RESUMEN
BACKGROUND: Camelina sativa oil is one of the richest dietary sources of omega-3, with polyunsaturated fatty acids amounts of over 50%, linolenic acid content of around 40-45%, and linoleic acid of about 15%. Moreover, this oil is a valuable source of antioxidants which provide oxidative stability. All those features raise interest in considering Camelina oil as an alternative and sustainable oil source providing stable omega-3-rich emulsions for functional food production. OBJECTIVES: The present study aimed to investigate the effects of Camelina oil-enriched crackers on serum omega-3 concentration, inflammatory markers and serum lipid profile. DESIGN: Randomized placebo-controlled pilot trial. SETTING: Research and Development Center (Complife Italia s.r.l.). PARTICIPANTS: Sixty-six free-living older volunteers (aged≥65 years). INTERVENTION: Older adults were enrolled and randomly assigned to one of two groups: the camelina group or the placebo group. Subjects consumed daily 35 g of crackers (Camelina enriched crackers or placebo ones) twice daily for 12 weeks. MEASUREMENTS: Serum polyunsaturated fatty acid profile, inflammatory status and serum lipid panel parameters were recorded pre and post-intervention. RESULTS: In the camelina group, alpha-linolenic acid serum concentration was significantly higher (p<0.01) compared to the placebo group at the end of the study. Concerning inflammatory plasma markers, a significant mean pro-inflammatory interleukin-18 plasma concentration decrease in the placebo group compared to the camelina one was observed (p<0.05). No significant differences in other mean inflammatory markers concentrations post-intervention were noted in either group. Lastly, examining the change in lipid profile, it is noteworthy that a higher reduction of total cholesterol, low-density lipoprotein and triglycerides in the camelina group post-intervention, despite the lack of statistical significance. CONCLUSION: Camelina oil significantly elevated the serum alpha-linolenic acid concentration with no significant changes in inflammatory markers and lipid profile.
Asunto(s)
Ácidos Grasos Omega-3 , Humanos , Anciano , Ácido alfa-Linolénico/farmacología , Proyectos Piloto , Ácidos Grasos Insaturados , TriglicéridosRESUMEN
En septiembre de 2006 se puso en funcionamiento en nuestro centro una nueva área de atención quirúrgica, integrada en el propio complejo hospitalario. Es una nueva estructuración de los espacios quirúrgicos que forma parte de la estrategia de la organización en su tarea de mejora continua en la atención al paciente. Se trata de un área de Cirugía Mayor Ambulatoria denominada Unidad de Cirugía sin Ingreso, y su gestión se ha estructurado en base a la gestión por procesos. Describiremos en este trabajo la metodología empleada para poner en marcha esta unidad y los pasos necesarios para el control de la mejora continua. Creemos que el desarrollo metodológico del subproceso de Unidad de Cirugía sin Ingreso ha sido muy satisfactorio, tanto en cuanto a la metodología aplicada, como por la experiencia del trabajo en equipo (AU)
In September 2006 our center started a new surgical care area, integrated in the hospital premises. As a new structuration of the surgical spaces, it is a part of the organizations strategy towards continuous improvement in patient care. It is a Major Ambulatory Surgery area known as Outpatient Surgery Unit, and its being managed under the methodology of process management. This paper describes the methodology used to set up this unit, and the necessary steps for monitoring continuous improvement. We believe that the methodological development of the Outpatient Surgery Unit subprocess has been very satisfactory, regarding both the applied methodology and the experience of teamwork (AU)
Asunto(s)
Humanos , Procedimientos Quirúrgicos Ambulatorios , Calidad de la Atención de Salud , Servicio de Cirugía en Hospital/organización & administración , Modelos Organizacionales , EspañaRESUMEN
High organochlorine concentrations have been found among the Inuit in eastern Canada and in Greenland. The present study was undertaken to assess the exposure to organochlorines in relation to age, sex, and diet in a general population sample of Inuit from Greenland. Survey data and plasma concentrations of 14 polychlorinated biphenyl (PCB) congeners and 16 pesticides, including 5 toxaphene congeners, were recorded in a random population survey of 408 adult indigenous Greenlanders. In a two-stage design, the survey response rate was 66%, and 90% of those randomly selected for blood testing participated. This was equivalent to an overall response rate of 59%. The median plasma concentration of the sum of PCB congeners was 13.3 microg/L; the lipid-adjusted value was 2109 microg/kg. The PCB concentration was twice as high as among the Inuit of Nunavik, Canada, 25 times higher than in a control group from southern Canada, and several times higher than the values found in European studies. Concentrations were similarly elevated for all PCB congeners and pesticides. The PCB congener pattern was similar to previous observations from the eastern Canadian Arctic and Greenland. Concentrations showed statistically significant positive associations with age, marine diet, and male sex in multiple linear regression analyses. The exceptionally high plasma concentrations of several organochlorines among the Inuit of Greenland are attributed to a lifelong high intake of seafood, in particular marine mammals. Concentrations of PCB adjusted for the consumption of marine food increased until approximately 40 yr of age, which is equivalent to the birth cohorts of the early 1950s. The age pattern indicates that bioaccumulation of PCB started in the 1950s, which is a likely date for the introduction of the compounds into the Arctic environment.
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Dieta , Exposición a Riesgos Ambientales/análisis , Conducta Alimentaria/etnología , Hidrocarburos Clorados , Insecticidas/análisis , Insecticidas/sangre , Inuk , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/sangre , Alimentos Marinos/análisis , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Canadá , Estudios de Casos y Controles , Dieta/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Femenino , Groenlandia , Encuestas Epidemiológicas , Humanos , Insecticidas/efectos adversos , Modelos Lineales , Masculino , Persona de Mediana Edad , Residuos de Plaguicidas/efectos adversos , Alimentos Marinos/efectos adversos , Distribución por Sexo , Encuestas y CuestionariosAsunto(s)
Medicina Legal , Examen Físico , Violación , Predominio Social , Salud de la Mujer , Derechos de la Mujer , Composición Familiar/etnología , Medicina Legal/economía , Medicina Legal/educación , Medicina Legal/historia , Medicina Legal/legislación & jurisprudencia , Ciencias Forenses/economía , Ciencias Forenses/educación , Ciencias Forenses/historia , Ciencias Forenses/legislación & jurisprudencia , Francia/etnología , Historia del Siglo XIX , Jurisprudencia/historia , Observación/métodos , Examen Físico/economía , Examen Físico/historia , Examen Físico/psicología , Violación/legislación & jurisprudencia , Violación/psicología , Obras Médicas de Referencia , Conducta Social , Libros de Texto como Asunto/historia , Violencia/etnología , Violencia/historia , Violencia/legislación & jurisprudencia , Violencia/psicología , Mujeres/educación , Mujeres/historia , Mujeres/psicología , Salud de la Mujer/economía , Salud de la Mujer/etnología , Salud de la Mujer/historia , Salud de la Mujer/legislación & jurisprudencia , Derechos de la Mujer/economía , Derechos de la Mujer/educación , Derechos de la Mujer/historia , Derechos de la Mujer/legislación & jurisprudenciaRESUMEN
PCB, p,p'-DDE, and mirex levels were examined in blood plasma samples of 232 anglers from Cornwall and Mississauga, Ontario, in a pilot study to establish the feasibility and suitability of using a cohort of Ontario fish license holders for large-scale health studies. Great Lakes fish, waterfowl, and ocean fish consumption were examined as predictors of contaminant levels using regression analysis, with adjustment for age, gender, and community. Levels of Great Lakes fish and waterfowl consumption and contaminant levels were generally low in comparison with those observed in other Great Lakes studies. However, even within these low levels, Great Lakes fish consumption was associated with increased blood plasma PCB levels in men and mirex levels in both men and women. Waterfowl consumption was associated with higher plasma PCB (men and women), DDE (men only), and mirex levels (men and Cornwall women), and requires further exploration. We conclude that other study designs are required (to identify high consumers) for carrying out studies of health effects associated with high levels of Great Lakes fish and waterfowl consumption.
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Diclorodifenil Dicloroetileno/sangre , Contaminantes Ambientales/sangre , Peces , Insecticidas/sangre , Mírex/sangre , Bifenilos Policlorados/sangre , Adulto , Animales , Estudios de Cohortes , Patos , Exposición a Riesgos Ambientales/análisis , Femenino , Explotaciones Pesqueras , Contaminación de Alimentos , Gansos , Great Lakes Region , Humanos , Masculino , Ontario , Proyectos Piloto , Salud Pública , Proyectos de Investigación , Medición de RiesgoRESUMEN
The goal of the study was to assess the contamination of marine algae (seaweeds) growing in the St. Lawrence River estuary and Gulf of St. Lawrence and to evaluate the risks to human health from the consumption of these algae. Algae were collected by hand at low tide. A total of 10 sites on the north and south shores of the St. Lawrence as well as in Baie des Chaleurs were sampled. The most frequently collected species of algae were Fucus vesiculosus, Ascophyllum nodosum, Laminaria longicruris, Palmaria palmata, Ulva lactuca, and Fucus distichus. Alga samples were analyzed for metals (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn), iodine, and organochlorines. A risk assessment was performed using risk factors (e.g., RfD of the U.S. EPA, ADI of Health Canada, etc.). In general, concentrations in St. Lawrence algae were not very high. This was especially true for mercury and the organochlorines, concentrations of which were very low or below detection limits. Consequently, health risks associated with these compounds in St. Lawrence algae were very low. Iodine concentration, on the other hand, could be of concern with regard to human health. Regular consumption of algae, especially of Laminaria sp., could result in levels of iodine sufficient to cause thyroid problems. For regular consumers, it would be preferable to choose species with low iodine concentrations, such as U. lactuca and P. palmata, in order to prevent potential problems. Furthermore, it would also be important to assess whether preparation for consumption or cooking affects the iodine content of algae. Algae consumption may also have beneficial health effects. Scientific literature has shown that it is a good source of fiber and vitamins, especially vitamin B12.
Asunto(s)
Eucariontes/química , Contaminación de Alimentos , Hidrocarburos Clorados , Insecticidas/análisis , Yodo/análisis , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Exposición a Riesgos Ambientales/análisis , Humanos , Quebec , Medición de RiesgoRESUMEN
Iron uptake analysis suggested that the Neisseria meningitidis transferrin (Tf) binding proteins, TbpA and TbpB, form only one type of receptor complex. Mutants defective in the synthesis of either TbpA or TbpB, but not defective in both proteins, can bind Tf, suggesting that both proteins are surface exposed and function in Tf binding. Also, iron uptake from Tf into the meningococci did not require the presence of both Tbps. The TbpB-defective mutant incorporated c. 37% of the iron taken up by the wild-type strain, but this was insufficient for bacterial growth. The TbpA-defective mutant incorporated c. 50% of the iron taken up by the wild-type strain and was able to grow with Tf as the only iron source. Mouse antibodies specific for TbpA were able to block c. 70% of the iron uptake from Tf in the wild-type strain, whereas they blocked only 22% of iron uptake in the TbpB-defective mutant and did not block uptake in the TbpA-defective strain. These results emphasise that TbpA should be considered in future vaccine trials in which iron-restricted proteins are to be included in the vaccine formulation.
Asunto(s)
Proteínas Portadoras/metabolismo , Hierro/metabolismo , Neisseria meningitidis/metabolismo , Receptores de Transferrina/metabolismo , Transferrina/metabolismo , Anticuerpos Bloqueadores/inmunología , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Regulación Bacteriana de la Expresión Génica , Humanos , Radioisótopos de Hierro , Proteínas de Unión a Hierro , Cinética , Mutación , Neisseria meningitidis/genética , Receptores de Transferrina/análisis , Proteínas de Unión a TransferrinaRESUMEN
OBJECTIVE: To compare mean concentrations of organochlorine in women with a new diagnosis of endometriosis and in controls. DESIGN: Case-control study. SETTING: Women attending an institutional clinic of reproductive endocrinology. PATIENT(S): Cases and controls were selected among women who underwent laparoscopy for chronic pelvic pain, infertility, or tubal fulguration between January 1994 and December 1994. Eighty-six women with endometriosis and 70 controls, matched for the indication for laparoscopy, were recruited. MAIN OUTCOME MEASURE(S): Mean organochlorine plasma concentrations of 14 polychlorinated biphenyl congeners and 11 chlorinated pesticides were compared between the cases and controls. Analysis of covariance was used to adjust means for confounding variables, and odds ratios were estimated by logistic regression. RESULT(S): Crude geometric mean concentrations did not differ significantly between cases and controls for any of the organochlorine compounds. Similarly, crude or adjusted means of the sum of polychlorinated biphenyl congeners, the sum of chlordanes, or the sum of dichlorodiphenyltrichloroethanes did not differ between the groups. There was no significant linear trend in the adjusted odds ratios for endometriosis as organochlorine concentrations increased. CONCLUSION(S): These results suggest that exposure to polychlorinated biphenyls and chlorinated pesticides during adulthood is not associated with endometriosis in the general population.
Asunto(s)
Endometriosis/etiología , Contaminantes Ambientales/sangre , Insecticidas/sangre , Residuos de Plaguicidas/sangre , Bifenilos Policlorados/sangre , Adulto , Estudios de Casos y Controles , Intervalos de Confianza , Endometriosis/fisiopatología , Contaminantes Ambientales/efectos adversos , Contaminantes Ambientales/clasificación , Femenino , Humanos , Insecticidas/efectos adversos , Insecticidas/clasificación , Modelos Logísticos , Persona de Mediana Edad , Oportunidad Relativa , Residuos de Plaguicidas/efectos adversos , Residuos de Plaguicidas/clasificación , Bifenilos Policlorados/efectos adversos , Bifenilos Policlorados/clasificación , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
The existence of epitopes common to different strains in the Neisseria meningitidis transferrin (Tf)-binding protein 2 (TBP2), combined with the ability of polyclonal anti-TBP2 antibodies to inhibit Tf binding and block iron uptake in this species, led to this study on the effect of anti-TBP1+2 monoclonal antibodies (MAbs) to determine the presence of epitopes inside the Tf-binding region. All MAbs used reacted exclusively with the homologous strain when tested by dot-blots of outer membrane vesicles, with the reaction being specific for TBP2 after SDS-PAGE and electroblotting. In contrast, ELISA and iron-uptake blocking assays were also positive with heterologous strains belonging to Rokbi's group II (high mol.wt TBP2). The results confirmed the two group classification proposed by Rokbi and, in contrast to other studies, indicated the existence of epitopes in the Tf-binding region that are common only to strains of Rokbi's group II. These epitopes may become denatured after drying for dot-blot assays or after SDS-PAGE and electroblotting.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Portadoras/inmunología , Hierro/metabolismo , Neisseria meningitidis/metabolismo , Animales , Proteínas de la Membrana Bacteriana Externa/metabolismo , Western Blotting , Proteínas Portadoras/metabolismo , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática , Humanos , Sueros Inmunes/inmunología , Immunoblotting , Proteínas de Unión a Hierro , Masculino , Neisseria meningitidis/inmunología , Conejos , Proteína B de Unión a Transferrina , Proteínas de Unión a TransferrinaRESUMEN
The 37 kDa iron-repressible protein, Fbp, was purified from two Neisseria meningitidis strains by metal-affinity chromatography and used to obtain mouse monospecific polyclonal immune sera. Dot-blot, immunoblotting and whole cell ELISA results demonstrate that the Fbp is present in all 16 N. meningitidis and four commensal Neisseria species tested, is highly antigenic in mouse when injected in pure form, and shows intra- and inter-species antigenic homogeneity, anti-Fbp antibodies being fully cross-reactive using the techniques mentioned. We also found that Fbp molecules (or parts of them) are surface exposed, in disagreement with the proposed exclusively periplasmic localization, although anti-Fbp antibodies seem unable to block iron uptake or to induce complement-mediated killing of the meningococci. Taken along with the high immunogenicity of the purified protein and the complete cross-reactivity of the antibodies elicited, this suggests that the protective effect of the purified Fbp must be further studied to evaluate its inclusion in future vaccine trials.
Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Reacciones Cruzadas , Neisseria meningitidis/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Proteínas de la Membrana Bacteriana Externa , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Humanos , Proteínas de Unión a Hierro , Ratones , Ratones Endogámicos BALB C , Microscopía Inmunoelectrónica , Proteínas de Unión PeriplasmáticasRESUMEN
Neisseria meningitidis, when cultured in iron-restricted environments, synthesises new outer-membrane proteins, many of which are necessary for their survival and growth. Some of these proteins e.g. transferrin-binding proteins 1 and 2 (Tbp1 and Tbp2), are required for the acquisition of iron from transferrin and are examples of important iron-regulated meningococcal surface antigens which are not expressed after growth in common laboratory media. The antigenicity and antigenic heterogeneity of these proteins have been extensively studied, and the bactericidal activity of antibodies directed to them have been studied. In this work we analysed the ability of such antibodies to inhibit transferrin binding and to block iron uptake from human transferrin. Antisera from mice immunized with either meningococcal outer membrane vesicles, purified Tbp1/2 complexes, or purified Tbp2, were incorporated in radiolabeled-iron uptake assays. Uptake was blocked by more than 80% in the homologous strains, but blocked much less efficiently in some heterologous strains, correlating well with inhibition of transferrin binding and with an inhibitory effect on bacterial growth. Inhibition of iron uptake from citrate was unaffected which suggests that this effect is due to antibodies against the components of the transferrin binding system, specially Tbp2. Our results support the importance of these proteins and their suitability to be considered in the development of effective vaccines against serogroup B meningococci.
Asunto(s)
Anticuerpos Bloqueadores/inmunología , Neisseria meningitidis/inmunología , Receptores de Transferrina/inmunología , Anticuerpos Antibacterianos/inmunología , Hierro/metabolismo , Microscopía Electrónica , Neisseria meningitidis/crecimiento & desarrollo , Neisseria meningitidis/metabolismo , Receptores de Transferrina/metabolismo , Transferrina/metabolismoRESUMEN
The lack of experimental models suitable for the study of meningococcal pathogenicity led us to investigate if those actually in use (culture in iron-restricted media and animal models) provide results comparable with the responses observed in vivo during infection. In this work we studied three invasive strains cultured both in laboratory media and in human plasma, analysing the immune responses elicited in mice against membrane antigens and comparing them with those seen using homologous human convalescent sera. Outer membrane protein profiles observed after culture in plasma were different and more complex than those obtained after growth in laboratory media. Analogous differences were observed in the antigenic profiles, detecting some antigens recognized by human, but not mouse sera, and vice versa. However, the response to one of the major iron-regulated outer membrane antigens, the transferrin binding protein 2 (TBP2), was unaffected by the culture medium or the model, human or mouse, used for the analysis. In conclusion, we have found that results of antigenic analysis change depending on the culture conditions and animal models used. For the meningococcal antigen TBP2, growth in iron-restricted laboratory media and a mouse model provide results which correlate well with those observed using convalescent human serum from individuals recovered from infections. We suggest that careful analysis and evaluation of experimental results and their comparison with in vivo elicited immune responses are essential in order to get accurate extrapolations for experimental vaccine designs.
Asunto(s)
Antígenos Bacterianos/análisis , Proteínas de la Membrana Bacteriana Externa/análisis , Proteínas Portadoras/análisis , Neisseria meningitidis/inmunología , Animales , Proteínas Portadoras/inmunología , Humanos , Proteínas de Unión a Hierro , Ratones , Peso Molecular , Proteína B de Unión a Transferrina , Proteínas de Unión a TransferrinaRESUMEN
When grown under iron restriction, Neisseria meningitidis expresses new outer-membrane proteins, some of which are antigenic and potentially useful as vaccine components. This is particularly relevant to N. meningitidis serogroup B, against which neither polysaccharide nor conjugate vaccines are effective. We investigated recognition of N. meningitidis serogroup B outer-membrane antigens by three sera from patients recovered from meningitis. Recognition of antigens from the homologous strain provided information on in vivo expression during infection and immunogenicity, while cross-reactivity with outer membrane proteins from the other two strains and from another five strains in our collection allowed evaluation of antigenic heterogeneity. Our results demonstrate that transferrin-binding protein 2 (TBP2) is immunogenic in humans, to varying degrees depending on the strain, and that TBP2s (like the equivalent proteins of Haemophilus influenzae type b) are among the most important iron-regulated outer membrane antigens expressed during infection. Other immunogenic outer membrane proteins (some iron-regulated) are also expressed during infection; in a previous study in mouse, three of these proteins (with M(r) of 50, 70 and 77 kDa) did not induce an immune response. Our cross-reactivity data provide some support for Robki et al.'s two-group classification of N. meningitidis strains, and provide evidence against the possibility that the antigenic domains shared by the TBP2s of all N. meningitidis strains induce immune responses in vivo.
Asunto(s)
Anticuerpos Antibacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Portadoras/inmunología , Neisseria meningitidis/inmunología , Animales , Líquido Cefalorraquídeo/microbiología , Reacciones Cruzadas , Humanos , Hierro/metabolismo , Proteínas de Unión a Hierro , Meningitis Meningocócica/sangre , Meningitis Meningocócica/líquido cefalorraquídeo , Meningitis Meningocócica/inmunología , Meningitis Meningocócica/microbiología , Ratones , Neisseria meningitidis/clasificación , Neisseria meningitidis/aislamiento & purificación , Serotipificación , Proteína B de Unión a Transferrina , Proteínas de Unión a TransferrinaRESUMEN
A method for purifying TBP2 from N. meningitidis has been developed using affinity chromatography on Tf-agarose followed by ion exchange chromatography; the Tf-binding activity of fractions was evaluated by a dot-blot technique. This method allowed the purification of the TBP2 in milder conditions than those used previously and to a high degree of homogeneity as was demonstrated by Coomassie brilliant blue or Silver staining after SDS-PAGE electrophoresis. The SDS-PAGE profile of the material obtained in the Tf-agarose affinity chromatography step shows only two detectable proteins, identified as the TBP1 and the TBP2, with a small amount of contamination. Passage through a MonoQ HR anion exchange column, allowed the isolation of TBP2 in the absence of TBP1. Our results demonstrate the conservation of the antigenic reactivity of this protein, which produces monospecific serum with the antibodies elicited reacting exclusively with the TBP2 in whole outer membrane vesicles.
Asunto(s)
Proteínas Portadoras/aislamiento & purificación , Hierro , Neisseria meningitidis/química , Transferrina , Proteínas Portadoras/metabolismo , Cromatografía de Afinidad , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Humanos , Proteínas de Unión a Hierro , Proteína B de Unión a Transferrina , Proteínas de Unión a TransferrinaRESUMEN
Growing Neisseria meningitidis on an iron restriction medium induces the synthesis of new outer membrane proteins, some of them true iron-regulated outer membrane proteins (IROMPs) and others synthesized because of the stress produced by the iron restriction. Some of these proteins are antigenic and can be considered for the development of vaccines; this is especially desirable in the case of N. meningitidis serogroup B, for which polysaccharide vaccines are not efficient. The antigenicity of N. meningitidis 37- and 70-kDa IROMPs has been studied previously; in this work, we studied the immunogenicity and antigenic heterogeneity of another IROMP, the human transferrin-binding protein 2 (TBP2), which seems to be indispensable for meningococcal growth inside the host. Mice were inoculated with purified outer membrane vesicles (blebs) from 5 selected N. meningitidis strains, and the five serum samples obtained were analyzed for anti-TBP2 antibodies by using the homologous strain and for cross-reactivity with the TBP2 of the 4 other selected strains and another 35 heterologous N. meningitidis strains. The TBP2s of the 5 strains tested were all immunogenic in mice to various degrees depending on the strain, and all five TBP2s shared one or more epitopes with heterologous strains (as shown by the cross-reactivities of the five serum samples), although the number of cross-reacting strains was very variable, ranging from 2 for strain V002 to 35 for strain P391. This suggests that the TBP2 epitopes of different strains differ in nature or in their accessibility to the immune system. Under the iron restriction conditions used, all strains synthesized a non-TBP2 antigenic 56-kDa protein thought to be a stress protein.
Asunto(s)
Proteínas Portadoras/inmunología , Neisseria meningitidis/patogenicidad , Animales , Antígenos Bacterianos/inmunología , Antígenos de Superficie/inmunología , Reacciones Cruzadas , Electroforesis en Gel de Poliacrilamida , Humanos , Immunoblotting , Hierro/metabolismo , Proteínas de Unión a Hierro , Ratones , Ratones Endogámicos BALB C , Proteína B de Unión a Transferrina , Proteínas de Unión a TransferrinaAsunto(s)
Vacunas Bacterianas , Neisseria meningitidis/inmunología , Animales , Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/clasificación , Vacunas Bacterianas/inmunología , Niño , Preescolar , Estudios de Evaluación como Asunto , Humanos , Meningitis Meningocócica/prevención & control , Vacunas Meningococicas , Ratones , Neisseria meningitidis/clasificación , Neisseria meningitidis/patogenicidad , Polisacáridos Bacterianos/inmunología , Toxoide Tetánico/inmunología , Vacunas Sintéticas , VirulenciaRESUMEN
Peroxidase-conjugated transferrin was used to detect transferrin receptors both in intact outer membrane vesicles (OMVs) from Neisseria species in a dot blot assay, and in SDS-PAGE-separated OMV proteins after transferring to nitrocellulose membranes. All N. meningitidis strains produced transferrin receptors after culturing in either iron sufficiency or iron restriction although expression was higher in the latter case, whereas only six N. lactamica and two N. sicca (among 20 commensal species) were able to bind transferrin. Molecular mass (MM) of the receptors were mainly between 78 kDa and 85 kDa (87.5% of strains), 12.5% had receptors with MM close to 70 kDa, and 5% showed receptors with MM over 85 kDa. Our results confirm the molecular mass heterogeneity of the transferrin receptors in N. meningitidis, completely disagree with the 'universal' 98 kDa receptor proposed by some authors, and show a low expression of the receptor in commensal Neisseria.
Asunto(s)
Neisseria meningitidis/química , Neisseria/química , Receptores de Transferrina/química , Densitometría , Electroforesis en Gel de Poliacrilamida , Humanos , Meningitis Meningocócica/microbiología , Receptores de Transferrina/metabolismo , TemperaturaRESUMEN
Capillary gas chromatography with nitrogen-specific detection allows rapid screening of numerous drugs of toxicological interest. However, for accurate identification of individual peaks, the system must be well calibrated, e.g., through the use of retention indices (RI). To overcome problems associated with the use of RI's based on homologous series determined with nitrogen-specific detectors, we have developed an RI reference system based on molecular masses and retention times of nitrogen-containing compounds. The standards chosen are easily available in highly purified form and can be detected by the unmodified nitrogen-specific detector. By using temperature programming, we can obtain a linear relationship between the molecular masses of standards and their retention times. Used in conjunction with microcomputer data handling, this screening system is rugged and reliable, operating 22 h per day. In the past two years, we have screened greater than 3000 samples (blood, serum, urine, gastric lavage) without major problems.
Asunto(s)
Cromatografía de Gases , Nitrógeno/análisis , Preparaciones Farmacéuticas/análisis , Toxicología/métodos , Humanos , Peso Molecular , Control de Calidad , Estándares de Referencia , TemperaturaRESUMEN
In Canada, 8% to 20% of infants are breast-fed by mothers who smoke. To determine whether breast-feeding increases infants' exposure to tobacco smoke products, urinary cotinine excretion was measured in 172 babies, 33 of whom were breast-fed. A milk sample was taken from the mothers who were breast-feeding, and cotinine was measured with gas chromatography. The breast-fed babies had a median cotinine to creatinine ratio of 433 ng/mg, whereas the bottle-fed babies' median was 200 ng/mg (P less than 10(-4)). Similar differences were observed after adjustment for the number of cigarettes smoked by the mother and by other smokers in the home in the previous 24 hours. The correlation coefficient between the number of cigarettes smoked by the mother and the breast milk cotinine concentration was significant (r = .69, P = 2 X 10(-4)). Moreover, urine cotinine values from the breast-fed babies increased with higher concentrations of cotinine in the mother's milk (r = .56, P = .02). These results provide evidence that breast-feeding increases exposure to tobacco smoke components in infants whose mothers smoke. This is yet another argument for strongly encouraging women who smoke to stop smoking during pregnancy and lactation.