Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Clin Epigenetics ; 14(1): 133, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36284309

RESUMEN

BACKGROUND: Penile cancer is one of the most aggressive male tumors. Although it is preventable, the main etiologic causes are lifestyle behaviors and viral infection, such as human papillomavirus (HPV). Long-term epigenetic changes due to environmental factors change cell fate and promote carcinogenesis, being an important marker of prognosis. We evaluated epidemiological aspects of penile squamous cell carcinoma (SCC) and the prevalence of HPV infection using high-risk HPV (hrHPV) and p16INK4A expression of 224 participants. Global DNA methylation was evaluated through 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). RESULTS: The incidence of HPV was 53.2% for hrHPV and 22.32% for p16INK4a. hrHPV was not related to systemic or lymph node metastasis and locoregional recurrence, nor influenced the survival rate. P16INK4a seems to be a protective factor for death, which does not affect metastasis or tumor recurrence. Lymph node and systemic metastases and locoregional recurrence increase the risk of death. An increased 5mC mark was observed in penile SCC regardless of HPV infection. However, there is a reduction of the 5hmC mark for p16INK4a + (P = 0.024). Increased 5mC/5hmC ratio (> 1) was observed in 94.2% of penile SCC, irrespective of HPV infection. Despite the increase in 5mC, it seems not to affect the survival rate (HR = 1.06; 95% CI 0.33-3.38). CONCLUSIONS: P16INK4a seems to be a good prognosis marker for penile SCC and the increase in 5mC, an epigenetic mark of genomic stability, may support tumor progression leading to poor prognosis.


Asunto(s)
Alphapapillomavirus , Carcinoma de Células Escamosas , Infecciones por Papillomavirus , Neoplasias del Pene , Masculino , Humanos , Neoplasias del Pene/genética , Neoplasias del Pene/epidemiología , Neoplasias del Pene/patología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/epidemiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Pronóstico , 5-Metilcitosina , Metilación de ADN , Recurrencia Local de Neoplasia/genética , Papillomaviridae/genética , Carcinoma de Células Escamosas/metabolismo , Alphapapillomavirus/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Epigénesis Genética , ADN Viral
2.
Support Care Cancer ; 29(7): 3521-3530, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33155091

RESUMEN

BACKGROUND: Emotional distress associated with genetic testing for hereditary breast and ovarian cancer syndrome (HBOC) is reported to interfere with adherence to treatment and prophylactic measures and compromise quality of life. OBJECTIVES: To determine levels of anxiety, depression, and quality of life in patients tested for pathogenic BRCA1/2 mutations and identify risk factors for the development of adverse psycho-emotional effects. METHODS: Cross-sectional observational trial involving 178 breast or ovarian cancer patients from a referral cancer hospital in Northeastern Brazil. Information was collected with the Hospital Anxiety and Depression Scale (HADS) and the World Health Organization (WHO) Quality of Life (QoL) questionnaire (WHOQOL-BREF). RESULTS: Patients suspected of HBOC had higher levels of anxiety than depression. The presence of (probably) pathogenic BRCA1/2 mutations did not affect levels of anxiety and depression. High schooling, history of psychiatric disease, and use of psychotropic drugs were directly associated with high anxiety. High schooling was too inversely associated with QoL as such a breast tumor. Anxiety and depression were directly correlated and both reduced significantly QoL. CONCLUSION: Our results highlight the importance of psychological support and screening of risk factors for anxiety and depression and low QoL in HBOC patients at the time of testing.


Asunto(s)
Ansiedad/psicología , Depresión/psicología , Pruebas Genéticas/métodos , Síndrome de Cáncer de Mama y Ovario Hereditario/psicología , Calidad de Vida/psicología , Estudios Transversales , Femenino , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Humanos , Persona de Mediana Edad , Encuestas y Cuestionarios
3.
Artículo en Inglés | MEDLINE | ID: mdl-32981869

RESUMEN

OBJECTIVES: To describe a patient with BRCA1 mutation, mucoepidermoid parotid, multiple breasts, and thyroid cancers. CASE REPORT: A women was diagnosed at 33-years-age with a triple-negative breast cancer (right breast), at 43-years-age with a triple-negative breast cancer in left breast and at 53-years-age with a primary papillary-thyroid carcinoma. At 55-years-age, she was diagnosed with a primary mucoepidermoid carcinoma in right parotid, and concomitantly, her right nipple was affected by Paget's disease and a recurrent carcinoma in right breast (HR + /HER2 = 3 +). At 57-years-age, after the recurrence of a triple-negative breast cancer (left breast), a geneticist evaluated the patient's family history, including one stomach, one non-smoking-related lung, and two smoking-related laryngeal cancers. Genetic testing revealed a BRCA1 mutation (Chr17:41:251.867). The patient's daughter (a non-cancer patient) tested negative for the mutation. Both remain under medical supervision. CONCLUSIONS: We suggest that BRCA1 mutations are associated with non-breast and non-ovarian cancers such as salivary gland cancer.


Asunto(s)
Neoplasias de la Mama , Carcinoma Mucoepidermoide , Neoplasias de la Parótida , Adulto , Proteína BRCA1 , Neoplasias de la Mama/genética , Carcinoma Mucoepidermoide/genética , Carcinoma Mucoepidermoide/cirugía , Femenino , Humanos , Persona de Mediana Edad , Mutación , Recurrencia Local de Neoplasia , Glándula Parótida , Neoplasias de la Parótida/genética
4.
Anim Reprod ; 15(Suppl 1): 691-702, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-36249850

RESUMEN

Molecular components of sperm and in the media surrounding them influence male fertility. In this regard, seminal plasma proteins and metabolites modulate various reproductive events, including sperm motility and capacitation, cell protection, acrosome reaction, fertilization and embryonic development. Empirical associations between seminal proteins and metabolites and fertility indicate that these molecules are potential molecular markers of male reproductive status in cattle and other species.

5.
Arch Biochem Biophys ; 543: 31-9, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24361256

RESUMEN

Lectins are comprised of a large family of proteins capable of the specific and reversible recognition of carbohydrates. Legume lectins, the most studied plant lectins, show high structural similarity, but with modifications that imply a variation in the intensity of some biological activities. In this work, the primary and tertiary structures of Canavalia grandiflora (ConGF) were determined. ConGF, a lectin isolated from C. grandiflora seeds, is able to induce relaxant activity in rat aortic rings. The complete sequence of ConGF comprises 237 amino acids. This particular protein has primary sequence variations commonly found in lectins from Dioclea and Canavalia genera. The protein structure was solved at 2.3 Å resolution by X-ray crystallography. An X-Man molecule was modeled into the carbohydrate recognition domain. Still, ConGF (30 and 100 µg mL(-1)) elicited 25% of vasorelaxation (IC50=34.48 ± 5.07 µg mL(-1)) in endothelialized aortic rings. A nonselective inhibitor of nitric oxide blocked ConGF relaxant effect, showing mediation by nitric oxide. Key distances between ConGF carbohydrate recognition domain residues were determined in order to explain this effect, in turn revealing some structural aspects that could differentiate lectins from the Canavalia genera with respect to different efficacy in vasorelaxant effect.


Asunto(s)
Lectinas de Plantas/química , Lectinas de Plantas/farmacología , Vasodilatadores/química , Vasodilatadores/farmacología , Secuencia de Aminoácidos , Animales , Sitios de Unión , Técnicas In Vitro , Masculino , Manosa/química , Manosa/metabolismo , Espectrometría de Masas , Modelos Moleculares , Datos de Secuencia Molecular , Lectinas de Plantas/metabolismo , Estabilidad Proteica , Estructura Terciaria de Proteína , Ratas , Ratas Wistar , Análisis de Secuencia , Relación Estructura-Actividad , Vasodilatadores/metabolismo
6.
Int J Biochem Cell Biol ; 45(4): 807-15, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23353644

RESUMEN

Lectins from Diocleinae subtribe belong to the family of legume lectins and are characterized by high identity between their amino acids sequences. It has been shown that punctual differences in amino acid sequences, such as one single amino acid or an alternative conformation, represent changes in biological activities caused by these lectins. Therefore, a more detailed understanding of three-dimensional structures of these proteins is essential for accurate analyzing the relationship between structure and function. In this study lectins purified from the seeds of Dioclea violacea (DVL) and Dioclea rostrata (DRL) were compared with regard to crystal structure and vasorelaxant properties. Differences in structure of lectins were found to be reflected in differences in vasorelaxant effects based on their high specificity and selectivity for cell glycans. Binding activity was related to the position of specific residues in the carbohydrate recognition domain (CRD). DVL complexed structure was solved by X-ray crystallography and was compared to native DVL and DRL. Therefore, DVL was co-crystallized with X-Man, and a molecular modeling with X-Man complexed with DVL was done to compare the complexed and native forms adjusted fit. The relatively narrow and deep CRD in DVL promotes little interaction with carbohydrates; in contrast, the wider and shallower CRD in DRL favors interaction. This seems to explain differences in the level of relaxation induced by DVL (43%) and DRL (96%) in rat aortic rings.


Asunto(s)
Dioclea/química , Lectinas de Plantas/química , Lectinas de Plantas/farmacología , Vasodilatadores/química , Vasodilatadores/farmacología , Secuencia de Aminoácidos , Animales , Aorta/efectos de los fármacos , Aorta/fisiología , Cristalografía por Rayos X , Técnicas In Vitro , Masculino , Manosa/química , Manosa/metabolismo , Simulación del Acoplamiento Molecular , Datos de Secuencia Molecular , Lectinas de Plantas/metabolismo , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Ratas , Ratas Wistar , Especificidad de la Especie , Vasodilatadores/metabolismo
7.
Rapid Commun Mass Spectrom ; 26(7): 811-8, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22368061

RESUMEN

RATIONALE: Lectins are a family of proteins capable of deciphering the glycan code. Several authors have published works about crystallization and mass spectrometry analyses of ConA-like lectins. However, mass spectrometry has never been used to characterize lectin crystal content. In this study, Canavalia grandiflora lectin (ConGF), a ConA-like lectin, was crystallized, part of its primary structure sequenced and the pro-inflammatory activity evaluated. In addition, the crystal content was analyzed by mass spectrometry. METHODS: ConGF was crystallized in the presence of X-Man by hanging-drop vapor diffusion at 293 K and the protein crystal content was analyzed by electrospray ionization in a SYNAPT HDMS mass spectrometer. Partial sequence was obtained by protein digestion with several proteolytic enzymes and the peptides sequenced by liquid chromatography/tandem mass spectrometry (LC/MS/MS). The pro-inflammatory potential of ConGF was also evaluated in the model of rat paw edema. RESULTS: The protein crystals consist of mature α chain and ß and γ fragments measuring 25 612 ± 2 Da, 12 962 ± 2 Da and 12 667 ± 2 Da, respectively. The crystal belongs to the orthorhombic space group I222 (unit cell parameters: a = 67.70, b = 55.90, c = 107.46 Å), assuming a monomer in the asymmetric unit. The solvent content was calculated as 43.50% and the protein content as 2.5 µg. Furthermore, a significant part of the primary structure (65.8%) was determined by mass spectrometry. CONCLUSIONS: As far as we know this is the first report of lectin crystal content characterized by mass spectrometry. Like other ConA-like lectins, GonGF induced paw edema however differing in potency and duration. The observed pro-inflammatory activity suggests that ConGF might be a useful tool in the study of inflammation processes and structure/function relationships.


Asunto(s)
Edema/inducido químicamente , Inflamación/inducido químicamente , Lectinas de Plantas/química , Espectrometría de Masas en Tándem/métodos , Difracción de Rayos X/métodos , Secuencia de Aminoácidos , Animales , Miembro Posterior , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Filogenia , Lectinas de Plantas/farmacología , Ratas , Ratas Wistar , Semillas/química , Alineación de Secuencia
8.
Biochimie ; 94(2): 525-32, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21924319

RESUMEN

The crystal structure and pro-inflammatory property of a lectin from the seeds of Dioclea wilsonii (DwL) were analyzed to gain a better understanding of structure/function relationships of Diocleinae lectins. Following crystallization and structural determination by standard molecular replacement techniques, DwL was found to be a tetramer based on PISA analysis, and composed by two metal-binding sites per monomer and loops which are involved in molecular oligomerization. DwL presents 96% and 99% identity with two other previously described lectins of Dioclea rostrata (DRL) and Dioclea grandiflora (DGL). DwL differs structurally from DVL and DRL with regard to the conformation of the carbohydrate recognition domain and related biological activities. The structural analysis of DwL in comparison to other Diocleinae lectins can be related to the differences in the dose-dependent pro-inflammatory effect elicited in Wistar rats, probably via specific interactions with mast cells complex carbohydrate, resulting in significant paw edema. DwL appears to be involved in positive modulation of mast cell degranulation via recognition of surface carbohydrates. Since this recognition is dependent on site volume and CRD configuration, edematogenesis mediated by resident cells varies in potency and efficacy among different Diocleinae lectins.


Asunto(s)
Degranulación de la Célula/efectos de los fármacos , Dioclea/química , Edema/inmunología , Mastocitos/inmunología , Lectinas de Plantas/farmacología , Animales , Sitios de Unión , Degranulación de la Célula/inmunología , Cristalografía por Rayos X , Relación Dosis-Respuesta Inmunológica , Edema/inducido químicamente , Edema/patología , Miembro Posterior , Mastocitos/efectos de los fármacos , Mastocitos/patología , Modelos Moleculares , Tamaño de los Órganos/efectos de los fármacos , Lectinas de Plantas/química , Lectinas de Plantas/aislamiento & purificación , Unión Proteica , Multimerización de Proteína , Estructura Terciaria de Proteína , Ratas , Ratas Wistar , Semillas/química , Homología de Secuencia de Aminoácido , Termodinámica
9.
Molecules ; 16(6): 5087-103, 2011 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-21694673

RESUMEN

DwL, a lectin extracted from the seeds of Dioclea wilsonii, is a metalloprotein with strong agglutinating activity against rabbit and ABO erythrocytes, inhibited by glucose and mannose. DwL was purified by affinity chromatography on a Sephadex G-50 column and ion exchange chromatography on a HiTrap SP XL column. SDS-PAGE revealed three electrophoretic bands corresponding to the α (25,634 ± 2 Da), ß (12,873 ± 2 Da) and γ (12,779 ± 2 Da) chains. Protein sequencing was done by Tandem Mass Spectrometry. The primary sequence featured 237 amino acids and was highly homologous to other reported Diocleinae lectins. A complete X-ray dataset was collected at 2.0 Å for X-Man-complexed DWL crystals produced by the vapor diffusion method. The crystals were orthorhombic and belonged to the space group I222, with the unit-cell parameters a = 59.6, b = 67.9 and c = 109.0 Å. DWL differed in potency from other ConA-like lectins and was found to induce neutrophil migration in rats, making it particularly useful in structural/functional studies of this class of proteins.


Asunto(s)
Dioclea/química , Mediadores de Inflamación/química , Lectinas de Plantas/química , Semillas/química , Secuencia de Aminoácidos , Animales , Movimiento Celular/efectos de los fármacos , Secuencia Conservada , Cristalización , Eritrocitos/efectos de los fármacos , Humanos , Mediadores de Inflamación/aislamiento & purificación , Mediadores de Inflamación/farmacología , Datos de Secuencia Molecular , Neutrófilos/efectos de los fármacos , Lectinas de Plantas/aislamiento & purificación , Lectinas de Plantas/farmacología , Estabilidad Proteica , Conejos , Ratas , Ratas Wistar , Alineación de Secuencia
10.
Biochem Biophys Res Commun ; 408(4): 566-70, 2011 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-21530490

RESUMEN

Diocleinae lectins are highly homologous in their primary structure which features metal binding sites and a carbohydrate recognition domain (CRD). Differences in the biological activity of legume lectins have been widely investigated using hemagglutination inhibition assays, isothermal titration microcalorimetry and co-crystallization with mono- and oligosaccharides. Here we report a new lectin crystal structure (ConBr) extracted from seeds of Canavalia brasiliensis, predict dimannoside binding by docking, identify the α-aminobutyric acid (Abu) binding pocket and compare the CRD of ConBr to that of homologous lectins. Based on the hypothesis that the carbohydrate affinity of lectins depends on CRD configuration, the relationship between tridimensional structure and endothelial NO synthase activation was used to clarify differences in biological activity. Our study established a correlation between the position of CRD amino acid side chains and the stimulation of NO release from endothelium.


Asunto(s)
Canavalia/metabolismo , Óxido Nítrico Sintasa de Tipo III/química , Lectinas de Plantas/química , Carbohidratos , Cristalografía por Rayos X , Activación Enzimática , Conformación Proteica
11.
Artículo en Inglés | MEDLINE | ID: mdl-19255467

RESUMEN

Plant lectins are the most studied group of carbohydrate-binding proteins. Despite the high similarity between the members of the Diocleinae subtribe (Leguminosae) group, they present differing biological activities. Canavalia boliviana lectin (Cbol) was purified using a Sephadex G-50 column and crystallized in the presence of X-Man by hanging-drop vapour diffusion at 293 K. After optimization, crystals suitable for diffraction were obtained under the condition 0.1 M HEPES pH 7.5 and 3.0 M sodium formate. The crystal belonged to the monoclinic space group C2, with unit-cell parameters a = 126.70, b = 66.64, c = 64.99 A, alpha = 90.0, beta = 120.8, gamma = 90.0 degrees . Assuming the presence of a dimer in the asymmetric unit, the solvent content was estimated to be about 46%. A complete data set was collected at 1.5 A resolution.


Asunto(s)
Canavalia/química , Lectinas de Plantas/química , Semillas/química , Cromatografía de Afinidad , Cristalización , Cristalografía por Rayos X , Electroforesis en Gel de Poliacrilamida , Lectinas de Plantas/análisis
12.
Artículo en Inglés | MEDLINE | ID: mdl-16511292

RESUMEN

Lectins from the Diocleinae subtribe (Leguminosae) are highly similar proteins that promote various biological activities with distinctly differing potencies. The structural basis for this experimental data is not yet fully understood. Dioclea rostrata lectin was purified and crystallized by hanging-drop vapour diffusion at 293 K. The crystal belongs to the orthorhombic space group I222, with unit-cell parameters a = 61.51, b = 88.22, c = 87.76 A. Assuming the presence of one monomer per asymmetric unit, the solvent content was estimated to be about 47.9%. A complete data set was collected at 1.87 A resolution.


Asunto(s)
Fabaceae/química , Lectinas de Plantas/química , Semillas/química , Cristalización , Cristalografía por Rayos X , Lectinas de Plantas/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA