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1.
Clin Exp Immunol ; 181(2): 219-29, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25880879

RESUMEN

The aim of this study was to elucidate more clearly the role of interleukin (IL)-18 in modulating the IL-22 pathway in primary Sjögren's syndrome (pSS) patients and in pSS-associated lymphomas. Minor salivary glands (MSGs) from patients with pSS and non-specific chronic sialoadenitis (nSCS), parotid glands biopsies from non-Hodgkin lymphomas (NHL) developed in pSS patients, were evaluated for IL-18, IL-22, IL-22 receptor 1 (IL-22R1), IL-22 binding protein (IL-22BP) and signal transducer and activator of transcription-3 (STAT-3) expression. MSGs IL-22R1-expressing cells were characterized by confocal microscopy and flow cytometry in pSS, nSCS and healthy controls . The effect of recombinant IL-18 and IL-22 on peripheral blood mononuclear cells (PBMCs) from pSS and nSCS was studied by flow cytometry and reverse transcription-polymerase chain reaction (RT-PCR). MSGs of pSS and NHL were characterized by an imbalance between IL-22 and IL-22BP protein expression, with IL-18 and IL-22BP being expressed in a mutually exclusive manner and IL-18 and IL-22R1 being correlated directly. Aberrant expression of IL-22R1, induced by IL-18, was observed only among tissue and circulating myeloid cells of pSS patients and macrophages of NHL tissues of pSS patients, but not nSCS. IL-22R1 expression on PBMC of pSS was functional, as its stimulation with recombinant IL-22 significantly up-regulated the expression of STAT-3, IL-17 and IL-22. An IL-18-dependent aberrant expression of IL-22R1 on cells of haematopoietic origin seems to be a specific immunological signature of patients with pSS and pSS-associated lymphomas.


Asunto(s)
Interleucina-18/inmunología , Linfoma no Hodgkin/inmunología , Receptores de Interleucina/inmunología , Sialadenitis/inmunología , Síndrome de Sjögren/inmunología , Adulto , Anciano , Femenino , Regulación de la Expresión Génica , Humanos , Interleucina-17/genética , Interleucina-17/inmunología , Interleucina-18/farmacología , Interleucinas/inmunología , Interleucinas/farmacología , Aparato Lagrimal/inmunología , Aparato Lagrimal/patología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/patología , Linfoma no Hodgkin/genética , Linfoma no Hodgkin/patología , Macrófagos/inmunología , Macrófagos/patología , Masculino , Persona de Mediana Edad , Células Mieloides/inmunología , Células Mieloides/patología , Cultivo Primario de Células , Receptores de Interleucina/genética , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/inmunología , Glándulas Salivales/inmunología , Glándulas Salivales/patología , Sialadenitis/genética , Sialadenitis/patología , Transducción de Señal , Síndrome de Sjögren/genética , Síndrome de Sjögren/patología , Interleucina-22
2.
People Nat (Hoboken) ; 4(1): 32-43, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35450207

RESUMEN

1. Many infectious pathogens spend a significant portion of their life cycles in the environment or in animal hosts, where ecological interactions with natural enemies may influence pathogen transmission to people. Yet, our understanding of natural enemy opportunities for human disease control is lacking, despite widespread uptake and success of natural enemy solutions for pest and parasite management in agriculture. 2. Here we explore three reasons why conserving, restoring, or augmenting specific natural enemies in the environment could offer a promising complement to conventional clinical strategies to fight environmentally mediated pathogens and parasites. (1) Natural enemies of human infections abound in nature, largely understudied and undiscovered. (2) Natural enemy solutions could provide ecological options for infectious disease control where conventional interventions are lacking. And, (3) Many natural enemy solutions could provide important co-benefits for conservation and human well-being. 3. We illustrate these three arguments with a broad set of examples whereby natural enemies of human infections have been used or proposed to curb human disease burden, with some clear successes. However, the evidence base for most proposed solutions is sparse, and many opportunities likely remain undiscovered, highlighting opportunities for future research.

3.
J Exp Med ; 192(11): 1645-52, 2000 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-11104806

RESUMEN

The generalized Shwartzman reaction in mice which had been primed and challenged with lipopolysaccharide (LPS) depends on interleukin (IL)-12-induced interferon (IFN)-gamma production at the priming stage. We examined the involvement in the priming mechanism of the unique population of Valpha14 natural killer T (NKT) cells because they promptly produce IFN-gamma after IL-12 stimulation. We report here that LPS- or IL-12-primed NKT cell genetically deficient mice were found to be resistant to LPS-elicited mortality. This outcome can be attributed to the reduction of IFN-gamma production, because injection of recombinant mouse IFN-gamma, but not injection of IL-12, effectively primed the NKT cell-deficient mice. However, priming with high doses of LPS caused mortality of severe combined immunodeficiency, NKT cell-deficient, and CD1-deficient mice, indicating a major contribution of NKT cells to the Shwartzman reaction elicited by low doses of LPS, whereas at higher doses of LPS NK cells play a prominent role. These results suggest that the numerically small NKT cell population of normal mice apparently plays a mandatory role in the priming stage of the generalized Shwartzman reaction.


Asunto(s)
Interleucina-12/sangre , Células Asesinas Naturales/inmunología , Fenómeno de Shwartzman/inmunología , Animales , Antígenos/inmunología , Antígenos de Superficie , Inmunidad Innata , Interferón gamma/sangre , Interferón gamma/inmunología , Interleucina-12/inmunología , Lectinas Tipo C , Lipopolisacáridos/inmunología , Depleción Linfocítica , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones SCID , Subfamilia B de Receptores Similares a Lectina de Células NK , Proteínas/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
4.
Sci Rep ; 10(1): 14227, 2020 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-32848179

RESUMEN

Climate change is expected to warm, deoxygenate, and acidify ocean waters. Global climate models (GCMs) predict future conditions at large spatial scales, and these predictions are then often used to parameterize laboratory experiments designed to assess biological and ecological responses to future change. However, nearshore ecosystems are affected by a range of physical processes such as tides, local winds, and surface and internal waves, causing local variability in conditions that often exceeds global climate models. Predictions of future climatic conditions at local scales, the most relevant to ecological responses, are largely lacking. To fill this critical gap, we developed a 2D implementation of the Regional Ocean Modeling System (ROMS) to downscale global climate predictions across all Representative Concentration Pathway (RCP) scenarios to smaller spatial scales, in this case the scale of a temperate reef in the northeastern Pacific. To assess the potential biological impacts of local climate variability, we then used the results from different climate scenarios to estimate how climate change may affect the survival, growth, and fertilization of a representative marine benthic invertebrate, the red abalone Haliotis rufescens, to a highly varying multi-stressor environment. We found that high frequency variability in temperature, dissolved oxygen (DO), and pH increases as pCO2 increases in the atmosphere. Extreme temperature and pH conditions are generally not expected until RCP 4.5 or greater, while frequent exposure to low DO is already occurring. In the nearshore environment simulation, strong RCP scenarios can affect red abalone growth as well as reduce fertilization during extreme conditions when compared to global scale simulations.

5.
Sci Rep ; 10(1): 5975, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32249775

RESUMEN

The first signs of sea star wasting disease (SSWD) epidemic occurred in just few months in 2013 along the entire North American Pacific coast. Disease dynamics did not manifest as the typical travelling wave of reaction-diffusion epidemiological model, suggesting that other environmental factors might have played some role. To help explore how external factors might trigger disease, we built a coupled oceanographic-epidemiological model and contrasted three hypotheses on the influence of temperature on disease transmission and pathogenicity. Models that linked mortality to sea surface temperature gave patterns more consistent with observed data on sea star wasting disease, which suggests that environmental stress could explain why some marine diseases seem to spread so fast and have region-wide impacts on host populations.


Asunto(s)
Enfermedades de los Animales/transmisión , Organismos Acuáticos , Enfermedades Transmisibles/veterinaria , Modelos Teóricos , Enfermedades de los Animales/epidemiología , Animales , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/transmisión , Brotes de Enfermedades , Oceanografía , Temperatura
6.
Mol Ecol ; 18(22): 4604-16, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19840264

RESUMEN

Positive correlations between individual genetic heterozygosity and fitness-related traits (HFCs) have been observed in organisms as diverse as plants, marine bivalves, fish or mammals. HFCs are not universal and the strength and stability of HFCs seem to be variable across species, populations and ages. We analysed the relationship between individual genetic variability and two different estimators of fitness in natural samples of European eel, growth rate (using back-calculated length-at-age 1, 2 and 3) and parasite infestation by the swimbladder nematode Anguillicola crassus. Despite using a large data set of 22 expressed sequence tags-derived microsatellite loci and a large sample size of 346 individuals, no heterozygote advantage was observed in terms of growth rate or parasite load. The lack of association was evidenced by (i) nonsignificant global HFCs, (ii) a Multivariate General Linear Model showing no effect of heterozygosity on fitness components, (iii) single-locus analysis showing a lower number of significant tests than the expected false discovery rate, (iv) sign tests showing only a significant departure from expectations at one component, and, (v) a random distribution of significant single-locus HFCs that was not consistent across fitness components or sampling sites. This contrasts with the positive association observed in farmed eels in a previous study using allozymes, which can be explained by the nature of the markers used, with the allozyme study including many loci involved in metabolic energy pathways, while the expressed sequence tags-linked microsatellites might be located in genes or in the proximity of genes uncoupled with metabolism/growth.


Asunto(s)
Anguilla/crecimiento & desarrollo , Anguilla/genética , Anguilla/parasitología , Aptitud Genética , Variación Genética , Animales , Etiquetas de Secuencia Expresada , Enfermedades de los Peces/parasitología , Genética de Población , Heterocigoto , Modelos Lineales , Repeticiones de Microsatélite , Nematodos
7.
Poult Sci ; 88(8): 1773-8, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19590094

RESUMEN

Specific antibodies are essential tools for studying proteins as well as for diagnostic research in biomedicine. The egg yolk of immunized chicken is an inexpensive source of high-quality polyclonal antibodies. The 12-kDa Parietaria judaica 2 allergen was expressed as a fusion protein and was used to immunize Leghorn chickens. In this paper, we show, using 2-dimensional gel electrophoresis and immunoblotting, that chicken antibodies raised against a recombinant allergen can be used to recognize similar proteins from a pollen raw extract. Allergen identity was confirmed by nanoLC-nanospray-tandem mass spectrometry analysis. Our data demonstrate for the first time that a synergistic combination of molecular biology, 2-dimensional PAGE, and use of nonmammalian antibodies represents a powerful tool for reliable identification of allergens.


Asunto(s)
Anticuerpos/inmunología , Antígenos de Plantas/inmunología , Pollos/inmunología , Yema de Huevo/metabolismo , Inmunoglobulinas/inmunología , Parietaria/química , Animales , Pollos/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Inmunoglobulinas/metabolismo , Parietaria/inmunología , Polen/inmunología
8.
J Fish Biol ; 74(9): 2178-86, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20735696

RESUMEN

Size selectivity of fyke nets for European eels Anguilla anguilla was investigated by reviewing the results of published experimental studies. A general size selectivity model was then derived that can be easily incorporated into demographic models to simulate population dynamics, assess and monitor abundance and length structure of eel stocks and forecast the consequences of different management options.


Asunto(s)
Anguilla/fisiología , Explotaciones Pesqueras/instrumentación , Modelos Teóricos , Animales , Tamaño Corporal , Dinámica Poblacional
9.
J Fish Biol ; 74(9): 2034-46, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20735687

RESUMEN

Anguilla anguilla glass eels arriving at two Mediterranean and two Atlantic sites were tested for differences in genetic composition between regions using a total of 23 microsatellite loci developed from an expressed sequence tag (EST) library. Hierarchical analysis of molecular variance indicated a non-significant difference between regions (Mediterranean v. Atlantic), which contrasted with the significant differences observed between samples within regions. The existence of a single spawning site for all A. anguilla individuals and extensive migration loop with great opportunity for mixing of individuals might explain the homogeneity in genetic composition found between regions. The observation of a (small-scale) pattern of genetic patchiness among intra-annual samples (arrival waves) within geographic regions does not conflict with the lack of (large-scale) geographic sub-structuring found between the Mediterranean and Atlantic regions, but most likely is a consequence of the strong dependence of A. anguilla on oceanic conditions in the Sargasso Sea that might result in a limited parental contribution to each spawning event. The comparison of Atlantic and Mediterranean A. anguilla glass eel recruits based on EST-linked microsatellite loci provides evidence supporting the hypothesis of panmixia A. anguilla across Europe.


Asunto(s)
Anguilla/genética , Etiquetas de Secuencia Expresada , Genética de Población , Repeticiones de Microsatélite , Alelos , Migración Animal , Animales , Océano Atlántico , Frecuencia de los Genes , Genotipo , Mar Mediterráneo , Modelos Estadísticos , Reproducción
10.
Mol Biol Cell ; 9(4): 715-31, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9529373

RESUMEN

The beta1-integrin cytoplasmic domain consists of a membrane proximal subdomain common to the four known isoforms ("common" region) and a distal subdomain specific for each isoform ("variable" region). To investigate in detail the role of these subdomains in integrin-dependent cellular functions, we used beta1A and beta1B isoforms as well as four mutants lacking the entire cytoplasmic domain (beta1TR), the variable region (beta1COM), or the common region (beta1 deltaCOM-B and beta1 deltaCOM-A). By expressing these constructs in Chinese hamster ovary and beta1 integrin-deficient GD25 cells (Wennerberg et al., J Cell Biol 132, 227-238, 1996), we show that beta1B, beta1COM, beta1 deltaCOM-B, and beta1 deltaCOM-A molecules are unable to support efficient cell adhesion to matrix proteins. On exposure to Mn++ ions, however, beta1B, but none of the mutants, can mediate cell adhesion, indicating specific functional properties of this isoform. Analysis of adhesive functions of transfected cells shows that beta1B interferes in a dominant negative manner with beta1A and beta3/beta5 integrins in cell spreading, focal adhesion formation, focal adhesion kinase tyrosine phosphorylation, and fibronectin matrix assembly. None of the beta1 mutants tested shows this property, indicating that the dominant negative effect depends on the specific combination of common and B subdomains, rather than from the absence of the A subdomain in the beta1B isoform.


Asunto(s)
Adhesión Celular/fisiología , Citoplasma/metabolismo , Integrina beta1/química , Integrina beta1/metabolismo , Actinina/metabolismo , Secuencia de Aminoácidos , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Sitios de Unión , Células CHO , Moléculas de Adhesión Celular/metabolismo , Cricetinae , Fibronectinas/metabolismo , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Integrina alfa5 , Integrina alfaV , Integrina beta1/genética , Integrina beta3 , Ratones , Datos de Secuencia Molecular , Mutación , Fosforilación , Glicoproteínas de Membrana Plaquetaria/metabolismo , Conformación Proteica , Proteínas Tirosina Quinasas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transducción de Señal , Talina/metabolismo
11.
Mol Biol Cell ; 12(10): 3126-38, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11598197

RESUMEN

There is increasing evidence that a fine-tuned integrin cross talk can generate a high degree of specificity in cell adhesion, suggesting that spatially and temporally coordinated expression and activation of integrins are more important for regulated cell adhesive functions than the intrinsic specificity of individual receptors. However, little is known concerning the molecular mechanisms of integrin cross talk. With the use of beta(1)-null GD25 cells ectopically expressing the beta(1)A integrin subunit, we provide evidence for the existence of a cross talk between beta(1) and alpha(V) integrins that affects the ratio of alpha(V)beta(3) and alpha(V)beta(5) integrin cell surface levels. In particular, we demonstrate that a down-regulation of alpha(V)beta(3) and an up-regulation of alpha(V)beta(5) occur as a consequence of beta(1)A expression. Moreover, with the use of GD25 cells expressing the integrin isoforms beta(1)B and beta(1)D, as well as two beta(1) cytoplasmic domain deletion mutants lacking either the entire cytoplasmic domain (beta(1)TR) or only its "variable" region (beta(1)COM), we show that the effects of beta(1) over alpha(V) integrins take place irrespective of the type of beta(1) isoform, but require the presence of the "common" region of the beta(1) cytoplasmic domain. In an attempt to establish the regulatory mechanism(s) whereby beta(1) integrins exert their trans-acting functions, we have found that the down-regulation of alpha(V)beta(3) is due to a decreased beta(3) subunit mRNA stability, whereas the up-regulation of alpha(V)beta(5) is mainly due to translational or posttranslational events. These findings provide the first evidence for an integrin cross talk based on the regulation of mRNA stability.


Asunto(s)
Antígenos CD/metabolismo , Cadenas beta de Integrinas , Integrina beta1/metabolismo , Integrinas/metabolismo , Glicoproteínas de Membrana Plaquetaria/metabolismo , Estabilidad del ARN/fisiología , ARN Mensajero/metabolismo , Receptores de Vitronectina/metabolismo , Animales , Antígenos de Superficie/metabolismo , Adhesión Celular/fisiología , Células Cultivadas/citología , Células Cultivadas/metabolismo , Citoplasma/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Integrina alfaV , Integrina beta3 , Integrinas/agonistas , Integrinas/efectos de los fármacos , Ratones , Estructura Terciaria de Proteína/fisiología , Receptores de Vitronectina/antagonistas & inhibidores , Fracciones Subcelulares/metabolismo , Regulación hacia Arriba/efectos de los fármacos
12.
Philos Trans R Soc Lond B Biol Sci ; 372(1722)2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28438917

RESUMEN

Reducing the burden of neglected tropical diseases (NTDs) is one of the key strategic targets advanced by the Sustainable Development Goals. Despite the unprecedented effort deployed for NTD elimination in the past decade, their control, mainly through drug administration, remains particularly challenging: persistent poverty and repeated exposure to pathogens embedded in the environment limit the efficacy of strategies focused exclusively on human treatment or medical care. Here, we present a simple modelling framework to illustrate the relative role of ecological and socio-economic drivers of environmentally transmitted parasites and pathogens. Through the analysis of system dynamics, we show that periodic drug treatments that lead to the elimination of directly transmitted diseases may fail to do so in the case of human pathogens with an environmental reservoir. Control of environmentally transmitted diseases can be more effective when human treatment is complemented with interventions targeting the environmental reservoir of the pathogen. We present mechanisms through which the environment can influence the dynamics of poverty via disease feedbacks. For illustration, we present the case studies of Buruli ulcer and schistosomiasis, two devastating waterborne NTDs for which control is particularly challenging.This article is part of the themed issue 'Conservation, biodiversity and infectious disease: scientific evidence and policy implications'.


Asunto(s)
Salud Global , Enfermedades Desatendidas/epidemiología , Enfermedades Desatendidas/prevención & control , Medicina Tropical , Conservación de los Recursos Naturales , Ambiente , Humanos , Enfermedades Desatendidas/etiología , Pobreza
13.
Biochim Biophys Acta ; 494(1): 1-8, 1977 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-20151

RESUMEN

Perinereis erythrocruorin has the following physicochemical properties: So20,w = 55S, corresponding to a molecular weight around 2.7-10(6); minimum molecular weight (on the basis of the heme content) 23 700 +/- 500; isoelectric point 5.1; alpha-helix content approximately 40%. At alkaline pH values in the oxygenated form the 55-S molecules dissociate into subunits with a weight average sedimentation coefficient of 3S, corresponding to a molecular weight approximately 35 000. Deoxygenation of partially dissociated samples promotes association of the 3-S subunits into a 9S component. The functional properties of Perinereis erythrocruorin are characterized by a low cooperativity in oxygen binding (n 1/2 = 1.5) at neutral pH. Cooperativity increases reversibly towards both the acid and alkaline pH range, irrespective of changes in molecular weight. This finding, taken together with the ultracentrifuge results, suggests that a subunit may represent the functional unit of the protein. The pH dependence of the oxygen affinity can be accounted for in terms of a single oxygen linked group with a pK of 8.


Asunto(s)
Eritrocruorinas/metabolismo , Hemoglobinas/metabolismo , Sitio Alostérico , Anélidos , Monóxido de Carbono/metabolismo , Cationes Bivalentes , Dicroismo Circular , Concentración de Iones de Hidrógeno , Microscopía Electrónica , Oxígeno/metabolismo , Análisis Espectral , Ultracentrifugación
14.
Hum Immunol ; 62(9): 871-84, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11543889

RESUMEN

Y-chromosome variation was analyzed in a sample of 1127 males from the Western Mediterranean area by surveying 16 biallelic and 4 multiallelic sites. Some populations from Northeastern Europe and the Middle East were also studied for comparison. All Y-chromosome haplotypes were included in a parsimonious genealogic tree consisting of 17 haplogroups, several of which displayed distinct geographic specificities. One of the haplogroups, HG9.2, has some features that are compatible with a spread into Europe from the Near East during the Neolithic period. However, the current distribution of this haplogroup would suggest that the Neolithic gene pool had a major impact in the eastern and central part of the Mediterranean basin, but very limited consequences in Iberia and Northwestern Europe. Two other haplogroups, HG25.2 and HG2.2, were found to have much more restricted geographic distributions. The first most likely originated in the Berbers within the last few thousand years, and allows the detection of gene flow to Iberia and Southern Europe. The latter haplogroup is common only in Sardinia, which confirms the genetic peculiarity and isolation of the Sardinians. Overall, this study demonstrates that the dissection of Y-chromosome variation into haplogroups with a more restricted geographic distribution can reveal important differences even between populations that live at short distances, and provides new clues to their past interactions.


Asunto(s)
Variación Genética , Polimorfismo Genético , Cromosoma Y/genética , África del Norte , Alelos , Europa (Continente) , Haplotipos/genética , Humanos , Masculino , Región Mediterránea , Repeticiones de Microsatélite , Medio Oriente , Análisis Multivariante , Recombinación Genética
15.
Ann N Y Acad Sci ; 1007: 117-28, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14993046

RESUMEN

Steroids may have a powerful role in neuronal degeneration. Recent research has revealed that steroids may influence the onset and progression of some retinal disorders as well as neurodegenerative diseases and, as in brain, they accumulate in the retina via a local synthesis (neurosteroids) and metabolism of blood-circulating steroid hormones. Their crucial role as neurodegenerative and neuroprotective agents has been also upheld in a retinal excitotoxic paradigm. These findings are reviewed especially from the emerging perspective that after an insult local changes in steroidogenic responses and consequent neurosteroid availability might turn out to be offensive or defensive cellular adaptations for the potentiation or prevention of neuronal death.


Asunto(s)
Enfermedades Neurodegenerativas/metabolismo , Fármacos Neuroprotectores/metabolismo , Degeneración Retiniana/metabolismo , Esteroides/metabolismo , Animales , Humanos , Receptores de Superficie Celular/metabolismo
16.
Clin Ther ; 7(6): 680-3, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2934134

RESUMEN

Eight neonates and three young children at risk for hepatitis B infection were vaccinated with minimal doses of inactivated hepatitis B vaccine. The purpose of the study was to evaluate the efficacy of low doses with a view toward reducing the cost of immunization and therefore extending the practice to a larger number of subjects and minimizing the incidence of adverse reactions to the vaccine. The patients received two intramuscular injections (0.1 ml) of vaccine at a two-month interval and a booster six months after the first dose. Anti-HBs titers were determined simultaneously by radioimmunoassay on all serum samples collected. Five of the 11 patients achieved presumably protective (greater than 10 mU/ml) antibody levels within six months after the first dose (titers between 10 and 74 mU/ml), and all but one patient achieved titers between 27 and 2,500 mU/ml within two months after the booster. No adverse reaction was observed.


Asunto(s)
Anticuerpos contra la Hepatitis B/análisis , Hepatitis B/prevención & control , Recién Nacido , Vacunas contra Hepatitis Viral/administración & dosificación , Preescolar , Vacunas contra Hepatitis B , Humanos , Lactante , Radioinmunoensayo , Vacunación , Vacunas contra Hepatitis Viral/inmunología
17.
J Chromatogr A ; 828(1-2): 397-400, 1998 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-9916320

RESUMEN

Hyperhomocysteinemia is an independent risk factor for atherosclerosis and vascular occlusive disease. Assessment of total plasma concentration of homocysteine (tHcys) requires accurate and reproducible measurements. The aim of this study was to test a rapid isocratic HPLC method for tHcys analysis with an internal standard (I.S.) of alpha-mercaptopropionylglycine (MPG), 2-mercaptoethylamine (ME), or N-acetylcysteine (NAC) or without I.S., and to verify whether the use of an I.S. improves the precision. The method without I.S. showed an excellent linearity (y = 1.59x - 0.15, r = 1), recovery (100%) and a within-assay relative standard deviation (R.S.D.) of 1.2%. Instead, in our hands, the presence of I.S.s decreased the reproducibility (within-assay R.S.D. ranged from 4.5 to 6.5%) and lengthened the chromatogram by up to four to five times. In conclusion, HPLC measurement of plasma tHcys without I.S. improves accuracy with respect to determination with I.S.; moreover, this approach allows to routinely process larger amounts of plasma samples.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Homocisteína/sangre , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia
18.
J Chromatogr A ; 896(1-2): 183-9, 2000 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-11093653

RESUMEN

Homocystinuria, due to a deficiency of cystationine-beta-synthase, refers to the rare inborn error of the metabolism of homocysteine. The identification and prompt treatment of homocystinuria during the neonatal period can prevent or greatly reduce the severity of the clinical consequences. We report a new method for homocystinuria diagnosis from dried blood spots on newborn screening cards, based on high-performance liquid chromatography with electrochemical coulometric array detection. This method shows an excellent linearity (y=10.36x+0.04; r=0.999), precision (RSDs ranged from 2.7 to 5.8%), recovery (87%) and appears to be a cost-effective approach, being simple, rapid, sensitive and cheap.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Homocisteína/sangre , Electroquímica , Humanos , Recién Nacido , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Anticancer Res ; 20(6B): 4347-50, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11205269

RESUMEN

Structural changes in the macromolecular targets of pharmacological agents can result in alterations in the efficacy of these agents. In previous studies Berger et al. (1) identified a variant structural form of thymidylate synthase (TS) that is associated with relative resistance to 5-fluoro-2'-deoxyuridine, in a human colonic tumor cell line. They observed that expression of the variant TS, which differs from the normal form by a tyrosine to histidine substitution at residue 33, confers a 4-fold level of drug resistance in mammalian cells, as well as in bacteria. Now we report on the use of RT-PCR techniques to see if that variant TS form could be present in human samples from patients who underwent surgery for primary colorectal cancer and been previously untreated and to try to find relationships between that hypothetical variant TS form and the 5-Fluorouracil treatment. The possible role of Tyr-33 in 5-fluoropyrimidine-mediated inhibition of TS is discussed.


Asunto(s)
Neoplasias del Colon/genética , Proteínas de Neoplasias/genética , Mutación Puntual , Neoplasias del Recto/genética , Timidilato Sintasa/genética , Adenocarcinoma/enzimología , Adenocarcinoma/genética , Adenocarcinoma/patología , Anciano , Neoplasias del Colon/enzimología , Neoplasias del Colon/patología , Femenino , Histidina , Humanos , Masculino , Estadificación de Neoplasias , Neoplasias del Recto/enzimología , Neoplasias del Recto/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tirosina
20.
J Pharm Biomed Anal ; 24(5-6): 1137-41, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11248510

RESUMEN

Total plasma homocysteine (tHcy) in children may be an useful biochemical marker for genetic risk of premature cardiovascular disease. We reported a rapid, isocratic HPLC method able to process very small amount of newborn plasma samples. A blood sample from heel capillary circulation was collected, using a heparinized capillary glass tube. Plasma sample from 1 to 10 microl was derivatized with ammonium-7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate after reduction with tri-n-butylphosphine and analyzed on Discovery C18 column, with a solution of acetonitrile-dihydrogenphosphate 0.1 M (8:92 v/v pH*2.1). This assay ensures a good recovery (95%), precision (CV 4.5%) and linearity (y=2.41x + 0.31, r=1). Due to its simplicity and reliability, our method is suitable for routine analysis of tHcy and other aminothiols (Cys, Cys-Gly, GSH) assessed for clinical and research purposes. With this HPLC method we have assayed tHcy levels in 1400 apparently healthy newborn babies (tHcy mean value=4.9+/-2.7 microM). In conclusion, this accurate and linear HPLC method allows measurement of tHcy in newborn during the routinary capillary blood collection in the fourth living day without any other invasive procedure.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Homocisteína/sangre , Avitaminosis/sangre , Avitaminosis/diagnóstico , Femenino , Colorantes Fluorescentes/química , Humanos , Hiperhomocisteinemia/sangre , Hiperhomocisteinemia/diagnóstico , Recién Nacido , Masculino , Tamizaje Neonatal , Oxadiazoles/química , Reproducibilidad de los Resultados
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