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1.
Pharm. care Esp ; 19(4): 166-183, 2017. graf, tab
Artículo en Español | IBECS | ID: ibc-166094

RESUMEN

Introducción: La baja adherencia conlleva importantes problemas y es importante medirla para abordar intervenciones farmacéuticas para mejorarla. El test de Morisky-Green es la principal herramienta para ello, pero en nuestro medio hay pocos estudios realizados con él en personas mayores del ámbito comunitario que son quienes acuden a las farmacias. Objetivo: Conocer la adherencia a los tratamientos farmacológicos de las personas mayores que acuden al principal evento orientado al envejecimiento activo en Euskadi, de cara a emprender posibles actuaciones desde la farmacia comunitaria. Material y Métodos: Estudio observacional transversal de adherencia mediante el test de Morisky-Green a todas las personas mayores que acudieron al stand del COFBI durante el Salón Nagusi. Resultados: Se realizaron 498 encuestas. 480 sujetos tomaban algún medicamento (73,1% mujeres, 26,9% hombres). Su edad media era 74,6 años (±5,9) y el 34% vivían solos. De media tomaban 3,2 medicamentos (±2,1). El número medio de tomas diarias era 2,0 (±0,8). 457 sujetos completaron el test, obteniéndose un 49,5% de adherencia. No se hallaron diferencias significativas entre el grupo adherente y el incumplidor en ninguna de las variables independientes. Conclusiones: Las personas mayores que acuden al salón Nagusi muestran un nivel de adherencia al tratamiento farmacológico similar al descrito por la OMS y al detectado en otros estudios en los que se empleó la misma herramienta de medida. Las variables independientes estudiadas, no influyen significativamente en el grado de adherencia, lo que facilitaría el diseño de intervenciones desde la farmacia comunitaria para optimizarla en este tipo de población


Introduction: Low adherence involves significant problems. It is important to measure it in order to set out pharmaceutical interventions to improve it. The Morisky-Green test is the main tool designed for this purpose. Nevertheless, in our environment there are few studies done with this test in elderly people living in the community who are the ones that come to the pharmacies. Objective: To determine the adherence to pharmacological treatments of the elderly people who attend the main event aimed to promote active aging in Euskadi. The objective is to set out possible interventions from the community pharmacy. Material and Methods: Cross-sectional observational study of adherence using the Morisky-Green test in the elderly people who attended the COFBI stand during the Nagusi Hall. Results: 498 surveys were carried out. 480 subjects were taking medication (73.1% women, 26.9% men). Their average age was 74.6 years (± 5.9) and 34% lived alone. On average, they took 3.2 medicines (± 2.1). The mean number of daily intakes was 2.0 (± 0.8). 457 subjects completed the test, obtaining 49.5% of adherence. There were no significant differences between the adherent group and the non-compliant group in any of the independent variables. Conclusions: Elderly people attending Nagusi show a rate of adherence to pharmacological treatment similar to the one described by WHO and to those found in other studies done with the same measurement tool. The independent variables studied did not influence significantly the adherence degree, which would make easier to undertake actions from the community pharmacy to improve adherence in this population


Asunto(s)
Humanos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Cumplimiento de la Medicación/estadística & datos numéricos , Servicios Farmacéuticos/métodos , Enfermedad Crónica/tratamiento farmacológico , Estudios Transversales , Salud del Anciano , Encuestas y Cuestionarios , Evaluación de Eficacia-Efectividad de Intervenciones , Servicios Comunitarios de Farmacia/organización & administración
2.
Sci Rep ; 5: 15958, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26514238

RESUMEN

We present phonon properties of plutonium metal obtained from a combination of density-functional-theory (DFT) electronic structure and the recently developed compressive sensing lattice dynamics (CSLD). The CSLD model is here trained on DFT total energies of several hundreds of quasi-random atomic configurations for best possible accuracy of the phonon properties. The calculated phonon dispersions compare better with experiment than earlier results obtained from dynamical mean-field theory. The density-functional model of the electronic structure consists of disordered magnetic moments with all relativistic effects and explicit orbital-orbital correlations. The magnetic disorder is approximated in two ways: (i) a special quasi-random structure and (ii) the disordered-local-moment method within the coherent potential approximation. Magnetism in plutonium has been debated intensely, but the present magnetic approach for plutonium is validated by the close agreement between the predicted magnetic form factor and that of recent neutron-scattering experiments.

3.
J Phys Condens Matter ; 26(41): 416001, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25237839

RESUMEN

The rare-earth metals have important technological applications due to their magnetic properties, but are scarce and expensive. Development of high-performance magnetic materials with less rare-earth content is desired, but theoretical modeling is hampered by complexities of the rare earths electronic structure. The existence of correlated (atomic-like) 4f electrons in the vicinity of the valence band makes any first-principles theory challenging. Here, we apply and evaluate the efficacy of density-functional theory for the series of lanthanides (rare earths), investigating the influence of the electron exchange and correlation functional, spin-orbit interaction, and orbital polarization. As a reference, the results are compared with those of the so-called 'standard model' of the lanthanides in which electrons are constrained to occupy 4f core states with no hybridization with the valence electrons. Some comparisons are also made with models designed for strong electron correlations. Our results suggest that spin-orbit coupling and orbital polarization are important, particularly for the magnitude of the magnetic moments, and that calculated equilibrium volumes, bulk moduli, and magnetic moments show correct trends overall. However, the precision of the calculated properties is not at the level of that found for simpler metals in the Periodic Table of Elements, and the electronic structures do not accurately reproduce x-ray photoemission spectra.

4.
Neuropharmacology ; 79: 28-36, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24212057

RESUMEN

TASK channels belong to the family of K(+) channels with 4 transmembrane segments and 2 pore domains (4TM/2P) per subunit. These channels have been related to apoptosis in cerebellar granule neurons (CGN), as well as cancer in other tissues. TASK current is regulated by hormones, neurotransmitters, anesthetics and divalent cations, which are not selective. Recently, there has been found some organic compounds that inhibit TASK current selectively. In order to find other modulators, we report here a group of five dihydropyrrolo[2,1-a]isoquinolines (DPIs), four of them with putative anticancer activity, that were evaluated on TASK-1 and TASK-3 channels. The compounds 1, 2 and 3 showed IC50 < 320 µM on TASK-1 and TASK-3, intermediate activity on TASK-1/TASK-3 heterodimer, moderate effect over hslo and TREK-1 (500 µM), and practically not inhibition on Shaker-IR, herg and IRK2.1 potassium channels, when they were expressed heterologously in Xenopus laevis oocytes. In rat CGN, 500 µM of these three compounds induced a decrement by >39% of the TASK-carried leak current. Finally, only compound 1 showed significant protection (∼36%) against apoptotic death of CGN induced by K(+) deprivation. These results suggest that DPI compounds could be potential candidates for designing new selective inhibitors of TASK channels.


Asunto(s)
Isoquinolinas/farmacología , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio de Dominio Poro en Tándem/antagonistas & inhibidores , Pirroles/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Células Cultivadas , Cerebelo/efectos de los fármacos , Cerebelo/fisiología , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Canales de Potasio Éter-A-Go-Go/metabolismo , Isoquinolinas/química , Ratones , Estructura Molecular , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Neuronas/fisiología , Potasio/metabolismo , Bloqueadores de los Canales de Potasio/química , Canales de Potasio de Rectificación Interna/metabolismo , Canales de Potasio de Dominio Poro en Tándem/genética , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Canales de Potasio con Entrada de Voltaje/metabolismo , Pirroles/química , Ratas , Ratas Wistar , Canales de Potasio de la Superfamilia Shaker/metabolismo , Xenopus laevis
5.
Phys Rev Lett ; 103(23): 235501, 2009 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-20366157

RESUMEN

The phase stability of group VB (V, Nb, and Ta) transition metals is explored by first-principles electronic-structure calculations. Alloying with a small amount of a neighboring metal can either stabilize or destabilize the body-centered-cubic phase relative to low-symmetry rhombohedral phases. We show that band-structure effects determine phase stability when a particular group VB metal is alloyed with its nearest neighbors within the same d-transition series. In this case, the neighbor with less (to the left) and more (to the right) d electrons destabilize and stabilize bcc, respectively. When alloying with neighbors of higher d-transition series, electrostatic Madelung energy dominates and stabilizes the body-centered-cubic phase. This surprising prediction invalidates current understanding of simple d-electron bonding that dictates high-symmetry cubic and hexagonal phases.

6.
Parasitology ; 135(9): 1125-31, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18620620

RESUMEN

In previous studies, ultrastructural observations revealed a large number of gap junctions (GJs) in the neck and immature proglottid tissues of Taenia solium tapeworms. In these helminths, cytoplasmic glycogen sacs are connected by numerous discrete GJs to other cells throughout the maturing strobilar tissue. Discontinuous sucrose gradients were used to purify membrane fractions containing GJs, which were identified by ultrastructural analysis. A trans-membrane peptide sequence from a highly conserved innexin region was used to construct a 20-amino acid synthetic peptide and used to raise polyclonal antibodies in rabbits that recognized both a 55 and a 67 kDa protein in a Western blot of the GJ-enriched pellet. Immunohistochemistry of larval and adult worm sections incubated with antiserum to the synthetic peptide and a secondary anti-rabbit IgG bound to fluorescein, revealed strong binding to the tegumentary surface of the worm, as well as patchy fluorescent areas in the parenchyma. The results indicate that both the tegument of cysticerci and adult T. solium contain innexin-rich membranes, which may function as a tegumentary transport system for small molecules.


Asunto(s)
Uniones Comunicantes/fisiología , Proteínas de Insectos/fisiología , Taenia solium/fisiología , Secuencia de Aminoácidos , Animales , Uniones Comunicantes/ultraestructura , Proteínas de Insectos/genética , Larva , Microscopía Electrónica , Taenia solium/genética , Taenia solium/ultraestructura
7.
Curr Top Med Chem ; 8(5): 393-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18393902

RESUMEN

This review focuses in the role that antioxidant enzymes play in protection and other important physiological functions such as signal transduction, cell differentiation, growth and apoptosis. Parasites use these enzymes to evade ROS produced by the host immune response and for development inside the host. In the cestoda Taenia solium, three antioxidant enzymes have been studied: a cystosolic Cu,Zn superoxide dismutase that is a target of cestocidal drugs (bencimidazoles); a 2-Cys peroxiredoxin that is a regulatory enzyme of H(2)O(2), molecule essential for several physiological functions; and two isoforms of glutathione transferases that are immunological targets, since they protect immunized mice against cysticercosis. Moreover, all these enzymes are present in all stages of the parasite. These findings suggest that antioxidant enzymes have an important role in T. solium physiology and infection, therefore they might represent the Achilles' heel of the parasite.


Asunto(s)
Antihelmínticos/farmacología , Antioxidantes/metabolismo , Taenia saginata/efectos de los fármacos , Taenia saginata/enzimología , Vacunas/inmunología , Animales , Taenia saginata/inmunología
8.
J Neural Transm (Vienna) ; 114(12): 1519-28, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17616844

RESUMEN

Effects of blocking N-methyl-D-aspartic acid (NMDA) and non-NMDA glutamatergic receptors on performance in the hole board test was studied in male rats bilaterally cannulated into the nucleus accumbens (Acc). Rats, divided into 5 groups, received either 1 microl injections of saline, (+/-) 2-amino-7-phosphonoheptanoic acid (AP-7) (0.5 or 1 microg) or 2,3-dioxo-6-nitro-1,2,3,4,tetrahydrobenzo-(f)quinoxaline-7-sulphonamide disodium (NBQX, 0.5 or 1 microg) 10 min before testing. An increase by AP-7 was observed in ambulatory movements (0.5 microg; p < 0.05), non-ambulatory movements and number of movements (1 microg; p < 0.05); sniffing and total exploration (1 microg; p < 0.01). When holes were considered in order from the first to the fifth by the number of explorations, the most visited holes (first and second) of the AP-7 group were significantly higher than the corresponding holes of saline group (p < 0.05 for 0.5 microg and p < 0.001 for 1 microg). When the second hole was compared with the first of his group, a difference was only observed in the AP-7 1 microg group (p < 0.001). Increasing differences between the other holes and the first were observed by drug treatment. At molecular level, it was observed that AP-7 induced an increase of the coat protein AP-2 expression in Acc, but not AP-180 neither the synaptic protein synaptophysin. The increase of AP-2 was also observed in the medial prefrontal cortex by the action of AP-7 but not NBQX. We conclude that NMDA glutamatergic blockade might induce an activation of the endocytic machinery into the Acc, leading to stereotypies and perseverations, lacking cortical intentional direction.


Asunto(s)
Endocitosis/fisiología , Antagonistas de Aminoácidos Excitadores/farmacología , Núcleo Accumbens/metabolismo , Corteza Prefrontal/metabolismo , 2-Amino-5-fosfonovalerato/análogos & derivados , 2-Amino-5-fosfonovalerato/farmacología , Complejo 2 de Proteína Adaptadora/efectos de los fármacos , Complejo 2 de Proteína Adaptadora/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Endocitosis/efectos de los fármacos , Glutamina/metabolismo , Immunoblotting , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Núcleo Accumbens/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Quinoxalinas/farmacología , Ratas , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores
9.
Mol Ecol ; 15(10): 2809-19, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16911202

RESUMEN

The arctic fox (Alopex lagopus) in Scandinavia is classified as critically endangered after having gone through a severe decline in population size in the beginning of the 20th century, from which it has failed to recover despite more than 65 years of protection. Arctic foxes have a high dispersal rate and often disperse over long distances, suggesting that there was probably little population differentiation within Scandinavia prior to the bottleneck. It is, however, possible that the recent decline in population size has led to a decrease in dispersal and an increase in population fragmentation. To examine this, we used 10 microsatellite loci to analyse genetic variation in 150 arctic foxes from Scandinavia and Russia. The results showed that the arctic fox in Scandinavia presently is subdivided into four populations, and that the Kola Peninsula and northwest Russia together form a large fifth population. Current dispersal between the populations seemed to be very low, but genetic variation within them was relatively high. This and the relative F(ST) values among the populations are consistent with a model of recent fragmentation within Scandinavia. Since the amount of genetic variation is high within the populations, but the populations are small and isolated, demographic stochasticity seems to pose a higher threat to the populations' persistence than inbreeding depression and low genetic variation.


Asunto(s)
Biodiversidad , Zorros/genética , Zorros/fisiología , Alelos , Animales , Flujo Génico/genética , Variación Genética , Geografía , Repeticiones de Microsatélite/genética , Dinámica Poblacional , Especificidad de la Especie
10.
Braz. j. med. biol. res ; 39(3): 365-370, Mar. 2006. graf
Artículo en Inglés | LILACS | ID: lil-421364

RESUMEN

We have observed that intracerebroventricular (icv) injection of selective N-methyl-D-aspartic acid (NMDA)-type glutamatergic receptor antagonists inhibits lordosis in ovariectomized (OVX), estrogen-primed rats receiving progesterone or luteinizing hormone-releasing hormone (LHRH). When NMDA was injected into OVX estrogen-primed rats, it induced a significant increase in lordosis. The interaction between LHRH and glutamate was previously explored by us and another groups. The noradrenergic systems have a functional role in the regulation of LHRH release. The purpose of the present study was to explore the interaction between glutamatergic and noradrenergic transmission. The action of prazosin, an alpha1- and alpha2b-noradrenergic antagonist, was studied here by injecting it icv (1.75 and 3.5 µg/6 µL) prior to NMDA administration (1 µg/2 µL) in OVX estrogen-primed Sprague-Dawley rats (240-270 g). Rats manually restrained were injected over a period of 2 min, and tested 1.5 h later. The enhancing effect induced by NMDA on the lordosis/mount ratio at high doses (67.06 ± 3.28, N = 28) when compared to saline controls (6 and 2 µL, 16.59 ± 3.20, N = 27) was abolished by prazosin administration (17.04 ± 5.52, N = 17, and 9.33 ± 3.21, N = 20, P < 0.001 for both doses). Plasma LH levels decreased significantly only with the higher dose of prazosin (1.99 ± 0.24 ng/mL, N = 18, compared to saline-NMDA effect, 5.96 ± 2.01 ng/mL, N = 13, P < 0.05). Behavioral effects seem to be more sensitive to the alpha-blockade than hormonal effects. These findings strongly suggest that the facilitatory effects of NMDA on both lordosis and LH secretion in this model are mediated by alpha-noradrenergic transmission.


Asunto(s)
Animales , Femenino , Ratas , Antagonistas Adrenérgicos alfa/farmacología , Hormona Luteinizante/sangre , Prazosina/farmacología , Conducta Sexual Animal/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Inyecciones Intraventriculares , Hormona Luteinizante/efectos de los fármacos , N-Metilaspartato/antagonistas & inhibidores , Norepinefrina , Ovariectomía , Postura/fisiología , Ratas Sprague-Dawley , Conducta Sexual Animal/fisiología
11.
Braz J Med Biol Res ; 39(3): 365-70, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16501816

RESUMEN

We have observed that intracerebroventricular (icv) injection of selective N-methyl-D-aspartic acid (NMDA)-type glutamatergic receptor antagonists inhibits lordosis in ovariectomized (OVX), estrogen-primed rats receiving progesterone or luteinizing hormone-releasing hormone (LHRH). When NMDA was injected into OVX estrogen-primed rats, it induced a significant increase in lordosis. The interaction between LHRH and glutamate was previously explored by us and another groups. The noradrenergic systems have a functional role in the regulation of LHRH release. The purpose of the present study was to explore the interaction between glutamatergic and noradrenergic transmission. The action of prazosin, an alpha1- and alpha2b-noradrenergic antagonist, was studied here by injecting it icv (1.75 and 3.5 microg/6 microL) prior to NMDA administration (1 microg/2 microL) in OVX estrogen-primed Sprague-Dawley rats (240-270 g). Rats manually restrained were injected over a period of 2 min, and tested 1.5 h later. The enhancing effect induced by NMDA on the lordosis/mount ratio at high doses (67.06 +/- 3.28, N = 28) when compared to saline controls (6 and 2 microL, 16.59 +/- 3.20, N = 27) was abolished by prazosin administration (17.04 +/- 5.52, N = 17, and 9.33 +/- 3.21, N = 20, P < 0.001 for both doses). Plasma LH levels decreased significantly only with the higher dose of prazosin (1.99 +/- 0.24 ng/mL, N = 18, compared to saline-NMDA effect, 5.96 +/- 2.01 ng/mL, N = 13, P < 0.05). Behavioral effects seem to be more sensitive to the alpha-blockade than hormonal effects. These findings strongly suggest that the facilitatory effects of NMDA on both lordosis and LH secretion in this model are mediated by alpha-noradrenergic transmission.


Asunto(s)
Antagonistas Adrenérgicos alfa/farmacología , Hormona Luteinizante/sangre , Prazosina/farmacología , Conducta Sexual Animal/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Animales , Femenino , Inyecciones Intraventriculares , Hormona Luteinizante/efectos de los fármacos , N-Metilaspartato/antagonistas & inhibidores , Norepinefrina/metabolismo , Ovariectomía , Postura/fisiología , Ratas , Ratas Sprague-Dawley , Conducta Sexual Animal/fisiología
12.
Parasitol Res ; 93(2): 137-44, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15127293

RESUMEN

Glutathione S-transferases are major phase II detoxification enzymes. Taenia solium, a parasite of humans and pigs, is exposed to toxic products. The aim of this work was to purify and characterize a T. solium glutathione S-transferase isoform of 26.5 kDa (SGST26.5) in order to obtain its kinetic parameters. Homogeneous SGST26.5 was obtained by a simple purification procedure. SGST26.5 showed a p I of 7.07, and a native Mr of 60 kDa with 26.5 kDa subunits. The optimum activity for SGST26.5 was found at pH 6.5-7.0 in the range 10-42 degrees C. SGST26.5 had a specific enzyme activity of 78, 7.1, 6.6, and 0.7 microM min(-1) mg(-1) with CDNB, 1,2-dichloro-4-nitrobenzene, 2,4-hexadienal and trans-2-nonenal as substrates, respectively. It also had a kcat/ K(mCDNB)=2.15 x 10(3) M(-1 )s(-1), kcat/ KmGSH)=4.5 x 10(3) M(-1 )s(-1) and Vmax for GSH and CDNB=74 and 77 microM min(-1) mg(-1), respectively. SGST26.5 was inhibited in a noncompetitive form by cibacron blue, bromosulfophthalein and triphenyltin chloride. Inhibition studies as a function of inhibitor concentration show that the enzyme is a homodimer. Bireactant system analysis show that it follows an ordered sequential mechanism.


Asunto(s)
Glutatión Transferasa , Isoenzimas , Taenia/enzimología , Animales , Glutatión Transferasa/química , Glutatión Transferasa/aislamiento & purificación , Glutatión Transferasa/metabolismo , Concentración de Iones de Hidrógeno , Isoenzimas/química , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Cinética , Taenia/crecimiento & desarrollo , Temperatura
13.
Neuroscience ; 120(3): 855-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12895525

RESUMEN

Sleep is an unavoidable activity of the brain. The delay of the time to sleep (sleep deprivation), induces an increase of slow-wave sleep and rapid-eye-movement (REM) sleep (rebound) once the subject is allowed to sleep. This drive to sleep has been hypothesized to be dependent on the accumulation of sleep-inducing molecules and on the high expression of these molecule receptors. In this study we selectively deprived rats of REM sleep for 24 h by using the flowerpot technique. One group deprived of REM sleep was treated with SR141716A, a cannabinoid receptor 1 (CB1) receptor antagonist and then allowed to sleep for the next 4 h. Two other groups were killed, one immediately after the REM sleep deprivation period and the other after 2 h of REM sleep rebound (REM sleep deprivation plus 2 h of rebound). In both groups we determined the expression of the CB1 receptor and its mRNA. Results indicated that SR141716A prevents REM sleep rebound and REM sleep deprivation does not modify the expression of the CB1 protein or mRNA. However, REM sleep deprivation plus 2 h of sleep rebound increased the CB1 receptor protein and, slightly but significantly, decreased mRNA expression. These results suggest that endocannabinoids may be participating in the expression of REM sleep rebound.


Asunto(s)
Receptor Cannabinoide CB1/metabolismo , Privación de Sueño , Sueño REM , Animales , Cannabinoides/antagonistas & inhibidores , Masculino , Piperidinas/farmacología , Pirazoles/farmacología , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptor Cannabinoide CB1/antagonistas & inhibidores , Rimonabant , Sueño , Fases del Sueño
14.
Proc Natl Acad Sci U S A ; 100(10): 6133-8, 2003 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-12730372

RESUMEN

The biosynthesis of most secondary metabolites in different bacteria is strongly depressed by inorganic phosphate. The two-component phoR-phoP system of Streptomyces lividans has been cloned and characterized. PhoR showed all of the characteristics of the membrane-bound sensor proteins, whereas PhoP is a member of the DNA-binding OmpR family. Deletion mutants lacking phoP or phoR-phoP, were unable to grow in minimal medium at low phosphate concentration (10 microM). Growth was fully restored by complementation with the phoR-phoP genes. Both S. lividans DeltaphoP and DeltaphoR-phoP deletion mutants were unable to synthesize extracellular alkaline phosphatase (AP) as shown by immunodetection with anti-AP antibodies and by enzymatic analysis, suggesting that the PhoR-PhoP system is required for expression of the AP gene (phoA). Synthesis of AP was restored by complementation of the deletion mutants with phoR-phoP. The biosynthesis of two secondary metabolites, actinorhodin and undecylprodigiosin, was significantly increased in both solid and liquid medium in the DeltaphoP or DeltaphoR-phoP deletion mutants. Negative phosphate control of both secondary metabolites was restored by complementation with the phoR-phoP cluster. These results prove that expression of both phoA and genes implicated in the biosynthesis of secondary metabolites in S. lividans is regulated by a mechanism involving the two-component PhoR-PhoP system.


Asunto(s)
Proteínas Bacterianas/genética , Streptomyces/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/metabolismo , Genes Bacterianos , Cinética , Datos de Secuencia Molecular , Fosfatos/metabolismo , Plásmidos , Mapeo Restrictivo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Streptomyces/genética , Streptomyces/crecimiento & desarrollo
15.
Neuroscience ; 117(1): 197-201, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12605905

RESUMEN

Endocannabinoids seem to play a role in the modulation of alertness. Therefore, we measured cannabinoid receptor 1 (CB1R) protein by Western blot and messenger RNA (mRNA) by reverse transcription-polymerase chain reaction in the pons of rats across the 24-h period. We performed evaluations every 4 h beginning at 09:00 h. Rats were under a controlled light/dark cycle 12:12 (lights on at 08:00 h). Our data suggest that the expression of CB1R gene depends on diurnal variations, with maximum expression at 13:00 h for protein and 21:00 h for mRNA, and minimum expression at 01:00 and 09:00 h, respectively. We also analyzed CB1R protein and mRNA levels in the pons of rats deprived of total sleep for 24 h and in rats with a 24-h period of sleep deprivation plus a 2-h period of sleep rebound. Unlike sleep deprivation, sleep rebound significantly increased CB1R protein while decreasing mRNA. Despite the fact that we used gentle manipulation to deprive the animals of sleep, there may be a potential influence of stress on this effect, too. However, these facts suggest that CB1R gene expression is modulated by the light/dark cycle and by sleep.


Asunto(s)
Ácidos Grasos Insaturados/biosíntesis , Puente/metabolismo , Receptores de Droga/biosíntesis , Privación de Sueño/metabolismo , Animales , Moduladores de Receptores de Cannabinoides , Ritmo Circadiano/fisiología , Regulación de la Expresión Génica/fisiología , Masculino , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Receptores de Cannabinoides , Sueño/fisiología
16.
Int J Cosmet Sci ; 25(3): 127-35, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18494894

RESUMEN

Axillary malodour is caused by the biotransformation of non-odorous precursors present in apocrine sweat and sebum by the axillary microflora. To counter this, underarm products typically contain high levels of bactericides. However, after an initial decrease in bacterial numbers, the surviving cells grow, producing a concomitant rise in axillary odour. A sustained deodorant effect might be achieved without recourse to bactericidal action if this bacterial growth could be inhibited for extended periods. The current study attempted to inhibit axillary bacterial growth by nutrient deprivation, primarily that of iron (Fe(III)). In vitro analyses identified iron (Fe(III)) as the trace metal whose deprivation had the most profound effect on bacterial growth. Further in vitro investigations with Fe-chelating agents demonstrated that a number of compounds with high binding constants for Fe(III) showed optimal activity. One candidate molecule, diethylenetriaminepentaacetic acid (DTPA), was capable of effectively inhibiting bacterial growth in vitro and on the skin of the lower back. Some bacterial species could additionally utilize iron bound to the iron carrier protein transferrin present in eccrine sweat. This was minimized by the use of an agent, butylated hydroxytoluene (BHT), capable of liberating iron from transferrin via reduction of transferrin-bound ferric ions, allowing subsequent sequestration of Fe(II). Deodorant efficacy evaluation of the combination of DTPA and BHT showed deodorancy benefits over and above that afforded by DTPA alone. This mixture of DTPA and BHT supplemented to a standard ethanolic deodorant, used on 50 people for 2 weeks, was highly effective in limiting bacterial growth in the axilla. Total aerobic bacteria in the axillae were reduced from a mean of log 5.75 (+/-0.73) to log 4.50 (+/-0.90) colony-forming units (cfu) cm(-2) (n = 27, P < 0.01) compared with a non-fortified standard ethanolic deodorant. This was reflected in significant decreases in axillary malodour production, as determined by malodour assessments (P < 0.01). The profile of the axillary microflora was maintained, and all populations were rapidly returned to preuse levels after cessation of product use. This new deodorant technology was benchmarked against leading antimicrobial-based deodorant systems. In three separate deodorant efficacy evaluations, the combination of DTPA and BHT was tested against Triethyl citrate, Triclosan and Farnesol in standard unfragranced ethanolic formulations. The combination of DTPA and BHT showed highly significant deodorancy benefits over and above all these antimicrobial-based deodorant technologies. The combination of an efficient iron chelator with an agent capable of liberating iron from transferrin offers significant benefits in terms of bacterial growth inhibition on the skin and provides a new route to axillary deodorancy.

17.
Vet Microbiol ; 90(1-4): 329-39, 2002 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-12414153

RESUMEN

The Brucella BvrR/BvrS two-component regulatory system is highly similar to the regulatory and sensory proteins of Sinorhizobium and Agrobacterium necessary for endosymbiosis and pathogenicity in plants, and very similar to a putative system present in the animal pathogen Bartonella. Mutations in the bvrR or bvrS genes hamper the penetration of B. abortus in non-phagocytic cells and impairs intracellular trafficking and virulence. In contrast to virulent Brucella, BvrR/BvrS mutants do not recruit small GTPases of the Rho subfamily required for actin polymerization and penetration to cells. Dysfunction of the BvrR/BvrS system alters the outer membrane permeability, the expression of several group 3 outer membrane proteins and the pattern of lipid A acylation. Constructs of virulent B. abortus chimeras containing heterologous LPS from the bvrS(-) mutant demonstrated an altered permeability to cationic peptides similar to that of the BvrR/BvrS mutants. We hypothesize that the Brucella BvrR/BvrS is a system devoted to the homeostasis of the outer membrane and, therefore in the interface for cell invasion and mounting the required structures for intracellular parasitism.


Asunto(s)
Proteínas Bacterianas/genética , Brucella/genética , Brucella/patogenicidad , Secuencia de Aminoácidos , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/genética , Vacunas Bacterianas , Brucella/inmunología , GTP Fosfohidrolasas/genética , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Datos de Secuencia Molecular , Mutagénesis , Conformación Proteica , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Virulencia
18.
Proc Natl Acad Sci U S A ; 99(19): 12375-80, 2002 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-12218183

RESUMEN

The Brucella BvrR/BvrS two-component regulatory system is homologous to the ChvI/ChvG systems of Sinorhizobium meliloti and Agrobacterium tumefaciens necessary for endosymbiosis and pathogenicity in plants. BvrR/BvrS controls cell invasion and intracellular survival. Probing the surface of bvrR and bvrS transposon mutants with monoclonal antibodies showed all described major outer membrane proteins (Omps) but Omp25, a protein known to be involved in Brucella virulence. Absence of Omp25 expression was confirmed by two-dimensional electrophoresis of envelope fractions and by gene reporter studies. The electrophoretic analysis also revealed reduction or absence in the mutants of a second set of protein spots that by matrix-assisted laser desorption ionization MS and peptide mass mapping were identified as a non-previously described Omp (Omp3b). Because bvrR and bvrS mutants are also altered in cell-surface hydrophobicity, permeability, and sensitivity to surface-targeted bactericidal peptides, it is proposed that BvrR/BvrS controls cell envelope changes necessary to transit between extracellular and intracellular environments. A genomic search revealed that Omp25 (Omp3a) and Omp3b belong to a family of Omps of plant and animal cell-associated alpha-Proteobacteria, which includes Rhizobium leguminosarum RopB and A. tumefaciens AopB. Previous work has shown that RopB is not expressed in bacteroids, that AopB is involved in tumorigenesis, and that dysfunction of A. tumefaciens ChvI/ChvG alters surface properties. It is thus proposed that the BvrR/BvrS and Omp3 homologues of the cell-associated alpha-Proteobacteria play a role in bacterial surface control and host cell interactions.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , Brucella abortus/genética , Brucella abortus/patogenicidad , Genes Bacterianos , Rhizobiaceae/genética , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Secuencia de Bases , ADN Bacteriano/genética , Regulación Bacteriana de la Expresión Génica , Operón Lac , Datos de Secuencia Molecular , Mutación , Filogenia , Especificidad de la Especie , Virulencia/genética
19.
J Dent Res ; 81(8): 541-6, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12147744

RESUMEN

Little is known about the molecular mechanisms that regulate the cementogenesis process, because specific cementum markers are not yet available. To investigate whether a cementoblastoma-conditioned medium-derived protein (CP) could be useful as a cementum biological marker, we studied its expression and distribution in human periodontal tissues, human periodontal ligament, alveolar bone, and cementoblastoma-derived cells. In human periodontal tissues, immunoreactivity to anti-CP was observed throughout the cementoid phase of acellular and cellular cementum, cementoblasts, cementocytes, cells located in the endosteal spaces of human alveolar bone, and in cells in the periodontal ligament located near the blood vessels. Immunopurified CP promoted cell attachment on human periodontal ligament, alveolar bone-derived cells, and gingival fibroblasts. A monoclonal antibody against bovine cementum attachment protein (CAP) cross-reacted with CP. These findings indicate that CP identifies potential cementoblast progenitor cells, is immunologically related to CAP species, and serves as a biological marker for cementum.


Asunto(s)
Moléculas de Adhesión Celular/análisis , Cemento Dental/metabolismo , Tumores Odontogénicos/metabolismo , Adulto , Proceso Alveolar/citología , Proceso Alveolar/metabolismo , Análisis de Varianza , Animales , Anticuerpos , Biomarcadores/análisis , Bovinos , Adhesión Celular , Técnicas de Cultivo de Célula , Medios de Cultivo Condicionados , Cemento Dental/citología , Fibroblastos/citología , Encía/citología , Encía/metabolismo , Humanos , Immunoblotting , Inmunohistoquímica , Masculino , Tumores Odontogénicos/patología , Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , Estadística como Asunto , Células Madre/citología , Células Madre/metabolismo , Células Tumorales Cultivadas
20.
Parasitol Res ; 88(5): 398-404, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12049455

RESUMEN

A Taenia solium larval glutathione S-transferase fraction (SGSTF), composed of two proteins with Mr 25,500 (SGSTM1) and 26,500 (SGSTM2), was purified by GSH-sepharose. Its N-terminal sequence analysis revealed that both proteins are related to mammalian mu-class GST enzymes. A cDNA clone coding for SGSTM1 was isolated and the amino acid sequence analysis showed close identity with two Echinococcus GSTs and also high identity with several mu-class GSTs that have been reported. In addition, SGSTM1 presents a similar structure to mu-class GSTs, including the mu loop. The recombinant SGSTM1 is a dimeric protein with enzymatic properties clearly related to mammalian mu-class GSTs. Western blot studies indicated that SGSTM1 is not antigenically related to SGSTM2 or mammalian GSTs from rabbit, pig and rat livers. Immunization with SGSTF and SGSTM2 was highly effective in reducing cysticerci load in murine cysticercosis. In contrast, no protection was obtained using native SGSTM1 and recombinant SGSTM1 as immunogens.


Asunto(s)
Glutatión Transferasa , Taenia solium/enzimología , Secuencia de Aminoácidos , Animales , Clonación Molecular , Cisticercosis/prevención & control , ADN de Helmintos/análisis , ADN de Helmintos/genética , Femenino , Glutatión Transferasa/química , Glutatión Transferasa/genética , Glutatión Transferasa/inmunología , Glutatión Transferasa/metabolismo , Inmunización , Isoenzimas , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Especificidad por Sustrato , Taenia solium/genética , Taenia solium/crecimiento & desarrollo , Taenia solium/inmunología , Vacunas/administración & dosificación
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