Abstract The objective of this paper is to show an alternative methodology to calculate transmiss... more Abstract The objective of this paper is to show an alternative methodology to calculate transmission-line parameters per unit length. With this methodology, the transmission-line parameters can be obtained starting from impedances measured in one terminal of the ...
Human embryonal cell line RD is derived from rhabdomyosarcoma, a tumor of childhood that arises f... more Human embryonal cell line RD is derived from rhabdomyosarcoma, a tumor of childhood that arises from rhabdomyoblasts probably arrested somewhere along their pathway to maturation. Because actinomycin D is a drug of choice in the treatment of rhabdomyosarcomas, and because it has been used to induce differentiation as an alternative therapy for myeloproliferative syndromes, we treated RD cells with different concentrations of actinomycin D and evaluated the effects on growth and differentiation. Actinomycin D treatment in vitro caused time- and dose-dependent growth inhibition. Interestingly, RD cells treated with low doses (2.85 and 5.7 nmol/L) of actinomycin D for 6 days showed morphologic and phenotypic differentiation, with increased expression of desmin, alpha-actinin, and tropomyosin. However, treatment with 11.4 nmol/L actinomycin D strongly inhibited growth and had cytotoxic effects that prevented the cells from attaining myogenic differentiation. We conclude that exposure of this human embryonal rhabdomyosarcoma cell line to low concentrations of actinomycin D released the neoplastic cells from their blockade, allowing them to recover normal myogenic development. We suggest a potential role for differentiation therapy in the treatment of rhabdomyosarcomas.
ABSTRACT Three hundred thirty-eight isolates of cucumber mosaic cucumovirus (CMV), sampled from n... more ABSTRACT Three hundred thirty-eight isolates of cucumber mosaic cucumovirus (CMV), sampled from natural populations in six areas of Spain between 1989 and 1996, were screened for the presence of satellite RNA (satRNA). The frequency of CMV isolates with satRNA approached 1.00 in Valencia (east Spain) between 1990 and 1994 where a tomato necrosis epidemic induced by CMV+satRNA had started in 1986 and was smaller north and west of this area in 1992 and 1993. After 1994, satRNA almost disappeared from all CMV populations. Genetic typing of satRNA variantswas done by ribonuclease protection assay, and from these data, genetic distances were estimated for any pair of satRNA variants. CMV-satRNA populations were highly diverse, containing 0.07865 nucleotide substitutions per site on average. Data also showed that the whole compared set of 100 satRNA variants form a single population that is not structured according to place, year, host plant, or strain of helper virus (HV). This is in sharp contrast with the metapopulation structure of the Spanish CMV population. Thus, the genetic structure and dynamics of populations of CMV and its satRNA are not coupled. This shows that CMV-satRNA spreads epidemically, as a hyperparasite, in the population of its HV. This conclusion is relevant to the use of CMV-satRNA as a biocontrol agent of CMV.
The action of bradykinin was studied in rat-1 fibroblasts stably expressing K K I -adrenoceptors.... more The action of bradykinin was studied in rat-1 fibroblasts stably expressing K K I -adrenoceptors. It was observed that bradykinin and kallidin markedly increase cytosol calcium concentration, but that the B1 agonist, des-Arg W -bradykinin, only mimicked this effect to a minimal extent. Antagonists, selective for the B2 subtype, such as Hoe 140, blocked this effect of bradykinin and kallidin. Similarly, bradykinin and kallidin stimulated the production of inositol phosphates and B2 antagonists blocked their actions. The possibility that bradykinin could modulate K K I -adrenoceptors was studied. It was observed that bradykinin and kallidin increased K K I -adrenoceptor phosphorylation and that such effect was also blocked by Hoe 140. Interestingly, the ability of norepinephrine to increase intracellular calcium concentration was not altered by pretreatment of the cells with bradykinin, i.e. bradykinin induced K K I -adrenoceptor phosphorylation but this did not lead to receptor desensitization.
This review focuses on α1-adrenoceptor phosphorylation and function. Most of what is currently kn... more This review focuses on α1-adrenoceptor phosphorylation and function. Most of what is currently known is based on studies on the hamster α1B-adrenoceptor. It is known that agonist stimulation leads to homologous desensitization of these receptors and current ...
Two main rights expression languages (RELs) exist to describe licenses governing the access to di... more Two main rights expression languages (RELs) exist to describe licenses governing the access to digital multimedia content: MPEG-21 REL and ODRL (open digital rights language). Both RELs are powerful and complex enough. The use of different RELs could divide the network commerce in two separate factions. We propose a way for interworking between them. They have many similarities that permit to translate expressions from one language into the other one. In the Distributed Multimedia Applications Group (DMAG) we are developing utilities that permit to translate licenses between both RELs. Furthermore, the DMAG has developed a set of applications to generate and check licenses in both RELs. This work first describes the current situation of the RELs. Then the ODRL and MPEG-21 REL are introduced. Later, the interworking between MPEG-21 REL and ODRL is exposed and the DMAG licenses generator and checker are described.
The purpose of this study was to point out processes that can provide triazine oxidation via hydr... more The purpose of this study was to point out processes that can provide triazine oxidation via hydroxyl radical production in a water treatment line. We focus our attention on:- oxido-flocculation, using Fe2+, H2O2 - inter-oxidation, using O3, H2O2 and eventually an heterogeneous catalyst.- disinfection, using UV, O3 and H2O2 combinations.Results show that triazines can be removed by all these processes with different efficiencies. At full scale, the O3/H2O2 process presents the best performances from an economical and technical point of view.
Abstract The objective of this paper is to show an alternative methodology to calculate transmiss... more Abstract The objective of this paper is to show an alternative methodology to calculate transmission-line parameters per unit length. With this methodology, the transmission-line parameters can be obtained starting from impedances measured in one terminal of the ...
Human embryonal cell line RD is derived from rhabdomyosarcoma, a tumor of childhood that arises f... more Human embryonal cell line RD is derived from rhabdomyosarcoma, a tumor of childhood that arises from rhabdomyoblasts probably arrested somewhere along their pathway to maturation. Because actinomycin D is a drug of choice in the treatment of rhabdomyosarcomas, and because it has been used to induce differentiation as an alternative therapy for myeloproliferative syndromes, we treated RD cells with different concentrations of actinomycin D and evaluated the effects on growth and differentiation. Actinomycin D treatment in vitro caused time- and dose-dependent growth inhibition. Interestingly, RD cells treated with low doses (2.85 and 5.7 nmol/L) of actinomycin D for 6 days showed morphologic and phenotypic differentiation, with increased expression of desmin, alpha-actinin, and tropomyosin. However, treatment with 11.4 nmol/L actinomycin D strongly inhibited growth and had cytotoxic effects that prevented the cells from attaining myogenic differentiation. We conclude that exposure of this human embryonal rhabdomyosarcoma cell line to low concentrations of actinomycin D released the neoplastic cells from their blockade, allowing them to recover normal myogenic development. We suggest a potential role for differentiation therapy in the treatment of rhabdomyosarcomas.
ABSTRACT Three hundred thirty-eight isolates of cucumber mosaic cucumovirus (CMV), sampled from n... more ABSTRACT Three hundred thirty-eight isolates of cucumber mosaic cucumovirus (CMV), sampled from natural populations in six areas of Spain between 1989 and 1996, were screened for the presence of satellite RNA (satRNA). The frequency of CMV isolates with satRNA approached 1.00 in Valencia (east Spain) between 1990 and 1994 where a tomato necrosis epidemic induced by CMV+satRNA had started in 1986 and was smaller north and west of this area in 1992 and 1993. After 1994, satRNA almost disappeared from all CMV populations. Genetic typing of satRNA variantswas done by ribonuclease protection assay, and from these data, genetic distances were estimated for any pair of satRNA variants. CMV-satRNA populations were highly diverse, containing 0.07865 nucleotide substitutions per site on average. Data also showed that the whole compared set of 100 satRNA variants form a single population that is not structured according to place, year, host plant, or strain of helper virus (HV). This is in sharp contrast with the metapopulation structure of the Spanish CMV population. Thus, the genetic structure and dynamics of populations of CMV and its satRNA are not coupled. This shows that CMV-satRNA spreads epidemically, as a hyperparasite, in the population of its HV. This conclusion is relevant to the use of CMV-satRNA as a biocontrol agent of CMV.
The action of bradykinin was studied in rat-1 fibroblasts stably expressing K K I -adrenoceptors.... more The action of bradykinin was studied in rat-1 fibroblasts stably expressing K K I -adrenoceptors. It was observed that bradykinin and kallidin markedly increase cytosol calcium concentration, but that the B1 agonist, des-Arg W -bradykinin, only mimicked this effect to a minimal extent. Antagonists, selective for the B2 subtype, such as Hoe 140, blocked this effect of bradykinin and kallidin. Similarly, bradykinin and kallidin stimulated the production of inositol phosphates and B2 antagonists blocked their actions. The possibility that bradykinin could modulate K K I -adrenoceptors was studied. It was observed that bradykinin and kallidin increased K K I -adrenoceptor phosphorylation and that such effect was also blocked by Hoe 140. Interestingly, the ability of norepinephrine to increase intracellular calcium concentration was not altered by pretreatment of the cells with bradykinin, i.e. bradykinin induced K K I -adrenoceptor phosphorylation but this did not lead to receptor desensitization.
This review focuses on α1-adrenoceptor phosphorylation and function. Most of what is currently kn... more This review focuses on α1-adrenoceptor phosphorylation and function. Most of what is currently known is based on studies on the hamster α1B-adrenoceptor. It is known that agonist stimulation leads to homologous desensitization of these receptors and current ...
Two main rights expression languages (RELs) exist to describe licenses governing the access to di... more Two main rights expression languages (RELs) exist to describe licenses governing the access to digital multimedia content: MPEG-21 REL and ODRL (open digital rights language). Both RELs are powerful and complex enough. The use of different RELs could divide the network commerce in two separate factions. We propose a way for interworking between them. They have many similarities that permit to translate expressions from one language into the other one. In the Distributed Multimedia Applications Group (DMAG) we are developing utilities that permit to translate licenses between both RELs. Furthermore, the DMAG has developed a set of applications to generate and check licenses in both RELs. This work first describes the current situation of the RELs. Then the ODRL and MPEG-21 REL are introduced. Later, the interworking between MPEG-21 REL and ODRL is exposed and the DMAG licenses generator and checker are described.
The purpose of this study was to point out processes that can provide triazine oxidation via hydr... more The purpose of this study was to point out processes that can provide triazine oxidation via hydroxyl radical production in a water treatment line. We focus our attention on:- oxido-flocculation, using Fe2+, H2O2 - inter-oxidation, using O3, H2O2 and eventually an heterogeneous catalyst.- disinfection, using UV, O3 and H2O2 combinations.Results show that triazines can be removed by all these processes with different efficiencies. At full scale, the O3/H2O2 process presents the best performances from an economical and technical point of view.
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Papers by jose prado