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1.
Sci Total Environ ; 751: 141858, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32892081

RESUMEN

Over the last 10 years applied scientific research has been carried out in Romania to tacked the residential radon issues. The increased interest to reduce the carbon footprint of buildings has lead to the implementation and use of new architectural solutions aimed to save energy in houses and other buildings. As a consequence, the degree of retrofit in existing buildings and energy efficiency of new buildings promoted the need to not only mitigate indoor radon, but improve indoor air quality overall. The present study found that the while the best performance in radon reduction was confirmed to be based on sub-slab depressurization (61% - 95% reduction), centralized and decentralized mechanical supply and exhaust ventilation with heat recovery yielded a good efficiency in overall improvement of indoor air quality (CO2, VOC, RH, temperature). The outcome of our research, as well as future perspectives, take into account the recommended harmonization of energy efficiency programs with those of public health by finding and applying the best technologies in compliance with energy saving and indoor environmental quality.

2.
Ann Burns Fire Disasters ; 33(3): 253-261, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33304217

RESUMEN

Disaster myths pose a great challenge in disaster risk management all over the world. These misconceptions mean barriers to disaster higher education as well. This research is designed to examine these beliefs among disaster management students at the National University of Public Service, Hungary, as well as in a control group compiled from students from three other Hungarian universities. Based on the methodology of research published by David Alexander, a questionnaire was edited with 19 false statements about disaster events. Respondents had to evaluate them on a Likert scale from 1 to 5, where 1 means "completely disagree" and 5 means "completely agree". Strong agreement was expressed for some of the misconceptions regarding disasters (e.g. unburied bodies constitute a serious health hazard), and to a lesser degree for others (e.g. disasters cannot be managed systematically). The results of the control group reached similar values to those of the test groups, however in some cases the former tend to be more skeptical about the statements. Although Hungarian students shared the same beliefs as US and Italian students, the Hungarians seem to be less critical of the statements. These disaster myths create a serious problem in disaster higher education and have a great impact on future disaster managers in the field.


Les mythes concernant les catastrophes obèrent leur prise en charge, ce à travers le monde et interfèrent avec la formation en médecine de catastrophe (MC). Ce travail a pour but d'évaluer les croyances de 165 étudiants en MC de l'Université Nationale de Service Public (UNSP) et de les comparer à 100 témoins (T) recrutés dans d'autres universités hongroises. Un questionnaire élaboré à partir de la méthode publiée par David Alexander, comprenant 19 assertions fausses concernant les catastrophes a été distribué. Les réponses, selon l'échelle de Likert, étaient cotées de 1 (je suis fermement en désaccord) à 5 (j'agrée complétement). Certaines croyances, comme le risque sanitaire élevé lié aux corps non enterrés, étaient largement partagées, d'autres, comme l'impossibilité d'une prise en charge standardisée, l'étant plus modestement. Les réponses étaient comparables dans les 2 groupes, les étudiants de l'UNSP étant toutefois plus sceptiques dans certains cas. Les étudiants hongrois, bien que partageant les mêmes croyances que les italiens et les américains semblent toutefois moins critiques à leurs égards. Ces fausses réalités posent le problème de la formation MC en Hongrie et de la prise en charge sub-optimale d'une catastrophe.

3.
Nat Commun ; 11(1): 5601, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-33154374

RESUMEN

The extent to which species can balance out the loss of suitable habitats due to climate warming by shifting their ranges is an area of controversy. Here, we assess whether highly efficient wind-dispersed organisms like bryophytes can keep-up with projected shifts in their areas of suitable climate. Using a hybrid statistical-mechanistic approach accounting for spatial and temporal variations in both climatic and wind conditions, we simulate future migrations across Europe for 40 bryophyte species until 2050. The median ratios between predicted range loss vs expansion by 2050 across species and climate change scenarios range from 1.6 to 3.3 when only shifts in climatic suitability were considered, but increase to 34.7-96.8 when species dispersal abilities are added to our models. This highlights the importance of accounting for dispersal restrictions when projecting future distribution ranges and suggests that even highly dispersive organisms like bryophytes are not equipped to fully track the rates of ongoing climate change in the course of the next decades.


Asunto(s)
Briófitas/fisiología , Cambio Climático , Dispersión de las Plantas/fisiología , Briófitas/clasificación , Briófitas/crecimiento & desarrollo , Ecosistema , Europa (Continente) , Extinción Biológica , Predicción , Modelos Teóricos , Viento
4.
Sci Total Environ ; 669: 887-892, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30897444

RESUMEN

In the framework of the last Council Directive 2013/59 (Euratom, 2014) laying down basic safety standards for protection against the dangers arising from exposure to ionizing radiation, the problem of radon was assumed in Romania at national level by responsible authorities through the design and development of a National Radon Action Plan and an adequate legislation (HG nr. 526/2018). In order to identify radon risk areas, however, it is necessary to perform systematic radon measurements in different environmental media (soil gas, water, indoor air) and to map the results. This paper presents an atlas of up-to-date radon in soil and water levels for central and western part of Romania. The radon in soil map includes data from 2564 measurements carried out on-site, using Luk3C radon detector. The Luk-VR system was used to measure radon activity concentration from 2452 samples of drinking water. The average radon activity concentration was 29.3 kBq m-3 for soil gas, respectively 9.8 Bq l-1 for water dissolved air. Mapping of radon can be a useful tool to implement radon policies at both the national and local levels, defining priority areas for further study when land-use decisions must be made.

5.
J Environ Radioact ; 99(11): 1731-5, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18789562

RESUMEN

We propose a new method to measure the (222)Rn concentration in a closed bore-hole and to use the results for estimation of the diffusion parameter and the average radium content of the surrounding geological formations. In a closed bore-hole, only several meters from the surface, the radon concentration is rather constant (in the +/-15% range) under different meteorological conditions. The inflow of radon gas, after removing the radon from the bore-hole by dry nitrogen, shows characteristic time-dependence, which is determined by the diffusion parameter for radon in the surrounding environment. The experimental data were well described by a straightforward model calculation. From the results estimate can be given for the diffusion parameter and for the average radium content of the surrounding geological formation.


Asunto(s)
Geología , Radón/análisis , Meteorología , Nitrógeno/química
6.
Radiat Prot Dosimetry ; 181(1): 1-5, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29897577

RESUMEN

In many countries, caves can pose an economic interest for the authorities and stakeholders. The development of a show cave requires, apart from the conservation issues, to ensure the human safety by minimising the exposure to radon for cave personnel and visitors. Radon levels can vary widely from cave to cave, being directly correlated with different internal and external factors. It is therefore important to monitor radon levels before establishing the number of personnel required, so that they are not exposed to health-threatening levels of radiation. A long-term radon survey was carried out for this purpose in five show caves of Romania. The study pointed out the existence of high-radon potential areas inside the caves with concentrations reaching up to 4024 Bqm-3, thus posing radiological hazard to cave personnel and researchers who develop activities underground. Further research focused on personal dosimetry will be necessary for an efficient management of occupational risk.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Cuevas , Exposición a la Radiación/análisis , Monitoreo de Radiación/métodos , Radón/análisis , Humanos , Rumanía
7.
Clin Pharmacol Ther ; 103(3): 511-520, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28643328

RESUMEN

As drug development is extremely expensive, the identification of novel indications for in-market drugs is financially attractive. Multiple algorithms are used to support such drug repurposing, but highly reliable methods combining simulation of intracellular networks and machine learning are currently not available. We developed an algorithm that simulates drug effects on the flow of information through protein-protein interaction networks, and used support vector machine to identify potentially effective drugs in our model disease, psoriasis. Using this method, we screened about 1,500 marketed and investigational substances, identified 51 drugs that were potentially effective, and selected three of them for experimental confirmation. All drugs inhibited tumor necrosis factor alpha-induced nuclear factor kappa B activity in vitro, suggesting they might be effective for treating psoriasis in humans. Additionally, these drugs significantly inhibited imiquimod-induced ear thickening and inflammation in the mouse model of the disease. All results suggest high prediction performance for the algorithm.


Asunto(s)
Reposicionamiento de Medicamentos/métodos , Redes Reguladoras de Genes/genética , Dominios y Motivos de Interacción de Proteínas , Mapas de Interacción de Proteínas , Algoritmos , Animales , Línea Celular , Simulación por Computador , Dermatitis/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Oído Externo/patología , Humanos , Imiquimod , Aprendizaje Automático , Ratones , Ratones Endogámicos BALB C , FN-kappa B/efectos de los fármacos , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , ARN/biosíntesis , ARN/genética , Máquina de Vectores de Soporte , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
8.
Radiat Prot Dosimetry ; 177(1-2): 181-185, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28981907

RESUMEN

Measurements have been carried out using four types of passive detectors in four of the most popular show caves in Romania. Three types of detectors (RSKS, RadTrak and CD) were used for radon measurements and two (Raduet and CD) for thoron measurement. Activity concentrations in air were measured in the same locations for two seasons, autumn and winter. Measured values for the different caves varied between below detection limit (5 Bq m-3) and 4024 Bq m-3 for radon and from below 10 to 583 Bq m-3 for thoron. The results indicate a very good correlation between RSKS and RadTrak detectors (r = 0.96). The most significant difference between radon concentrations measured with different types of detectors (RSKS and CD) was higher than 150%. The study suggests that the activity concentration of radon in caves, measured using track detectors, could not be influenced by the type of detector used if the microclimate factor is acknowledged.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Cuevas , Exposición a Riesgos Ambientales/análisis , Monitoreo de Radiación/instrumentación , Radón/análisis , Límite de Detección , Hijas del Radón/análisis , Rumanía , Estaciones del Año
9.
Biochim Biophys Acta ; 925(3): 241-7, 1987 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-2956994

RESUMEN

The formation and composition of the insoluble heparin-fibronectin-collagen complex and its degradation by proteolysis was investigated. At fixed concentrations of the other molecular components of the complex, the maximal rate of complex formation, measured turbidimetrically, was reached at a concentration of 4 microM heparin and 0.9 microM collagen, while the rate of complex formation was linearly related to concentrations of fibronectin as high as 3 microM. Heparin was incorporated into the complex in a saturable manner, and was released in active anticoagulant form by plasmin but not by urokinase. The complex formation was inhibited by 5 mM calcium or 250 mM NaCl as well as by polybrene or spermin. It is suggested that fibronectin binds both heparin and collagen cooperatively to form an insoluble ternary complex of the extracellular matrix.


Asunto(s)
Colágeno , Fibrinolisina/farmacología , Fibronectinas , Heparina , Unión Competitiva , Calcio/farmacología , Precipitación Química , Bromuro de Hexadimetrina/farmacología , Humanos , Hidrólisis , Cinética , Unión Proteica , Cloruro de Sodio/farmacología , Solubilidad
10.
Genetics ; 156(4): 1901-12, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11102383

RESUMEN

The Ketel(D) dominant female-sterile mutations and their ketel(r) revertant alleles identify the Ketel gene, which encodes the importin-beta (karyopherin-beta) homologue of Drosophila melanogaster. Embryogenesis does not commence in the Ketel(D) eggs deposited by the Ketel(D)/+ females due to failure of cleavage nuclei formation. When injected into wild-type cleavage embryos, cytoplasm of the Ketel(D) eggs does not inhibit nuclear protein import but prevents cleavage nuclei formation following mitosis. The Ketel(+) transgenes slightly reduce effects of the Ketel(D) mutations. The paternally derived Ketel(D) alleles act as recessive zygotic lethal mutations: the Ketel(D)/- hemizygotes, like the ketel(r)/ketel(r) and the ketel(r)/- zygotes, perish during second larval instar. The Ketel maternal dowry supports their short life. The Ketel(D)-related defects originate most likely following association of the Ketel(D)-encoded mutant molecules with a maternally provided partner. As in the Ketel(D) eggs, embryogenesis does not commence in eggs of germline chimeras with ketel(r)/- germline cells and normal soma, underlining the dominant-negative nature of the Ketel(D) mutations. The ketel(r) homozygous clones are fully viable in the follicle epithelium in wings and tergites. The Ketel gene is not expressed in most larval tissues, as revealed by the expression pattern of a Ketel promoter-lacZ reporter gene.


Asunto(s)
Núcleo Celular/ultraestructura , Drosophila melanogaster/genética , Genes Dominantes , Genes de Insecto , Impresión Genómica , Proteínas de Insectos/genética , Proteínas Nucleares/genética , Alelos , Animales , Animales Modificados Genéticamente , Núcleo Celular/metabolismo , Quimera , Drosophila melanogaster/embriología , Drosophila melanogaster/metabolismo , Embrión no Mamífero/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Genes Letales , Genes Reporteros , Infertilidad Femenina/genética , Proteínas de Insectos/fisiología , Carioferinas , Larva , Microinyecciones , Proteínas Nucleares/fisiología , Fenotipo , Transporte de Proteínas/genética , Transgenes , Alas de Animales/citología , Cigoto
11.
J Chromatogr A ; 1079(1-2): 349-53, 2005 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-16038322

RESUMEN

In order to support high-throughput library purification, a novel UV triggered fraction collection method was developed in which a maximum-seeking-algorithm-driven, six-port valve collects the largest chromatographic peak. This straightforward strategy achieves the one sample-one fraction approach, thus resulting in a simpler and less error prone workup procedure. The effectiveness of this main component fraction collection method will be illustrated here by the results of the purification of compound libraries (altogether 6086 compounds, having an averaged success rate of 79.4%). Advanced applications, where the desired component differs from the main component, will also be discussed.


Asunto(s)
Fraccionamiento Químico/métodos , Mezclas Complejas/aislamiento & purificación , Biblioteca de Péptidos , Espectrofotometría Ultravioleta
12.
Leukemia ; 18(8): 1373-9, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15190260

RESUMEN

Cyclooxygenase (COX)-1 or -2 and specific prostaglandin (PG) synthases catalyze the formation of various PGs. We investigated the expression and activity of COX-1 and -2 during granulocyte-oriented maturation induced by all-trans-retinoic acid (ATRA) of NB4 cells, originated from a human acute promyelocytic leukemia (APL), and in blasts from APL patients. The expression of COX isoenzymes or prostaglandin synthases was also investigated in circulating granulocytes and human bone marrow. COX-1 was expressed and enzymatically active in NB4 cells and primary blasts. COX-1 mRNA and protein were induced by ATRA. COX-1 protein increased approximately 2-3.5-fold by culture day 3 in NB4 cells and primary blasts, while basal COX-2 expression was very low and unaffected by ATRA. COX-1-dependent PGE(2) biosynthesis increased during differentiation approx. 5-fold. Indomethacin and the selective COX-1 inhibitor SC-560, but not selective COX-2 inhibition, impaired NB4 differentiation, reducing NADPH-oxidase activity, CD11b and CD11c expression. The immunohistochemistry of granulocytes and myeloid precursors in the bone marrow showed a large prevalence of COX-1 as compared to COX-2. In conclusion, COX-1 is induced during ATRA-dependent maturation and appears to contribute to myeloid differentiation both in vitro and ex vivo, and COX-1 activity may potentiate the differentiation of human APL.Leukemia (2004) 18, 1373-1379. doi:10.1038/sj.leu.2403407 Published online 10 June 2004


Asunto(s)
Isoenzimas/biosíntesis , Leucemia Promielocítica Aguda/enzimología , Leucemia Promielocítica Aguda/patología , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Regulación hacia Arriba , Células Sanguíneas , Células de la Médula Ósea , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Dinoprostona/biosíntesis , Granulocitos/citología , Humanos , Isoenzimas/análisis , Isoenzimas/genética , Leucemia/enzimología , Leucemia/patología , Proteínas de la Membrana , Mielopoyesis/efectos de los fármacos , Prostaglandina-Endoperóxido Sintasas/análisis , Prostaglandina-Endoperóxido Sintasas/genética , ARN Mensajero/biosíntesis , Tretinoina/farmacología , Células Tumorales Cultivadas
13.
Cell Calcium ; 14(7): 531-8, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8402836

RESUMEN

In mixed platelet membrane vesicles the presence of two distinct endoplasmic reticulum-type calcium pump enzymes of 100 and 97 kD molecular mass has been demonstrated. We have previously shown that both calcium pumps were recognized by polyclonal anti-sarcoplasmic reticulum calcium pump antisera [11]. In the present work we studied the effects of several calcium pump inhibitors on active calcium transport and inositol trisphosphate-induced calcium release in these vesicles in an attempt to assign the two calcium pump isoenzymes to specific calcium pools. The effect of the PL/IM 430 inhibitory anti-calcium pump antibody was compared to that of other calcium pump inhibitors acting predominantly on the 100 and the 97 kD calcium pump isoforms, respectively. The PL/IM 430 antibody, which recognized the 97 kD pump on Western blots and 2,5-di-(tert-butyl)-1,4-benzohydroquinone, which inhibited phosphoenzyme formation of the same pump isoform, inhibited calcium accumulation predominantly into an inositol trisphosphate-releasable calcium pool. On the other hand, low concentration of thapsigargin, which inhibited phosphoenzyme formation mainly of the 100 kD pump isozyme, had a more pronounced effect on calcium uptake into an inositol trisphosphate-resistant pool. These data suggest that in platelets the 97 kD calcium pump isoform is likely to be associated with the inositol trisphosphate-sensitive calcium storage organelle.


Asunto(s)
Plaquetas/metabolismo , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , Calcio/metabolismo , Retículo Endoplásmico/enzimología , Inositol 1,4,5-Trifosfato/fisiología , Membranas Intracelulares/metabolismo , Isoenzimas/antagonistas & inhibidores , Anticuerpos Monoclonales/farmacología , Benzoquinonas/farmacología , Transporte Biológico , ATPasas Transportadoras de Calcio/inmunología , Compartimento Celular , Humanos , Indoles/farmacología , Isoenzimas/inmunología , Transducción de Señal , Terpenos/farmacología , Tapsigargina
14.
Cell Calcium ; 24(2): 129-35, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9803313

RESUMEN

Antibodies 5F10 and JA3 (raised against the erythrocyte Ca2+ pump) were used to identify hPMCA4b as the major form of the plasma membrane Ca2+ pump in human platelets and in three human megakaryoblastoid cell lines, MEG 01, DAMI and CHRF 288-11. 5F10 was used because it has been shown to recognize all known isoforms of the hPMCA and JA3 because it reacts exclusively with hPMCA4b [Caride A.J., Filoteo A.G., Enyedi A., Verma A.K., Penniston J.T. Detection of isoform 4 of the plasma membrane calcium pump in human tissues by using isoform-specific monoclonal antibodies. Biochem J 1996; 316: 353-359]. In addition to hPMCA4b, hPMCA1b was also detected in the megakaryoblastoid cells by using isoform-specific polyclonal antibodies. The apparent size of this isoform, however, was smaller than that seen in HeLa and COS-7 cell membranes indicating the presence of a modified form of hPMCA1b. In platelets, no evidence of the expression of hPMCA1b could be found. The amount of PMCA in these cells was compared with that of the constitutive form of the sarco/endoplasmic reticulum Ca2+ pump in non-muscle cells (SERCA2b) and also with the amount of PMCA in human erythrocytes. A very low level of the plasma membrane Ca2+ pump was found in platelets while in their precursor cells the expression of this Ca2+ pump was much more abundant. Whereas the expression level of PMCA decreased dramatically in mature human platelets, the expression of SERCA2b did not change substantially upon megakaryocytic differentiation.


Asunto(s)
Plaquetas/fisiología , ATPasas Transportadoras de Calcio/metabolismo , Megacariocitos/enzimología , Animales , Anticuerpos Monoclonales , Células COS/metabolismo , ATPasas Transportadoras de Calcio/inmunología , Proteínas de Transporte de Catión , Línea Celular , Eritrocitos/enzimología , Humanos , Isoenzimas , ATPasas Transportadoras de Calcio de la Membrana Plasmática , Sensibilidad y Especificidad
15.
Hypertension ; 35(1 Pt 1): 91-102, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10642281

RESUMEN

Gaining insight into nonmuscle Ca(2+) signaling requires basic knowledge of the major structures involved. We investigated the expression of platelet Ca(2+)ATPases in normal and hypertension-associated abnormal Ca(2+) signaling. First, overall identification of normotensive Wistar-Kyoto rat Ca(2+)ATPases was attempted by looking for newly described human platelet 3'-end alternatively spliced sarco/endoplasmic reticulum Ca(2+)ATPases (SERCA) 3b mRNA and plasma membrane Ca(2+)ATPase (PMCA) 1b and 4b proteins, in addition to SERCA2b and SERCA3a isoforms. For SERCAs, comparative analyses of human and Wistar-Kyoto rat SERCA3 platelet mRNA by reverse transcription-polymerase chain reaction (RT-PCR) followed by sequencing established that human platelets coexpressed SERCA3b and a third SERCA3c, while rat cells were devoid of them but expressed a still unknown splice variant that we termed rSERCA3b/3c. Its identification using 3'-end SERCA3 gene and rapid amplification of cDNA ends (RACE)-PCR studies showed that it results from an additional SERCA3 alternative splicing process, which uses a second alternative polyadenylation site located in the last intron. For PMCAs, with the use of gene-specific RT-PCR followed by sequencing and Western blotting using 5F10 monoclonal antibody, expression of human and rat platelet PMCA1b and PMCA4b was similar. Second, comparative analysis of these newly identified Ca(2+)ATPases and SERCA3a in age-matched spontaneously hypertensive rat platelets demonstrated (1) a marked downregulation of rSERCA3b/3c, which became null, and a 1.71-fold increase in SERCA3a and (2) an opposite regulation of the 2 PMCAs, namely, a 3.3-fold decrease in PMCA1b mRNA and a 3.7-fold increase in PMCA4b mRNA. Hence, platelets coexpress multiple, diverse, and species-specific Ca(2+)ATPases, including a novel fourth SERCA3. Moreover, expression of PMCA (1b and 4b), SERCA3a, and rSERCA3b/3c was modulated in rat hypertension. Hence, Ca(2+)ATPases should be regarded as constituting a new rational basis for the understanding of nonmuscle cell Ca(2+) signaling.


Asunto(s)
Plaquetas/enzimología , ATPasas Transportadoras de Calcio/sangre , ATPasas Transportadoras de Calcio/genética , Hipertensión/enzimología , Hipertensión/genética , Adulto , Empalme Alternativo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Señalización del Calcio , Membrana Celular/enzimología , Cartilla de ADN/genética , ADN Complementario/genética , Retículo Endoplásmico/enzimología , Células HeLa , Humanos , Técnicas In Vitro , Isoenzimas/sangre , Isoenzimas/genética , Datos de Secuencia Molecular , ARN Mensajero/sangre , ARN Mensajero/genética , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Retículo Sarcoplasmático/enzimología , Especificidad de la Especie
16.
FEBS Lett ; 423(2): 259-64, 1998 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-9512369

RESUMEN

Human platelets express several sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) isoenzymes: SERCA2b of 100 kDa apparent molecular mass and two distinct enzymes of 97 kDa, one of them identified as being the SERCA3a isoform. The molecular identity of the third enzyme specifically recognized by the PL/IM430 monoclonal antibody has remained elusive. First, the study of the 3'-end part of platelet SERCA3 mRNA, by means of RT-PCR amplification using sets of primers covering the N-3 to N (ultimate) exons of the human SERCA3 sequence, revealed the presence of two distinct mRNA sequences, SERCA3a and a longer variant. Second, this additional sequence was identified as SERCA3b and found to refer to the insertion of a new exon of 73 bp, located at bp 349 from the beginning of the intronic sequence, linking the penultimate (N-1) exon to the last exon (N) of the human SERCA3 gene. Third, a relationship between the expression of this SERCA3b mRNA and the PL/ IM430 recognizable SERCA protein was observed. SERCA3b mRNA was found to be absent in epithelial HeLa cells not recognized by the PL/IM430 antibody and the expression of this SERCA3b RNA species correlated with that of the SERCA protein recognized by PL/IM430 which was down-modulated in the platelet precursor megakaryocytic CHRF 288-11 cell line as well as upon in vitro lymphocyte activation. Taken together, these results strongly support the notion of the presence of the SERCA3b protein in human cells by showing SERCA3b mRNA in platelets and the fact that the protein corresponding to this mRNA species is very likely the 97 kDa protein recognized by the PL/IM430 antibody.


Asunto(s)
Especificidad de Anticuerpos , Plaquetas/enzimología , ATPasas Transportadoras de Calcio/inmunología , ATPasas Transportadoras de Calcio/metabolismo , Retículo Endoplásmico/enzimología , Isoenzimas/metabolismo , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , ATPasas Transportadoras de Calcio/genética , Exones , Células HeLa , Humanos , Isoenzimas/genética , Isoenzimas/inmunología , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Homología de Secuencia de Aminoácido
17.
AIDS Res Hum Retroviruses ; 10(7): 775-80, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7986582

RESUMEN

Ceramide, an intracellular lipid mediator of tumor necrosis factor alpha (TNF-alpha) action, was studied for its effects on the expression of the proviral human immunodeficiency virus type 1 genome in latently infected myelomonocytic cell lines U-1IIIB and OM-10.1. Ceramide treatment resulted in a 20- to 100-fold enhancement of HIV production in these cells. Ceramide also enhanced the expression of the chloramphenicol acetyltransferase gene directed by a human immunodeficiency virus type 1 long terminal repeat in transfected U-937 cells, indicating that ceramide acts at the level of viral transcription. These observations suggest that the TNF-ceramide signaling system may be involved in the regulation of HIV expression in certain myeloid cell types.


Asunto(s)
Ceramidas/farmacología , VIH-1/efectos de los fármacos , Línea Celular Transformada , Cloranfenicol O-Acetiltransferasa/biosíntesis , Duplicado del Terminal Largo de VIH/genética , VIH-1/genética , VIH-1/metabolismo , Humanos , Inmunohistoquímica , Factor de Necrosis Tumoral alfa/farmacología
18.
AIDS Res Hum Retroviruses ; 13(7): 545-54, 1997 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9135872

RESUMEN

GEM 91 (gene expression modulator) is a 25-mer oligonucleotide phosphorothioate complementary to the gag initiation site of HIV-1. GEM 91 has been studied in various in vitro cell culture models to examine inhibitory effects on different stages of HIV-1 replication. Experiments were focused on the binding of virions to the cell surface, inhibition of virus entry, reverse transcription (HIV DNA production), inhibition of steady state viral mRNA levels, inhibition of virus production from chronically infected cells, and inhibition of HIV genome packaging within virions. Experiments were also performed in vitro in an attempt to generate strains of HIV with reduced sensitivity to GEM 91. We observed sequence-dependent inhibition of virus entry/reverse transcription and a reduction in steady state viral RNA levels. We also observed sequence-independent inhibition of virion binding to cells and inhibition of virus production by chronically infected cells. Using in vitro methods that were successful in generating HIV strains with reduced sensitivity to AZT, we were unable to generate strains with reduced sensitivity to GEM 91.


Asunto(s)
Fármacos Anti-VIH/farmacología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , VIH-1/efectos de los fármacos , VIH-1/crecimiento & desarrollo , Oligodesoxirribonucleótidos Antisentido , Oligonucleótidos Antisentido/farmacología , Tionucleótidos/farmacología , Northern Blotting , Células Cultivadas , Replicación del ADN/efectos de los fármacos , Farmacorresistencia Microbiana , VIH-1/fisiología , Humanos , ARN Mensajero/metabolismo , ARN Viral/metabolismo , Transcripción Genética/efectos de los fármacos , Ensamble de Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Zidovudina/farmacología
19.
Thromb Res ; 47(5): 541-52, 1987 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-3672436

RESUMEN

The binding of antithrombin III, thrombin, thrombin-antithrombin III complex to endothelial cells was investigated. While the rate of the binding of thrombin to these cells was very rapid, that of antithrombin III was relatively slow and the thrombin-antithrombin III complex was intermediate. Binding kinetics indicated that antithrombin III, like thrombin, showed high affinity to endothelial cells; with a Kd of 3 X 10(-8) M and with 5 X 10(4) binding sites per cell. The dissociation of the inhibitor molecule was also rapid, i.e., approximately 70% bound antithrombin III was released in 2 minutes. Heparin, in a 100-fold molar excess to antithrombin III, or the modification of lysine residues of the inhibitor involved in the interaction with heparin, did not influence the association of antithrombin III with endothelial cells. In addition, antithrombin III did not compete with thrombin blocked in its active center for binding to endothelial cells. It is suggested that the binding sites of endothelial cells are different for thrombin and antithrombin III, and antithrombin III does not bind to these cells through its heparin binding domain.


Asunto(s)
Antitrombina III/metabolismo , Endotelio Vascular/metabolismo , Trombina/metabolismo , Animales , Sitios de Unión , Células Cultivadas , Cinética
20.
Talanta ; 42(3): 475-82, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18966255

RESUMEN

Organic vapours were measured by an array of piezoelectric crystal detectors. Quartz crystals were coated by different GC stationary phases. Four coated crystals were placed in an array and pattern recognition was used for identification of the compounds including acetone, benzene, chloroform and pentane. A computer program was developed for the measurement of the frequency changes and data processing. Pattern recognition method using feature extraction was applied for identification of analytes.

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