Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
1.
PLoS One ; 19(5): e0302854, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38722950

RESUMEN

For management efforts to succeed in Caribbean fisheries, local fishers must support and be willing to comply with fishing regulations. This is more likely when fishers are included in a stock assessment process that utilizes robust scientific evidence, collected in collaboration with fishers, to evaluate the health of fish stocks. Caribbean parrotfishes are important contributors to coral reef ecosystem health while also contributing to local fisheries. Scientifically robust stock assessments require regional species-specific information on age-based key life history parameters, derived from fish age estimates. Evaluation of the accuracy of age estimation methods for fish species is a critical initial step in managing species for long-term sustainable harvest. The current study resulted from a collaborative research program between fish biologists and local fishers investigating age, growth, and reproductive biology of the seven parrotfish species landed in U.S. Caribbean fisheries; specifically, we validated age estimation for stoplight parrotfish Sparisoma viride and queen parrotfish Scarus vetula. This is the first study to directly validate age estimation for any parrotfish species through analysis of Δ14C from eye lens cores. Our age estimation validation results show that enumeration of opaque zones from thin sections of sagittal otoliths for a Sparisoma and a Scarus species provides accurate age estimates. The oldest stoplight parrotfish and queen parrotfish in the Δ14C age estimation validation series were 14 y and 16 y; while the oldest stoplight parrotfish and queen parrotfish we aged to-date using the Δ14C validated age estimation method were 20 y and 21 y, respectively. Fish longevity (maximum age attained/life span) is a key life history parameter used for estimation of natural mortality, survivorship, and lifetime reproductive output. Past reviews on parrotfishes from the Pacific and Atlantic concluded that most Caribbean/western Atlantic parrotfish species are relatively short-lived with estimated maximum ages ranging from 3-9 y. However, information from our collaborative research in the U.S. Caribbean combined with recently published age estimates for Brazilian parrotfish species indicate that many western Atlantic parrotfishes are relatively long-lived with several species attaining maximum ages in excess of 20 y.


Asunto(s)
Explotaciones Pesqueras , Longevidad , Animales , Perciformes/crecimiento & desarrollo , Perciformes/fisiología , Conservación de los Recursos Naturales/métodos , Región del Caribe , Datación Radiométrica/métodos , Océano Atlántico
2.
J Fish Biol ; 101(6): 1557-1568, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36181378

RESUMEN

Our understanding of fish life-history strategies is informed by key biological processes, such as growth, survival/mortality, recruitment and sexual maturation, used to characterize fish stocks (populations). Characterizing the life-history traits of fish populations requires the application of accurate age estimation for managed species. Grey triggerfish Balistes capriscus and queen triggerfish Balistes vetula are important reef-associated species for commercial and recreational fisheries in the Atlantic Ocean. Both species exhibit a unique reproductive strategy for large-bodied fisheries-targeted reef fishes in that they are nesting benthic spawners and invest substantial energy in defence and care of their benthic nests and fertilized eggs. Until recently, our understanding of the life-history strategies of triggerfishes assumed the main method used to obtain age estimates, increments counted from thin sections of the first dorsal spine, provided an accurate characterization of population age-based parameters. However, results from bomb radiocarbon validation studies on the two Balistes species demonstrated that spines do not provide accurate ages, but sagittal otoliths do. The main goal of the current study was to provide an updated understanding for triggerfish life-history strategies by using otolith-based age estimates to characterize population age structure and growth for grey triggerfish and queen triggerfish from waters of the south-eastern U.S. Atlantic. The current study is the first to report on sex-specific age and growth information for grey triggerfish using the Δ14 C-validated otolith-based age estimation method and the results indicate that the previous characterization of Balistes species as exhibiting moderately rapid growth and as relatively short-lived, based on spine-derived age estimates, are flawed. Otolith-based ages indicated that grey triggerfish and queen triggerfish are moderately slow-growing and long-lived species, attaining maximum ages of 21 and 40 years, respectively. Management efforts for triggerfishes should evaluate these new insights and incorporate the results of otolith-based age estimation into future population monitoring efforts.


Asunto(s)
Tetraodontiformes , Femenino , Masculino , Animales , Peces , Explotaciones Pesqueras , Océano Atlántico
3.
PLoS One ; 17(1): e0262281, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34995331

RESUMEN

Ensuring the accuracy of age estimation in fisheries science through validation is an essential step in managing species for long-term sustainable harvest. The current study used Δ14 C in direct validation of age estimation for queen triggerfish Balistes vetula and conclusively documented that triggerfish sagittal otoliths provide more accurate and precise age estimates relative to dorsal spines. Caribbean fish samples (n = 2045) ranged in size from 67-473 mm fork length (FL); 23 fish from waters of the southeastern U.S. (SEUS) Atlantic coast ranged in size from 355-525 mm FL. Otolith-based age estimates from Caribbean fish range from 0-23 y, dorsal spine-based age estimates ranged from 1-14 y. Otolith-based age estimates for fish from the SEUS ranged from 8-40 y. Growth function estimates from otoliths in the current study (L∞ = 444, K = 0.13, t0 = -1.12) differed from spined-derived estimates in the literature. Our work indicates that previously reported maximum ages for Balistes species based on spine-derived age estimates may underestimate longevity of these species since queen triggerfish otolith-based ageing extended maximum known age for the species by nearly three-fold (14 y from spines versus 40 y from otoliths). Future research seeking to document age and growth population parameters of Balistes species should strongly consider incorporating otolith-based ageing in the research design.


Asunto(s)
Peces/fisiología , Membrana Otolítica/química , Envejecimiento , Animales , Radioisótopos de Carbono/análisis , Explotaciones Pesqueras , Peces/anatomía & histología , Peces/crecimiento & desarrollo , Longevidad , Membrana Otolítica/anatomía & histología , Datación Radiométrica
4.
PLoS One ; 16(5): e0251442, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33979387

RESUMEN

Reef fishes support important fisheries throughout the Caribbean, but a combination of factors in the tropics makes otolith microstructure difficult to interpret for age estimation. Therefore, validation of ageing methods, via application of Δ14C is a major research priority. Utilizing known-age otolith material from north Caribbean fishes, we determined that a distinct regional Δ14C chronology exists, differing from coral-based chronologies compiled for ageing validation from a wide-ranging area of the Atlantic and from an otolith-based chronology from the Gulf of Mexico. Our north Caribbean Δ14C chronology established a decline series with narrow prediction intervals that proved successful in ageing validation of three economically important reef fish species. In examining why our north Caribbean Δ14C chronology differed from some of the coral-based Δ14C data reported from the region, we determined differences among study objectives and research design impact Δ14C temporal relationships. This resulted in establishing the first of three important considerations relevant to applying Δ14C chronologies for ageing validation: 1) evaluation of the applicability of original goal/objectives and study design of potential Δ14C reference studies. Next, we determined differences between our Δ14C chronology and those from Florida and the Gulf of Mexico were explained by differences in regional patterns of oceanic upwelling, resulting in the second consideration for future validation work: 2) evaluation of the applicability of Δ14C reference data to the region/location where fish samples were obtained. Lastly, we emphasize the application of our north Caribbean Δ14C chronology should be limited to ageing validation studies of fishes from this region known to inhabit shallow water coral habitat as juveniles. Thus, we note the final consideration to strengthen findings of future age validation studies: 3) use of Δ14C analysis for age validation should be limited to species whose juvenile habitat is known to reflect the regional Δ14C reference chronology.


Asunto(s)
Ecosistema , Peces , Membrana Otolítica/química , Datación Radiométrica , Animales , Región del Caribe , Arrecifes de Coral
5.
Appl Biochem Biotechnol ; 193(2): 389-404, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33009584

RESUMEN

Proteolytic enzymes are widely distributed in nature, playing essential roles in important biological functions. Recently, the use of plant proteases at the industrial level has mainly increased in the food industry (e.g., cheesemaking, meat tenderizing, and protein hydrolysate production). Current technological and scientific advances in the detection and characterization of proteolytic enzymes have encouraged the search for new natural sources. Thus, this work aimed to explore the milk-clotting and proteolytic properties of different tissues of Vallesia glabra. Aqueous extracts from the leaves, fruits, and seeds of V. glabra presented different protein profiles, proteolytic activity, and milk-clotting activity. The milk-clotting activity increased with temperature (30-65 °C), but this activity was higher in leaf (0.20 MCU/mL) compared with that in fruit and seed extracts (0.12 and 0.11 MCU/mL, respectively) at 50 °C. Proteolytic activity in the extracts assayed at different pH (2.5-12.0) suggested the presence of different types of active proteases, with maximum activity at acidic conditions (4.0-4.5). Inhibitory studies indicated that major activity in V. glabra extracts is related to cysteine proteases; however, the presence of serine, aspartic, and metalloproteases was also evident. The hydrolytic profile of caseins indicated that V. glabra leaves could be used as a rennet substitute in cheesemaking, representing a new and promising source of proteolytic enzymes.


Asunto(s)
Apocynaceae/enzimología , Leche/química , Péptido Hidrolasas/química , Hojas de la Planta/enzimología , Proteínas de Plantas/química , Proteolisis , Semillas/enzimología , Animales , Concentración de Iones de Hidrógeno
6.
J Fish Biol ; 98(4): 1120-1136, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33314115

RESUMEN

Anthropogenic factors that negatively impact reef fishes can include changes in life-history patterns of fisheries-targeted species. Understanding these impacts on growth and population age structure is essential in the management of exploited populations of fishes. This is the first study to directly compare age and growth for a major fisheries species between east and west populations of a transatlantic reef fish. The main goal of this study was to document age and growth in grey triggerfish Balistes capriscus from coastal waters of Ghana in the Gulf of Guinea (GOG) and compare those with the previous growth studies from that region and with the western Atlantic population. A secondary objective of this study was to evaluate the use of otoliths to age triggerfish and to provide a preliminary comparison with spine-derived age estimates. The results obtained from this study provided an updated understanding of the growth and age structure of the eastern B. capriscus population in GOG. The authors documented that shifts in population attributes occurred for B. capriscus after its major decline in abundance. The differences in physical and biotic characteristics of the East and West Atlantic regions and the differences in collection methods of samples make direct comparisons of growth parameters difficult. Nonetheless, overall differences in maximum sizes and ages were apparent; the western Atlantic population had a larger maximum size and older maximum age. The authors also documented that sagittal otoliths can be used to provide age estimates for triggerfish species, and otoliths as an ageing structure had better between-reader precision compared to dorsal spines.


Asunto(s)
Envejecimiento/fisiología , Distribución Animal/fisiología , Arrecifes de Coral , Tetraodontiformes/fisiología , Animales , Océano Atlántico , Tetraodontiformes/crecimiento & desarrollo
7.
Inorg Chem ; 59(11): 7435-7443, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32428400

RESUMEN

A family of neutral bis-cyclometalated Ir(III) complexes based on phenanthridine (phent) derivates as cyclometalating ligands and picolinate as an ancillary ligand are described. The influence of extended conjugation, rigidity, and hydrophobicity as well as the electronic nature of the substituents were investigated in relation to the photoluminescence, PL, and electrochemiluminescence, ECL, properties. A significant increase of ECL in aqueous media is observed upon extension of the aromatic system or by substituting the phenyl with a dibenzofurane moiety, in compounds 2 and 3, respectively. Under real immunoassay conditions, these complexes achieve up to 4-fold higher ECL efficiency than the commercial ruthenium standard. These values, among the highest reported in the literature under these conditions, confirm the potential of iridium complexes as alternative labels in commercial instruments.

8.
Leuk Lymphoma ; 59(10): 2318-2326, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29115891

RESUMEN

Small lymphocytic lymphoma (SLL) is considered as the non-leukemic form of presentation of chronic lymphocytic leukemia (CLL). We have compared the features, genomic alterations, and outcome of 890 patients with CLL and SLL. One hundred and thirteen patients presented as SLL and more frequently had unmutated-IGHV, CD38high, ZAP-70high, CD49dhigh, +12, alterations in genes of NOTCH1, cell cycle, RNA metabolism, and NFkB pathways than CLL. During the follow-up, 46% of SLL patients developed CLL. Time to first treatment (TTFT) was shorter in SLL (10-year: 75% vs 62%; p = .006). Binet stage, SLL, and IGHV were independent predictive factors for TTFT. Transformation to diffuse large B-cell lymphoma was higher (10-year: 12% vs 6%; p = .003), and overall survival was shorter in SLL (10-year: 55% vs 66%; p = .004). When A0 CLL patients were excluded, only CD38 and CD49d expression, +12, and 10-year TTFT remained different between the SLL and CLL patients. In summary, SLL showed only minor clinicobiological differences when compared with CLL in similar clinical stages.


Asunto(s)
Genoma Humano/genética , Leucemia Linfocítica Crónica de Células B/genética , Adulto , Anciano , Anciano de 80 o más Años , Análisis Mutacional de ADN , Femenino , Estudios de Seguimiento , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/mortalidad , Leucemia Linfocítica Crónica de Células B/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Supervivencia , Tiempo de Tratamiento/estadística & datos numéricos , Adulto Joven
9.
Anal Chem ; 88(8): 4174-8, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-26978720

RESUMEN

A family of neutral bis-cyclometalated iridium complexes [Ir(C^N)2(LX)] has been investigated as ECL labels under immunoassay conditions. Among them, the complex based on phenylphenanthridine (pphent) as the C^N ligand, exhibits outstanding performance and it is a candidate to substitute the commercially available Ru-based label in diagnostics.


Asunto(s)
Técnicas Electroquímicas , Iridio/química , Luminiscencia , Compuestos Organometálicos/química , Procesos Fotoquímicos , Agua/química , Inmunoensayo , Soluciones
10.
Drug Metab Pers Ther ; 31(1): 25-34, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26863347

RESUMEN

Pharmacogenetics and pharmacogenomics (PGx) are rapidly growing fields that aim to elucidate the genetic basis for the interindividual differences in drug response. PGx approaches have been applied to many anticancer drugs in an effort to identify relevant inherited or acquired genetic variations that may predict patient response to chemotherapy and targeted therapies. In this article, we discuss the advances in the field of cancer pharmacogenetics and pharmacogenomics, driven by the recent technological advances and new revolutionary massive sequencing technologies and their application to elucidate the genetic bases for interindividual drug response and the development of biomarkers able to personalize drug treatments. Specifically, we present recent progress in breast cancer molecular classifiers, cell-free circulating DNA as a prognostic and predictive biomarker in cancer, patient-derived tumor xenograft models, chronic lymphocytic leukemia genomic landscape, and current pharmacogenetic advances in colorectal cancer. This review is based on the lectures presented by the speakers of the symposium "Pharmacogenetics and Pharmacogenomics as Tools in Cancer Therapy" from the VII Conference of the Spanish Pharmacogenetics and Pharmacogenomics Society (SEFF), held in Madrid (Spain) on April 21, 2015.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Farmacogenética/métodos , Animales , Antineoplásicos/farmacología , Biomarcadores de Tumor/genética , Humanos , Terapia Molecular Dirigida , Neoplasias/genética , Medicina de Precisión/métodos , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
11.
Mol Carcinog ; 55(5): 705-16, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-25808986

RESUMEN

Chromosomal instability resulting in copy number alterations is a hallmark of colorectal cancer (CRC). However, few studies have attempted to characterize the chromosomal changes occurring in early-onset CRC in order to compare them with those taking place within the more extensively studied late-onset CRC subset. Our aim was to characterize the genomic profiles of these two groups of colorectal tumors and to compare them to each other. Array comparative genomic hybridization profiling of 146 colorectal tumors (60 early-onset and 86 late-onset) in combination with an unsupervised analysis was used to define common and specific copy number alterations. We found a number of important differences between the chromosomal instability profiles of each age subset. Thus, losses at 1p36, 1p12, 1q21, 9p13, 14q11, 16p13, and 16p12 were significantly more frequent in younger patients, whereas gains at 7q11 and 7q22 were more frequent in older patients. Moreover, the unsupervised analysis stratified the tumors into two clusters, each one of which was enriched in patients from one of the age subsets. Our findings confirm the existence of substantial differences between the chromosomal instability profiles of the two groups which are more important from a qualitative point of view. Further studies are needed to understand the clinicopathological implications of these dissimilarities.


Asunto(s)
Inestabilidad Cromosómica , Neoplasias Colorrectales/genética , Hibridación Genómica Comparativa/métodos , Variaciones en el Número de Copia de ADN , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/patología , Femenino , Humanos , Masculino , Adulto Joven
12.
Langmuir ; 30(46): 14021-9, 2014 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-25347390

RESUMEN

Light-emitting electrochemical cells (LECs) showing a white emission have been prepared with Langmuir-Blodgett (LB) films of the metallosurfactant bis[2-(2,4-difluorophenyl)pyridine][2-(1-hexadecyl-1H-1,2,3-triazol-4-yl)pyridine]iridium(III) chloride (1), which work with an air-stable Al electrode. They were prepared by depositing a LB film of 1 on top of a layer of poly(N,N'-diphenyl-N,N'-bis(4-hexylphenyl)-[1,1'-biphenyl]-4,4'-diamine (pTPD) spin-coated on indium tin oxide (ITO). The white color of the electroluminescence of the device contrasts with the blue color of the photoluminescence of 1 in solution and within the LB films. Furthermore, the crystal structure of 1 is reported together with the preparation and characterization of the Langmuir monolayers (π-A compression isotherms and Brewster angle microscopy (BAM)) and LB films of 1 (IR, UV-vis and emission spectroscopy, X-ray photoelectron spectroscopy (XPS), specular X-ray reflectivity (SXR), and atomic force microscopy (AFM)).

13.
Genes Chromosomes Cancer ; 52(8): 753-63, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23686965

RESUMEN

The infrequency of translocations in myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemias (CMML) makes their identification and reporting interesting for the recognition of the recurrent ones and the genes involved in these neoplasias. The aims of this study were to identify new translocations associated with MDS and CMML and to establish their frequency in a cohort of 8,016 patients from the Spanish Group of MDS database. The karyotype was evaluable in 5,654 (70%) patients. Among those, 2,014 (36%) had chromosomal abnormalities, including 213 (10%) translocations identified in 195 patients. The translocations were balanced in 183 (86%) cases and unbalanced in 30 (14%) cases. All chromosomes were found to be involved in translocations, with the single exception of the Y chromosome. The chromosomes most frequently involved were in decreasing frequency: 3, 1, 7, 2, 11, 5, 12, 6, and 17. Translocations were found in karyotypes as the unique chromosomal abnormality (33%), associated with another chromosomal abnormality (11%), as a part of a complex karyotype (17%), and as a part of a monosomal karyotype (38%). There were 155 translocations not previously described in MDS or CMML and nine of them appeared to be recurrent.


Asunto(s)
Cromosomas Humanos/genética , Leucemia Mielomonocítica Crónica/genética , Síndromes Mielodisplásicos/genética , Translocación Genética/genética , Cromosomas Humanos/clasificación , Humanos , Cariotipo , Leucemia Mielomonocítica Crónica/patología , Síndromes Mielodisplásicos/patología
14.
Br J Haematol ; 162(1): 74-86, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23614682

RESUMEN

Lenalidomide is an effective drug in low-risk myelodysplastic syndromes (MDS) with isolated del(5q), although not all patients respond. Studies have suggested a role for TP53 mutations and karyotype complexity in disease progression and outcome. In order to assess the impact of complex karyotypes on treatment response and disease progression in 52 lenalidomide-treated patients with del(5q) MDS, conventional G-banding cytogenetics (CC), single nucleotide polymorphism array (SNP-A), and genomic sequencing methods were used. SNP-A analysis (with control sample, lymphocytes CD3+, in 30 cases) revealed 5q losses in all cases. Other recurrent abnormalities were infrequent and were not associated with lenalidomide responsiveness. Low karyotype complexity (by CC) and a high baseline platelet count (>280 × 10(9) /l) were associated with the achievement of haematological response (P = 0·020, P = 0·013 respectively). Unmutated TP53 status showed a tendency for haematological response (P = 0·061). Complete cytogenetic response was not observed in any of the mutated TP53 cases. By multivariate analysis, the most important predictor for lenalidomide treatment failure was a platelet count <280 × 10(9) /l (Odds Ratio = 6·17, P = 0·040). This study reveals the importance of a low baseline platelet count, karyotypic complexity and TP53 mutational status for response to lenalidomide treatment. It supports the molecular study of TP53 in MDS patients treated with lenalidomide.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 5 , Factores Inmunológicos/uso terapéutico , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/genética , Talidomida/análogos & derivados , Anciano , Anciano de 80 o más Años , Bandeo Cromosómico , Progresión de la Enfermedad , Femenino , Humanos , Hibridación Fluorescente in Situ , Lenalidomida , Masculino , Persona de Mediana Edad , Mutación , Síndromes Mielodisplásicos/mortalidad , Polimorfismo de Nucleótido Simple , Talidomida/uso terapéutico , Resultado del Tratamiento
15.
Inorg Chem ; 52(4): 1812-24, 2013 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-23383706

RESUMEN

A series of blue and blue-green emitters based on neutral bis- and tris-cyclometalated Ir(III) complexes with 1-benzyl-4-(2,6-difluorophenyl)-1H-1,2,3-triazole (dfptrBn) as cyclometalating ligand is reported. The bis-cyclometalated complexes of the type [Ir(dfptrBn)(2)(L(^)X)] with different ancillary ligands, L(^)X = picolinate (pic) (2) or 2-(5-(perfluorophenyl)-2H-1,2,4-triazol-3-yl)pyridine (pytrF(5)) (3), are described and their photophysical properties compared with the analogous complexes containing the archetypal 2-(2,4-difluorophenyl)pyridinato (dfppy) as cyclometaled ligand (C(^)N). Complex 2 exhibits a marked solvatochromic behavior, from 475 nm in toluene to 534 nm in formamide, due to the strong MLCT character of its emissive excited state. Complex 3 displays a true-blue emission, narrower in the visible part than FIrpic. In addition, the homoleptic complex [Ir(dfprBn)(3)] (4) and the heteroleptic compounds with mixed arylpyridine/aryltriazole ligands, [Ir(dfptrBn)(2)(C(^)N)] (C(^)N = 2-phenylpyridinato (ppy) (5) or dfppy (6)), have been synthesized and fully characterized. The facial (fac) complex fac-4 is emissive at 77 K showing a deep-blue emission, but it is not luminescent in solution at room temperature similarly to their phenylpyrazole counterparts. However, the fac isomers, fac-5 and fac-6, are highly emissive in solution and thin films, reaching emission quantum yields of 76%, with emission colors in the blue to blue-green region. The photophysical properties for all complexes have been rationalized by means of quantum-chemical calculations. In addition, we constructed electroluminescent devices, organic light-emitting diodes (OLEDs) by sublimation of fac-6, and by solution processed polymer-based devices (PLEDs) using complexes fac-5 or fac-6 as dopants.


Asunto(s)
Técnicas Electroquímicas , Iridio/química , Luminiscencia , Compuestos Organometálicos/química , Compuestos Organometálicos/síntesis química , Triazoles/química , Ligandos , Modelos Moleculares , Estructura Molecular , Teoría Cuántica
16.
Methods Mol Biol ; 973: 121-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23412787

RESUMEN

BAC array-CGH is a powerful method to identify DNA copy number changes (gains, amplifications and deletions) on a genome-wide scale, and to map these changes to genomic sequence. It is based on the analysis of genomic DNA isolated from test and reference cell populations, the differential labelling with fluorescent dyes and the co-hybridization with a genomic array. BAC array-CGH has proven to be a specific, sensitive, and reliable technique, with considerable advantages compared to other methods used for the analysis of DNA copy number changes. The application of genome scanning technologies and the recent advances in bioinformatics tools that enable us to perform a robust and highly sensitive analysis of array-CGH data, useful not only for genome scanning of tumor cells but also in the identification of novel cancer related genes, oncogenes and suppressor genes. Cytogenetic analysis provides essential information for diagnosis and prognosis in patients with hematologic malignancies such as lymphomas. However, the chromosomal interpretation in non-Hodgkin lymphoma (NHL) is sometimes inconclusive. Copy number aberrations identified by BAC array-CGH analyses could be a complementary methodology to chromosomal analysis. In NHL the genomic imbalances might have a prognostic rather than a diagnostic value. In fact, the diagnosis of NHL is based on pathological and molecular cytogenetics data. Furthermore genetic variations and their association with specific types of lymphoma development, and elucidation of the variable genetic pathways leading to lymphoma development, are important directions for future cancer research. Array-CGH, along with FISH and PCR, will be used for routine diagnostic purposes in near future.


Asunto(s)
Hibridación Genómica Comparativa/métodos , Linfoma de Células B Grandes Difuso/genética , Adulto , Anciano , Aberraciones Cromosómicas , Cromosomas Artificiales Bacterianos/genética , ADN/genética , ADN/aislamiento & purificación , Femenino , Dosificación de Gen , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Adulto Joven
17.
Br J Haematol ; 159(3): 311-21, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22958186

RESUMEN

Trisomy 8 is the most common chromosomal gain in myelodysplastic syndromes (MDS), however, little is known about the features of MDS with isolated trisomy 8 and the influence of additional cytogenetic aberrations. We determined the characteristics and prognostic factors of 72 patients with trisomy 8 as a single anomaly and analysed also the impact of other aberrations added to trisomy 8 in another 62 patients. According to our study, MDS with isolated trisomy 8 was more frequent in men, with more than one cytopenia in most patients (62%) and having about 4% bone marrow blasts. The multivariate analysis demonstrated that platelet count and percentage bone marrow blasts had the strongest impact on overall survival (OS). The median OS for isolated trisomy 8, trisomy 8 plus one aberration (tr8 + 1), plus two (tr8 + 2) and plus three or more aberrations (tr8 + ≥3) was 34·3, 40, 23·4 and 5·8 months, respectively (P < 0·001). Trisomy 8 confers a poorer prognosis than a normal karyotype in MDS patients with ≥5% bone marrow blasts. This study supports the view that MDS with isolated trisomy 8 should be included in the intermediate cytogenetic risk group.


Asunto(s)
Aberraciones Cromosómicas , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/mortalidad , Trisomía , Adulto , Anciano , Cromosomas Humanos Par 8 , Progresión de la Enfermedad , Femenino , Humanos , Cariotipo , Masculino , Persona de Mediana Edad , Pronóstico , Riesgo
18.
J Neurooncol ; 110(1): 69-77, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22864683

RESUMEN

Even though much progress has been made towards understanding the molecular nature of glioma, the survival rates of patients affected by this tumour have not changed significantly over recent years. Better knowledge of this malignancy is still needed in order to predict its outcome and improve patient treatment. VAV1 is an GDP/GTP exchange factor for Rho/Rac proteins with oncogenic potential that is involved in the regulation of cytoskeletal dynamics and cell migration. Here we report its overexpression in 59 patients diagnosed with high-grade glioma, and the associated upregulation of a number of genes coding for proteins also involved in cell invasion- and migration-related processes. Unexpectedly, immunohistochemical experiments revealed that VAV1 is not expressed in glioma cells. Instead, VAV1 is found in non-tumoural astrocyte-like cells that are located either peritumouraly or perivascularly. We propose that the expression of VAV1 is linked to synergistic signalling cross-talk between cancer and infiltrating cells. Interestingly, we show that the pattern of expression of VAV1 could have a role in the neoplastic process in glioblastoma tumours.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Proteínas Proto-Oncogénicas c-vav/biosíntesis , Microambiente Tumoral/fisiología , Adulto , Anciano , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Análisis por Conglomerados , Hibridación Genómica Comparativa , Supervivencia sin Enfermedad , Femenino , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Proto-Oncogénicas c-vav/análisis , Receptor Cross-Talk/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
J Integr Bioinform ; 9(3): 206, 2012 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-22829577

RESUMEN

Advances in bioinformatics have contributed towards a significant increase in available information. Information analysis requires the use of distributed computing systems to best engage the process of data analysis. This study proposes a multiagent system that incorporates grid technology to facilitate distributed data analysis by dynamically incorporating the roles associated to each specific case study. The system was applied to genetic sequencing data to extract relevant information about insertions, deletions or polymorphisms.


Asunto(s)
Automatización , Biología Computacional/métodos , Conocimiento , Análisis de Secuencia/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Interfaz Usuario-Computador
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...