caspase 3 , Caspases/metabolism , Cells, Cultured , Cerebral Cortex/enzymology , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Rats , Rats, Wistar , Transglutaminases/metabolism
16.
Brain Res ; 978(1-2): 24-30, 2003 Jul 18.
Article in English | MEDLINE | ID: mdl-12834894

ABSTRACT

Glutamate exposure of astroglial cells caused ligand-gated channel receptor activation, associated with excitotoxic cell response. We investigated the effects of 24 h glutamate exposure on transglutaminase in astrocytes primary cultures at 7, 14, and 21 days in vitro (DIV). Increases in enzyme activity were observed as a function of cell differentiation stage in glutamate-treated cultures. These effects were significantly reduced when GYKI 52466, an AMPA/KA receptors inhibitor, was added to the culture medium prior to incubation with glutamate. Microscopy observation on transglutaminase-mediated, fluorescent dansylcadaverine incorporation in living cells was consistent with these results. Western blotting analysis with monoclonal antibody showed that glutamate also up-regulated tissue transglutaminase expression, which reached the highest values in 14 DIV cultures. Confocal laser scanning microscopy analysis of immunostained astroglial cells showed a mainly cytoplasmic localisation of the enzyme both in control and treated cultures; nevertheless, counterstaining with the nuclear dye acridine orange demonstrated the presence of tissue transglutaminase also into the nucleus of glutamate-exposed and 21 DIV cells. The increases in enzyme expression and localisation in the nucleus of glutamate-treated astroglial cells may be part of biochemical alterations induced by excitotoxic stimulus.


Subject(s)
Astrocytes/drug effects , Benzodiazepines , Cadaverine/analogs & derivatives , Excitatory Amino Acid Agents/pharmacology , Glutamic Acid/pharmacology , Transglutaminases/metabolism , Animals , Animals, Newborn , Anti-Anxiety Agents/pharmacology , Astrocytes/metabolism , Blotting, Western/methods , Cadaverine/metabolism , Cells, Cultured , Dose-Response Relationship, Drug , Drug Interactions , Excitatory Amino Acid Antagonists/pharmacology , Glutamate-Ammonia Ligase/analysis , Immunohistochemistry/methods , Microscopy, Confocal/methods , Rats , Rats, Wistar , Time Factors , Transglutaminases/analysis
17.
J Virol ; 75(22): 10843-55, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11602725

ABSTRACT

Human immunodeficiency virus (HIV)-induced immunodeficiency is characterized by progressive loss of CD4(+) T cells associated with functional abnormalities of the surviving lymphocytes. Increased susceptibility to apoptosis and loss of proper cell cycle control can be observed in lymphocytes from HIV-infected individuals and may contribute to the lymphocyte dysfunction of AIDS patients. To better understand the relation between T-cell activation, apoptosis, and cell cycle perturbation, we studied the effect of exogenous interleukin-2 (IL-2) administration on the intracellular turnover of phase-dependent proteins. Circulating T cells from HIV-infected patients display a marked discrepancy between a metabolic profile typical of G(0) and a pattern of expression of phase-dependent proteins that indicates a more-advanced position within the cell cycle. This discrepancy is enhanced by in vitro activation with ConA and ultimately results in a marked increase of apoptotic events. Conversely, treatment of lymphocytes with IL-2 alone restores the phase-specific pattern of expression of cell cycle-dependent proteins and is associated with low levels of apoptosis. Interestingly, exogenous IL-2 administration normalizes the overall intracellular protein turnover, as measured by protein synthesis, half-life of newly synthesised proteins, and total protein ubiquitination, thus providing a possible explanation for the effect of IL-2 on the intracellular kinetics of cell cycle-dependent proteins. The beneficial effect of IL-2 administration is consistent with the possibility of defective IL-2 function in vivo, which is confirmed by the observation that lymphocytes from HIV-infected patients show abnormal endogenous IL-2 paracrine/autocrine function upon in vitro mitogen stimulation. Overall these results confirm that perturbation of cell cycle control contributes to HIV-related lymphocyte dysfunction and, by showing that IL-2 administration can revert this perturbation, suggest a new mechanism of action of IL-2 therapy in HIV-infected patients.


Subject(s)
Cell Cycle/drug effects , HIV Infections/immunology , Interleukin-2/pharmacology , Lymphocytes/drug effects , Antiretroviral Therapy, Highly Active , Cell Nucleolus , Cysteine Endopeptidases/biosynthesis , HIV Infections/drug therapy , Humans , Interleukin-2/biosynthesis , Lymphocytes/physiology , Multienzyme Complexes/biosynthesis , Ornithine Decarboxylase/biosynthesis , Proteasome Endopeptidase Complex
18.
Blood ; 97(6): 1756-64, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11238118

ABSTRACT

Human immunodeficiency virus (HIV)-infection is characterized by loss of CD4+ T cells associated with high levels of immune activation, T-cell proliferation, and lymphocyte apoptosis. To investigate the role of intrinsic perturbations of cell-cycle control in the immunopathogenesis of acquired immunodeficiency syndrome (AIDS), we studied the expression of cell-cycle-dependent proteins in lymphocytes from HIV-infected patients. Cyclin B1 expression, Nucleolar Organizer Regions (NORs) number, and NORs area of distribution were all consistently increased in HIV-infected patients, but returned to normal after effective antiretroviral therapy, suggesting that viral replication is directly implicated in the genesis of the observed changes. Analysis of cyclin B1 intracellular turnover showed that the increased cyclin B1 expression is (1) caused by defective degradation in the presence of normal rates of synthesis, and (2) is temporally associated with decreased levels of ubiquitination. After in vitro activation of lymphocytes from healthy individuals, cyclin B1 and cdc25 expression and ubiquitination, p34 cdc2 activity, NORs morphology, and C23/nucleolin localization showed a 72- to 96-hour cyclic pattern that led to a biologic state similar to baseline. On the contrary, complex but consistent changes of the same indices followed activation of T lymphocytes from HIV-infected patients, resulting in a 5-fold increase in apoptosis. Overall, our data indicate that a profound dysregulation of cell-cycle control is present in lymphocytes from HIV-infected patients. This finding may provide a novel biologic link between immune activation, accelerated lymphocyte turnover, and increased apoptosis during HIV infection.


Subject(s)
Cell Cycle Proteins/metabolism , HIV Infections/pathology , Lymphocytes/pathology , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use , Apoptosis , CDC28 Protein Kinase, S cerevisiae/metabolism , Cell Cycle , Cyclin B/drug effects , Cyclin B/metabolism , Cyclin B1 , HIV Infections/drug therapy , Humans , Kinetics , Nucleolus Organizer Region/drug effects , Phosphoproteins/metabolism , cdc25 Phosphatases/metabolism
19.
AIDS ; 13(10): 1159-64, 1999 Jul 09.
Article in English | MEDLINE | ID: mdl-10416518

ABSTRACT

OBJECTIVE: To study the role of cell cycle regulation during HIV infection by investigating in vivo and in vitro cyclin B and p34 cdc kinase expression. METHODS: Cyclin B expression was analysed by Western blot in CD4 and CD8 cells from 25 HIV-infected patients and 24 uninfected individuals. In eight patients, a sequential analysis was performed after initiation of antiretroviral therapy (ART), and correlations with CD4 cell count and HIV viremia were studied. Sequential changes in cyclin B expression and p34 cdc kinase expression and activity were also studied in lymphocytes activated in vitro with phytohaemagglutinin (PHA). RESULTS: Lymphocytes from untreated HIV-infected patients demonstrate persistent in vivo overexpression of cyclin B in both CD4 and CD8 cell subpopulations. When cells are stimulated to proliferate in vitro, biochemical events that characterize the entrance into the cell cycle [ornithine decarboxylase (ODC) activity, interleukin 2 production, interleukin 2 alpha-chain receptor (IL-2R, CD25) expression, total protein synthesis, total DNA synthesis] show similar timing and sequence in lymphocytes from HIV-infected and uninfected individuals. However, in peripheral blood lymphocytes (PBL) from HIV-infected patients, cyclin B and p34 cdc kinase show premature expression during the cell cycle. Both in vivo cyclin B overexpression and in vitro unscheduled cyclin B expression were almost completely reversed 2-4 weeks after initiation of effective ART. CONCLUSION: Increased and unscheduled expression of cyclin B and p34 cdc kinase is consistently observed in CD4 and CD8 cells from HIV-infected patients, both in vivo and after in vitro mitogenic stimulation. These alterations correlate with the level of viremia and may provide a link between the perturbation of lymphocyte proliferative homeostasis and the exaggerated propensity towards apoptosis.


Subject(s)
CDC2 Protein Kinase/metabolism , Cyclin B/biosynthesis , HIV Infections/immunology , T-Lymphocytes/metabolism , Apoptosis , Blotting, Western , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Enzyme Activation , HIV Infections/virology , Humans , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Lymphocyte Activation , RNA, Viral/blood , T-Lymphocytes/immunology , T-Lymphocytes/physiology
20.
J Neuroimmunol ; 80(1-2): 87-92, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9413262

ABSTRACT

Beta-endorphin (beta-end) was investigated for its ability to influence sequential metabolic events that accompany the movements of T-lymphocytes into the cell cycle. When cultured lymphocytes are exposed to this endogenous opioid peptide an increase in polyamine transport across cell membrane is observed. This membrane modification is an early cell cycle event, whose enhancement leads to the intracellular polyamine accumulation. It is shown that beta-end is able to enhance spermidine transport and that the exposition of cells to this peptide is perceived as an apoptotic signal. The possible relationship between induction of apoptotic death and enhancement of polyamine uptake is discussed.


Subject(s)
Cell Cycle/drug effects , Lymphocytes/cytology , Lymphocytes/drug effects , beta-Endorphin/pharmacology , Apoptosis/drug effects , Cell Death/drug effects , Cell Division/drug effects , Cells, Cultured , DNA/biosynthesis , Flow Cytometry , G1 Phase/drug effects , Humans , Interphase/drug effects , Intracellular Fluid/metabolism , Lymphocyte Activation/drug effects , Lymphocytes/metabolism , Polyamines/metabolism , Protein Biosynthesis , S Phase/drug effects
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