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2.
Clin Exp Immunol ; 184(2): 183-96, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26724675

RESUMEN

Sjögren's syndrome (SS) is an autoimmune disease and the second most common chronic systemic rheumatic disorder. Prevalence of primary SS in the general population has been estimated to be approximately 1-3%, whereas secondary SS has been observed in 10-20% of patients with rheumatoid arthritis, systemic lupus erythematosus (SLE) and scleroderma. Despite this, its exact aetiology and pathogenesis are largely unexplored. Nuclear factor-kappa B (NF-κB) signalling mechanisms provide central controls in SS, but how these pathways intersect the pathological features of this disease is unclear. The ubiquitin-editing enzyme A20 (tumour necrosis factor-α-induced protein 3, TNFAIP3) serves as a critical inhibitor on NF-κB signalling. In humans, polymorphisms in the A20 gene or a deregulated expression of A20 are often associated with several inflammatory disorders, including SS. Because A20 controls the ectodysplasin-A1 (EDA-A1)/ectodysplasin receptor (EDAR) signalling negatively, and the deletion of A20 results in excessive EDA1-induced NF-κB signalling, this work investigates the expression levels of EDA-A1 and EDAR in SS human salivary glands epithelial cells (SGEC) and evaluates the hypothesis that SS SGEC-specific deregulation of A20 results in excessive EDA1-induced NF-κB signalling in SS. Our approach, which combines the use of siRNA-mediated gene silencing and quantitative pathway analysis, was used to elucidate the role of the A20 target gene in intracellular EDA-A1/EDAR/NF-κB pathway in SS SGEC, holding significant promise for compound selection in drug discovery.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Ectodisplasinas/metabolismo , Receptor Edar/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , FN-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Síndrome de Sjögren/patología , Proteínas de Unión al ADN/genética , Células Epiteliales/metabolismo , Humanos , Proteínas I-kappa B/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Inhibidor NF-kappaB alfa , Proteínas Nucleares/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , Glándulas Salivales/citología , Glándulas Salivales/metabolismo , Transducción de Señal , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa
3.
Rev Gastroenterol Mex ; 80(2): 135-43, 2015.
Artículo en Inglés, Español | MEDLINE | ID: mdl-26088570

RESUMEN

BACKGROUND: Type 1 diabetes (T1D) and celiac disease (CD) are the 2 most common autoimmune childhood diseases that share their HLA-DQ2 and DQ8 genetic origin. There has currently been an increase in both diseases worldwide. In children from the low-population State of Sonora (15 inhabitants/km(2)) in north-western Mexico, there is no information on their genetic risk or the distribution of the related alleles in the general population. AIMS: To compare the HLA-DQ allele frequency in a representative sample of newborns from Sonora with that of T1D and CD patients to determine the risk gradient, and to identify the presence of celiac autoimmunity in the T1D group. METHODS: The study included 397 Sonoran newborns, with 44 cases of T1D, and 25 CD cases. The CD and T1D cases were clinically diagnosed by specialists at the Hospital Infantil del Estado de Sonora, and the autoantibodies were determined by ELISA. Whole blood was collected, gDNA was extracted, and HLA-DQ2 and DQ8 were typed by PCR-SSP. The risk gradient was calculated by comparing the allele frequencies of the cases with those of the newborns. RESULTS: The Sonoran HLA-DQ risk heterodimer proportion was 16.1% for HLA-DQ2 and 13.6% for HLA-DQ8, with an HLA-DQ2:HLA-DQ8 ratio of 1.2:1. The DQ8/DQ2 genotype represented a 1:14 risk for T1D, whereas the DQ8/DQB1*0201 combination showed a 1:6 risk for CD. The prevalence of CD autoimmunity in T1D children was 7%. CONCLUSION: The Sonoran population has a distinctive HLA-DQ allele distribution due to its ancestry. The HLA-DQ8 combinations with DQ2 or one of its alleles conferred the highest risk for both diseases, and T1D and CD frequently appear together.


Asunto(s)
Enfermedad Celíaca/genética , Diabetes Mellitus Tipo 1/genética , Frecuencia de los Genes , Antígenos HLA-DQ/genética , Cadenas beta de HLA-DQ/genética , Adolescente , Enfermedad Celíaca/complicaciones , Enfermedad Celíaca/diagnóstico , Niño , Preescolar , Estudios Transversales , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/diagnóstico , Femenino , Marcadores Genéticos , Humanos , Recién Nacido , Masculino , México , Medición de Riesgo , Salud Rural
4.
BMC Nephrol ; 15: 159, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25273526

RESUMEN

BACKGROUND: This study aimed to measure the serum soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and interleukin-17A (IL-17A) levels in hypertensive patients with/without asymptomatic organ damage (AOD), as well as to determine the relationship between the serum sTWEAK and IL17-A levels, and carotid intima media thickness (CIMT), proteinuria, retinopathy, and the left ventricle mass index (LVMI). METHODS: The study included 159 patients diagnosed with and followed-up for primary hypertension (HT); 79 of the patients had AOD (61 female and 18 male) and 80 did not (52 female and 28 male). sTWEAK and IL-17A levels were measured in all patients. RESULTS: The sTWEAK level was significantly lower in the patients with AOD than in those without AOD (858.4 pg/mL vs. 1151.58 pg/mL, P = 0.001). The sTWEAK level was negatively correlated with the mean microalbuminuria level and LVMI. The median IL-17A level was significantly higher in the patients with AOD than in those without AOD (2.34 pg/mL vs. 1.80 pg/mL, P = 0.001). There was a positive correlation between mean IL-17A level, and mean microalbuminuria level, CIMT, and LVMI. Multivariate logistic regression analysis showed that patient age, sTWEAK level, and mean 24-h systolic blood pressure were predictors of AOD. CONCLUSIONS: The sTWEAK level was lower and IL-17A level was higher in the patients with AOD. It remains unknown if sTWEAK and IL-17A play a role in the pathophysiology of AOD. Prospective observational studies are needed to determine the precise role of sTWEAK and IL-17A in the development of target organ damage.


Asunto(s)
Hipertensión/sangre , Interleucina-17/sangre , Factores de Necrosis Tumoral/sangre , Adulto , Anciano , Albuminuria/sangre , Albuminuria/etiología , Antihipertensivos/uso terapéutico , Enfermedades Asintomáticas , Grosor Intima-Media Carotídeo , Citocina TWEAK , Diástole , Progresión de la Enfermedad , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Retinopatía Hipertensiva/sangre , Retinopatía Hipertensiva/etiología , Hipertrofia Ventricular Izquierda/sangre , Hipertrofia Ventricular Izquierda/etiología , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Curva ROC , Factores de Riesgo , Sístole
5.
Rev Gastroenterol Mex ; 78(4): 211-8, 2013.
Artículo en Español | MEDLINE | ID: mdl-24210306

RESUMEN

BACKGROUND: Celiac disease (CD) is an autoimmune enteropathy induced by dietary wheat gluten that can have serious consequences if not diagnosed and treated early. It is important to be familiar with other alterations associated with gluten ingestion due to the multiplicity of clinical presentations. OBJECTIVES: To describe the most common CD presentation patterns and alterations associated with gluten in children from the northwest region of Mexico, with an incipient knowledge of its prevalence. PATIENTS AND METHODS: Age, sex, family history, and gastrointestinal and extraintestinal symptoms were recorded in 24 patients within the time frame of 2006 to 2010. Biochemical and hematologic data were collected. Anti-gliadin and anti-transglutaminase antibodies were analyzed in all the cases, and haplotypes (HLA-DQ2/DQ8) and duodenal biopsy were evaluated in some of the cases. RESULTS: Of the 24 patients (14 girls and 10 boys), 13 presented with typical CD with symptoms of poor gastrointestinal absorption; 7 patients with a mean age of 5 years presented with atypical CD; 2 had disease onset with gastrointestinal and extraintestinal (neurologic) problems; and 2 with other gluten-related disorders. All of the patients had positive serology; 11/15 presented with HLA-DQ2/DQ8 and 4 with at least one allele; damaged mucosa was observed in the 6 biopsies taken. A third of the patients were anemic, 6 presented with an albumin value of<3.5g/dL, and 4 with mineral deficiencies. A total of 83% of the patients improved with a gluten-free diet. CONCLUSIONS: The presentation patterns were: 1) typical CD, 2) atypical CD, 3) CD with gastrointestinal and extraintestinal (neurologic) symptoms, and 4) gluten-related disorders other than CD.


Asunto(s)
Enfermedad Celíaca/epidemiología , Adolescente , Enfermedad Celíaca/patología , Enfermedad Celíaca/terapia , Preescolar , Femenino , Glútenes/inmunología , Antígenos HLA-DQ/análisis , Haplotipos , Humanos , Lactante , Absorción Intestinal , Mucosa Intestinal/patología , Masculino , México/epidemiología
6.
Rev Gastroenterol Mex (Engl Ed) ; 86(3): 287-304, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34144942

RESUMEN

Dietary fiber intake is one of the most influential and efficacious strategies for modulating the gut microbiota. Said fiber can be digested by the microbiota itself, producing numerous metabolites, which include the short-chain fatty acids (SCFAs). SCFAs have local and systemic functions that impact the composition and function of the gut microbiota, and consequently, human health. The aim of the present narrative review was to provide a document that serves as a frame of reference for a clear understanding of dietary fiber and its direct and indirect effects on health. The direct benefits of dietary fiber intake can be dependent on or independent of the gut microbiota. The use of dietary fiber by the gut microbiota involves several factors, including the fiber's physiochemical characteristics. Dietary fiber type influences the gut microbiota because not all bacterial species have the same capacity to produce the enzymes needed for its degradation. A low-fiber diet can affect the balance of the SCFAs produced. Dietary fiber indirectly benefits cardiometabolic health, digestive health, certain functional gastrointestinal disorders, and different diseases.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Bacterias , Fibras de la Dieta , Ácidos Grasos Volátiles , Humanos
7.
Res Vet Sci ; 85(1): 92-100, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17904172

RESUMEN

The aim of this study was to investigate the effects of dietary supplementation of sows with alpha-tocopherol acetate (ATA) and vitamin C on deposition of alpha-tocopherol (AT) in piglet lymphoid organs, such as bone marrow, thymus, and spleen at birth and at weaning, as well as on indicators of immune response in piglets. Sows were given the following treatment diets: control, vitamin C 10 g/day, ATA 500 mg/kg feed, and combined vitamins (ATA 500+Vit-C 10). Supplementation with vitamins started at the beginning of pregnancy and lasted until weaning at 21+/-3 days of age. AT was determined in colostrum, milk, piglet plasma (cord blood) and tissues at birth and on day 21. Immunoglobulins were measured in piglet plasma, milk, and colostrum. Lymphocyte proliferation in response to PHA and ConA was determined in sow and piglet blood. ATA supplementation resulted in a significant increase (P<0.001) in the AT content of colostrum, milk, piglet plasma, liver, thymus, bone marrow, and spleen at weaning. The AT content of colostrum and milk significantly (P<0.001) influenced the AT content of piglet plasma and tissues at weaning (day 21). Total Ig and IgG concentrations in piglet plasma were significantly increased in piglets given the combined vitamin treatment. No effect of AT supplementation was observed on IgG and IgA in colostrum and milk. In sows, vitamin C given alone significantly increased lymphocyte response to ConA and PHA; whereas, in piglets, there was no significant effect of treatments on lymphocyte response to PHA and ConA.


Asunto(s)
Ácido Ascórbico/farmacología , Calostro/química , Inmunidad Materno-Adquirida/efectos de los fármacos , Leche/química , Porcinos/inmunología , alfa-Tocoferol/análogos & derivados , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos/inmunología , Proliferación Celular , Dieta/veterinaria , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Femenino , Leucocitos Mononucleares/metabolismo , Embarazo , Tocoferoles , alfa-Tocoferol/farmacología
8.
Rev Gastroenterol Mex (Engl Ed) ; 83(2): 79-85, 2018.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29162372

RESUMEN

INTRODUCTION: Celiac disease (CD) is an autoimmune enteropathy associated with gluten ingestion. In extended families of celiac patients that live in close proximity of one another, shared genetic and environmental factors can predispose them to CD. AIM: The aim of this study was to provide evidence about the genetic and environmental factors involved in the development of CD in the extended family of a pediatric patient. METHODS: The medical history, environmental conditions, and participant weight, height, and peripheral blood samples were evaluated. The HLA-DQ2/DQ8 haplotypes were genotyped through qPCR testing and the IgA anti-gliadin and anti-transglutaminase antibodies were quantified using the ELISA test. RESULTS: Twelve close-living maternal relatives of the index case participated in the study. Eight of them presented with the HLA-DQ2 haplotype, inherited from the grandfather, and 7/12 and 9/12 were positive for IgA anti-gliadin and IgA anti-transglutaminase antibodies, respectively. The main intestinal symptoms stated by the participants were abdominal bloating, excess flatulence, constipation, and gastroesophageal reflux. The most frequent extra-intestinal symptoms were fatigue, stress, and anxiety. In addition, 6/13 participants had bronchial asthma. CONCLUSION: The extended family living in close proximity of one another shared a genetic predisposition, environmental conditions, and asthma, which could have predisposed them to celiac disease.


Asunto(s)
Asma/complicaciones , Enfermedad Celíaca/etiología , Ambiente , Predisposición Genética a la Enfermedad , Antígenos HLA-DQ/genética , Adulto , Asma/genética , Enfermedad Celíaca/diagnóstico , Niño , Familia , Femenino , Marcadores Genéticos , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
9.
Food Funct ; 9(1): 534-540, 2018 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-29260184

RESUMEN

Consumers with gluten-related disorders require gluten-free (GF) foods to avoid an immune response. Alternative to the use of non-gluten containing grains to prepare GF bread, the gluten reactivity has been greatly reduced using a proline specific cleavage enzyme, however, the gluten functionality was lost. The aim of this study was to evaluate the effect of adding an amaranth flour blend (AFB) to enzymatically modified wheat-flour proteins on dough functionality and to evaluate the immunoreactivity and acceptability of the prepared bread. First, wheat flour (20% w/v, substrate) was hydrolyzed using 8.4 U mg-1 protein Aspergillus niger prolyl-endopeptidase (AnPEP) for 8 h at 40 °C under constant agitation. Four types of breads were prepared with the same formulation except for the type of flour (14% w.b.): wheat flour (WF), WF-AFB unmodified not incubated, WF-AFB unmodified incubated and WF-AFB modified. The protein composition and free thiols were analyzed before and after amaranth addition, and the flour and bread proteins were run using SDS-PAGE and immune-detected in blots with IgA from celiac disease patients. The immunoreactive gluten content, specific volume and bread acceptability were evaluated. The polymeric proteins and free thiol groups of WF decreased after AnPEP treatment. The electrophoretic patterns of the modified flour and bread proteins were different and the IgA-immunodetection in blots was highly reduced, particularly for the higher molecular weight subunits. The addition of AFB to the modified wheat flour prepared using AnPEP improved the dough functionality by increasing the thiol groups and allowed the preparation of a sensorially acceptable bread with only 60 mg kg-1 immunoreactive gluten.


Asunto(s)
Amaranthus/química , Pan/análisis , Enfermedad Celíaca/inmunología , Endopeptidasas/química , Harina/análisis , Aditivos Alimentarios/análisis , Glútenes/química , Triticum/química , Adolescente , Adulto , Aspergillus niger/enzimología , Biocatálisis , Femenino , Proteínas Fúngicas/química , Glútenes/inmunología , Humanos , Inmunoglobulina A/inmunología , Masculino , Persona de Mediana Edad , Extractos Vegetales/análisis , Gusto , Triticum/inmunología , Adulto Joven
10.
Rev Gastroenterol Mex (Engl Ed) ; 83(4): 434-450, 2018.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30197183

RESUMEN

Celiac disease, celiac sprue, or gluten-sensitive enteropathy, is a generalized autoimmune disease characterized by chronic inflammation and atrophy of the small bowel mucosa. It is caused by dietary exposure to gluten and affects genetically predisposed individuals. In Mexico, at least 800,000 are estimated to possibly have the disease, prompting the Asociación Mexicana de Gastroenterología to summon a multidisciplinary group of experts to develop the "Clinical guidelines on the diagnosis and treatment of celiac disease in Mexico" and establish recommendations for the medical community, its patients, and the general population. The participating medical professionals were divided into three working groups and were given the selected bibliographic material by the coordinators (ART, LUD, JMRT), who proposed the statements that were discussed and voted upon in three sessions: two voting rounds were carried out electronically and one at a face-to-face meeting. Thirty-nine statements were accepted, and once approved, were developed and revised by the coordinators, and their final version was approved by all the participants. It was emphasized in the document that epidemiology and risk factors associated with celiac disease (first-degree relatives, autoimmune diseases, high-risk populations) in Mexico are similar to those described in other parts of the world. Standards for diagnosing the disease and its appropriate treatment in the Mexican patient were established. The guidelines also highlighted the fact that a strict gluten-free diet is essential only in persons with confirmed celiac disease, and that the role of gluten is still a subject of debate in relation to nonceliac, gluten-sensitive patients.


Asunto(s)
Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/terapia , Dieta Sin Gluten , Enfermedad Celíaca/dietoterapia , Enfermedad Celíaca/genética , Susceptibilidad a Enfermedades , Humanos , México , Cooperación del Paciente
11.
Ann Ig ; 18(6): 467-79, 2006.
Artículo en Italiano | MEDLINE | ID: mdl-17228605

RESUMEN

In the Lazio Region, it has been put into effect a plan of clinical Risk Management for the Breast Cancer Screening Regional Program (BCSP), involving all of the 12 Local Health Units and the Public Health Agency of Lazio (ASP). Being the BCSP a health care service, it consists of a perfect integration of health care structures, professionals and skills working for the citizens. This program originates from an unexpressed health need and leads to a evidence-based health benefit. The BCSP provides free breast screening for 700,000 women aged between 50 and 69 in the Lazio region; the Public Health Agency carries out the clinical governance of the BCSP The prevention of errors and incidents represents a fundamental basis of governance: it is a contribution to the achievement of efficacy in breast cancer screening. The BCSP deals with screening incidents from a systemic point of view and actively involves several Local Health Units staff going through each step of the whole patient's clinical path, from the identification of the target population, to the oncological treatment of positive cases. The programme is an integration of different tools: literature research, process analysis using the HFMEA methodology and reporting system. The results reached so far are the following: the regional severity rating scale, the regional Master-List of possible adverse events, occurrence and detection rating scale.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Mamografía , Tamizaje Masivo/métodos , Gestión de Riesgos , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Medicina Basada en la Evidencia , Femenino , Humanos , Italia , Tamizaje Masivo/organización & administración , Persona de Mediana Edad , Proyectos Piloto , Salud Pública , Índice de Severidad de la Enfermedad
12.
Diagn Interv Imaging ; 97(9): 883-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27211021

RESUMEN

PURPOSE: The purpose of this study was to evaluate the diagnostic performance of sonoelastography by using real-time strain ratio and qualitative 5-stage elasticity score in breast lesions for which ultrasonographic evaluation suggested malignancy (BI-RADS 4 and 5 lesions). MATERIALS AND METHODS: From January 2012 to October 2012, 168 solid breast lesions were investigated using sonoelastography. The strain ratios and the elasticity scores were calculated. Final diagnosis was made by histopathological analysis. Areas under the curve and cut-off points were used to assess diagnostic performance of sonoelastography. The sensitivity, and specificity of these two imaging tests were compared using McNemar test. RESULTS: The strain ratios of malignant lesions (mean value=9.3) and benign lesions (mean value=3.75) were significantly different (P<0.00001). Using a cut-off value of 4.79, strain ratio had 78.8% sensitivity, 78.3% specificity, 86.7% positive predictive value (PPV) and 67% negative predictive value (NPV). Using a 5-stage elasticity score system, a 83.3% sensitivity, 74.6% specificity, 85.7% PPV and 71.0% NPV were obtained. CONCLUSION: Our study indicates that sonoelastography has good clinical value to discriminate between benign and malignant breast lesions. There are no differences in terms of diagnostic performance in differentiating malignant from benign lesions when strain ratio or color scoring are used alone. However the diagnostic performance is increased when strain ratio and color scoring evaluations are used in combination.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de la Mama/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Adulto Joven
13.
Biochim Biophys Acta ; 1149(1): 55-62, 1993 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-8318531

RESUMEN

The influence of phosphatidylserine (PS) liposome size on their capacity to activate and bind purified glucosylceramidase was investigated. Gel filtration and flotation experiments showed that large unilamellar vesicles (LUV) of either pure PS or PS in admixture with phosphatidylcholine (PC) are unable to tightly bind purified glucosylceramidase, and thus, to fully stimulate its activity. By contrast, small unilamellar vesicles (SUV) of PS adsorb glucosylceramidase can either be favoured or inhibited by factors affecting the bilayer curvature of PS liposomes. An increase of PS vesicle size induced by a fusogenic agent such as poly(ethylene glycol) (PEG), decreased enzyme binding and activity. On the contrary, the reduction of PS LUV size by sonication increased their stimulating ability. Enzyme association with PS SUV is reversible. In fact, glucosylceramidase bound to PS SUV was released from the lipid surface when the SUV were transformed into larger vesicles by PEG; dissociation from the vesicles resulted in a dramatic decrease of enzyme activity. Although PS LUV are unable to reconstitute glucosylceramidase, their association with oleic acid (OA) promotes the interaction with glucosylceramidase. This phenomenon is best explained in terms of OA-induced surface defects of PS LUV, with consequent exposure of the more hydrophobic part of the membrane and hence the improved binding of hydrophobic region/s of glucosylceramidase. Our data indicate that the physical organization of the PS-containing liposomes is of critical importance of glucosylceramidase reconstitution. The observation that physical changes of the lipid surface can markedly affect the enzyme activity offers a new approach to the study of glucosylceramidase regulation.


Asunto(s)
Glucosilceramidasa/metabolismo , Membrana Dobles de Lípidos/metabolismo , Liposomas/metabolismo , Fosfatidilserinas/metabolismo , Activación Enzimática , Humanos , Membrana Dobles de Lípidos/química , Liposomas/química , Ácido Oléico , Ácidos Oléicos/farmacología , Tamaño de la Partícula
14.
FEBS Lett ; 336(1): 159-62, 1993 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-8262201

RESUMEN

The function of saposin C (Sap C), a glucosylceramidase activator protein, in the enzyme stimulation by phosphatidylserine (PS) liposomes has been investigated. Using gel filtration experiments evidence was obtained for Sap C binding to PS large unilamellar vesicles (LUV) but not to glucosylceramidase. PS LUV, which by themselves are unable to tightly bind and stimulate the enzyme, acquire the capacity to also bind the enzyme after interaction with Sap C, making it express its full activity. Our results indicate that the primary step in the Sap C mode of action resides in its association with PS membranes; in turn, this association promotes the interaction between the membranes and glucosylceramidase.


Asunto(s)
Glucosilceramidasa/metabolismo , Glicoproteínas/fisiología , Fosfatidilserinas/metabolismo , Activación Enzimática , Humanos , Liposomas , Saposinas
15.
FEBS Lett ; 349(2): 181-6, 1994 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8050562

RESUMEN

We have previously shown that saposin C (Sap C), a glucosylceramidase activator protein, interacts with phosphatidylserine (PS) large unilamellar vesicles (LUV), promoting the glucosylceramidase binding to the bilayer [(1993) FEBS Lett. 336, 159-162]. In the present paper the consequences of the Sap C interaction on the lipid organization of the vesicles are reported. It was found that Sap C perturbs the PS bilayer as shown by the release of an encapsulated fluorescent dye. Three different procedures, resonance energy transfer, gel filtration and electron microscopy, indicated that the activator protein is also able to make PS liposomes fuse. The effects of Sap C on PS vesicles were observed at low but not at neutral pH. The lipid composition of the bilayer also affected the Sap C-induced destabilization; in fact, the presence of PS in mixed LUV was essential for significant leakage to occur. These results demonstrate for the first time that Sap C is a protein capable of destabilizing and fusing acidic phospholipid-containing membranes in a pH-dependent fashion.


Asunto(s)
Glicoproteínas/metabolismo , Membrana Dobles de Lípidos/metabolismo , Fosfatidilserinas/metabolismo , beta-Glucosidasa/metabolismo , Animales , Bovinos , Cromatografía en Gel , Activación Enzimática , Glicoproteínas/química , Membrana Dobles de Lípidos/química , Liposomas , Fluidez de la Membrana , Fusión de Membrana , Fosfatidilserinas/química , Saposinas , beta-Glucosidasa/química
16.
J Med Microbiol ; 47(1): 29-37, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9449947

RESUMEN

Lectins of various specificities were examined for interaction with strains of oral streptococci of various species. The lectins were capable of binding galactose, N-acetylgalactosamine, glucose, N-acetylglucosamine, mannose, fucose and sialic acid. Lectin reactivities were strain-dependent in that some members of a species, but not others, could be aggregated by certain lectins. Proteolysis and extraction with hot water, guanidine hydrochloride and sodium dodecyl sulphate tended to increase the reactivity of the streptococci with lectins but did not change the recognition patterns of the bacteria. Sonication, in contrast, tended to reduce the ability of streptococci to be agglutinated by lectins. Furthermore, lectin reactivities were dependent on the growth conditions, as evidenced by changes in lectin titres following streptococcal growth in sub-inhibitory concentrations of citrate, fluoride or antibiotics. It is likely that lectins could be useful tools for epidemiological studies and to probe strain-dependent and growth-dependent surface characteristics of viridans streptococci.


Asunto(s)
Lectinas/metabolismo , Boca/microbiología , Streptococcus/metabolismo , Pruebas de Aglutinación , Antibacterianos/farmacología , Metabolismo de los Hidratos de Carbono , Citratos/farmacología , Medios de Cultivo , Humanos , Oxacilina/farmacología , Penicilinas/farmacología , Citrato de Sodio , Fluoruro de Sodio/farmacología , Sonicación , Streptococcus/efectos de los fármacos , Streptococcus/crecimiento & desarrollo , Estreptomicina/farmacología
17.
Life Sci ; 59(23): 1951-60, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8950294

RESUMEN

Gliadin-protein interaction and its relationship to the pathogenesis hypotheses of celiac disease was investigated. Wheat germ agglutinin was not immunodetected in gliadin preparations. Peptic-tryptic gliadin digest was used to study the gliadin-protein interactions by crossed immunoelectrophoresis and affinity blotting. Biotinylated gliadin digest interacted with IgG and bovine serum albumin but not with several glycoproteins. Since albumin and IgG light chains are not glycosylated, this interaction is not lectin-like, neither completely immunological because of recognition of the IgG Fc fraction. Immobilized and boiled IgG was not recognized by gliadin digest as a lectin. Gliadin digest fractions from T-gel chromatography reduced the fluorescence intensity of cis-parinaric acid bound to albumin. The gliadin-protein interaction is not lectin-like or completely immunological but hydrophobic. Hydrophobicity of gliadins may contribute to the pathogenic events that result in celiac disease.


Asunto(s)
Enfermedad Celíaca/metabolismo , Gliadina/metabolismo , Lectinas/metabolismo , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Humanos , Hidrólisis , Unión Proteica , Aglutininas del Germen de Trigo/metabolismo
18.
Mutat Res ; 423(1-2): 171-81, 1999 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-10029694

RESUMEN

In this paper, the molecular interactions in isolated mammalian nuclei of three ruthenium complexes, which are putative antineoplastic chemotherapeutic agents effective in reducing metastatic tumours in vivo, have been investigated and compared with the well-known antitumour drug CDDP (cis-diamminedichloroplatinum). The compounds studied are: Natrans-RuCl4(DMSO)Imidazole (NAMI), Natrans-RuCl4(DMSO)Oxazole (NAOX) and Natrans-RuCl4(TMSO)- Isoquinoline (TEQU). This study shows that the drugs bind to DNA but induce few, if any, DNA interstrand crosslinks, which are considered as the main biological lesions involved in the cytotoxic activity of several already known antitumour drugs, whilst in the same experimental conditions, CDDP is confirmed to induce them. On the other hand, proteins appear to be an important target in the cell for these drugs, since proteins-DNA crosslinks are shown to be induced by the complexes. Moreover, we investigated Ru complexes for their direct cytotoxicity on V79 cells in culture, showing that two of them (NAMI and NAOX) do not significantly reduce the cloning efficiency of the cells even at concentrations as high as 2-3 mg/ml: only TEQU both reduces cloning efficiency and induces a significant number of mutants in V79 cells in culture.


Asunto(s)
Núcleo Celular/efectos de los fármacos , Dimetilsulfóxido/análogos & derivados , Compuestos Organometálicos/metabolismo , Compuestos Organometálicos/toxicidad , Rutenio/metabolismo , Rutenio/toxicidad , Animales , Línea Celular , Cricetinae , ADN/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Dimetilsulfóxido/metabolismo , Dimetilsulfóxido/toxicidad , Fibroblastos , Humanos , Hipoxantina Fosforribosiltransferasa/genética , Pulmón , Sustancias Macromoleculares , Pruebas de Mutagenicidad , Compuestos de Rutenio
19.
J Biochem Biophys Methods ; 27(3): 169-80, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8258637

RESUMEN

Affinity methods were used to characterize selective interactions of alkaline phosphatase (ALP) isoenzymes from different dog tissues with lectins. Specific lectins were used to identify liver, intestinal and steroid-induced ALP isoenzymes in serum from dogs with Cushing syndrome or steroid-treated dogs. For the first approach, 12 lectins were assayed by affinity dots. Selective interactions were found among wheat germ agglutinin (WGA), jacalin, con A (concanavalin A) and Helix pomatia agglutinin (HPA) and several ALP-containing samples. These four reactive lectins were assayed by line electrophoresis with lectins in holes. A strong reactivity of con A with all isoenzymes was found, although the patterns were different. WGA interacted with intestinal, bone marrow extracts and Cushing syndrome serum. Jacalin changed the electrophoretic patterns of intestinal and liver ALP, and Cushing serum. Finally, by crossed electrophoresis with lectins in gels, it was possible to distinguish among hepatic or intestinal ALPs and the steroid-induced isoenzyme in serum. Affinity electrophoresis with lectins provided a clear separation and identification of the different dog ALP isoenzymes.


Asunto(s)
Fosfatasa Alcalina/análisis , Isoenzimas/análisis , Animales , Cromatografía de Afinidad/métodos , Perros , Electroforesis en Gel de Agar/métodos , Immunoblotting/métodos , Lectinas
20.
Lipids ; 34(6): 639-42, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10405979

RESUMEN

One of the few sources of long-chain n-3 polyunsaturated fatty acids is fish oil, but considerable variation may exist according to species and season. In this study, the fatty acid profiles of sardine oils from Sardinops sagax caeruleus of the Gulf of California, Mexico, were evaluated in three seasonal catch periods. Oil quality was also evaluated by peroxide and free acid values. The most abundant fatty acids found in the oils were palmitic acid (19.3%), oleic acid (14.3%), eicosapentaenoic acid (EPA, 20.4%), and docosahexaenoic acid (DHA, 12.2%). There was no significant difference in the composition and quality among the six reduction plants where the samples were obtained. However, a significant difference in the proportion of EPA and DHA in one of the catch seasons analyzed was observed.


Asunto(s)
Ácidos Grasos/análisis , Aceites de Pescado/química , Estaciones del Año , Cromatografía de Gases , Aceites de Pescado/normas , Control de Calidad
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