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1.
J Headache Pain ; 24(1): 152, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940860

RESUMEN

BACKGROUND: Randomized clinical trials have demonstrated efficacy and safety of erenumab. The aim of this study is to evaluate the effectiveness and safety of erenumab in a real-world setting in French patients with migraine associated with extreme unmet needs. METHODS: This is a one year-prospective real-word study with enrolment of all consecutive adult patients included in the FHU InovPain registry who participated in a compassionate erenumab use program. RESULTS: Of 144 patients included, 140 patients (82.1% female / mean age of 50.9 ± 11.4) received at least one dose of erenumab and were concerned by effectiveness and safety assessment. All patients had failed 11 oral preventive treatments. Most of them suffered from chronic migraine (88.6%) and presented a medication overuse (90.7%) at baseline. Thirty-eight (27.1%) discontinued treatment during the 12-month follow-up, with 22 (15.7%), 11 (7.9%) and 5 (3.6%) patients before 3, 6 or 9 months of treatment. The proportion of ≥ 50% responders at M3, M6, M9 and M12 was 74/140 (52.9%), 69/118 (58.5%), 61/107 (57.0%) and 60/102 (58.8%) respectively. At M3, the rate of reversion from chronic migraine to episodic migraine was 57.3% and the rate of transition from medication overuse to non-overuse was 46.5%. For monthly migraine days, the median (IQR) was 18.0 (13.0-26.0), 9.0 (5.0-17.0), 7.5 (5.0-14.0), 8.0 (5.0-12.5) and 8.0 (5.0-12.0) at M0, M3, M6, M9 and M12 respectively. For HIT-6 score, the median (IQR) was 68.0 (63.8-73.3), 60.0 (54.0-65.0), 60.0 (50.3-53.0), 59.0 (50.0-63.0) and 58.0 (50.0-62.9) at M0, M3, M6, M9 and M12 respectively. Fifty-three (37.9%) patients reported at least one of the following adverse events: cutaneous erythema and/or pain at the injection site for 42 (30%) patients, constipation for 22 (15.7%) patients, muscle spasm for 2 (1.4%) patients, alopecia for one (0.7%) patient and blood pressure increase in one (0.7%) patient. There was no serious adverse event. One female patient became pregnant after 5 months of exposure to erenumab with a safe evolution after treatment discontinuation. CONCLUSION: This first French real-world study related to migraine prevention with CGRP-mAbs confirms effectiveness and safety of erenumab in patients with extreme unmet needs.


Asunto(s)
Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina , Trastornos Migrañosos , Adulto , Humanos , Femenino , Persona de Mediana Edad , Masculino , Estudios Prospectivos , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/uso terapéutico , Método Doble Ciego , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/prevención & control , Resultado del Tratamiento
2.
World J Surg ; 41(12): 3120-3127, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28721572

RESUMEN

BACKGROUND: Intestinal injury is a rare injury in multiply traumatized patients, and its diagnosis remains difficult. Delayed diagnosis of an intestinal injury increases the risk of sepsis, multiple organ failure and mortality. The intestinal fatty acid-binding protein (I-FABP) is solely expressed in the intestine and is released extracellulary after tissue damage. This study evaluates the validity of I-FABP as an early biomarker to detect an abdominal injury and particularly an injury to the intestine. PATIENTS AND METHODS: Patients with an Abbreviated Injury Scale (AIS) score for abdominal body region (AIS abdomen) ≥3 were included in this study from 07/2006 to 12/2014. Of those, ten patients retrospectively had an intestinal injury (int. injury). According to the Injury Severity Score and the AIS abdomen, corresponding patients with an abdominal injury but without an intestinal injury (no int. injury) were included for matched-pair analysis. Twenty healthy volunteers served as controls. Plasma I-FABP levels were measured at admission to the emergency room and up to 10 days daily (d1-d10). RESULTS: Median I-FABP levels were significantly higher in the "int. injury" group compared to the "no int. injury" group [2101.0 pg/ml (IQR = 1248.1-4117.8) vs. 351.4 pg/ml (IQR = 287.6-963.3), p < 0.05]. Furthermore, I-FABP levels of both groups were significantly higher compared to the control group [Ctrl: 127.2 pg/ml (IQR = 57.4-310.6), p < 0.05]. The time course of I-FABP levels showed a peak on the day of admission and a decline to the control levels in the further post-traumatic course. The development of complications such as single- or multi-organ failure, sepsis, acute respiratory distress syndrome, pneumonia and mortality was higher in the "int. injury" group; however, this difference was not statistically significant. CONCLUSION: This study confirmed our previous observation that I-FABP might be used as a suitable early biomarker for the detection of abdominal injuries in general. In addition and more specific, I-FABP may be a useful and promising parameter in the diagnosis of intestinal injuries.


Asunto(s)
Traumatismos Abdominales/sangre , Traumatismos Abdominales/diagnóstico , Proteínas de Unión a Ácidos Grasos/sangre , Intestinos/lesiones , Escala Resumida de Traumatismos , Traumatismos Abdominales/complicaciones , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo
3.
Skin Res Technol ; 19(1): e1-12, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22272747

RESUMEN

BACKGROUND: The confocal laser scanning microscope allows performing acquisition of several histological sections with precise visual morphological landmarks and their reconstruction. A powerful and modern confocal microscope enables to quickly reconstruct virtual 3D models. OBJECTIVE: The main goal was to develop a new platform to reconstruct complex mosaic serial data, interact with it in an immersive 3D environment, and give to the observers a feeling of 'presence' inside the skin. METHOD: We have developed novel methods that transform the data into alternative representation, well-suited to explore cutaneous structures in detail and to observe fields of data from different points of view. This new way of data reconstruction in volume requires optimization of intensities, automatic matching algorithms and depth alignment. RESULTS AND CONCLUSION: The new platform - SkinExplorer evolves as a 3D exploration prototype. This technology provides an immersive virtual environment to explore cutaneous microstructures. Several serial histological sections can be matched by stacks, aligned in depth by sections and merged together to be visualized as a whole. All these time-consuming steps have been dramatically speed-up using rapid image processing. The advantages of using virtual reality technologies such as the ones used in the SkinExplorer platform are automatic matching, precise alignment, better data perception, lower memory requirement, and higher quantity of simultaneously displayed data. This platform can render volumetric data and isosurfaces, separately or both at the same time. Lighting and depth perception are enhanced using 'Sphere Mapping', 'Ambient Occlusion', and 'Halo' methods when displaying iso-surfacic volume models with high complexity depth. The assets of the platform are to interpret complex three-dimensional data, to observe and explore 3D virtual models, and to show effects of cosmetic treatments.


Asunto(s)
Simulación por Computador , Dermoscopía/métodos , Imagenología Tridimensional/métodos , Microscopía Confocal/métodos , Piel/citología , Piel/patología , Algoritmos , Dermoscopía/instrumentación , Elasticidad , Diseño de Equipo , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/instrumentación , Masculino , Microscopía Confocal/instrumentación , Modelos Teóricos , Programas Informáticos , Interfaz Usuario-Computador
4.
J Exp Med ; 175(2): 377-85, 1992 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-1370681

RESUMEN

Type I allergy is a major health problem in industrialized countries where up to 15% of the population suffer from allergic symptoms (rhinitis, conjunctivitis, and asthma). Previously, we identified a cDNA clone that encoded a birch pollen allergen as profilin. Profilins constitute a ubiquitous family of proteins that control actin polymerization in eukaryotic cells; in particular, profilin participates in the acrosomal reaction of animal sperm cells. Although profilins had been unknown in plants so far, our finding led to the assumption that profilins might have similar functions in pollens during plant fertilization and therefore represent allergenic components in almost all pollens. We show that profilins are prominent allergens that can be isolated from tree pollens (Betula verrucosa, birch), from pollens of grasses (Phleum pratense, timothy grass), and weeds (Artemisia vulgaris, mugwort). About 20% of all pollen allergic patients tested (n = 65) displayed immunoglobulin E (IgE) reactivity to recombinant birch profilin that was expressed in pKK223-3. An IgE inhibition experiment performed with recombinant birch profilin and purified natural profilins from timothy grass and mugwort indicates common IgE epitopes. Moreover, all pollen profilins purified from these far distantly related plant species, and likewise the purified recombinant birch profilin, are able to elicit dose-dependent histamine release via high affinity Fc epsilon receptor of blood basophils from profilin allergic patients. The presence of profilin and possibly related proteins as crossreacting allergenic components in various plants therefore provides an explanation as to why certain allergic patients display type I allergic reactions with pollens and even food from distantly related plants. A functional pan-allergen, like profilin, available as purified recombinant protein, may be a useful diagnostic and probably therapeutic reagent.


Asunto(s)
Alérgenos/inmunología , Proteínas Contráctiles , Proteínas de Microfilamentos/inmunología , Polen/inmunología , Alérgenos/genética , Alérgenos/aislamiento & purificación , Animales , Cromatografía de Afinidad , Reacciones Cruzadas/inmunología , Electroforesis en Gel de Poliacrilamida , Epítopos/inmunología , Expresión Génica , Liberación de Histamina/inmunología , Humanos , Hipersensibilidad/inmunología , Immunoblotting , Inmunoglobulina E/inmunología , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/aislamiento & purificación , Profilinas , Conejos , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Transfección
5.
J Exp Med ; 186(9): 1557-65, 1997 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-9348313

RESUMEN

A panel of monoclonal antibodies was raised from mice immunized with a membrane preparation from Entamoeba histolytica, the pathogenic species causing invasive amebiasis in humans. Antibody EH5 gave a polydisperse band in immunoblots from membrane preparations from different E. histolytica strains, and a much weaker signal from two strains of the nonpathogenic species Entamoeba dispar. Although the exact chemical structure of the EH5 antigen is not yet known, the ability of the antigen to be metabolically radiolabeled with [32P]phosphate or [3H]glucose, its sensitivity to digestion by mild acid and phosphatidylinositol-specific phospholipase C, and its specific extraction from E. histolytica trophozoites by a method used to prepare lipophosphoglycans from Leishmania showed that it could be classified as an amebal lipophosphoglycan. Confocal immunofluorescence and immunogold labeling of trophozoites localized the antigen on the outer face of the plasma membrane and on the inner face of internal vesicle membranes. Antibody EH5 strongly agglutinated amebas in a similar way to concanavalin A (Con A), and Con A bound to immunoaffinity-purified EH5 antigen. Therefore, surface lipophosphoglycans may play an important role in the preferential agglutination of pathogenic amebas by Con A. The protective ability of antibody EH5 was tested in a passive immunization experiment in a severe combined immunodeficient (SCID) mouse model. Intrahepatic challenge of animals after administration of an isotype-matched control antibody or without treatment led to the development of a liver abscess in all cases, whereas 11 out of 12 animals immunized with the EH5 antibody developed no liver abscess. Our results demonstrate the importance and, for the first time, the protective capacity of glycan antigens on the surface of the amebas.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Antiprotozoarios/uso terapéutico , Antígenos de Protozoos/inmunología , Entamoeba histolytica/inmunología , Entamebiasis/prevención & control , Glicoesfingolípidos/inmunología , Proteínas de la Membrana/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/metabolismo , Anticuerpos Antiprotozoarios/biosíntesis , Anticuerpos Antiprotozoarios/metabolismo , Antígenos de Protozoos/química , Antígenos de Protozoos/ultraestructura , Sitios de Unión de Anticuerpos , Concanavalina A/metabolismo , Entamoeba histolytica/ultraestructura , Entamebiasis/inmunología , Entamebiasis/parasitología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Glicoesfingolípidos/química , Inmunización Pasiva , Immunoblotting , Proteínas de la Membrana/química , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Microscopía Confocal , Microscopía Electrónica , Unión Proteica/inmunología , Proteínas Protozoarias/inmunología
6.
J Fr Ophtalmol ; 43(3): 205-210, 2020 Mar.
Artículo en Francés | MEDLINE | ID: mdl-31982180

RESUMEN

INTRODUCTION: Uveitis-Glaucoma-Hyphema syndrome (UGH) is caused by mechanical chafing of anterior segment structures by an intraocular lens, especially an anterior chamber lens. The objective of this study was to characterise the clinical course and risk factors of UGH syndrome at a time when posterior chamber implantation is the gold standard. PATIENTS AND METHODS: This was a retrospective study of 30 cases of UGH syndrome managed between January 2014 and September 2018. Data from the initial clinical examination, the type of implant involved and the clinical management were analysed. RESULTS: Thirty eyes of 28 patients were included. Intra ocular lenses were iris-sutured (15/30, 50 %), in the bag (6/30, 20 %), scleral-fixated (4/30, 13.3 %), in the ciliary sulcus (3/30,10 %) or "in and out" (2/30, 6.7 %). Initial management was medical (18 eyes) or surgical (12 eyes). Surgical procedures were explantation (n=4), IOL repositioning (n=7) or trabeculectomy (n=1). Recurrences occurred with medical treatment (9/18), but not in the surgical group (p=0.02). Ocular hypertension became chronic in 19 cases out of 30 (63.3 %). CONCLUSION: UGH syndrome can be caused by any type of pseudophakic lens. An intraocular lens in the bag should not rule out the diagnosis. Despite the decreasing popularity of anterior chamber intraocular lens implantation, UGH syndrome remains a current condition and must be recognised in order to adapt therapeutic management.


Asunto(s)
Glaucoma , Hipema , Uveítis , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Francia/epidemiología , Glaucoma/epidemiología , Glaucoma/etiología , Glaucoma/patología , Glaucoma/terapia , Humanos , Hipema/epidemiología , Hipema/etiología , Hipema/patología , Hipema/terapia , Implantación de Lentes Intraoculares/efectos adversos , Lentes Intraoculares/efectos adversos , Lentes Intraoculares/clasificación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Síndrome , Uveítis/epidemiología , Uveítis/etiología , Uveítis/patología , Uveítis/terapia
7.
Science ; 253(5019): 557-60, 1991 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-1857985

RESUMEN

A complementary DNA encoding a pollen allergen from white birch (Betula verrucosa) that was isolated from a pollen complementary DNA library with serum immunoglobulin E from a birch pollen-allergic individual revealed significant sequence homology to profilins. The recombinant protein showed high affinity to poly-L-proline. Immunoglobulin E antibodies from allergic individuals bound to natural and recombinant birch profilin and also to human profilin. In addition, birch and human profilin induced histamine release from blood basophils of profilin-allergic individuals, but not of individuals sensitized to other plant allergens. The structural similarity of conserved proteins might therefore be responsible for maintaining immunoglobulin E antibody titers in type I allergy.


Asunto(s)
Hipersensibilidad , Inmunoglobulina E/inmunología , Proteínas de Microfilamentos/inmunología , Polen/inmunología , Secuencia de Aminoácidos , Proteínas Contráctiles/inmunología , Biblioteca de Genes , Humanos , Immunoblotting , Proteínas de Microfilamentos/genética , Datos de Secuencia Molecular , Profilinas , Proteínas Recombinantes/inmunología , Saccharomyces cerevisiae/genética , Homología de Secuencia de Ácido Nucleico
8.
Biologicals ; 37(6): 407-9; discussion 421-3, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19717309

RESUMEN

Numerous variations to a manufacturing process may take place during the life cycle of a vaccine. To support these variations, the regulator requires providing stability data according to the existing ICH guidelines; these have been designed for documenting the licence of a new vaccine. Comparative studies and adapted stability designs specific to the variation will give far more confidence to the manufacturer and the regulator than the classical model. The following case study applied to a change of a stopper illustrates this approach.


Asunto(s)
Química Farmacéutica/métodos , Embalaje de Medicamentos/métodos , Estabilidad de Medicamentos , Licencia en Farmacia , Vacunas/farmacocinética , Química Farmacéutica/legislación & jurisprudencia , Embalaje de Medicamentos/legislación & jurisprudencia , Almacenaje de Medicamentos , Humanos , Proyectos de Investigación , Vacunas/normas , Vacunas/provisión & distribución
9.
Biologicals ; 37(6): 403-6; discussion 421-3, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19853472

RESUMEN

Stability studies represent a significant workload for both manufacturers and regulatory reviewers and therefore a careful selection of the study design and of the stability indicator test is required to make sure that the study will provide the relevant information. Moreover, alternatives to the existing regulatory approaches should be favoured in order to better or quicker analyze the impact of a specific change. In this article, examples of alternative approaches are given. For the stability monitoring study, emphasis is put on the bulk stability program. Concerning comparability stability study, two case studies illustrating how accelerated stability studies could be used to support manufacturing changes are presented.


Asunto(s)
Química Farmacéutica/legislación & jurisprudencia , Evaluación de Medicamentos/métodos , Estabilidad de Medicamentos , Licencia en Farmacia , Vacunas/farmacocinética , Química Farmacéutica/métodos , Evaluación de Medicamentos/legislación & jurisprudencia , Liofilización/métodos , Liofilización/normas , Humanos , Vacunas/normas , Estudios de Validación como Asunto
10.
Adv Parasitol ; 65: 51-190, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18063096

RESUMEN

The intestinal parasite Entamoeba histolytica is one of the first protists for which a draft genome sequence has been published. Although the genome is still incomplete, it is unlikely that many genes are missing from the list of those already identified. In this chapter we summarise the features of the genome as they are currently understood and provide previously unpublished analyses of many of the genes.


Asunto(s)
Entamoeba histolytica/genética , Genes Protozoarios , Genoma de Protozoos/genética , Animales , Entamoeba histolytica/aislamiento & purificación , Entamoeba histolytica/fisiología , Regulación de la Expresión Génica
11.
Pharmeuropa Bio ; 2006(1): 7-14, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17270127

RESUMEN

The discontinuation of the Auszyme kit used by vaccine manufacturers and national control laboratories to determine the Hepatitis B surface antigen (HBsAg) content of hepatitis B vaccines has led GlaxoSmithKline (GSK) to develop an alternative inhibition ELISA method. Validation of this ELISA was performed according to The International Conference of Harmonization and reproducibility was assessed in a feasibility study with four Official Medicines Control Laboratories (OMCLs). The dose response curve demonstrated linearity (R2>0.99) in the range of 60-360 ng/ml HBsAg. The repeatability (CV<7%), intermediate precision (CV<10%) and accuracy (91-113% recovery) were similar to the Auszyme method. The commercial antibodies used in the assay were shown to contain antibodies that bind to a protective epitope of HBsAg and the specificity of the method for HBsAg was demonstrated. There was a good concordance with the Auszyme method, although the ELISA yielded higher results (25.3 vs. 24.4 micro.g/ml for Engerix-B (n=64), 28.9 vs. 27.0 micro.g/ml for Twinrix (n= 69) and 25.5 vs. 21.6 micro.g/ml for Infanrix penta (n=62)). The method was successfully transferred to the four OMCLs. It has been demonstrated that the ELISA is suitable for its intended purpose with hepatitis B-containing vaccines from GSK and thus could be used for these vaccines by national control laboratories and authorities. Further validation studies should focus on the use of this ELISA with vaccines from other manufacturers.


Asunto(s)
Anticuerpos contra la Hepatitis B/química , Antígenos de Superficie de la Hepatitis B/química , Vacunas contra Hepatitis B/química , Juego de Reactivos para Diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Estudios de Evaluación como Asunto , Anticuerpos contra la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Mol Immunol ; 33(4-5): 417-26, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8676893

RESUMEN

Grass pollen allergens are potent elicitors of Type I allergy. More than 95% of grass pollen allergic patients display IgE-cross-reactivity to group I grass pollen allergens of different grass species. A cDNA coding for the major timothy grass pollen allergen, Phl p I, was isolated previously. To investigate the presence of common IgE-epitopes among naturally occurring group I grass pollen isoallergens, Phl p I was expressed in Escherichia coli and used for IgE-absorption experiments. Recombinant Phl p I was able to inhibit IgE-binding to most of group I isoallergens from seven grass species as identified by two dimensional electrophoresis. When tested in competitive ELISA experiments, recombinant Phl p I bound a high percentage of grass pollen specific IgE. The results indicate that recombinant Phl p I shares many of the IgE-epitopes with natural group I grass pollen allergens and hence may represent a useful tool for specific diagnosis and therapy of grass pollen allergy.


Asunto(s)
Alérgenos/inmunología , Epítopos , Inmunoglobulina E/inmunología , Proteínas de Plantas/inmunología , Polen/inmunología , Electroforesis en Gel Bidimensional , Ensayo de Inmunoadsorción Enzimática , Humanos , Proteínas Recombinantes/inmunología
14.
Gene ; 74(2): 335-45, 1988 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-3149944

RESUMEN

A set of seven monoclonal antibodies (MAb) directed against outer membrane proteins of Pseudomonas aeruginosa has been examined by Western blot analysis, indirect immunofluorescence tests and subclass typing. The hybridoma cell line secreting MAb 6A4, which reacts with outer membrane protein I, belongs to the IgG2a subclass and crossreacts with the 17 P. aeruginosa serotypes as listed in the International Antigenic Typing System, was selected as source for the preparation of poly(A)+RNA which in turn was used as template for cDNA synthesis and cloning. Full length cDNA clones of the gamma heavy chain as well as the kappa light chain were obtained and characterized by nucleotide sequence analysis. The complete cDNA sequences coding for the heavy and light chains will be the prerequisite for the construction and heterologous expression of a chimeric human-mouse monoclonal antibody which might be used in therapy of P. aeruginosa infections.


Asunto(s)
Anticuerpos Monoclonales/genética , Proteínas de la Membrana Bacteriana Externa/inmunología , Clonación Molecular , ADN/genética , Pseudomonas aeruginosa/inmunología , Secuencia de Aminoácidos , Animales , Formación de Anticuerpos , Líquido Ascítico/análisis , Proteínas de la Membrana Bacteriana Externa/genética , Secuencia de Bases , Northern Blotting , ADN/biosíntesis , Hibridomas , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Plásmidos
15.
Mol Biochem Parasitol ; 90(1): 121-9, 1997 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-9497037

RESUMEN

Entamoeba histolytica and Entamoeba dispar have only recently been defined as two separate species. E. histolytica, the pathogenic species, is the microorganism causing invasive intestinal amoebiasis and/or liver abscess, while the morphologically similar E. dispar is nonpathogenic and noninvasive. The gold standard for the distinction of the two species has been the isoenzyme electrophoresis of phosphoglucomutases (EC 5.4.2.2) and hexokinases (EC 2.7.1.1), but there had also been a controversy about the possibility of a conversion of isoenzyme patterns. In this study, we cloned the phosphoglucomutase (PGM) cDNAs from the pathogenic and the nonpathogenic species. The deduced amino acid sequences were only 2.4% different. The cDNAs were expressed in Escherichia coli under the control of a T7 RNA polymerase promoter. The recombinant polypeptides displayed strong phosphoglucomutase activity, each of the recombinant enzymes comigrated with its natural counterpart from E. histolytica and E. dispar in the starch gel electrophoresis. Our results give a biochemical interpretation of the PGM isoenzyme pattern and support the clear distinction between the two species.


Asunto(s)
Entamoeba histolytica/enzimología , Entamoeba/enzimología , Fosfoglucomutasa/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Southern Blotting , Clonación Molecular , ADN Complementario , Electroforesis en Gel de Almidón , Entamoeba/clasificación , Entamoeba/genética , Entamoeba histolytica/clasificación , Entamoeba histolytica/genética , Genes Protozoarios , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Datos de Secuencia Molecular , Fosfoglucomutasa/genética , Fosfoglucomutasa/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Especificidad de la Especie
16.
Mol Biochem Parasitol ; 59(2): 315-22, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8341328

RESUMEN

Entamoeba histolytica has an unusual nuclear structure characterized by a low degree of chromatin condensation and the absence of stainable metaphase chromosomes. Although nucleosome-like particles were observed, no information about histones was available so far. In this paper we describe a cDNA clone with significant homology to H3 histones that was isolated from a library of pathogenic E. histolytica. The complete cDNA encodes a 15-kDa polypeptide, which like the histone sequence from Volvox carteri is shorter by one residue than the human homologue. The amino acid sequence has only 69% identity with human H3.3 histone and 67% identity with the human H3.1 histone. This is the highest degree of sequence divergence observed for any eukaryote H3 histone sequence. Our results indicate that this divergence may contribute to the unusual chromatin structure of E. histolytica.


Asunto(s)
ADN Protozoario/genética , Entamoeba histolytica/genética , Histonas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromatina/fisiología , Clonación Molecular , ADN Protozoario/aislamiento & purificación , Entamoeba histolytica/patogenicidad , Biblioteca de Genes , Variación Genética , Humanos , Datos de Secuencia Molecular , Peso Molecular , Reacción en Cadena de la Polimerasa/métodos , Homología de Secuencia de Aminoácido
17.
Mol Biochem Parasitol ; 54(2): 175-83, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1435858

RESUMEN

In order to investigate the humoral immune response against Entamoeba histolytica a lambda ZapII cDNA library was constructed from trophozoites of the pathogenic E. histolytica strain SFL-3. The library was screened with serum IgG from a patient with invasive amoebiasis. Forty-nine immunopositive lambda clones were isolated and partial sequences from the inserts were obtained. By comparison of the sequences with the merged database MIPSX from the Martinsried Institute for Protein Sequences we were able to identify homologous proteins for 36 of the clones. Twenty-six of the clones encoded intracellular proteins, among these, the major part (16 clones) were highly homologous to the eukaryotic 70-kDa heat shock proteins (Hsps). The open reading frame of one complete clone encodes a protein of 656 amino acid residues of 71.5 kDa which has 69.8% sequence identity with the human Hsp70 protein. In a larger screening experiment only 3 out of 12 patients detected with their IgG the phage which expressed the 70-kDa heat shock protein(s).


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Entamoeba histolytica/inmunología , Entamebiasis/inmunología , Proteínas de Choque Térmico/inmunología , Inmunoglobulina G/sangre , Proteínas Protozoarias/inmunología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Southern Blotting , ADN Protozoario/genética , Entamoeba histolytica/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Proteínas Protozoarias/genética , Proteínas Protozoarias/aislamiento & purificación , ARN Protozoario/genética
18.
Mol Biochem Parasitol ; 86(1): 85-94, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9178270

RESUMEN

The electrophoretic patterns of hexokinase and phosphoglucomutase have been widely used to distinguish Entamoeba histolytica from Entamoeba dispar isolates. Although E. histolytica and E. dispar, previously called pathogenic and nonpathogenic Entamoeba histolytica, differ clearly in sequences of many homologous genes, a conversion between the two has been reported by several laboratories, in each case showing the conversion of hexokinase (ATP, D-hexose 6-phosphotransferase, EC 2.7.1.1) isoenzyme patterns. An apparent mobility shift of this enzyme may either be due to posttranslational modification or processing, or to the appearance of a new isoform encoded by a second gene. In this study we observed that the four observed bands in the isoenzyme patterns of pathogenic and nonpathogenic forms of Entamoeba were correlated with four different cDNAs, and that the four recombinant hexokinases produced in Escherichia coli comigrated with their natural counterparts. Polymerase chain reaction (PCR) experiments did not reveal hidden genes which might be responsible for conversion phenomena. These results strongly support the redefinition of pathogenic and nonpathogenic Entamoeba histolytica as two closely related species Entamoeba histolytica and Entamoeba dispar.


Asunto(s)
Entamoeba histolytica/clasificación , Entamoeba/clasificación , Genes Protozoarios , Hexoquinasa/genética , Isoenzimas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Cartilla de ADN , Entamoeba/enzimología , Entamoeba histolytica/enzimología , Entamoeba histolytica/patogenicidad , Hexoquinasa/biosíntesis , Hexoquinasa/aislamiento & purificación , Isoenzimas/biosíntesis , Isoenzimas/aislamiento & purificación , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Alineación de Secuencia , Homología de Secuencia de Aminoácido
19.
Mol Biochem Parasitol ; 105(1): 71-80, 2000 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-10613700

RESUMEN

Entamoeba histolytica is responsible for amoebic colitis and liver abscess in humans. Entamoeba dispar is a closely related, morphologically indistinguishable nonpathogenic species. The hexokinase (ATP:D-hexose 6-phosphotransferase, EC 2.7.1.1) isoenzyme patterns distinguish the pathogenic and nonpathogenic species. Both species possess two hexokinases with very similar molecular mass and different isoelectric points. In order to understand the role of the two different isoenzymes from E. histolytica, we purified the recombinant hexokinases HXK1 and HXK2 and examined substrate spectrum and kinetic properties. The two enzymes displayed similar temperature and pH optima, they were inhibited strongly by AMP and ADP, not by glucose 6-phosphate. Both enzymes phosphorylated glucose well and were unable to phosphorylate fructose or galactose. We also detected significant differences. HXK1 was more sensitive to inhibition by AMP and ADP. Mannose was phosphorylated well by HXK1, but at a much lower rate by HXK2. We attempted to expand the substrate spectrum of E. histolytica HXK1 by modifying its active site to become similar to the active site of the fructose phosphorylating yeast hexokinase PII. None of the nine mutants gained any fructokinase activity, but all of them retained at least some glucokinase and mannokinase activity. Mannokinase activity was decreased drastically by two single amino acid exchanges, both of which contributed significantly to this effect. The data indicate that a complex interaction of a number of amino acid residues is necessary for the ability to phosphorylate a given hexose.


Asunto(s)
Entamoeba histolytica/enzimología , Hexoquinasa/metabolismo , Animales , Electroforesis en Gel de Poliacrilamida , Entamoeba histolytica/genética , Hexoquinasa/antagonistas & inhibidores , Hexoquinasa/química , Hexoquinasa/genética , Cinética , Modelos Moleculares , Mutación , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato
20.
Mol Biochem Parasitol ; 73(1-2): 189-98, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8577326

RESUMEN

The zymodemes, electrophoretic patterns of hexokinase, phosphoglucomutase and glucose phosphate isomerase isoenzymes, have been widely used to determine the pathogenicity of Entamoeba histolytica isolates. Although pathogenic and nonpathogenic forms of E. histolytica differ clearly in sequences of many homologous genes, a conversion between pathogenic and nonpathogenic zymodemes has been reported by several laboratories. To approach the question what might be the basis for the observed conversion, we examined the molecular biology of the hexokinase (ATP:D-hexose 6-phosphotransferase, EC 2.7.1.1) isoenzymes in pathogenic E. histolytica. We isolated two different cDNAs pHXK1 and pHXK2 coding for polypeptides with significant sequence similarity to hexokinases and deduced molecular masses of 49.8 kDa and 49.4 kDa. The two hexokinase sequences differed by 11% on the amino acid and by 8% on the nucleotide level. Expression of the cDNAs in Escherichia coli as nonfusion proteins gave two polypeptides with hexokinase activity. The recombinant Hxk1 and Hxk2 polypeptides comigrated with the more basic and more acidic isoforms of pathogenic amoebae in starch gel electrophoresis, as well as in low and high resolution isoelectric focussing gels. This identified the observed hexokinase isoenzymes of pathogenic E. histolytica as the products of two genes, hxk1 and hxk2.


Asunto(s)
Entamoeba histolytica/enzimología , Entamoeba histolytica/genética , Hexoquinasa/genética , Isoenzimas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Complementario/genética , ADN Protozoario/genética , Entamoeba histolytica/patogenicidad , Escherichia coli/genética , Genes Protozoarios , Hexoquinasa/aislamiento & purificación , Isoenzimas/aislamiento & purificación , Datos de Secuencia Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Especificidad de la Especie
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