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1.
Nat Nanotechnol ; 18(8): 957-966, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157020

RESUMEN

The varied transcriptomic response to nanoparticles has hampered the understanding of the mechanism of action. Here, by performing a meta-analysis of a large collection of transcriptomics data from various engineered nanoparticle exposure studies, we identify common patterns of gene regulation that impact the transcriptomic response. Analysis identifies deregulation of immune functions as a prominent response across different exposure studies. Looking at the promoter regions of these genes, a set of binding sites for zinc finger transcription factors C2H2, involved in cell stress responses, protein misfolding and chromatin remodelling and immunomodulation, is identified. The model can be used to explain the outcomes of mechanism of action and is observed across a range of species indicating this is a conserved part of the innate immune system.


Asunto(s)
Nanoestructuras , Dedos de Zinc , Dedos de Zinc/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Perfilación de la Expresión Génica , Proteínas de Plantas
2.
Nat Commun ; 11(1): 4994, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33020485

RESUMEN

Serogroup B meningococcus (MenB) is a leading cause of meningitis and sepsis across the world and vaccination is the most effective way to protect against this disease. 4CMenB is a multi-component vaccine against MenB, which is now licensed for use in subjects >2 months of age in several countries. In this study, we describe the development and use of an ad hoc protein microarray to study the immune response induced by the three major 4CMenB antigenic components (fHbp, NHBA and NadA) in individual sera from vaccinated infants, adolescents and adults. The resulting 4CMenB protein antigen fingerprinting allowed the identification of specific human antibody repertoire correlating with the bactericidal response elicited in each subject. This work represents an example of epitope mapping of the immune response induced by a multicomponent vaccine in different age groups with the identification of protective signatures. It shows the high flexibility of this microarray based methodology in terms of high-throughput information and minimal volume of biological samples needed.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Adolescente , Adulto , Anticuerpos Antibacterianos/sangre , Niño , Preescolar , Mapeo Epitopo , Humanos , Lactante , Infecciones Meningocócicas/prevención & control , Biblioteca de Péptidos , Análisis por Matrices de Proteínas , Determinación de Anticuerpos Séricos Bactericidas , Adulto Joven
3.
Water Sci Technol ; 73(4): 751-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26901717

RESUMEN

The lack of geometrical and hydraulic information about sewer networks often excludes the adoption of in-deep modeling tools to obtain prioritization strategies for funds management. The present paper describes a novel statistical procedure for defining the prioritization scheme for preventive maintenance strategies based on a small sample of failure data collected by the Sewer Office of the Municipality of Naples (IT). Novelty issues involve, among others, considering sewer parameters as continuous statistical variables and accounting for their interdependences. After a statistical analysis of maintenance interventions, the most important available factors affecting the process are selected and their mutual correlations identified. Then, after a Box-Cox transformation of the original variables, a methodology is provided for the evaluation of a vulnerability map of the sewer network by adopting a joint multivariate normal distribution with different parameter sets. The goodness-of-fit is eventually tested for each distribution by means of a multivariate plotting position. The developed methodology is expected to assist municipal engineers in identifying critical sewers, prioritizing sewer inspections in order to fulfill rehabilitation requirements.


Asunto(s)
Aguas del Alcantarillado/análisis , Administración de Residuos/estadística & datos numéricos , Ciudades , Análisis Multivariante , Probabilidad , Administración de Residuos/métodos
4.
Vaccine ; 31(42): 4827-33, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23965218

RESUMEN

Glycoconjugate vaccines are among the most effective and safest vaccines ever developed. Diphtheria toxoid (DT), tetanus toxoid (TT) and CRM197 have been mostly used as protein carriers in licensed vaccines. We evaluated the immunogenicity of serogroup A, C, W-135 and Y meningococcal oligosaccharides conjugated to CRM197, DT and TT in naïve mice. The three carriers were equally efficient in inducing an immune response against the carbohydrate moiety in immunologically naïve mice. The effect of previous exposure to different dosages of the carrier protein on the anti-carbohydrate response was studied using serogroup A meningococcal (MenA) saccharide conjugates as a model. CRM197 showed a strong propensity to positively prime the anti-carbohydrate response elicited by its conjugates or those with the antigenically related carrier DT. Conversely in any of the tested conditions TT priming did not result in enhancement of the anti-carbohydrate response elicited by the corresponding conjugates. Repeated exposure of mice to TT or to CRM197 before immunization with the respective MenA conjugates resulted in a drastic suppression of the anti-carbohydrate response in the case of TT conjugate and only in a slight reduction in the case of CRM197. The effect of carrier priming on the anti-MenA response of DT-based conjugates varied depending on their carbohydrate to protein ratio. These data may have implications for human vaccination since conjugate vaccines are widely used in individuals previously immunized with DT and TT carrier proteins.


Asunto(s)
Proteínas Bacterianas/administración & dosificación , Toxoide Diftérico/administración & dosificación , Portadores de Fármacos/administración & dosificación , Vacunas Meningococicas/inmunología , Toxoide Tetánico/administración & dosificación , Animales , Vacunas Meningococicas/administración & dosificación , Ratones , Neisseria meningitidis Serogrupo A/inmunología , Neisseria meningitidis Serogrupo C/inmunología , Neisseria meningitidis Serogrupo W-135/inmunología , Neisseria meningitidis Serogrupo Y/inmunología , Polisacáridos Bacterianos/inmunología , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/inmunología
5.
J Fish Biol ; 80(5): 2112-21, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22497418

RESUMEN

The aim of this investigation was to assess the effects of nonylphenol (NP), an oestrogen-like environmental pollutant, on the vitellogenin (VTG) synthesis in adult males of the aplacental viviparous cartilaginous fish Torpedo marmorata. The VTG recovery in males is considered a biomarker of xeno-oestrogenic pollution as this lipophosphoglycoprotein is physiologically induced by oestrogens only in females of oviparous and ovoviparous vertebrates. Using in situ hybridization and immunohistochemistry, T. marmorata males injected with nonylphenol showed the presence of VTG in the liver and the kidney. In particular, vtg messenger (m)RNA and VTG protein were expressed in the liver, whereas in the kidney cells only the presence of VTG was recorded. By contrast, no expression for VTG was detected in the testis. These results demonstrate that in T. marmorata NP induces the expression of vtg only in the liver; the presence of VTG in the kidney and its absence in the testis are discussed.


Asunto(s)
Fenoles/farmacología , Torpedo/metabolismo , Vitelogeninas/biosíntesis , Animales , Inmunohistoquímica , Hibridación in Situ , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Testículo/efectos de los fármacos , Testículo/metabolismo , Contaminantes Químicos del Agua/farmacología
6.
Clin Vaccine Immunol ; 17(12): 1952-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20962212

RESUMEN

The objective of this study was to evaluate the efficacy of influenza and meningococcal vaccines in healthy subjects exposed to the anti-interleukin-1ß (anti-IL-1ß) monoclonal antibody canakinumab. This was an open-label, parallel group, randomized, single-center study of healthy subjects (aged 18 to 45 years). At baseline, antibody (Ab) titers were measured and subjects were randomized (1:1) to a single 300-mg canakinumab dose administered subcutaneously (s.c.) or received no treatment (control group). After 2 weeks, subjects were treated with inactivated, unadjuvanted influenza and conjugated group C meningococcal (MenC) vaccines, administered intramuscularly (i.m.). The primary efficacy variable was the response (≥ 2-fold increase in Ab titer in ≥ 2 of 3 influenza virus strains) after 4 weeks in subjects treated with canakinumab compared to the control group. Secondary efficacy variables were the antibody response to vaccines at different thresholds and time points. Fifty-one of 112 subjects screened were randomized to canakinumab (n = 25) or the control group (n = 26). Antibody responses to vaccinations measured against different influenza virus strains and one MenC strain at 4 weeks were comparable in the canakinumab and control groups. The primary efficacy variable, the response to influenza vaccination (≥ 2-fold increase in Ab titer in ≥ 2 of 3 serotypes) at 4 weeks, was shown in 24/25 subjects in the canakinumab group compared to 25/25 subjects in the control group. Antibody responses remained comparable in the two groups at the different time points assessed. Headache was the most frequently reported adverse event. No deaths or serious adverse events were reported during the study. We concluded that a single dose of 300 mg canakinumab s.c. does not affect the induction or persistence of antibody responses after vaccination with unadjuvanted influenza or alum-adjuvanted MenC vaccines in healthy subjects.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Factores Inmunológicos/administración & dosificación , Vacunas contra la Influenza/inmunología , Interleucina-1beta/antagonistas & inhibidores , Vacunas Meningococicas/inmunología , Adolescente , Adulto , Anciano , Anticuerpos Antibacterianos/sangre , Anticuerpos Bloqueadores/administración & dosificación , Anticuerpos Monoclonales Humanizados , Anticuerpos Antivirales/sangre , Interacciones Farmacológicas , Femenino , Cefalea/inducido químicamente , Experimentación Humana , Humanos , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/efectos adversos , Inyecciones Intramusculares , Masculino , Vacunas Meningococicas/administración & dosificación , Vacunas Meningococicas/efectos adversos , Persona de Mediana Edad , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Adulto Joven
7.
Rev Neurol ; 49(1): 13-7, 2009.
Artículo en Español | MEDLINE | ID: mdl-19557694

RESUMEN

AIMS: The purpose of this study was to evaluate the benefits of preoperative embolisation with an absorbable gelatine sponge in selected intracranial meningiomas. PATIENTS AND METHODS: We performed a retrospective study of a series of 33 patients who had undergone surgery for meningiomas with a diameter of over 4 cm between the years 2000 and 2007. Two groups were analysed: group A (n = 16) with preoperative embolisation and group B (n = 17) without it. Eligibility criteria for embolisation were: exclusive or predominant irrigation through the external carotid artery, high tumour flow and pronounced vascularisation through the pial branches. The location of the lesion was evaluated preoperatively; blood losses, number of units of blood transfused, surgery time and surgeon's opinion were evaluated intraoperatively. RESULTS: A statistically significant difference was found between the group of embolised patients and those who had not been embolised as far as surgery time (217.5 +/- 69.61 versus 291.76 +/- 56.94 min; p =< 0.002) and blood loss (613.75 +/- 231.42 versus 987.65 +/- 206.68 mL; p => 0.001) were concerned. A positive coloration (r = 0.568; p = 0.001) was found between surgery time and blood loss. No statistically significant relation was observed between age and the number of units of blood transfused. Embolisation was considered to be beneficial by 75% of surgeons. CONCLUSIONS: Preoperative embolisation with an absorbable gelatine sponge in patients with intracranial meningiomas with a diameter above 4 cm and exclusive or predominant irrigation by the external carotid artery is effective and safe; it also reduces intraoperative bleeding and surgery time.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Embolización Terapéutica , Esponja de Gelatina Absorbible , Meningioma/cirugía , Adulto , Anciano , Embolización Terapéutica/instrumentación , Embolización Terapéutica/métodos , Femenino , Humanos , Masculino , Meningioma/patología , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
8.
Ann Oncol ; 19(11): 1894-902, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18628242

RESUMEN

BACKGROUND: The relative contribution to gastric cancer (GC) risk of variants in genes that determine the inflammatory response remains mostly unknown and results from genotyping studies are inconsistent. PATIENTS AND METHODS: A nested case-control study within the prospective European Prospective Investigation into Cancer and Nutrition cohort was carried out, including 248 gastric adenocarcinomas and 770 matched controls. Twenty common polymorphisms at cytokine genes [interleukin (IL)1A, IL1B, IL1RN, IL4, IL4R, IL6, IL8, IL10, IL12A, IL12B, lymphotoxin alpha and tumor necrosis factor (TNF)] were analyzed. Antibodies against Helicobacter pylori (Hp) and CagA were measured. RESULTS: IL1RN 2R/2R genotype [odds ratio (OR) 2.43; 95% confidence interval (CI) 1.19-4.96] and allele IL1RN Ex5-35C were associated with an increased risk of Hp(+) non-cardia GC. IL8 -251AA genotype was associated with a decreased risk of Hp(+) non-cardia GC (OR 0.51; 95% CI 0.32-0.81), mainly of the intestinal type. These associations were not modified by CagA status. Carriers of IL1B -580C and TNF -487A alleles did not associate with an increased risk. A moderately increased risk of Hp(+) non-cardia GC for IL4R -29429T variant was observed (OR 1.74; 95% CI 1.15-2.63). CONCLUSION: This prospective study confirms the association of IL1RN polymorphisms with the risk of non-cardia GC and indicates that IL8 -251T>A may modify the risk for GC.


Asunto(s)
Adenocarcinoma/genética , Citocinas/genética , Neoplasias Gástricas/genética , Adenocarcinoma/epidemiología , Adulto , Anciano , Estudios de Casos y Controles , Europa (Continente)/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos , Humanos , Interleucinas/genética , Linfotoxina-alfa/genética , Masculino , Persona de Mediana Edad , Estado Nutricional , Polimorfismo Genético , Estudios Prospectivos , Neoplasias Gástricas/epidemiología , Factor de Necrosis Tumoral alfa/genética
9.
Clin Vaccine Immunol ; 15(2): 253-9, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18003811

RESUMEN

The objective of this study was to evaluate and compare both the safety and tolerability and the humoral and cell-mediated immune responses for two influenza virus subunit vaccines, one with MF59 adjuvant (Fluad) and one without an adjuvant (Agrippal), in healthy and in human immunodeficiency virus type 1 (HIV-1)-infected adult individuals. To achieve this aim, an open, randomized, comparative clinical trial was performed during the 2005-2006 season. A total of 256 subjects were enrolled to receive one dose of vaccine intramuscularly. Blood samples were taken at the time of vaccination and at 1 and 3 months postvaccination. A good humoral antibody response was detected for both vaccines, meeting all the criteria of the Committee for Medical Products for Human Use. After Beyer's correction for prevaccination status, Fluad exhibited better immunogenicity than Agrippal, as shown from the analysis of the geometric mean titers, with significant differences for some virus strains; however, no definitive conclusions on the clinical significance of such results can be drawn, because the method used to estimate antibody response is currently nonstandard for influenza virus vaccines. Significant induction of an antigen-specific CD4+ T-lymphocyte proliferative response was detected at all time points after immunization, for both the vaccines, among HIV-1-seronegative subjects. This was different from what was observed for HIV-1-infected individuals. In this group, significance was not reached at 30 days postvaccination (T30) for those immunized with Agrippal. Also when data were compared between treatment groups, a clear difference in the response at T30 was observed in favor of Fluad (P = 0.0002). The safety profiles of both vaccines were excellent. For HIV-1-infected individuals, no significant changes either in viremia or in the CD4+ cell count were observed at any time point. The results showed good safety and immunogenicity for both vaccines under study for both uninfected and HIV-1-infected adults, confirming current recommendations for immunization of this high-risk category.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/inmunología , Polisorbatos/administración & dosificación , Escualeno/administración & dosificación , Adolescente , Adulto , Anciano , Anticuerpos Antivirales/sangre , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/inmunología , Proliferación Celular , Células Cultivadas , Femenino , Infecciones por VIH/inmunología , Humanos , Gripe Humana/prevención & control , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Vacunas de Subunidad/efectos adversos , Vacunas de Subunidad/inmunología , Viremia
10.
Vaccine ; 25(46): 7927-30, 2007 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-17920733

RESUMEN

Caprine herpesvirus 1 provides a unique virus-animal model to investigate potential tools applicable for the therapy and prophylaxis of genital herpesvirus infections of humans. In order to evaluate the efficacy of mucosal immunization in the goat model, an inactivated CpHV-1 vaccine was adjuvated with the enzymatically inactive mutant of the heat-labile enterotoxin of Escherichia coli, LTK63, and used to immunize goats by the vaginal route, by administering two doses at a 3-week interval. The mucosal vaccine was safe, as neither local nor systemic reactions were associated with the vaccine administration. The vaccinated animals displayed high levels of secretory IgA and were significantly protected after challenge with the virulent CpHV-1 strain, with marked decrease in virus shedding, while the unvaccinated goats were not. These findings suggest that mucosal immunization is potentially exploitable in the control of genital infection by herpesviruses.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Toxinas Bacterianas/farmacología , Enterotoxinas/farmacología , Proteínas de Escherichia coli/farmacología , Enfermedades de las Cabras/prevención & control , Herpes Genital/prevención & control , Vacunas contra Herpesvirus/farmacología , Inmunidad Mucosa/efectos de los fármacos , Mutación , Varicellovirus/inmunología , Adyuvantes Inmunológicos/genética , Animales , Anticuerpos Antivirales/inmunología , Toxinas Bacterianas/genética , Toxinas Bacterianas/inmunología , Modelos Animales de Enfermedad , Enterotoxinas/genética , Enterotoxinas/inmunología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/inmunología , Enfermedades de las Cabras/genética , Enfermedades de las Cabras/inmunología , Cabras , Herpes Genital/genética , Herpes Genital/inmunología , Herpes Genital/veterinaria , Vacunas contra Herpesvirus/inmunología , Humanos , Inmunoglobulina A/inmunología , Vacunas Atenuadas/inmunología , Vacunas Atenuadas/farmacología , Esparcimiento de Virus/efectos de los fármacos , Esparcimiento de Virus/inmunología
11.
Br J Cancer ; 95(3): 406-15, 2006 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-16832408

RESUMEN

Despite declining incidence rates, gastric cancer (GC) is a major cause of death worldwide. Its aetiology may involve dietary antioxidant micronutrients such as carotenoids and tocopherols. The objective of this study was to determine the association of plasma levels of seven common carotenoids, their total plasma concentration, retinol and alpha- and gamma-tocopherol, with the risk of gastric adenocarcinoma in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), a large cohort involving 10 countries. A secondary objective was to determine the association of total sum of carotenoids, retinol and alpha-tocopherol on GCs by anatomical subsite (cardia/noncardia) and histological subtype (diffuse/intestinal). Analytes were measured by high-performance liquid chromatography in prediagnostic plasma from 244 GC cases and 645 controls matched by age, gender, study centre and date of blood donation. Conditional logistic regression models adjusted by body mass index, total energy intake, smoking and Helicobacter pylori infection status were used to estimate relative cancer risks. After an average 3.2 years of follow-up, a negative association with GC risk was observed in the highest vs the lowest quartiles of plasma beta-cryptoxanthin (odds ratio (OR) = 0.53, 95% confidence intervals (CI) = 0.30-0.94, P(trend) = 0.006), zeaxanthin (OR = 0.39, 95% CI = 0.22-0.69, P(trend) = 0.005), retinol (OR = 0.55, 95% CI = 0.33-0.93, P(trend) = 0.005) and lipid-unadjusted alpha-tocopherol (OR = 0.59, 95% CI = 0.37-0.94, P(trend) = 0.022). For all analytes, no heterogeneity of risk estimates or significant associations were observed by anatomical subsite. In the diffuse histological subtype, an inverse association was observed with the highest vs lowest quartile of lipid-unadjusted alpha-tocopherol (OR = 0.26, 95% CI = 0.11-0.65, P(trend) = 0.003). These results show that higher plasma concentrations of some carotenoids, retinol and alpha-tocopherol are associated with reduced risk of GC.


Asunto(s)
Adenocarcinoma/epidemiología , Carotenoides/administración & dosificación , Dieta , Neoplasias Gástricas/epidemiología , Tocoferoles/administración & dosificación , Vitamina A/administración & dosificación , Adenocarcinoma/sangre , Adenocarcinoma/diagnóstico , Adulto , Anciano , Carotenoides/sangre , Estudios de Casos y Controles , Europa (Continente)/epidemiología , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Fenómenos Fisiológicos de la Nutrición , Estudios Prospectivos , Factores de Riesgo , Neoplasias Gástricas/sangre , Neoplasias Gástricas/diagnóstico , Tocoferoles/sangre , Vitamina A/sangre
13.
Am J Gastroenterol ; 100(9): 1941-8, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16128937

RESUMEN

OBJECTIVES: Host genetic factors, including the IL1 gene cluster, play a key role in determining the long-term outcome of Helicobacter pylori infection. The aim of the study was to investigate the relationship between selected IL1 loci polymorphisms and gastric cancer risk in an Italian population. METHODS: In a case-control study we compared the IL1B-31 and IL1B+3954 biallelic and IL1RN pentaallelic variable number of tandem repeats (VNTR) polymorphisms in 185 gastric cancer patients and 546 controls randomly sampled from the general population of an area at high gastric cancer risk (Tuscany, Central Italy). RESULTS: Genotype frequencies of the IL1B-31 T/C, IL1B+3954 C/T, and IL1RN polymorphisms among our population controls were in Hardy-Weinberg equilibrium. In multivariate analyses, no increase in gastric cancer risk was observed for the IL1B-31*C- and IL1B+3954*T- carriers; a significant 50% increase emerged for IL1RN*2 allele carriers (OR = 1.49; 95% CI: 1.01-2.21). Analyses based on combined genotypes showed also that the association with IL1RN*2 allele was limited to two-variant allele carriers who were also homozygous for the IL1B-31*T allele (OR = 2.23; 95% CI: 1.18-4.23) with a statistically significant interaction between these two genotypes (p= 0.043). Haplotype analysis showed an increased risk for the haplotype IL1RN*2/IL1B-31*T. CONCLUSIONS: Our results suggest that host genetic factors (such as the IL1RN and the IL1B-31 polymorphisms) interact in the complex process of gastric carcinogenesis in this high-risk Italian population. Overall, this effect appears more modest than previously reported in other populations, supporting the hypothesis that other still-to-be-defined factors are important in gastric carcinogenesis. These findings might be due to a haplotype effect.


Asunto(s)
Interleucina-1/genética , Polimorfismo Genético , Neoplasias Gástricas/genética , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Genotipo , Haplotipos , Heterocigoto , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Secuencias Repetidas en Tándem
15.
J Viral Hepat ; 10(6): 455-9, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14633180

RESUMEN

Mixed cryoglobulinaemia, when not secondary to other well-defined immunological disorders, is commonly associated with hepatitis C virus (HCV) infection. However, a minority of cases lack evidence of HCV infection and are, therefore, defined as 'true essential' mixed cryoglobulinaemias. We thoroughly investigated three such patients to determine the aetiology of this disorder. Antibodies to HCV (anti-HCV) and HCV RNA, detected by sensitive enzyme-linked immunosorbent and polymerase chain reaction assays in serum and in concentrated cryoglobulins, were repeatedly negative in the three patients. Despite the lack of evidence for HCV infection, two of them were still treated with interferon alpha-2a assuming unrecognized viral infection. Both patients demonstrated excellent clinical and laboratory responses, but cryoglobulinaemia relapsed after the withdrawal of therapy. At the time of relapse, HCV RNA genomic sequences were detected for the first time in the cryoprecipitates of both patients. In the third case, HCV RNA was demonstrated for the first time during a flare of cryoglobulinaemia coincident with varicella infection. In all three patients anti-HCV antibodies remained negative throughout follow-up. We conclude that some apparently 'essential' forms of mixed cryoglobulinaemia can be caused by occult HCV infection. Interferon therapy can be taken into consideration in such HCV-negative cases.


Asunto(s)
Crioglobulinemia/tratamiento farmacológico , Crioglobulinemia/etiología , Hepatitis C/complicaciones , Adulto , Antivirales/farmacología , Antivirales/uso terapéutico , Femenino , Anticuerpos contra la Hepatitis C/sangre , Humanos , Interferón alfa-2 , Interferón-alfa/farmacología , Interferón-alfa/uso terapéutico , Persona de Mediana Edad , ARN Viral/sangre , Proteínas Recombinantes
16.
Infect Immun ; 70(9): 4785-90, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12183520

RESUMEN

Most vaccines are still given parenterally. Mucosal vaccination would offer different advantages over parenteral immunization, including blocking of the pathogens at the portal of entry. In this paper, nontoxic Escherichia coli heat-labile enterotoxin (LT) mutants and Supramolecular Biovector systems (SMBV) were evaluated in mice as mucosal adjuvants and delivery systems, respectively, for intranasal immunization with the conjugated group C meningococcal vaccine. The conjugated vaccine formulated together with the LT mutants and the SMBV induced very high titers of serum and mucosal antibodies specific for the group C meningococcal polysaccharide. This vaccination strategy also induced high titers of antibodies with bactericidal activity, which is known to correlate with efficacy. Importantly, the mucosal vaccination, but not the conventional parenteral vaccination, induced bactericidal antibodies at the mucosal level. These data strongly support the feasibility of development of intranasal vaccines with an enhanced protective efficacy against meningococci and possibly against other encapsulated bacteria.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Toxinas Bacterianas/administración & dosificación , Enterotoxinas/administración & dosificación , Proteínas de Escherichia coli , Vacunas Meningococicas/administración & dosificación , Administración Intranasal , Animales , Anticuerpos Antibacterianos/biosíntesis , Anticuerpos Antibacterianos/sangre , Toxinas Bacterianas/genética , Enterotoxinas/genética , Escherichia coli/genética , Escherichia coli/inmunología , Femenino , Humanos , Inmunidad Mucosa , Ratones , Ratones Endogámicos BALB C , Mutación , Neisseria meningitidis/inmunología , Vacunas Conjugadas/administración & dosificación
17.
FEBS Lett ; 508(3): 479-83, 2001 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-11728476

RESUMEN

The protein vacuolating toxin A (VacA) of Helicobacter pylori converts late endosomes into large vacuoles in the presence of permeant bases. Here it is shown that this phenomenon corresponds to an accumulation of permeant bases and Cl(-) in HeLa cells and requires the presence of extracellular Cl(-). The net influx of Cl(-) is due to electroneutral, Na(+), K(+), 2Cl(-) cotransporter-mediated transport. Cell vacuolation leads to cell volume increase, consistent with water flux into the cell, while hyper-osmotic media decreased vacuole formation. These data represent the first evidence that VacA-treated cells undergo an osmotic unbalance, reinforcing the hypothesis that the VacA chloride channel is responsible for cell vacuolation.


Asunto(s)
Proteínas Bacterianas/toxicidad , Cloruros/metabolismo , Helicobacter pylori , Vacuolas/metabolismo , Agua/metabolismo , Cloruro de Amonio/farmacología , Proteínas Bacterianas/metabolismo , Bumetanida/farmacología , Permeabilidad de la Membrana Celular , Tamaño de la Célula , Endosomas/metabolismo , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Metilaminas/metabolismo , Presión Osmótica , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico , Simportadores de Cloruro de Sodio-Potasio/metabolismo , Vacuolas/efectos de los fármacos
18.
Eur J Immunol ; 31(12): 3816-24, 2001 12.
Artículo en Inglés | MEDLINE | ID: mdl-11745403

RESUMEN

The age-related and T cell-independent immunological properties of most capsular polysaccharides limit their use as vaccines, especially in children under 2 years of age. To overcome these limitations, polysaccharide antigens have been successfully conjugated to a variety of carrier proteins, such as diphtheria toxoid or tetanus toxoid (TT) and the diphtheria mutant (CRM197) to produce very successful glycoconjugate vaccines. The increasing demand for new conjugate vaccines requires the availability of additional carriers providing high and long-lasting T helper cell immunity. Here we describe the design and construction of three recombinant carrier proteins (N6, N10, N19) constituted by strings of 6, 10 or 19 human CD4(+) T cell epitopes from various pathogen-derived antigens, including TT and proteins from Plasmodium falciparum, influenza virus and hepatitis B virus. Each of these epitopes is defined as universal in that it binds to many human MHC class II molecules. When conjugated to Haemophilus influenzae type b (Hib) oligosaccharide, these carriers elicit a potent anti-Hib antibody response in mice. In the case of the N19-Hib conjugate, this response is at least as good as that observed with CRM197-Hib, a conjugate vaccine currently used for mass immunization. We also show that some of the universal epitopes constituting the recombinant carriers are specifically recognized by two human in vitro systems, suggesting that T cell memory is provided by the selected epitopes. The data indicate that rationally designed recombinant polyepitope proteins represent excellent candidates for the development and clinical testing of new conjugate vaccines.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Epítopos de Linfocito T , Vacunas contra Haemophilus/inmunología , Polisacáridos Bacterianos/inmunología , Vacunas Sintéticas/inmunología , Secuencia de Aminoácidos , Animales , Cápsulas Bacterianas , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Vacunas Conjugadas/inmunología
19.
Vaccine ; 20 Suppl 1: S38-41, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11587808

RESUMEN

Vaccines developed traditionally following empirical approaches have often limited problems of immunogenicity, probably due to the low level of purity of the active component(s) they contain. The application of new technologies to vaccine development is leading to the production of purer (e.g. recombinant) antigens which, however, tend to have a poorer immunogenicity as compared to vaccines of the previous generation. The search for new vaccine adjuvants involves issues related to their potential limits. Since the introduction of aluminium salts as vaccine adjuvants more than 70 years ago, only one adjuvant has been licensed for human use. The development of some of these new vaccine adjuvants has been hampered by their inacceptable reactogenicity. In addition, some adjuvants work strongly with some antigens but not with others, thus, limiting their potentially widespread use. The need to deliver vaccines via alternative routes of administration (e.g. the mucosal routes) in order to enhance their efficacy and compliance has set new requirements in basic and applied research to evaluate their efficacy and safety. Cholera toxin (CT) and labile enterotoxin (LT) mutants given along with intranasal or oral vaccines are strong candidates as mucosal adjuvants. Their potential reactogenicity is still matter of discussions, although available data support the notion that the effects due to their binding to the cells and those due to the enzymatic activity can be kept separated. Finally, adjuvanticity is more often evaluated in terms of antigen-specific antibody titers induced after parenteral immunization. It is known that, in many instances, antigen-specific antibody titers do not correlate with protection. In addition, very little is known on parameters of cell-mediated immunity which could be considered as surrogates of protection. Tailoring of new adjuvants for the development of vaccines with improved immunogenicity/efficacy and reduced reactogenicity will represent one of the major challenges of the ongoing vaccine-oriented research.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Vacunas/inmunología , Animales , Humanos , Inmunización , Modelos Animales
20.
Nutr Cancer ; 39(1): 42-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11588901

RESUMEN

Several N-nitroso compounds, present in foods and beverages or formed in the stomach from their precursors, act as alkylating agents. By using a highly reliable technique (high-resolution gas chromatography-mass spectrometry with negative-ion chemical ionization and selected ion recording), we measured a series of specific O6-alkylguanines in snap-frozen paired stomach tissue samples (tumor and noninvolved mucosa) obtained at surgery from 24 gastric cancer patients identified in Florence, Italy. Samples of noninvolved mucosa had higher levels of total O6-alkylguanines and more frequently detectable levels (54%) than tumor samples (29.2%). O6-propylguanine and O6-methylguanine were the single adducts most frequently detected in noninvolved mucosa and tumor tissue, respectively. Tumor samples showed higher levels of total O6-alkylguanines in female patients (p = 0.03) and among those with a diffuse histological type (p = 0.06) or seronegative for Helicobacter pylori CagA antibodies (p = 0.06). Mean dietary nitrate intake was significantly higher in patients with detectable levels of adducts in tumor samples (p = 0.03). Estimated intakes of dimethylamine and N-nitrosodimethylamine correlated with total levels of O6-alkylguanines in noninvolved gastric mucosa. These findings, although based on a small series of cases, support a role for N-nitroso compounds from dietary sources in the etiology of gastric cancer.


Asunto(s)
Aductos de ADN/análisis , Mucosa Gástrica/química , Guanina/análisis , Compuestos Nitrosos/análisis , Neoplasias Gástricas/química , Anciano , Anticuerpos Antibacterianos/sangre , Dieta , Dimetilaminas/análisis , Dimetilnitrosamina/análisis , Femenino , Análisis de los Alimentos , Cromatografía de Gases y Espectrometría de Masas , Jugo Gástrico/química , Mucosa Gástrica/patología , Helicobacter pylori/inmunología , Helicobacter pylori/patogenicidad , Humanos , Masculino , Persona de Mediana Edad , Compuestos Nitrosos/efectos adversos , Neoplasias Gástricas/etiología , Encuestas y Cuestionarios
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