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1.
J Environ Manage ; 249: 109351, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31419673

RESUMEN

Maize Cob Waste (MCW) is available worldwide in high amounts, as maize is the most produced cereal in the world. MCW is generally left in the crop fields, but due to its low biodegradability it has a negligible impact in soil fertility. Moreover, MCW can be used as substrate to balance the C/N ratio during the Anaerobic co-Digestion (AcoD) with other biodegradable substrates, and is an excellent precursor for the production of Activated Carbons (ACs). In this context, a biorefinery is theoretically discussed in the present review, based on the idea that MCW, after proper pre-treatment is valorised as precursor of ACs and as co-substrate in AcoD for biomethane generation. This paper provides an overview on different scientific and technological aspects that can be involved in the development of the proposed biorefinery; the major topics considered in this work are the following ones: (i) the most suitable pre-treatments of MCW prior to AcoD; (ii) AcoD process with regard to the critical parameters resulting from MCW pre-treatments; (iii) production of ACs using MCW as precursor, with the aim to use these ACs in biogas conditioning (H2S removal) and upgrading (biomethane production), and (iv) an overview on biogas upgrading technologies.


Asunto(s)
Biocombustibles , Zea mays , Anaerobiosis , Reactores Biológicos , Carbón Orgánico , Metano
2.
J Paediatr Child Health ; 58(9): 1697, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34652036
3.
J Allergy Clin Immunol ; 133(4): 1134-41, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24679470

RESUMEN

BACKGROUND: Severe combined immunodeficiency (SCID) is a syndrome characterized by profound T-cell deficiency. BCG vaccine is contraindicated in patients with SCID. Because most countries encourage BCG vaccination at birth, a high percentage of patients with SCID are vaccinated before their immune defect is detected. OBJECTIVES: We sought to describe the complications and risks associated with BCG vaccination in patients with SCID. METHODS: An extensive standardized questionnaire evaluating complications, therapeutics, and outcomes regarding BCG vaccination in patients given a diagnosis of SCID was widely distributed. Summary statistics and association analysis was performed. RESULTS: Data on 349 BCG-vaccinated patients with SCID from 28 centers in 17 countries were analyzed. Fifty-one percent of the patients had BCG-associated complications, 34% disseminated and 17% localized (a 33,000- and 400-fold increase, respectively, over the general population). Patients receiving early vaccination (≤1 month) showed an increased prevalence of complications (P = .006) and death caused by BCG-associated complications (P < .0001). The odds of experiencing complications among patients with T-cell numbers of 250/µL or less at diagnosis was 2.1 times higher (95% CI, 1.4-3.4 times higher; P = .001) than among those with T-cell numbers of greater than 250/µL. BCG-associated complications were reported in 2 of 78 patients who received antimycobacterial therapy while asymptomatic, and no deaths caused by BCG-associated complications occurred in this group. In contrast, 46 BCG-associated deaths were reported among 160 patients treated with antimycobacterial therapy for a symptomatic BCG infection (P < .0001). CONCLUSIONS: BCG vaccine has a very high rate of complications in patients with SCID, which increase morbidity and mortality rates. Until safer and more efficient antituberculosis vaccines become available, delay in BCG vaccination should be considered to protect highly vulnerable populations from preventable complications.


Asunto(s)
Vacuna BCG/efectos adversos , Inmunodeficiencia Combinada Grave/epidemiología , Vacuna BCG/inmunología , Preescolar , Comorbilidad , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Lactante , Recién Nacido , Estimación de Kaplan-Meier , Masculino , Prevalencia , Estudios Retrospectivos , Riesgo , Inmunodeficiencia Combinada Grave/diagnóstico , Inmunodeficiencia Combinada Grave/terapia , Vacunación/efectos adversos , Vacunación/legislación & jurisprudencia
4.
J Multidiscip Healthc ; 15: 999-1010, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35548670

RESUMEN

Background: Systemic autoinflammatory diseases (SAID) are characterized by inappropriate activation of the innate immune system and include not only monogenic periodic fever syndromes but also multifactorial conditions. As SAID are rare and represent a diagnostic challenge, a multidisciplinary approach is important to ensure successful diagnosis and adequate follow-up of these patients. Objective: To describe the organization of our multidisciplinary SAID clinic and to characterize our clinical experience, highlighting the benefits of multidisciplinary team management. Methods: Our SAID clinic takes place monthly and is managed by pediatric rheumatologists closely collaborating with pediatricians specialized in infectious diseases and immunodeficiencies and one medical geneticist. Patients' data are systematically incorporated in the Rheumatic Diseases Portuguese Register (Reuma.pt). Biological samples are stored in a biobank. We describe our clinical experience based on SAID patients registered into Reuma.pt/SAID between July 2011 and June 2020. Results: We have registered 176 patients, with a median age of disease onset of 3.1 ± 4.4 years and median age at disease diagnosis of 4.7 ± 4.0 years. Most patients were diagnosed with periodic fever, aphthous stomatitis, pharyngitis, adenitis syndrome (PFAPA) (n=133), 20 with undefined SAID (uSAID) and 13 with monogenic SAID, including familial Mediterranean fever (FMF) (n=5), tumor necrosis factor receptor-associated periodic syndrome (TRAPS) (n=1), cryopyrin-associated periodic disease (CAPS) (n=1), and hyperimmunoglobulin D syndrome/mevalonate kinase deficiency (HIDS/MKD) (n=2). A genetic test was performed in 31 patients (18%), and in 26% of these a mutation responsible for the phenotype was found. Thirty-four patients (19%) achieved remission. Conclusion: FMF was the most common monogenic SAID and the percentage of patients with an identified causal mutation was low. A structured electronic clinical record coupled with a biobank and a multidisciplinary approach are crucial to ensure successful diagnosis and adequate follow-up of these patients.

5.
Membranes (Basel) ; 12(1)2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-35054541

RESUMEN

Carbon dioxide (CO2) capture has become of great importance for industrial processes due to the adverse environmental effects of gas emissions. Mixed matrix membranes (MMMs) have been studied as an alternative to traditional technologies, especially due to their potential to overcome the practical limitations of conventional polymeric and inorganic membranes. In this work, the effect of using different ionic liquids (ILs) with the stable metal-organic framework (MOF) ZIF-8 was evaluated. Several IL@ZIF-8 composites and IL@ZIF-8 MMMs were prepared to improve the selective CO2 sorption and permeation over other gases such as methane (CH4) and nitrogen (N2). Different ILs and two distinct loadings were prepared to study not only the effect of IL concentration, but also the impact of the IL structure and affinity towards a specific gas mixture separation. Single gas sorption studies showed an improvement in CO2/CH4 and CO2/N2 selectivities, compared with the ones for the pristine ZIF-8, increasing with IL loading. In addition, the prepared IL@ZIF-8 MMMs showed improved CO2 selective behavior and mechanical strength with respect to ZIF-8 MMMs, with a strong dependence on the intrinsic IL CO2 selectivity. Therefore, the selection of high affinity ILs can lead to the improvement of CO2 selective separation for IL@ZIF-8 MMMs.

6.
J Nanosci Nanotechnol ; 10(4): 2537-46, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20355459

RESUMEN

We have carried out configurational-bias Grand Canonical Monte Carlo simulations of propane and propylene adsorption onto homogeneous bundles of single-walled carbon nanotubes, at ambient temperature (T = 298.15 K) and over a pressure range of 0.1 bar < or = p < 10.4 bar. The distinct contributions from external sites (grooves and external surface) and endohedral volume (inter- and intra-tubular) are individually addressed for bundles with nanotube diameters (D) within the range 11.0 A < D < or = 18.1 A. The different contributions from the various adsorption sites are interpreted from a molecular perspective, which takes into account both the skeletal geometry of the bundle and individual tube diameter. The resulting microscopic picture is then related to a macroscopic measurable isotherm by modeling the nanotube bundles, as a function of a characteristic hydraulic diameter (Dh) over the range 100 A < or = Dh < or = 310 A. A previously unobserved anisotropic behavior of the adsorption isotherm for the peripheral surface of the bundles as a function of hydraulic diameter is reported.

7.
Waste Manag ; 105: 170-179, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32070820

RESUMEN

Porous carbons from digestate-derived hydrochar were produced, characterized and their performance to reclaim phosphate from water was evaluated as a preliminary approach to demonstrate their practical application. In a first step, the digestate was converted into hydrochars through hydrothermal carbonization by using two different pH conditions: 8.3 (native conditions) and 3.0 (addition of H2SO4). The resulting hydrochars did not present significant differences. Consecutively, the hydrochars were activated with KOH to produce activated carbons with enhanced textural properties. The resulting porous carbons presented marked differences: the AC native presented a lower ash content (20.3 wt%) and a higher surface area (SBET = 1106 m2/g) when compared with the AC-H2SO4 (ash content = 43.7 wt% SBET = 503 m2/g). Phosphorus, as phosphate, is a resource present in significative amount in wastewater, causing serious problems of eutrophication. Therefore, the performance of the porous carbons samples to recover phosphate - P(PO43-) - from water was evaluated through exploitation assays that included kinetic studies. The lumped model presented a good fitting to the kinetic data and the obtained uptake capacities were the same for both carbons, 12 mg P(PO43-)/g carbon. Despite the poorer textural properties of AC-H2SO4, this carbon was richer in Ca, Al, Fe, K, and Mg cations which promoted the formation of mineral complexes with phosphate anions. The results obtained in this work are promising for the future development of P(PO43-) enriched carbons that can be used thereafter as biofertilizers in soil amendment applications.


Asunto(s)
Biocombustibles , Carbón Orgánico , Cinética , Porosidad , Suelo
8.
Front Chem ; 8: 590191, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33304882

RESUMEN

Global warming is arguably the biggest scientific challenge of the twenty-first century and its environmental consequences are already noticeable. To mitigate the emissions of greenhouse gases, particularly of CO2, there is an urgent need to design materials with improved adsorbent properties. Five different magnetic ionic liquids were impregnated into the metal-organic framework ZIF-8. The composites were produced by a direct-contact method, and their performance as sorbents for gas separation applications was studied. The impact of the ionic liquid anion on the sorption capacity and ideal CO2/CH4 and CO2/N2 selectivities were studied, focusing on understanding the influence of metal atom and ligand on the adsorbent properties. Reproducible methodology, along with rigorous characterization, were established to assess the impact of the ionic liquid on the performance of the composite materials. Results show that the ionic liquid was well-impregnated, and the ZIF-8 structure was maintained after ionic liquid impregnation. The produced composites were of microporous nature and were thermally stable. CO2, CH4, and N2 adsorption-desorption isotherms were obtained at 303 K and between 0 and 16 bar. The adsorption-desorption data of the composites were compared with that obtained for original ZIF-8. The general trend in composites is that the increased gas uptake per available pore volume compensates the pore volume loss. Adsorption data per unit mass showed that composites have reversible sorption, but inferior gas uptake at all pressure ranges. This is due to the observed total pore volume loss by the ionic liquid pore occupation/blockage. In most cases, composites showed superior selectivity performance at all pressure range. In particular, the composite [C4MIM]2[MnCl4]@ZIF-8 shows a different low-pressure selectivity trend from the original MOF, with a 33% increase in the CO2/N2 selectivity at 1 bar and 19% increase in the CO2/CH4 selectivity at 10 bar. This material shows potential for use in a post-combustion CO2 capture application that can contribute to greenhouse gas mitigation.

9.
Waste Manag ; 94: 136-145, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31279389

RESUMEN

Two activated carbons (ACs) were prepared by physical activation of Maize Cob Waste (MCW) with CO2, during 2 and 3 h (MCW(PA)2h and MCW(PA)3h, respectively). Two other ACs were prepared by chemical activation: a) MCW(LD) - MCW was impregnated with anaerobic liquid digestate (LD) and carbonized under N2 atmosphere; and b) CAR-MCW(LD) - previously carbonized MCW was impregnated with LD and carbonized under N2 atmosphere. All ACs were fully characterized for textural and chemical properties, and then used in dynamic H2S removal assays from real biogas samples. Regarding H2S removal, the ACs that were physically activated behaved much better than the impregnated ones: MCW(PA)3h and MCW(PA)2h showed H2S uptake capacities of 15.5 and 0.65 mg g-1, respectively, while MCW(LD) and CAR-MCW(LD) showed values of 0.47 and 0.25 mg g-1, respectively. This may indicate that textural properties (surface area and microporosity) are more important than mineral content in H2S removal. Effectively, both surface area and micropore volume were much higher for the samples of MCW(PA)3h (SBET = 820 m2 g-1 and Vmicro = 0.32 cm3 g-1) and MCW(PA)2h (SBET = 630 m2 g-1 and Vmicro = 0.21 cm3 g-1) than for the ACs that were chemically activated (SBET = 38.0 m2 g-1 and Vmicro = 0.01 cm3 g-1 for MCW(LD); SBET = 8.0 m2 g-1 and Vmicro = 0.01 cm3 g-1 for CAR-MCW(LD)). High oxygen content in MCW(PA)3h favoured the catalytic oxidation reaction of H2S, promoting its removal. The use of MCW as precursor and LD as activating agent of the ACs may contribute for the integrated management of maize wastes and to diversify the applications of anaerobic digestate.


Asunto(s)
Biocombustibles , Zea mays , Anaerobiosis , Carbón Orgánico
10.
Acta Med Port ; 32(7-8): 514-519, 2019 Aug 01.
Artículo en Portugués | MEDLINE | ID: mdl-31445531

RESUMEN

INTRODUCTION: Children with DiGeorge syndrome/chromosome 22q11.2 deletion syndrome might have a variable degree of immunodeficiency, which may limit the use of live vaccines. The aim of this study was to review the adverse effects of live vaccines and possible relation with immune status in patients with DiGeorge Syndrome/partial 22q11.2 deletion syndrome. MATERIAL AND METHODS: Retrospective study with analysis of the clinical records of children with chromosome 22q11.2 deletion syndrome and DiGeorge syndrome phenotype, followed in a Primary Immunodeficiency center. Data were collected on: demographic characteristics; medical and vaccination history with live vaccines; T-CD4+ lymphocyte counts and lymphocyte proliferative responses to antigens and mitogens; adverse reactions; vaccine failure. RESULTS: Twenty three children with DiGeorge syndrome/22q11.2 deletion syndrome were included, 65.2% male, with average age at diagnosis of 11.3 months. Eighteen children (78%) received bacillus Calmette-Guérin vaccine: all with evidence of thymic activity; three presented moderate T-CD4+ lymphopenia and abnormal lymphocyte proliferative responses; one had abnormal lymphocyte proliferative responses for mitogens, four for purified protein derivative and one for tetanus toxoid. Measles, mumps and rubella vaccine was administered to 15 children, three of them with moderate immunosuppression and abnormal lymphocyte proliferative responses. Live attenuated polio vaccine was administered to 4 children without immunosuppression and the rotavirus vaccine to three children, one with moderate immunosuppression. No significant adverse reactions were reported. DISCUSSION: These data are in line with the findings of other international studies. CONCLUSION: In our sample, live vaccines were well-tolerated, even in children with moderate T-CD4+ lymphopenia and abnormal lymphocyte proliferative responses to antigens/mitogens.


Introdução: A síndrome de DiGeorge/deleção 22q11.2 pode apresentar um grau variável de imunodeficiência, condicionando a utilização de vacinas vivas. Este estudo teve como objetivo documentar os efeitos adversos de vacinas vivas e possível relação com alterações imunitárias em crianças com síndrome de DiGeorge/deleção 22q11.2 parcial. Material e Métodos: Foi realizado um estudo retrospetivo por revisão dos processos clínicos das crianças com deleção do cromossoma 22q11.2 e fenótipo de síndrome de DiGeorge, seguidos num centro de referência de imunodeficiências primárias. Foi realizada colheita de dados, incluindo: características demográficas; história médica; historial de vacinação com vacinas vivas; contagem de linfócitos T-CD4+ e respostas proliferativas linfocitárias a antigénios e mitogénios; reações adversas; falências vacinais. Resultados: Foram incluídas 23 crianças com síndrome de DiGeorge/deleção 22q11.2, 65,2% do sexo masculino e idade média de diagnóstico de 11,3 meses. Destas, 18 crianças (78%) receberam a vacina bacillus Calmette-Guérin: todas com evidência de atividade tímica; três apresentaram linfopénia T-CD4+ moderada e respostas proliferativas linfocitárias anormais; uma com respostas proliferativas linfocitárias anormais para mitogénios, quatro para derivado de proteína purificada e uma para toxóide tetânico. A vacina tríplice contra o sarampo, parotidite e rubéola foi administrada a 15 crianças, três com imunossupressão moderada e respostas proliferativas linfocitárias anormais. A vacina viva atenuada contra poliomielite foi administrada a quatro crianças sem imunossupressão e a vacina contra o rotavírus a três crianças, uma com imunossupressão moderada. Não foram reportadas reações adversas. Discussão: Estes dados estão de acordo com as conclusões de outros estudos internacionais. Conclusão: Na nossa amostra, as vacinas vivas atenuadas foram bem toleradas, incluindo em crianças com linfopénia T-CD4+ moderada e com respostas proliferativas linfocitárias a antigénios/mitogénios anormais.


Asunto(s)
Síndrome de DiGeorge/inmunología , Tolerancia Inmunológica , Adyuvantes Inmunológicos/administración & dosificación , Vacuna BCG/administración & dosificación , Vacuna BCG/inmunología , Linfocitos T CD4-Positivos , Proliferación Celular , Niño , Preescolar , Femenino , Humanos , Huésped Inmunocomprometido , Lactante , Linfopenia/inmunología , Masculino , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Vacuna contra el Sarampión-Parotiditis-Rubéola/inmunología , Fenotipo , Vacuna Antipolio de Virus Inactivados/administración & dosificación , Estudios Retrospectivos , Vacunas contra Rotavirus/administración & dosificación , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/inmunología
11.
Dev Comp Immunol ; 32(10): 1231-41, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18514862

RESUMEN

In mammals, Toll-like receptors play a critical role in initiating innate immune responses and modulating adaptive immunity, by recognizing conserved microbial molecular patterns. This study was undertaken to identify specific features of the responses to synthetic toll-like receptor (TLR) agonists in goats, for the definition of tailored immunostimulation strategies. We show here, in contrast to what has been shown in mice, that mesenteric lymph nodes (MLNs) cells and splenocytes from neonatal goats produce much higher levels of TH1-type cytokines than adults in response to various TLR agonists. IL-12 was identified as a critical cytokine for IFNgamma production by CD8(+) neonatal cells. The higher level of IL-12 production by neonatal MLN and spleen cells than by adult cells was not correlated with a higher level of TLR expression or lower levels of production of the regulatory cytokine IL-10. In neonates, two cell populations-class II(+) CD8(+) and class II(+) CD8(-) cells-produce IL-12 in response to R848 and Poly I:C, respectively. Thus, goat kids have characteristics that could be exploited to favor development of the TH1-type responses critical for the control of intracellular pathogens.


Asunto(s)
Envejecimiento/inmunología , Citocinas/inmunología , Cabras/inmunología , Células TH1/inmunología , Receptores Toll-Like/inmunología , Animales , Animales Recién Nacidos , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Citocinas/biosíntesis , Citocinas/genética , Femenino , Ligandos , Masculino , Poli I-C/farmacología , Receptores Toll-Like/agonistas
12.
Waste Manag ; 72: 193-205, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29169860

RESUMEN

In the present work, the enhancement of biogas and methane yields through anaerobic co-digestion of the pre-hydrolised Organic Fraction of Municipal Solid Wastes (hOFMSW) and Maize Cob Wastes (MCW) in a lab-scale thermophilic anaerobic reactor was tested. In order to increase its biodegradability, MCW were submitted to an initial pre-treatment screening phase as follows: (i) microwave (MW) irradiation catalysed by NaOH, (ii) MW catalysed by glycerol in water and alkaline water solutions, (iii) MW catalysed by H2O2 with pH of 9.8 and (iv) chemical pre-treatment at room temperature catalysed by H2O2 with 4 h reaction time. The pre-treatments cataysed by H2O2 were performed with 2% MCW (wMCW/v alkaline water) at ratios of 0.125, 0.25, 0.5 and 1.0 (wH2O2/wMCW). The pre-treatment that presented the most favourable balance between sugars, lignin, cellulose and hemicellulose solubilisations, as well as low production of phenolic compound and furfural (inhibitors), was the chemical pre-treatment catalysed by H2O2, at room temperature, with a ratio of 0.5 wH2O2/wMCW (Pre1). This Pre1 was then optimised testing reaction times of 1, 2 and 3 days at a different pH (11.5) and MCW percentage (10% w/v). The optimised pre-treatment that presented the best results, considering the same criteria defined above, was the one carried out during 3 days, at pH 9.8 and 10% MCW w/v (Pre2). The anaerobic reactor was initially fed with the hOFMSW obtained from the hydrolysis tank of an industrial AD plant. The hOFMSW was than co-digested with MCW submitted to the pre-treatment Pre1. In another assay, hOFMSW was co-digested with MCW submitted pre-treatment Pre 2. The co-digestion of hOFMSW + Pre1 increased the biogas yield by 38.9% and methane yield by 29.7%, when compared to the results obtained with hOFMSW alone. The co-digestion of hOFMSW + Pre2 increased biogas yield by 46.0% and CH4 yield by 36.3%. In both cases, the methane content obtained in the biogas streams was above 66% v/v. These results show that pre-treatment with H2O2, at room temperature, is a promising low cost way to valorize MCW through co-digestion with hOFMSW.


Asunto(s)
Biocombustibles , Reactores Biológicos , Zea mays , Anaerobiosis , Peróxido de Hidrógeno , Metano , Eliminación de Residuos
13.
Vet J ; 174(1): 42-53, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16904353

RESUMEN

There is strong evidence to suggest that foot-and-mouth disease (FMD) can be transmitted by airborne virus up to many kilometres from a virus source. Atmospheric dispersion models are often used to predict where this disease might spread. This study investigated whether FMD virus (FMDV) aerosol has specific characteristics which need to be taken into consideration in these models. The characteristics and infectiousness of particles emitted by 12 pigs have been studied pre- and post-infection with O UKG 2001 FMDV. Aerosol generated by individual pigs was found log normally distributed in the range 0.015-20.0microm with concentrations between 1000 and 10000cm(-3) at the smallest size and <1cm(-3) above 10microm. No differences in either the total number of particles produced or their size distribution were detected between uninfected and infected pigs. However, a correlation between aerosol concentration and animal activity was found with a more active pig producing significantly greater concentrations than those that were less active. Viable virus was found up to a maximum of 6.3 log TCID(50)/24h/animal. The virus was distributed almost equally across the three size ranges; <3, 3-6 and >6microm. No correlation could be established between the production of virus and animal activity. In general the production of airborne virus closely followed the detection of viraemia in the blood and the presence of clinical symptoms. However, in one instance a pig excreted as much airborne virus as the other animals in the study, but with less virus detected in its blood. The results suggest that there is little merit in including a sophisticated virus release pattern based on physical activity periods or FMDV aerosol size spectrum, together with the appropriate dry deposition calculations, in models used to predict airborne spread of FMD. An estimate of the total daily virus production based on the clinical assessment of disease and virus strain is sufficient as input.


Asunto(s)
Microbiología del Aire , Brotes de Enfermedades , Virus de la Fiebre Aftosa/crecimiento & desarrollo , Fiebre Aftosa/transmisión , Enfermedades de los Porcinos/virología , Animales , Transmisión de Enfermedad Infecciosa/veterinaria , Femenino , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/química , Tamaño de la Partícula , Porcinos , Enfermedades de los Porcinos/transmisión
14.
Vet Microbiol ; 100(3-4): 233-40, 2004 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-15145501

RESUMEN

IFN-gamma is considered as a key factor in protection against heartwater of ruminants, caused by the obligate intracellular bacterium Ehrlichia ruminantium. In this study, a better definition of the molecular masses of IFN-gamma inducing proteins of the Gardel strain of E. ruminantium was obtained by the use of continuous flow electrophoresis (CFE) and sensitized polyclonal lymphocytes. Out of 15 E. ruminantium CFE fractions tested within the 14-39 kDa region, eight were commonly reacted to by all goats. Interestingly, half of these fractions fall within the 23-29 kDa region, shown previously to contain polymorphic B-cell epitopes. Thus, the results suggest that this region also contains T-cell epitopes potentially involved in protection. Also, several proteins were found to be more immunogenic than the serologically immunodominant MAP1 protein. Finally, high activity within the 15-19 kDa region was observed, which confirms previous work done with CD4+ T-cell lines obtained from cattle immunized with a South African strain of E. ruminantium. The proteins falling within the molecular weight ranges defined in this study may have potential as vaccine antigens.


Asunto(s)
Antígenos de Protozoos/aislamiento & purificación , Ehrlichia ruminantium/inmunología , Enfermedades de las Cabras/microbiología , Hidropericardio/inmunología , Interferón gamma/biosíntesis , Animales , Antígenos de Protozoos/inmunología , Concanavalina A/inmunología , Ehrlichia ruminantium/metabolismo , Electroforesis en Gel de Poliacrilamida/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de las Cabras/sangre , Cabras , Hidropericardio/sangre , Hidropericardio/prevención & control , Interferón gamma/inmunología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Peso Molecular , Vacunación/veterinaria
15.
Vet Immunol Immunopathol ; 98(1-2): 49-57, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15127841

RESUMEN

Interferon gamma (IFN-gamma) is considered as a key mediator of protective cell-mediated immunity against intracellular pathogens in general, and against Ehrlichia ruminantium, the causative agent of tick-borne heartwater disease of ruminants, in particular. However, the source of this important cytokine in animals immunized against E. ruminantium remains largely unknown. We have analyzed in goats protected by vaccination with a killed E. ruminantium vaccine, the potential of individual, genuine (i.e., non-cloned), T cell subsets to produce IFN-gamma after antigenic recall in vitro. In all vaccinated but none control animals, E. ruminantium-induced IFN-gamma secretion was observed in 24 h stimulated blood. Flow cytometric analysis of stimulated peripheral blood mononuclear cells (PBMCs) collected after each vaccine inoculation indicated that immune CD4+ and CD8+ T cells contribute to the same extent to the production of IFN-gamma, while WC1+ T cells are less important. This was confirmed by blocking the secretion of IFN-gamma with anti-classes I and II major histocompatibility complex antibodies. Blocking experiments also suggest that CD8+ need the help of CD4+ T cells in order to produce IFN-gamma. Thus, this work underlines the key role of CD4+ T cells in the production of IFN-gamma by immune goat PBMC. It also describes, for the first time in ruminants, E. ruminantium-specific CD8+ effector T cells. Since CD4+ and CD8+ T cells collectively contribute to the production of IFN-gamma in most vaccinated animals, and since these responses are associated with protection, it may be that a recombinant vaccine will need to incorporate E. ruminantium antigens capable of driving both responses.


Asunto(s)
Vacunas Bacterianas/farmacología , Ehrlichia ruminantium/inmunología , Enfermedades de las Cabras/inmunología , Enfermedades de las Cabras/prevención & control , Cabras/inmunología , Hidropericardio/inmunología , Hidropericardio/prevención & control , Interferón gamma/biosíntesis , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Antígenos de Histocompatibilidad Clase I , Antígenos de Histocompatibilidad Clase II , Isoanticuerpos/administración & dosificación , Cinética
16.
BMJ Case Rep ; 20142014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-25336558

RESUMEN

Langerhans cell histiocytosis (LCH) is a rare disease of unknown origin with a heterogeneous clinical presentation, varying from benign and self-limited to lethal. It is classified as single or multisystemic, according to the number of organs involved (one or at least two, respectively). Diagnosis can be challenging and is based on the histological and immunophenotypic examination of affected tissues. Secondary haemophagocytic lymphohistiocytosis is rarely reported in association with LCH and may impair its diagnosis. Some authors suggest that the coexistence of the two disorders is more than coincidental. We present a case of multisystem LCH in a 5-month-old infant, with all risk organs involved, in which severity and rapid progression reflect an association with haemophagocytic syndrome.


Asunto(s)
Histiocitosis de Células de Langerhans/complicaciones , Linfohistiocitosis Hemofagocítica/complicaciones , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Ácido Clavulánico/uso terapéutico , Clindamicina/uso terapéutico , Diagnóstico Diferencial , Transfusión de Eritrocitos/métodos , Resultado Fatal , Histiocitosis de Células de Langerhans/tratamiento farmacológico , Histiocitosis de Células de Langerhans/terapia , Humanos , Lactante , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Linfohistiocitosis Hemofagocítica/terapia , Masculino , Síndrome
17.
Int J Prosthodont ; 27(5): 472-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25191892

RESUMEN

The relationship of the convergence angle (CA) to the height of the axial walls is the most important factor for providing retention and resistance in tooth preparation for a complete crown. Several studies have shown that the ideal CA is difficult to achieve in clinical practice. The technique described in this article allows for the determination of the CA during the tooth preparation procedure, based on an instrument developed and created by the authors.


Asunto(s)
Coronas , Preparación Protodóncica del Diente/métodos , Retención de Prótesis Dentales , Diseño de Equipo , Humanos , Propiedades de Superficie , Diente/anatomía & histología , Preparación Protodóncica del Diente/instrumentación
18.
BMJ Case Rep ; 20132013 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-24027258

RESUMEN

A 14-year-old adolescent presented with a prolonged fever, abnormal liver function, anaemia, thrombocytopaenia, but a good general status. Diagnosis of hemophagocytic lymphohistiocytosis (HLH) was suspected, in spite of the initial indolent course. Secondary causes were excluded, but no specific mutation indicative of primary HLH was found. The patient started with specific therapy, but progressed with reactivations and later with persistently active disease. Haematopoietic stem cell transplantation was not successful and the adolescent died 7 months after diagnosis.


Asunto(s)
Linfohistiocitosis Hemofagocítica/diagnóstico , Adolescente , Antiinfecciosos/uso terapéutico , Resultado Fatal , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Inmunosupresores/uso terapéutico , Linfohistiocitosis Hemofagocítica/terapia
19.
PLoS One ; 6(1): e15921, 2011 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-21264246

RESUMEN

BACKGROUND: So far, human antibodies with good affinity and specificity for MUC1, a transmembrane protein overexpressed on breast cancers and ovarian carcinomas, and thus a promising target for therapy, were very difficult to generate. RESULTS: A human scFv antibody was isolated from an immune library derived from breast cancer patients immunised with MUC1. The anti-MUC1 scFv reacted with tumour cells in more than 80% of 228 tissue sections of mamma carcinoma samples, while showing very low reactivity with a large panel of non-tumour tissues. By mutagenesis and phage display, affinity of scFvs was increased up to 500fold to 5,7×10(-10) M. Half-life in serum was improved from below 1 day to more than 4 weeks and was correlated with the dimerisation tendency of the individual scFvs. The scFv bound to T47D and MCF-7 mammalian cancer cell lines were recloned into the scFv-Fc and IgG format resulting in decrease of affinity of one binder. The IgG variants with the highest affinity were tested in mouse xenograft models using MCF-7 and OVCAR tumour cells. However, the experiments showed no significant decrease in tumour growth or increase in the survival rates. To study the reasons for the failure of the xenograft experiments, ADCC was analysed in vitro using MCF-7 and OVCAR3 target cells, revealing a low ADCC, possibly due to internalisation, as detected for MCF-7 cells. CONCLUSIONS: Antibody phage display starting with immune libraries and followed by affinity maturation is a powerful strategy to generate high affinity human antibodies to difficult targets, in this case shown by the creation of a highly specific antibody with subnanomolar affinity to a very small epitope consisting of four amino acids. Despite these "best in class" binding parameters, the therapeutic success of this antibody was prevented by the target biology.


Asunto(s)
Anticuerpos Monoclonales , Neoplasias de la Mama/inmunología , Mucina-1/inmunología , Animales , Línea Celular Tumoral , Epítopos , Femenino , Humanos , Ratones , Biblioteca de Péptidos , Anticuerpos de Cadena Única , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Int J Pediatr ; 2010: 651023, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20628514

RESUMEN

A 14-year-old patient presented with bilateral pneumonia and pleural effusions, septic arthritis of the hip, deep venous thrombosis, and pulmonary thromboembolism. Methicillin-sensitive Staphylococcus aureus (S. aureus) containing the Panton Valentine Leukocidin (PVL) genes was isolated. Contraindication to anticoagulation prompted inferior vena cava filter placement. He completed 4 weeks of treatment with flucloxacillin, with good clinical outcome. S. aureus containing PVL genes should be sought in cases of necrotizing pneumonia as it seems to increase the risk of severe multifocal infection and thrombotic complications. There are few reports of placement of filters during S. aureus sepsis and bacteraemia. This case highlights that when anticoagulation is not feasible, an inferior vena cava filter can be inserted safely, even in patients with active sepsis and high risk for seeding of the filter. Long-term follow-up confirmed a successful outcome with sterilization of the septic thrombosis with no further pulmonary embolism or additional sepsis episodes.

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