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1.
Transbound Emerg Dis ; 65(1): e25-e31, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28497542

RESUMEN

Hepatitis E virus (HEV) is a zoonotic pathogen with a worldwide distribution, and infects several mammalian species, including pigs and wild boars, which are recognized as its natural reservoirs. The virus causes a usually self-limiting liver disease with a mortality rate generally below 1%, although mortality rates of 15%-25% have been recorded in pregnant woman. Chronic infections can also occur. The prevalence of HEV has been extensively studied in wild boars and pigs in northern Italy, where intensive pig herds are predominantly located. In contrast, few data have been collected in south-central Italy, where small pig herds are surrounded by large regional parks populated with heterogeneous wild fauna. In this study, 291 liver samples from wild boars caught in south-central Italy were analysed with the molecular detection of viral RNA. Our results confirm the circulation of HEV in these animals, with a mean prevalence of 13.7% (40 of 291). A nucleotide sequence analysis showed that the HEV strains were highly conserved within the same geographic areas. The wild boar HEV strains belonged to the HEV-3c subtype, which is frequently described in wild boars, and to an uncommon undefined subtype (HEV-3j-like).The viral prevalence detected is concerning because it could represent a potential risk to hunters, meat workers and consumers of wild boar liver and derivative products. The hypothesized inter-species transmission of HEV to pigs and the possibility that the virus maintains its virulence in the environment and the meat chain also present potential risks to human health, and warrant further investigations in the near future.


Asunto(s)
Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/veterinaria , Enfermedades de los Porcinos/virología , Animales , Geografía , Hepatitis E/epidemiología , Hepatitis E/transmisión , Hepatitis E/virología , Virus de la Hepatitis E/genética , Humanos , Italia/epidemiología , Hígado/virología , Filogenia , Prevalencia , ARN Viral/genética , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/transmisión , Zoonosis
2.
Biomed Pharmacother ; 96: 1445-1452, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29217162

RESUMEN

Treatment of pain has always been a major goal in the clinic, as it is related to several pathological conditions of inflammatory origin and surgical procedures, which are associated with inflammatory mediators. Understanding the molecular mechanisms underlying the association between inflammatory mediators and pain perception, from peripheral to central sensitization, can provide the basis for the development of new pharmacological treatments. Despite safety concerns, till date, the use of non-steroidal anti-inflammatory drugs (NSAIDs) has been shown to be efficacious, safe, and well tolerated by patients. Thus, choosing the appropriate administration route, developing new formulations and lowering the efficacious dose represent, currently, effective means of treating inflammation and relieving the pain, without inducing significant side effects.


Asunto(s)
Mediadores de Inflamación/metabolismo , Percepción del Dolor/fisiología , Dolor/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Dolor/tratamiento farmacológico
3.
Rev Sci Tech ; 33(1): 39-46, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25000776

RESUMEN

The European region has been, and remains, a global leader in the development of animal welfare policies. The region has a great diversity of cultures and religions, different levels of socio-economic development, and varied legislation, policies and practices. Nevertheless, there are common drivers for animal welfare policy based on a history of animal welfare ethics and obligations to animal users and society in general. A unifying goal of countries in the region is to achieve sustainable compliance with the World Organisation for Animal Health (OIE) standards on animal health and welfare. Ethics isthe overarching driver, supported by the actions of governmental, inter-governmental and non-governmental activities, markets and trade, science and knowledge. Historically, organisations involved in promoting animal welfare have tended to act in isolation. For example, non-governmental organisations (NGOs) have run campaigns to influence retailers and the welfare policies of their farmer suppliers. Increasingly, different organisations with common or complementary goals are working together. For example, competent authorities, inter-governmental bodies and NGOs have combined their efforts to address dog population control across several countries in the region. Also, animal welfare is becoming integrated into the corporate social responsibility targets of private companies. Science and knowledge, as drivers and tools, are assisting with the harmonisation of welfare standards, e.g. by providing a common basis for measuring welfare impacts through animal-based measures and widespread sharing of this information. Current trends suggest that there will be greater collaboration among the organisations driving change, and increasing convergence of animal welfare strategies and welfare assessment tools. The result will be increased harmonisation of animal welfare standards throughout the region.


Asunto(s)
Bienestar del Animal/legislación & jurisprudencia , Bienestar del Animal/normas , Política Pública/legislación & jurisprudencia , Política Pública/tendencias , Animales , Comercio , Europa (Continente) , Unión Europea , Internacionalidad
4.
Neurotoxicology ; 39: 25-34, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23954760

RESUMEN

Long-term exposure to high manganese (Mn) levels can lead to Parkinson-like neurological disorders. Molecular mechanisms underlying Mn cytotoxicity have been not defined. It is known that Mn induces apoptosis in PC12 cells and that this involves the activation of some signal transduction pathways. Although the role of phospholipids in apoptosis and signal transduction is well-known, the membrane phospholipid component in Mn-related damage has not yet been investigated. Phosphatidylserine (PS) facilitates protein translocation from cytosol to plasma membrane and PS exposure on the cell surface allows macrophage recognition of apoptotic cells. This study investigates the effects of MnCl2 on PS metabolism in PC12 cells, relating them to those on cell apoptosis. Apoptosis induction decreased PS radioactivity of PC12 cells incubated with radioactive serine. MnCl2 reduced PS radioactivity even under conditions that did not affect cell viability or PS exposure, suggesting that the effects on PS metabolism may represent an early event in cell apoptosis. Thus the latter conditions that also induced a greater PS decarboxylation were utilized for further investigating on the effects on PS synthesis, by measuring the activity and expression of PS-synthesizing enzymes, in cell lysates and in total cellular membranes (TM). Compared with corresponding controls, enzyme activity of MnCl2-treated cells was lower in cell lysates and greater in TM. Evaluating the expression of two isoforms of PS-synthesizing enzyme (PSS), PSSII was increased both in cell lysate and TM, while PSSI was unchanged. MnCl2 addition to control cell lysate reduced enzyme activity. These results suggest Mn plays a dual role on PS synthesis. Once inside the cell, Mn inhibits the enzyme/s, thus accounting for reduced PS synthesis in lysates and intact cells. On the other hand, it increases PSSII expression in cell membranes. The possibility that this occurs to counteract the direct effects of Mn ions on enzyme activity cannot be excluded. The effects on membrane enzyme activity and expression may also participate to PS exposure, observed at longer periods of treatment, by increasing membrane PS content.


Asunto(s)
Apoptosis/efectos de los fármacos , Cloruros/farmacología , Compuestos de Manganeso/farmacología , Fosfatidilserinas/metabolismo , Fosfatidilserinas/farmacología , Oligoelementos/farmacología , Animales , Anexina A5/metabolismo , Citocromos c/metabolismo , Fragmentación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Citometría de Flujo , Células PC12 , Ratas , Serina/metabolismo , Factores de Tiempo , Tritio/metabolismo
5.
Ann Ig ; 22(2): 131-46, 2010.
Artículo en Italiano | MEDLINE | ID: mdl-20476653

RESUMEN

On 6th April 2009, at 3.32 AM, there was in L'Aquila and in some neighbouring villages, after an earthquake swarm last some months, an earthquake of M(L) = 5.8 (Richter magnitude scale) on depth of 8.8 km. The event was sensed in a very broad area, till in Rome and Ancon. The operative committee of the Civil Protection Department immediately gathered and a first operating group was despatched in the epicentre; the voluntary association of civil protection were in a pre-alarm situation and then were activated. This work want describe all the activities from 6th April 2009 till 31th August 2009, giving too a synthesis of the normative lines in case of catastrophic events typology C, otherwise all that events impossible to manage without national intervention.


Asunto(s)
Terremotos , Salud Pública , Humanos , Italia , Trabajo de Rescate
6.
Eur J Ophthalmol ; 18(6): 895-902, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18988159

RESUMEN

PURPOSE: To describe a new scleral fixation foldable intraocular lens (IOL): the Ultima. METHODS: The novel IOL is a new scleral fixation acrylic hydrophilic foldable lens that offers a 360 degrees sulcus support due to its round geometry. It can be folded and inserted through a 4 mm clear cornea incision. Twenty-five eyes implanted with the Ultima lens were followed for 2 years. RESULTS: Twenty-two eyes showed visual improvement, two eyes had no functional improvement, and one eye had visual deterioration. The IOL remained well centered and showed no signs of tilting in all patients during the entire follow-up. CONCLUSIONS: The main advantages of the Ultima IOL include the lack of tilting and the minimum postoperative astigmatism. It also allows a clear retinal examination and provides an excellent barrier for silicone oil between vitreous cavity and anterior chamber.


Asunto(s)
Resinas Acrílicas , Implantación de Lentes Intraoculares/métodos , Lentes Intraoculares , Esclerótica/cirugía , Técnicas de Sutura , Adulto , Anciano , Anciano de 80 o más Años , Córnea/cirugía , Femenino , Estudios de Seguimiento , Humanos , Complicaciones Intraoperatorias , Masculino , Microcirugia/métodos , Persona de Mediana Edad , Complicaciones Posoperatorias , Diseño de Prótesis , Refracción Ocular/fisiología , Agudeza Visual/fisiología
7.
Chemosphere ; 61(11): 1672-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15939454

RESUMEN

We have measured the content of polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans (together defined as "dioxins") in 269 samples of food of animal origin collected through the regional veterinary services, covering the national territory. Quantification of the dioxins was accomplished by isotope dilution method, and toxic equivalents (TEQ) were calculated. The average daily food intake was obtained from two main sources: national data collected by the National Institute of Nutrition, and data from an ongoing cohort study on diet and cancer including 40,000 Italian subjects. The mean value of dioxins measured in food of animal origin was 0.144 +/- 0.266 pg-TEQ/g (range: 0.003-1.655 pg-TEQ/g). Fish was the item with the highest content. The estimated intake of dioxins with main food items of animal origin is presented. The major contribution to dioxins intake with food comes from cow milk and fish consumption. These results are in agreement with what observed in studies conducted in other countries, such as Germany, Finland, Japan, Spain, and are below the limits set by the European legislation.


Asunto(s)
Dioxinas/análisis , Dioxinas/toxicidad , Análisis de los Alimentos , Contaminación de Alimentos , Animales , Bovinos , Pollos , Dieta , Ingestión de Alimentos , Geografía , Humanos , Italia , Técnica de Dilución de Radioisótopos , Porcinos
8.
Vet Ital ; 41(3): 167-75, 2005.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20437377

RESUMEN

Shell eggs sampled at retail outlets in two large Italian cities were tested to assess their freshness, food safety and the presence of veterinary drug residues. Some samples were found to be irregular due to lack of compliance with freshness requirements or shells were tainted by micro-cracks and foreign material. The most severe case of non-compliance was due to the presence of veterinary drug residues that either exceeded either the maximum acceptable residue limits or drugs that were prohibited.

9.
Vet Ital ; 41(4): 265-79, 2005.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20437381

RESUMEN

Salmonella enterica serovars Enteritidis and Typhimurium are the serotypes most frequently isolated from human cases. Traditional surveillance systems, based on serological characterisation and epidemiology, are not able to identify these common strains that cause outbreaks in humans. Innovative techniques are therefore necessary to accurately characterise these serotypes and hence accelerate the identification of the primary sources. Within a larger study, the goal of which was to develop an active surveillance system for outbreaks of food-borne diseases, characterisation of 42 Salmonella strains was performed using molecular techniques (pulsed field gel electrophoresis [PFGE] and random amplified polymorphic DNA [RAPD]), together with the Kirby-Bauer antibiotic assay. Results showed that both techniques were unable to satisfactorily characterise the Enteritidis serotype, while only PFGE identified the Typhimurium serotype.

10.
Vet Ital ; 41(4): 239-48, 2005.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20437380

RESUMEN

The determination of the origin of foodborne diseases is one of the top priorities for the world health community. Gastroenteritis caused by zoonotic Salmonella serovars is one of the major threats to human health. It is essential that surveillance systems are able to monitor the incidence of human cases and to provide useful data to plan and implement effective prevention strategies. Surveillance systems generate information that is of value both for the early detection of infection and for the identification of epidemiological trends and risk factors. The authors describe a surveillance system for the identification of the sources of infection foodborne disease outbreaks caused by Salmonella in the Abruzzo region of Italy between April 2000 and October 2002.

11.
Vet Ital ; 40(1): 22-31, 2004.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20437385

RESUMEN

The Istituto Zooprofilattico dell'Abruzzo e del Molise 'G. Caporale' (IZS A&M) has been monitoring contamination of food by the polychlorinated dibenzodioxins (PCDD) and polychlorinated dibenzo-furans (PCDF) as part of the National Surveillance Plan (NSP) in Italy since 1999, on license from the Italian Ministry of Health. Between 1999 and 2000, 238 samples (including meat, fish, eggs, milk, fat, feedstuffs) were analysed. The results of the tests were expressed in terms of international toxic equivalents (I-TEQs from NATO/CCMS, 1988) and World Health Organization toxic equivalents (WHO-TEQs). These results showed contamination levels comparable to those detected in similar studies conducted in other European countries for products such as milk (mean: 0.81 pg I-TEQ/g fat), meat (mean: 0.73 pg I-TEQ/g fat) and fat (mean: 0.51 pg I-TEQ/g fat). The highest dioxin content was found in fish (mean: 5.28 pg I-TEQ/g fat) and fish feeds (mean 6.60 pg ITEQ/ g fat). These two matrices also showed complete duplication of contamination profiles. Other edible matrices (milk, meat, eggs) revealed the presence of HpCDD and OCDD. This could be due to the introduction into Italy of the animal feed additive choline chloride contaminated by these congeners.

12.
Eur J Ophthalmol ; 14(6): 575-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15638112

RESUMEN

PURPOSE: To describe a case of scleroretinal necrosis after a subconjunctival injection of gentamicin in a patient who had an episcleral retinal detachment that was surgically repaired. METHODS: Case presentation. RESULTS: Thinning of the sclera due to cryosurgery and the induced localized inflammatory response resulting from the surgical procedure, in addition to the effect of the sponge buckle itself, could have played an important role in accumulation and storage of gentamicin under and adjacent to the buckle after injection. The increasingly higher concentration of the drug under the buckle could have induced a greater penetration of gentamicin through the sclera, which could have been the cause of the scleral-chorio-retinal necrosis observed in this patient. CONCLUSIONS: Attention must be given to avoid side effects from subconjunctival injection of gentamicin.


Asunto(s)
Antibacterianos/efectos adversos , Gentamicinas/efectos adversos , Retina/patología , Desprendimiento de Retina/cirugía , Esclerótica/patología , Conjuntiva , Criocirugía , Drenaje , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Necrosis/inducido químicamente , Curvatura de la Esclerótica
13.
Minerva Endocrinol ; 27(1): 53-7, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11845114

RESUMEN

It seems somewhat difficult to exactly define the real number of case reports concerning the association of hyperfunctioning thyroid node and carcinoma; the overall incidence of this condition seems, however, to be very rare. Different inclusion criteria are probably a fairly relevant cause of variability in the number of cases reported during the years. A basic classification scheme, as the one here reported, may be of help in characterizing the different possible conditions: 1. the coexistence of carcinoma and focally hyperfunctioning tissue in the same gland but at different locations (not uncommon); 2. the presence of such a large tumour mass that it can compete with normal tissue for tracer uptake, despite being hormonogenetically uneffective in itself; 3. the carcinoma located in the hyperfunctioning adenoma; 4. the real hyperfunctioning carcinoma, where coincidence between hyperfunctioning tissue and malignancy is complete (very rare). Two cases are reported here, respectively belonging to the third and fourth of these categories (the most challenging from a diagnostic point of view). The matter is intrinsically poor from a statistical standpoint: it is therefore difficult to draw definitive conclusions on the subject in operative terms. It is however felt that the systematic evaluation of oncological risk in thyroid nodes, occasionally recommended in the literature, may be cumbersome and not necessarily cost-effective.


Asunto(s)
Adenocarcinoma Folicular/diagnóstico por imagen , Carcinoma Papilar/diagnóstico por imagen , Errores Diagnósticos , Pertecnetato de Sodio Tc 99m/farmacocinética , Neoplasias de la Tiroides/diagnóstico por imagen , Nódulo Tiroideo/diagnóstico por imagen , Adenocarcinoma Folicular/complicaciones , Adenocarcinoma Folicular/metabolismo , Adenocarcinoma Folicular/radioterapia , Adenocarcinoma Folicular/secundario , Adenocarcinoma Folicular/cirugía , Adenoma/complicaciones , Adenoma/diagnóstico por imagen , Adenoma/metabolismo , Adenoma/patología , Adulto , Carcinoma Papilar/secundario , Carcinoma Papilar/cirugía , Terapia Combinada , Femenino , Humanos , Hipertiroidismo/etiología , Radioisótopos de Yodo/uso terapéutico , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Persona de Mediana Edad , Neoplasias Primarias Múltiples , Cintigrafía , Radioterapia Adyuvante , Reoperación , Neoplasias de la Tiroides/complicaciones , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Tiroidectomía
14.
J Pharmacol Exp Ther ; 300(3): 1053-62, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11861815

RESUMEN

1,4-benzothiazine (1,4-B) derivatives exert numerous effects in vivo and in vitro, including neurotoxicity and antitumor cytotoxicity. To analyze the mechanisms responsible for 1,4-B-induced cytotoxicity, we performed experiments to evaluate the possible apoptotic effect. For that purpose, we used mouse thymocytes, a cell population well sensitive to induction of apoptosis that has been used to assay apoptosis in many experimental systems. Results indicate that a number of 1,4-B analogs are able to induce both thymocyte apoptosis in vitro and thymus cell loss in vivo. Moreover, analysis of the structure-activity relationship indicate that the sulfur (S) oxidation state, the presence of the carbonyl group, and the nature and position of the side chain modulate the apoptotic efficacy. Moreover, results of in vitro experiments show that the 1,4-B-induced apoptosis associates with different biochemical events including phosphatidylcholine-specific phospholipase C activation, acidic sphingomyelinase activation and ceramide generation, loss of mitochondrial membrane potential (DeltaPsi(m)) and cytochrome c release, and caspase-8, -9, and -3 activation. These results indicate that 1,4-B analogs induce apoptosis through a complex of biochemical events.


Asunto(s)
Apoptosis/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Tiazinas/farmacología , Animales , Caspasas/metabolismo , Ceramidas/biosíntesis , Grupo Citocromo c/metabolismo , Fragmentación del ADN , Activación Enzimática/efectos de los fármacos , Fluorometría , Potenciales de la Membrana/efectos de los fármacos , Ratones , Ratones Endogámicos C3H , Mitocondrias/efectos de los fármacos , Esfingomielina Fosfodiesterasa/metabolismo , Estimulación Química , Relación Estructura-Actividad , Linfocitos T/metabolismo , Tiazinas/química , Fosfolipasas de Tipo C/metabolismo
15.
Blood ; 98(3): 743-53, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11468175

RESUMEN

Previously a novel gene was identified that encodes a glucocorticoid-induced leucine zipper (GILZ) whose expression is up-regulated by dexamethasone. This study analyzed the role of GILZ in the control of T-cell activation and its possible interaction with nuclear factor kappaB (NF-kappaB). Results indicate that GILZ inhibits both T-cell receptor (TCR)-induced interleukin-2/interleukin-2 receptor expression and NF-kappaB activity. In particular, GILZ inhibits NF-kappaB nuclear translocation and DNA binding due to a direct protein-to-protein interaction of GILZ with the NF-kappaB subunits. Moreover, GILZ-mediated modulation of TCR-induced responses is part of a circuit because TCR triggering down-regulates GILZ expression. These results identify a new molecular mechanism involved in the dexamethasone-induced regulation of NF-kappaB activity and T-cell activation. (Blood. 2001;98:743-753)


Asunto(s)
Glucocorticoides/farmacología , Leucina Zippers/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Linfocitos T/inmunología , Factores de Transcripción/farmacología , Transporte Activo de Núcleo Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Dexametasona/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glucocorticoides/química , Glucocorticoides/inmunología , Humanos , Interleucina-2/metabolismo , Leucina Zippers/inmunología , FN-kappa B/metabolismo , Receptores de Antígenos de Linfocitos T/antagonistas & inhibidores , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Interleucina-2/metabolismo , Linfocitos T/citología , Linfocitos T/efectos de los fármacos , Factores de Transcripción/inmunología , Células Tumorales Cultivadas
17.
Mol Cell Biochem ; 211(1-2): 61-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11055548

RESUMEN

The exposure of phosphatidylserine toward the external surface of the membrane is a well-established event of programmed cell death. The possibility that an apoptotic stimulus influences the metabolism of this phospholipid could be relevant not only in relation to the previously mentioned event but also in relation to the capability of membrane phosphatidylserine to influence PKC activity. The present investigation demonstrates that treatment of mouse thymocytes with the apoptotic stimulus dexamethasone, enhances the incorporation of [3H]serine into phosphatidylserine. Cell treatment with dexamethasone also enhanced the activity of serine base exchange enzyme, assayed in thymocyte lysate. Both the effects were observed at periods of treatment preceding DNA fragmentation. The addition of unlabelled ethanolamine, together with [3H]serine to the medium containing dexamethasone-treated thymocytes lowered the radioactivity into phosphatidylserine. Serine base exchange enzyme activity was influenced by the procedure used to prepare thymocyte lysate and was lowered by the addition of fluoroaluminate, that is widely used as a G-protein activator. The increase of serine base exchange enzyme activity induced by dexamethasone treatment was observed independently by the procedure used to prepare cell lysate and by the presence or absence of fluoroaluminate.


Asunto(s)
Apoptosis , Dexametasona/farmacología , Transferasas de Grupos Nitrogenados/metabolismo , Fosfatidilserinas/metabolismo , Serina/metabolismo , Linfocitos T/efectos de los fármacos , Tritio/metabolismo , Compuestos de Aluminio/farmacología , Animales , Extractos Celulares , Células Cultivadas , Cicloheximida/farmacología , Citometría de Flujo , Fluoruros/farmacología , Ratones , Transferasas de Grupos Nitrogenados/antagonistas & inhibidores , Linfocitos T/citología , Linfocitos T/enzimología
18.
J Immunol ; 165(7): 3923-33, 2000 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11034400

RESUMEN

Group B Streptococcus (GBS) is a pathogen that has developed some strategies to resist host immune defenses. Because phagocytic killing is an important pathogenetic mechanism for bacteria, we investigated whether GBS induces apoptosis in murine macrophages. GBS type III strain COH31 r/s (GBS-III) first causes a defect in cell membrane permeability, then at 24 h, apoptosis. Apoptosis was confirmed by several techniques based on morphological changes and DNA fragmentation. Cytochalasin D does not affect apoptosis, suggesting that GBS-III needs not be within the macrophage cytoplasm to promote apoptosis. Inhibition of host protein synthesis prevents apoptosis, whereas inhibition of caspase-1 or -3, does not. Therefore, GBS can trigger an apoptotic pathway independent of caspase-1 and -3, but dependent on protein synthesis. Inhibition of apoptosis by EGTA and PMA, and enhancement of apoptosis by calphostin C and GF109203X suggests that an increase in the cytosolic calcium level and protein kinase C activity status are important in GBS-induced apoptosis. Neither alteration of plasma membrane permeability nor apoptosis were induced by GBS grown in conditions impeding hemolysin expression or when we used dipalmitoylphosphatidylcholine, which inhibited GBS beta-hemolytic activity, suggesting that GBS beta-hemolysin could be involved in apoptosis. beta-Hemolysin, by causing membrane permeability defects, could allow calcium influx, which initiates macrophage apoptosis. GBS also induces apoptosis in human monocytes but not in tumor lines demonstrating the specificity of its activity. This study suggests that induction of macrophage apoptosis by GBS is a novel strategy to overcome host immune defenses.


Asunto(s)
Apoptosis/inmunología , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/microbiología , Streptococcus agalactiae/inmunología , 1,2-Dipalmitoilfosfatidilcolina/farmacología , Animales , Animales no Consanguíneos , Apoptosis/efectos de los fármacos , Proteínas Bacterianas , Calcio/fisiología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Permeabilidad de la Membrana Celular/inmunología , Células Cultivadas , Medios de Cultivo/farmacología , Cicloheximida/farmacología , Fragmentación del ADN/inmunología , Espacio Extracelular/inmunología , Espacio Extracelular/metabolismo , Espacio Extracelular/microbiología , Femenino , Proteínas Hemolisinas/biosíntesis , Proteínas Hemolisinas/inmunología , Humanos , Macrófagos Peritoneales/enzimología , Macrófagos Peritoneales/ultraestructura , Masculino , Ratones , Monocitos/citología , Monocitos/inmunología , Monocitos/microbiología , Proteína Quinasa C/fisiología , Streptococcus agalactiae/crecimiento & desarrollo , Streptococcus agalactiae/fisiología , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas
20.
Therapie ; 55(1): 165-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10860020

RESUMEN

The immune T-cell compartment maintains the capability to respond to a wide variety of antigens (Ag). This whole process is regulated by lymphocyte apoptosis (programmed cell death, PCD) and involves the coordinated expression of a great number of genes including those coding for cytokines and their receptors, such as for example IL-2/IL-2R and the Fas/FasL systems and those coding for transcription factors, including the NF-kB complex, involved in T-cell activation and apoptosis in that they simultaneously activate cell suicide and an anti-death programme. This binary effect, PCD activation and inhibition, is due on one hand to GCH-induced activation of the caspases cascade and on the other to the induction of expression of a new gene that we have named GILZ. In fact, GILZ over-expression in transfected cells inhibits the sequential increase of NF-kB/DNA-binding activity, IL-2 production and IL-2R expression, and transcription of the Fas/FasL complex that follows TCR triggering and plays an important role in the control of T-lymphocyte apoptosis. These results indicate a new mechanism responsible for the GCH-mediated inhibition of T-cell death and activation that could contribute to anti-inflammatory and immunosuppressive efficacy.


Asunto(s)
Apoptosis/fisiología , Muerte Celular/fisiología , Glucocorticoides/fisiología , Animales , Humanos , Linfocitos T/fisiología
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