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1.
BMC Genomics ; 24(1): 670, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37936076

RESUMEN

BACKGROUND: Broodstock nutritional programming improves the offspring utilization of plant-based diets in gilthead sea bream through changes in hepatic metabolism. Attention was initially focused on fatty acid desaturases, but it can involve a wide range of processes that remain largely unexplored. How all this can be driven by a different genetic background is hardly underlined, and the present study aimed to assess how broodstock nutrition affects differentially the transcriptome and genome-wide DNA methylome of reference and genetically selected fish within the PROGENSA® selection program. RESULTS: After the stimulus phase with a low fish oil diet, two offspring subsets of each genetic background received a control or a FUTURE-based diet. This highlighted a different hepatic transcriptome (RNA-seq) and genome-wide DNA methylation (MBD-seq) pattern depending on the genetic background. The number of differentially expressed transcripts following the challenge phase varied from 323 in reference fish to 2,009 in genetically selected fish. The number of discriminant transcripts, and associated enriched functions, were also markedly higher in selected fish. Moreover, correlation analysis depicted a hyper-methylated and down-regulated gene expression state in selected fish with the FUTURE diet, whereas the opposite pattern appeared in reference fish. After filtering for highly represented functions in selected fish, 115 epigenetic markers were retrieved in this group. Among them, lipid metabolism genes (23) were the most reactive following ordering by fold-change in expression, rendering a final list of 10 top markers with a key role on hepatic lipogenesis and fatty acid metabolism (cd36, pitpna, cidea, fasn, g6pd, lipt1, scd1a, acsbg2, acsl14, acsbg2). CONCLUSIONS: Gene expression profiles and methylation signatures were dependent on genetic background in our experimental model. Such assumption affected the magnitude, but also the type and direction of change. Thus, the resulting epigenetic clock of reference fish might depict an older phenotype with a lower methylation for the epigenetically responsive genes with a negative methylation-expression pattern. Therefore, epigenetic markers will be specific of each genetic lineage, serving the broodstock programming in our selected fish to prevent and mitigate later in life the risk of hepatic steatosis through changes in hepatic lipogenesis and fatty acid metabolism.


Asunto(s)
Dorada , Animales , Dorada/genética , Dorada/metabolismo , Transcriptoma , Epigenoma , Ácido Graso Desaturasas/genética , Ácidos Grasos/metabolismo
2.
Microlife ; 2: uqab011, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34642663

RESUMEN

Epidemics caused by microbial organisms are part of the natural phenomena of increasing biological complexity. The heterogeneity and constant variability of hosts, in terms of age, immunological status, family structure, lifestyle, work activities, social and leisure habits, daily division of time and other demographic characteristics make it extremely difficult to predict the evolution of epidemics. Such prediction is, however, critical for implementing intervention measures in due time and with appropriate intensity. General conclusions should be precluded, given that local parameters dominate the flow of local epidemics. Membrane computing models allows us to reproduce the objects (viruses and hosts) and their interactions (stochastic but also with defined probabilities) with an unprecedented level of detail. Our LOIMOS model helps reproduce the demographics and social aspects of a hypothetical town of 10 320 inhabitants in an average European country where COVID-19 is imported from the outside. The above-mentioned characteristics of hosts and their lifestyle are minutely considered. For the data in the Hospital and the ICU we took advantage of the observations at the Nursery Intensive Care Unit of the Consortium University General Hospital, Valencia, Spain (included as author). The dynamics of the epidemics are reproduced and include the effects on viral transmission of innate and acquired immunity at various ages. The model predicts the consequences of delaying the adoption of non-pharmaceutical interventions (between 15 and 45 days after the first reported cases) and the effect of those interventions on infection and mortality rates (reducing transmission by 20, 50 and 80%) in immunological response groups. The lockdown for the elderly population as a single intervention appears to be effective. This modeling exercise exemplifies the application of membrane computing for designing appropriate multilateral interventions in epidemic situations.

3.
Public Health ; 198: 6-8, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34340013

RESUMEN

OBJECIVES: To describe the characteristics of the workers of activity sectors other than sanitary and socio-sanitary, who go to work with COVID-19 symptoms (GWC19S) during the lockdown or first phase of the lockdown de-escalation in Spain. STUDY DESIGN: An observational cross-sectional study based on a convenience sample selected from the COTS online survey. METHODS: A cross-sectional study based on a sample of n = 9601 workers. Descriptive analyses were performed calculating GWC19S prevalences and fitting robust Poisson regressions to obtain crude and adjusted prevalence ratios. RESULTS: The overall GWC19S prevalence is 5.6%, greater in young people (8.7%), manual workers (8.7%), workers with low salaries (9.5%), and workers of essential sectors (7.4%). Among those workers who went to work regularly to their workplaces, the GWC19S prevalence is 10.0%, greater in young (15.1%), workers with low salaries (14.2%), and women (13.2%). CONCLUSIONS: The axes of inequality of the labor market are clearly represented in the GWC19S phenomenon.


Asunto(s)
COVID-19 , Adolescente , Control de Enfermedades Transmisibles , Estudios Transversales , Femenino , Humanos , SARS-CoV-2 , Factores Socioeconómicos
4.
BMC Genomics ; 19(1): 592, 2018 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-30086708

RESUMEN

BACKGROUND: Anisakis simplex sensu stricto and Anisakis pegreffii are sibling species of nematodes parasitic on marine mammals. Zoonotic human infection with third stage infective larvae causes anisakiasis, a debilitating and potentially fatal disease. These 2 species show evidence of hybridisation in geographical areas where they are sympatric. How the species and their hybrids differ is still poorly understood. RESULTS: Third stage larvae of Anisakis simplex s.s., Anisakis pegreffii and hybrids were sampled from Merluccius merluccius (Teleosti) hosts captured in waters of the FAO 27 geographical area. Specimens of each species and hybrids were distinguished with a diagnostic genetic marker (ITS). RNA was extracted from pools of 10 individuals of each taxon. Transcriptomes were generated using Illumina RNA-Seq, and assembled de novo. A joint assembly (here called merged transcriptome) of all 3 samples was also generated. The inferred transcript sets were functionally annotated and compared globally and also on subsets of secreted proteins and putative allergen families. While intermediary metabolism appeared to be typical for nematodes in the 3 evaluated taxa, their transcriptomes present strong levels of differential expression and enrichment, mainly of transcripts related to metabolic pathways and gene ontologies associated to energy metabolism and other pathways, with significant presence of excreted/secreted proteins, most of them allergens. The allergome of the 2 species and their hybrids has also been thoroughly studied; at least 74 different allergen families were identified in the transcriptomes. CONCLUSIONS: A. simplex s.s., A. pegreffi and their hybrids differ in gene expression patterns in the L3 stage. Strong parent-of-origin effects were observed: A. pegreffi alleles dominate in the expression patterns of hybrids albeit the latter, and A. pegreffii also display significant differences indicating that hybrids are intermediate biological entities among their parental species, and thus of outstanding interest in the study of speciation in nematodes. Analyses of differential expression based on genes coding for secreted proteins suggests that co-infections presents different repertoires of released protein to the host environment. Both species and their hybrids, share more allergen genes than previously thought and are likely to induce overlapping disease responses.


Asunto(s)
Anisakis/genética , Gadiformes/parasitología , Perfilación de la Expresión Génica/métodos , Proteínas del Helminto/genética , Alérgenos/genética , Animales , Anisakis/aislamiento & purificación , Anisakis/patogenicidad , Cruzamiento , Metabolismo Energético , Enfermedades de los Peces/parasitología , Regulación de la Expresión Génica , Larva/genética , Larva/patogenicidad , Anotación de Secuencia Molecular , Análisis de Secuencia de ARN/métodos , Factores de Virulencia/genética
5.
Actas Urol Esp ; 41(7): 471-476, 2017 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27889116

RESUMEN

INTRODUCTION: The iatrogenic loss of the penis is a rare situation. We present a challenging case of deferred total penile reconstruction in a genetic male. MATERIAL AND METHODS: A 57-year-old man with the loss of the penis due to a penile abscess and necrosis secondary to penile curvature surgery. The reconstruction was performed over several operations using a radial forearm free flap (RFFF) and placement of a customised inflatable prosthesis a year later. RESULTS: During the first operation, the penile abscess was drained, the necrotic residues were debrided and placement of hypogastric drainage. Seven weeks later, phalloplasty was performed with RFFF and a tube-in-tube neourethra was constructed. Multiple microsurgical anastomosis was performed, and the donor site was coated with a skin graft from the thigh of partial thickness. The surgery lasted 10hours and had the complication of hair growth in the neourethra, which required mechanical endoscopic depilation on repeated occasions. The patient regained penile sensitivity. Eighteen months after the phalloplasty, a Zephyr single-body inflatable prosthesis (Geneva, Switzerland) was implanted, using the tunica albuginea of the proximal corpus cavernosum. The patient was satisfied with the aesthetics and urinary and sensory function. Four months later, the patient is gaining confidence to consider penetration. CONCLUSIONS: Despite the risk of postoperative complications and the need for multiple operations, phallic reconstruction with RFFF and the placement of a customised prosthetic implant can improve urinary and sexual function secondary to the loss of the penis.


Asunto(s)
Colgajos Tisulares Libres , Prótesis de Pene , Pene/cirugía , Complicaciones Posoperatorias/cirugía , Antebrazo/cirugía , Humanos , Enfermedad Iatrogénica , Masculino , Persona de Mediana Edad , Necrosis , Pene/patología , Procedimientos de Cirugía Plástica/métodos , Procedimientos Quirúrgicos Urológicos/métodos
6.
J R Soc Interface ; 13(114): 20150930, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26763327

RESUMEN

Leptosporangiate ferns have evolved an ingenious cavitation catapult to disperse their spores. The mechanism relies almost entirely on the annulus, a row of 12-25 cells, which successively: (i) stores energy by evaporation of the cells' content, (ii) triggers the catapult by internal cavitation, and (iii) controls the time scales of energy release to ensure efficient spore ejection. The confluence of these three biomechanical functions within the confines of a single structure suggests a level of sophistication that goes beyond most man-made devices where specific structures or parts rarely serve more than one function. Here, we study in detail the three phases of spore ejection in the sporangia of the fern Polypodium aureum. For each of these phases, we have written the governing equations and measured the key parameters. For the opening of the sporangium, we show that the structural design of the annulus is particularly well suited to inducing bending deformations in response to osmotic volume changes. Moreover, the measured parameters for the osmoelastic design lead to a near-optimal speed of spore ejection (approx. 10 m s(-1)). Our analysis of the trigger mechanism by cavitation points to a critical cavitation pressure of approximately -100 ± 14 bar, a value that matches the most negative pressures recorded in the xylem of plants. Finally, using high-speed imaging, we elucidated the physics leading to the sharp separation of time scales (30 versus 5000 µs) in the closing dynamics. Our results highlight the importance of the precise tuning of the parameters without which the function of the leptosporangium as a catapult would be severely compromised.


Asunto(s)
Polypodium/anatomía & histología , Polypodium/fisiología , Esporangios/anatomía & histología , Esporangios/fisiología , Esporas
7.
Occup Med (Lond) ; 65(5): 405-12, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26002717

RESUMEN

BACKGROUND: Work organization in Spain has traditionally been based on a high proportion of passive work. Changes in the labour market in Europe and the economic crisis that began in 2008 may have had an impact on the pace of work in Spain. AIMS: To estimate the prevalence of exposure to high-strain work and passive work in 2010 compared with 2005 and to analyse the distribution by gender, age and occupation of workers exposed to high strain and iso-strain in 2010 compared with 2005. METHODS: Two representative samples of the Spanish working population were compared. Unweighted and weighted prevalences in 2010 were calculated and compared with those in 2005. RESULTS: In the 2010 sample of 5110 workers, 29% (95% CI 27.8; 30.7) were exposed to high strain (of whom 83% had low social support). There was an increase of 6% (95% CI 3.8; 7.1) in high strain, and of 7% (95% CI 5.2; 8.3) to iso-strain, compared with 2005 (n = 7612). In 2010, as in 2005, the proportion of manual workers exposed to strain and iso-strain was more than double the corresponding proportion in non-manual workers. CONCLUSIONS: There has been an intensification of work, reduction in social support and a notable increase in exposure to high strain and iso-strain. The class inequalities reflect the segmentation of the Spanish labour market.


Asunto(s)
Enfermedades Profesionales/epidemiología , Apoyo Social , Estrés Psicológico/epidemiología , Lugar de Trabajo/psicología , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Salud Laboral/normas , Ocupaciones/estadística & datos numéricos , Prevalencia , Factores Sexuales , Factores Socioeconómicos , España/epidemiología , Estrés Psicológico/etiología , Adulto Joven
8.
Science ; 335(6074): 1322, 2012 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-22422975

RESUMEN

Various plants and fungi have evolved ingenious devices to disperse their spores. One such mechanism is the cavitation-triggered catapult of fern sporangia. The spherical sporangia enclosing the spores are equipped with a row of 12 to 13 specialized cells, the annulus. When dehydrating, these cells induce a dramatic change of curvature in the sporangium, which is released abruptly after the cavitation of the annulus cells. The entire ejection process is reminiscent of human-made catapults with one notable exception: The sporangia lack the crossbar that arrests the catapult arm in its returning motion. We show that much of the sophistication and efficiency of the ejection mechanism lies in the two very different time scales associated with the annulus closure.


Asunto(s)
Polypodium/fisiología , Esporangios/fisiología , Esporas/fisiología , Forma de la Célula , Elasticidad , Polypodium/citología , Esporangios/citología , Agua
9.
Nucleic Acids Res ; 36(Database issue): D38-46, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17895280

RESUMEN

In this article, we introduce the Gypsy Database (GyDB) of mobile genetic elements, an in-progress database devoted to the non-redundant analysis and evolutionary-based classification of mobile genetic elements. In this first version, we contemplate eukaryotic Ty3/Gypsy and Retroviridae long terminal repeats (LTR) retroelements. Phylogenetic analyses based on the gag-pro-pol internal region commonly presented by these two groups strongly support a certain number of previously described Ty3/Gypsy lineages originally reported from reverse-transcriptase (RT) analyses. Vertebrate retroviruses (Retroviridae) are also constituted in several monophyletic groups consistent with genera proposed by the ICTV nomenclature, as well as with the current tendency to classify both endogenous and exogenous retroviruses by three major classes (I, II and III). Our inference indicates that all protein domains codified by the gag-pro-pol internal region of these two groups agree in a collective presentation of a particular evolutionary history, which may be used as a main criterion to differentiate their molecular diversity in a comprehensive collection of phylogenies and non-redundant molecular profiles useful in the identification of new Ty3/Gypsy and Retroviridae species. The GyDB project is available at http://gydb.uv.es.


Asunto(s)
Bases de Datos Genéticas , Retroelementos , Retroviridae/genética , Genes Virales , Internet , Filogenia , Proteínas de los Retroviridae/química , Proteínas de los Retroviridae/clasificación , Proteínas de los Retroviridae/genética , Alineación de Secuencia , Secuencias Repetidas Terminales , Interfaz Usuario-Computador
10.
Arch Bronconeumol ; 39(11): 527-30, 2003 Nov.
Artículo en Español | MEDLINE | ID: mdl-14588207

RESUMEN

Inflammatory pseudotumors are rare entities which occasionally affect the pulmonary parenchyma. Their clinical diagnosis arises in a variety of ways and half the time they are detected by chance. Deciding on a therapeutic approach is difficult because a firm diagnosis is established only after studying the excised tissue. We describe our experience with the diagnosis, surgical treatment, and follow up of 4 cases of inflammatory pseudotumor located in the pulmonary parenchyma and treated by surgical resection (by thoracotomy or video assisted thoracoscopic surgery) with good outcomes following complete resection.


Asunto(s)
Granuloma de Células Plasmáticas del Pulmón/patología , Adulto , Humanos , Masculino , Persona de Mediana Edad
11.
J Chromatogr A ; 926(1): 167-74, 2001 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-11554409

RESUMEN

With its detection limit well below 30 pg microl(-1) LC-MS-MS has become a sensitive and thus popular analytical technique for organoarsenical compounds. Collision induced dissociation (CID) is a valuable tool for speciation and facilitates a positive identification of the species detected. However, it is not straightforward to understand the fragmentation pathways of organoarsenical compounds when only CID-MS-MS data is available. In the present paper we have investigated multiple mass spectrometry (MSn, n=1, 2, 3, 4, 5, 6) with electrospray CID fragmentation for a number of organoarsenical compounds likely to occur in the environment. The investigated compounds were tetramethylarsonium, trimethylarsinoxide, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, arsenocholine, and dimethylarsinoylethanol. By CID of (protonated) organoarsenical cations mostly even-electron fragments are produced after neutral loss processes such as elimination of H2, H2O, CH4, C2H2, C2H4, C2H6, HCHO, CH3OH, C2H5OH, C2H4O, and CH2CO. However, abundant odd-electron fragments are also formed after elimination of radical species. Evidence for reduction of As(V) to As(III) as a driving force in the odd-electron ion formation is obtained.


Asunto(s)
Arsenicales/química , Compuestos Organometálicos/química , Espectrometría de Masa por Ionización de Electrospray/métodos
13.
Int Dent J ; 50(1): 57-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10945182

RESUMEN

AIM: Fibronectin is a multifunctional glycoprotein that plays a fundamental role in mechanism of cellular union and in bacterial adhesion in the oral cavity. The aim of this study was to test the clinical relationship between fibronectin concentration in stimulated whole-saliva and the number of Mutans streptococci bacteria. PARTICIPANTS: The sample consisted of 167 children aged 12 years. METHODS: Saliva samples were collected from the subjects. Bacterial quantification was carried out using a semiquantitative method (Dentocult SM, Vivadent). Fibronectin was measured by the ELISA method with modifications. RESULTS: An inverse clinical relation was found between the levels of soluble fibronectin and the number of SM colony forming units. CONCLUSIONS: Bacterial counts sufficiently high to destroy the protein films increase bacterial binding to dental surfaces, thereby contributing to the regulation of bacterial plaque composition and its pathogenic potential. This capacity of glycoproteins to reduce the adhesion of microorganisms to the oral tissues and favour macrophage action supports the hypothesis that such proteins contribute to the first line of immune defence together with secretory antibodies.


Asunto(s)
Caries Dental/inmunología , Fibronectinas/fisiología , Saliva/química , Adhesión Bacteriana , Niño , Recuento de Colonia Microbiana , Caries Dental/microbiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Fibronectinas/análisis , Humanos , Masculino , Estimulación Física , Saliva/microbiología , Streptococcus mutans/aislamiento & purificación , Streptococcus mutans/fisiología
14.
Mol Biol Evol ; 17(7): 1040-9, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10889217

RESUMEN

We performed a comprehensive analysis of the evolution of the Ty3/GYPSY: group of long-terminal-repeat retrotransposons (also known as METAVIRIDAE:). Exhaustive database searches allowed us to detect novel elements of this group. In particular, the Arabidopsis thaliana and Drosophila melanogaster genome sequencing projects have recently disclosed a large number of new Ty3/GYPSY: sequences. So far, elements of three different Ty3/GYPSY: lineages had been described for A. thaliana. Here, we describe six new lineages, which we have called Tit-for-tat1, Tit-for-tat2, Gimli, Gloin, Legolas, and Little Athila. We confirm that plant Ty3/GYPSY: elements form two main monophyletic groups. Moreover, our results suggest that at least four independent ancestral lineages existed before the monocot-dicot split, about 200 MYA. Twelve sequences from D. melanogaster that may correspond to new elements are also described. Some of these sequences are similar to those of OSVALDO: and Ulysses, two elements of the OSVALDO: clade that had never before been described for D. melanogaster. Comparative analyses of multiple organisms, some of them with completely sequenced genomes, show that the number of lineages of Ty3/GYPSY: elements is very variable. Thus, while only 1 lineage is present in Saccharomyces cerevisiae, at least 6 exist in Caenorhabditis elegans, at least 9 are present in the A. thaliana, and perhaps 20 are present in D. melanogaster. Finally, we suggest that the presence of a chromodomain-containing integrase, a feature of some closely related Ty3/GYPSY: elements of fungi, plants, and animals, may be used to define a new METAVIRIDAE: genus.


Asunto(s)
Arabidopsis/genética , Evolución Molecular , Genoma de Planta , Retroelementos , Secuencia de Aminoácidos , Animales , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido
15.
ASDC J Dent Child ; 67(1): 42-6, 9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10736657

RESUMEN

Many attempts have been made to establish the risk profile of dental caries; however, no diagnostic procedures are yet available to reliably predict such risk particularly among the pediatric and adolescent population. Age of subject, a history of caries affecting the primary dentition, the prevalence of Streptococcus mutans, pH values, salivary flow, and the frequency and amount of sugar consumption have been the factors most studied. A cross-sectional study is made of schoolchildren in the 12-13-year age-range to evaluate the relationship between dental caries and CFU/ml of S. mutans and Lactobacillus, salivary buffer capacity, and salivary flow. Likewise, an evaluation is made of the predictive value of the variables, bacterial count and salivary pH with respect to caries. A total of 167 children were subjected to oral examination to establish the DMFT and DMFS indices, followed by the collection of saliva for quantitating S. mutans, Lactobacillus, pH and salivary flow, by the Dentocult (SM)(LB) and Dentobuff systems (Vivadent). The data obtained were subjected to descriptive analysis, comparisons among variables were made by nonparametric testing with a confidence level of 95 percent. Test predictive value was studied in terms of sensitivity, specificity, positive and negative predictive values, and probability ratio. Statistically significant (p < 0.001) correlations were observed between the caries indices and bacterial counts. No significant association was recorded with the rest of the variables studied. Bacterial counts as well as salivary buffer capacities exhibited greater negative than positive predictive values, i.e., they were more effective in identifying healthy individuals than patients who required treatment.


Asunto(s)
Caries Dental/microbiología , Boca/microbiología , Adolescente , Niño , Recuento de Colonia Microbiana , Estudios Transversales , Índice CPO , Pruebas de Actividad de Caries Dental , Femenino , Humanos , Concentración de Iones de Hidrógeno , Lactobacillus/aislamiento & purificación , Masculino , Oportunidad Relativa , Valor Predictivo de las Pruebas , Saliva/química , Saliva/metabolismo , Saliva/microbiología , Tasa de Secreción , Estadísticas no Paramétricas , Streptococcus mutans/aislamiento & purificación
18.
Life Sci ; 31(26): 2947-54, 1982 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-6298535

RESUMEN

New carboxylalkyl compounds derived from Phe-Leu and corresponding to the general formula C6H5-CH2-CH(R)CO-L.Leu with R = -COOH, 3, R = -CH2-COOH, 4, R = -NH-CH2-COOH, 5, R = -NH-(CH2)2-COOH, 6, have been found to inhibit the breakdown of the Gly3-Phe4 bond of [3H] Leu-enkephalin or [3H]D.Ala2-Leu-enkephalin resulting from the action of the mouse striatal metallopeptidases: "enkephalinase" or angiotensin-converting enzyme (A.C.E.). The carboxyl coordinating ability of the Zn atom seems to be significantly higher in ACE than in "enkephalinase". Moreover, IC50 values against "enkephalinase" were found in the same range whatever the length of the chain bearing the carboxyl group whereas a well-defined position of this group with respect to the Zn atom is required for strong ACE inhibition. These features suggest a larger degree of freedom of the carboxyalkyl moieties within the active site of "enkephalinase". Therefore the differential recognition of active sites of both peptidases leads to: i) N-(carboxymethyl)-L-Phe-L-Leu, 5, a competitive inhibitor of "enkephalinase" (KI = 0.7 microM) and ACE (KI = 1.2 microM) which could be used as mixed inhibitor for both enzymes; ii) N-[(R,S)-2-carboxy, 3-benzylpropanoyl]-L-Leucine, 3, a full competitive inhibitor of "enkephalinase" (KI = 0.34 microM) which does not interact with ACE (IC50 greater than 10,000 microM). This compound can be considered as the first example of a new series of highly potent and specific "enkephalinase" inhibitors.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina , Ácidos Carboxílicos/farmacología , Inhibidores de Proteasas , Aminoácidos/farmacología , Animales , Cuerpo Estriado/enzimología , Cinética , Masculino , Ratones , Neprilisina , Relación Estructura-Actividad , Zinc/metabolismo
20.
J Neurochem ; 39(4): 1081-9, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6811698

RESUMEN

The compound [3H]Tyr1,D-Ala2,Leu-OH5]enkephalin has been synthesised as a potentially selective substrate for enkephalin dipeptidyl carboxypeptidase (enkephalinase) activity in brain. Incubations in the presence of homogenates and particulate fractions from rodent and human brain result in the formation of [3H]Tyr-D-Ala-Gly, which can be conveniently isolated by polystyrene bead column chromatography. The enzyme activity responsible for the hydrolysis of the Gly3-Phe4 amide bond of this substrate displays close resemblance to that hydrolysing the natural enkephalins at the same level. In addition, enkephalinase activity characterised in postmortem human brain is closely similar to that in rodent brain, with regard to optimal pH and apparent affinities of various substrates and inhibitors, including the potent compound thiorphan. Enkephalinase activity is distributed in a highly heterogeneous fashion among regions of human brain, the highest levels being found in globus pallidus and pars reticulata of the substantia nigra. This distribution is poorly correlated with that of opiate receptor binding sites but displays some resemblance to that of reported Met5-enkephalin levels.


Asunto(s)
Encéfalo/enzimología , Endopeptidasas/metabolismo , Anciano , Animales , Ácido Edético/farmacología , Leucina Encefalina-2-Alanina , Encefalinas/metabolismo , Femenino , Humanos , Concentración de Iones de Hidrógeno , Cinética , Masculino , Métodos , Ratones , Neprilisina , Especificidad de la Especie , Especificidad por Sustrato , Distribución Tisular , Zinc/farmacología
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