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Abstract
Klüver-Bucy syndrome (KBS) is a rare behavioral phenotype described in monkeys and humans that appears most often after bilateral temporal damage. The main features of KBS are compulsion to examine objects orally, increased sexual activity, placidity, hypermetamorphosis, visual agnosia, and amnesia. Cases in children are scarce, and the most frequently reported etiology is herpes encephalitis. Hyperorality (90%), hypersexuality (82%), and epilepsy (70%) were the most common features of the 51 cases reported in the literature to date. Carbamazepine, selective serotonin reuptake inhibitors (SSRIs), and neuroleptics have been used for symptomatic treatment with variable control. Corticosteroids or immunosupressive agents, such as rituximab, can be an option to use in some cases, according to etiology suspicion. Cognitive and behavioral disturbances after KBS are often severe, but improvement can occur over a long time and residual disabilities vary from major to fairly mild.We report two new encephalitis-associated pediatric patients and review all of the pediatric KBS cases in the literature to better describe the clinical features of this rare neurobehavioral condition.
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Affiliation(s)
- N Juliá-Palacios
- Pediatric Neurology, Vall d'Hebron Hospital, UAB, Barcelona, Spain
| | - S Boronat
- Pediatric Neurology, Vall d'Hebron Hospital, UAB, Barcelona, Spain.,Clinical Genetics, Vall d'Hebron Hospital, UAB, Barcelona, Spain
| | - I Delgado
- Pediatric Neuroradiology, Vall d'Hebron Hospital, UAB, Barcelona, Spain
| | - A Felipe
- Pediatric Neurology, Vall d'Hebron Hospital, UAB, Barcelona, Spain
| | - A Macaya
- Pediatric Neurology, Vall d'Hebron Hospital, UAB, Barcelona, Spain.,Pediatric Neurology Research Group, Vall d'Hebron Research Institute (VHIR), Universitat Autònoma de Barcelona, Barcelona, Catalonia, Spain
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Herrera M, Herrera JM, Cantatore S, Aguilar J, Felipe A, Fumuso E. Comparative histomorphological study of endometrium in mares. Anat Histol Embryol 2018; 47:153-158. [PMID: 29314167 DOI: 10.1111/ahe.12335] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/02/2017] [Indexed: 11/27/2022]
Abstract
Uterine acute post-breeding inflammation is a physiological tissue response to the entry of exogenous elements, with persistent endometritis being the main pathology responsible for subfertility in the mare (Equus ferus caballus; Linnaeus, 1758). Mares can be classified as susceptible or resistant to endometritis according to their ability to remove intrauterine fluid within 48 hr after experimental inoculation. Endometrial biopsy is a technique that is commonly used to establish the degree of lesions that can affect the fertility of the mare. Endometrial histomorphometry is an objective and highly precise diagnostic method. The aim of this study was to compare, during oestrus, the endometrial histomorphometry of mares previously classified as susceptible (SM) or resistant (RM) to endometritis. Endometrial biopsies from 24 mares at the oestrus phase of the cycle were obtained. For the histomorphometric analysis, samples were histologically processed and subjected to routine Haematoxylin-Eosin staining. For the evaluation, the variables were considered as follows: 1-Height of the lining and glandular epithelia (Lining SM = 15.9 μm vs. RM = 13.3 μm; Glandular SM = 15.0 μm vs. RM = 13.0 μm); 2-Perpendicular diameters of endometrial glands (SM = 51.3 μm vs. RM = 44.8 μm); 3-Number of endometrial glands per field (SM = 24.8 glands/field vs. RM = 20.5 glands/field). The results from this study suggest the existence of a relationship between the studied characteristics and the susceptibility/resistance to post-breeding endometritis in mares. Thus, increased epithelial height, greater glandular density and greater development of the glands during oestrus would be related to a higher susceptibility to endometritis.
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Affiliation(s)
- M Herrera
- Facultad de Ciencias Veterinarias, Laboratorio de Clínica y Reproducción Equina, CIVETAN, UNICEN, Tandil, Argentina.,Facultad de Ciencias Veterinarias, Área de Ciencias Morfológicas, UNICEN, Tandil, Argentina
| | - J M Herrera
- Facultad de Ciencias Veterinarias, Área de Ciencias Morfológicas, UNICEN, Tandil, Argentina
| | - S Cantatore
- Facultad de Ciencias Veterinarias, Laboratorio de Clínica y Reproducción Equina, CIVETAN, UNICEN, Tandil, Argentina.,Facultad de Ciencias Veterinarias, CONICET, CIVETAN, UNICEN, Tandil, Argentina
| | - J Aguilar
- Facultad de Agronomía y Veterinaria, Laboratorio de Producción Equina, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - A Felipe
- Facultad de Ciencias Veterinarias, Área de Ciencias Morfológicas, UNICEN, Tandil, Argentina
| | - E Fumuso
- Facultad de Ciencias Veterinarias, Laboratorio de Clínica y Reproducción Equina, CIVETAN, UNICEN, Tandil, Argentina
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Felipe A, Martín N, Miranda P, Pardo L. Statistical inference in constrained latent class models for multinomial data based on $$\phi $$ ϕ -divergence measures. ADV DATA ANAL CLASSI 2017. [DOI: 10.1007/s11634-017-0289-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gomez-Garcia de la Banda M, Julia N, Felipe A, Sanchez-Montañez A, Balcells J, Pujol M, Soler P, Rodrigo C, Floriano B, Lopez J, Macaya A, Munell F. Two recent pediatric cases of severe polio-like paralysis caused by enterovirus D68 infection in Spain. Neuromuscul Disord 2016. [DOI: 10.1016/j.nmd.2016.06.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Felipe A, Miranda P, Pardo L. Minimum ϕ -Divergence Estimation in Constrained Latent Class Models for Binary Data. Psychometrika 2015; 80:1020-1042. [PMID: 25724663 DOI: 10.1007/s11336-015-9450-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 02/12/2015] [Indexed: 06/04/2023]
Abstract
The main purpose of this paper is to introduce and study the behavior of minimum ϕ -divergence estimators as an alternative to the maximum-likelihood estimator in latent class models for binary items. As it will become clear below, minimum ϕ -divergence estimators are a natural extension of the maximum-likelihood estimator. The asymptotic properties of minimum ϕ -divergence estimators for latent class models for binary data are developed. Finally, to compare the efficiency and robustness of these new estimators with that obtained through maximum likelihood when the sample size is not big enough to apply the asymptotic results, we have carried out a simulation study.
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Affiliation(s)
- A Felipe
- Department of Statistics and Operations Research, Faculty of Mathematics, Complutense University of Madrid, 28040 , Madrid, Spain
| | - P Miranda
- Department of Statistics and Operations Research, Faculty of Mathematics, Complutense University of Madrid, 28040 , Madrid, Spain.
| | - L Pardo
- Department of Statistics and Operations Research, Faculty of Mathematics, Complutense University of Madrid, 28040 , Madrid, Spain
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Poncet L, Bellesia B, Oliva AB, Boter Rebollo E, Cornelis M, Cornella Medrano J, Harrison R, Bue AL, Moreno A, Foussat A, Felipe A, Echeandia A, Barutti A, Caserza B, Barbero P, Stenca S, Da Re A, Silva Ribeiro J, Brocot C, Benaoun S. EU ITER TF coil: Dimensional metrology, a key player in the Double Pancake integration. Fusion Engineering and Design 2015. [DOI: 10.1016/j.fusengdes.2015.06.073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Vidigal V, da Silva T, Pimenta C, Oliveira J, Felipe A, Forones N. P-220 Genetic Polymorphism of Vitamin D Receptor BsmI, ApaI and CYP27B1, CYP24A1 genes and the risk of colorectal cancer. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv233.217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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da Silva T, Vidigal V, Felipe A, Artigiani Neto R, Saad S, Forones N. P-192 DNA methylation profile of APC and DKK2 genes as biomarkers in colorectal cancer patients. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv233.190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Teruel M, Felipe A, Herrera M, Dopazo J, Díaz M, Gómez S, Eyheramendy V, Guerrero M. Una Propuesta de Evaluación Formativa en Ciencias Morfológicas. INT J MORPHOL 2014. [DOI: 10.4067/s0717-95022014000400014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Goya M, Cespedes MC, Camba F, Capote S, Felipe A, Reixachs A, Medina D, Gorraiz V, Pin S, Halachian C, Gracia A, Perapoch J, Cabero L, Carreras E. Antenatal corticosteroids and perinatal outcomes in infants born at 23-25 weeks of gestation. J Matern Fetal Neonatal Med 2014; 28:2084-9. [PMID: 25367557 DOI: 10.3109/14767058.2014.978280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES To evaluate the perinatal results of infants born between 23 and 25.6 weeks of gestation. METHODS Medical charts of all women giving birth prematurely (23-25.6 w) from January 2005 to December 2011 were retrospectively reviewed. Cases of malformed infants or deliveries elsewhere were excluded. RESULTS 198 infants were included. Chorioamnionitis occurred in 86 (43.4%) of the whole group: 26 (86.7%) in the 23-week; 35 (53.8%) in the 24-week and 25 (24.3%) in the 25-week groups. Foetal maturation with antenatal corticosteroids was complete in 119 cases (60.1%): 4 (13.3%) in the 23-week; 35 (53.8%) in the 24-week and 80 (77.7%) in the 25-week groups. Foetal death at birth occurred in 22 cases (11%) and 61 newborns (30.8%) died in the neonatal period. Of the 106 survivors with 2 years complete follow-up, 45 infants (42.4%) did not present sequelae; 16 infants (15.1%) had severe sequelae. A 66.6% (4) of infants born at 23 weeks of gestation did not present sequelae compared with a 32.3% (11) at 24 weeks and 45.4% (30) at 25 weeks. CONCLUSIONS The chorioamnionitis rate was higher when gestational age was lower. The foetal maturation rate was higher when gestational age was higher. A low severe sequelae rate was observed in the whole series, particularly in the 23-week group where the rate was lower than expected; however, these results could have been influenced by the small size of the 23-week group.
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Affiliation(s)
- M Goya
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - M C Cespedes
- b Department of Pediatrics, Neonatal Intensive Care Unit , Hospital Vall d'Hebron , Barcelona , Spain
| | - F Camba
- b Department of Pediatrics, Neonatal Intensive Care Unit , Hospital Vall d'Hebron , Barcelona , Spain
| | - S Capote
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - A Felipe
- b Department of Pediatrics, Neonatal Intensive Care Unit , Hospital Vall d'Hebron , Barcelona , Spain
| | - A Reixachs
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - D Medina
- b Department of Pediatrics, Neonatal Intensive Care Unit , Hospital Vall d'Hebron , Barcelona , Spain
| | - V Gorraiz
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - S Pin
- b Department of Pediatrics, Neonatal Intensive Care Unit , Hospital Vall d'Hebron , Barcelona , Spain
| | - C Halachian
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - A Gracia
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - J Perapoch
- b Department of Pediatrics, Neonatal Intensive Care Unit , Hospital Vall d'Hebron , Barcelona , Spain
| | - L Cabero
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
| | - E Carreras
- a Department of Obstetrics and Gynecology, Maternal-Fetal Medicine Unit , Hospital Vall d'Hebron , Barcelona , Spain and
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Artigas C, Navea A, López-Murcia MM, Felipe A, Desco C, Artigas JM. Spectral transmission of the pig lens: effect of ultraviolet A+B radiation. J Fr Ophtalmol 2014; 37:773-9. [PMID: 25280767 DOI: 10.1016/j.jfo.2014.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 06/06/2014] [Accepted: 06/11/2014] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the spectral transmission curve of the crystalline lens of the pig. To analyse how this curve changes when the crystalline lens is irradiated with ultraviolet A+B radiation similar to that of the sun. To compare these results with literature data from the human crystalline lens. PROCEDURES We used crystalline lenses of the common pig from a slaughterhouse, i.e. genetically similar pigs, fed with the same diet, and slaughtered at six months old. Spectral transmission was measured with a Perkin-Elmer Lambda 35 UV/VIS spectrometer. The lenses were irradiated using an Asahi Spectra Lax-C100 ultraviolet source, which made it possible to select the spectral emission band as well as the intensity and exposure time. RESULTS The pig lens transmits all the visible spectrum (95%) and lets part of the ultraviolet A through (15%). Exposure to acute UV (A+B) irradiation causes a decrease in its transmission as the intensity or exposure time increases: this decrease is considerable in the UV region. CONCLUSIONS We were able to determine the mean spectral transmission curve of the pig lens. It appears to be similar to that of the human lens in the visible spectrum, but different in the ultraviolet. Pig lens transmission is reduced by UV (A+B) irradiation and its transmission in the UV region can even disappear as the intensity or exposure time increases. An adequate exposure intensity and time of UV (A+B) radiation always causes an anterior subcapsular cataract (ASC).
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Affiliation(s)
- C Artigas
- Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, Avda Seminario s/n, 46113 Moncada (Valencia), Spain
| | - A Navea
- Fisabio Oftalmología Médica (FOM), Bifurcación Pío Baroja-General Avilés, s/n, 46015 Valencia, Spain
| | - M-M López-Murcia
- Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, Avda Seminario s/n, 46113 Moncada (Valencia), Spain
| | - A Felipe
- Departamento de Óptica, Facultad de Física, Universidad de valencia, C/Dr Moliner, 50, 46100 Burjassot (Valencia), Spain; Fisabio Oftalmología Médica (FOM), Bifurcación Pío Baroja-General Avilés, s/n, 46015 Valencia, Spain
| | - C Desco
- Fisabio Oftalmología Médica (FOM), Bifurcación Pío Baroja-General Avilés, s/n, 46015 Valencia, Spain
| | - J-M Artigas
- Fisabio Oftalmología Médica (FOM), Bifurcación Pío Baroja-General Avilés, s/n, 46015 Valencia, Spain; Departamento de Óptica, Facultad de Física, Universidad de valencia, C/Dr Moliner, 50, 46100 Burjassot (Valencia), Spain.
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Abstract
PURPOSE After determining the mean intensity of ultraviolet radiation to which the human eye is exposed at Mediterranean latitudes, this data is used to evaluate the efficacy of the ultraviolet filters incorporated into various intraocular lenses. METHODS Ultraviolet radiation measured at Mediterranean latitudes was used as a reference for the theoretical calculation of the amount of radiation to which the human eye is exposed. The spectral transmission curve from 290 to 380 nm was measured for 10 IOLs using a UV/VIS Perkins-Elmer Lambda 800 spectrometer. RESULTS At Mediterranean latitudes, at sea level, with a mean annual solar irradiation of 50 j/cm(2), the human eye receives a quantity of UVA and UVB that is lower than the threshold toxic dose for the rabbit crystalline lens (93 j/cm(2) for UVA and 6.45 j/cm(2) for UVB). However, at higher altitudes and with albedo approaching 0.9 (fresh snow), the amount of radiation increases, with duration of exposure potentially playing a significant role. The UV filters incorporated into the IOLs studied are, in general, protective against such levels of radiation. CONCLUSION At Mediterranean latitudes, at sea level, the amount of UV radiation to which our eyes are exposed is insufficient to damage the crystalline lens; however, at higher altitudes, the risk of such damage exists. UV filters incorporated into intraocular lenses are generally effective, since they filter all radiation with wavelengths under 380 nm.
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Affiliation(s)
- J M Artigas
- Fundación oftalmológica del Mediterráneo (FOM), bifurcación Pío Baroja-General Avilés, s/n. E46015 Valencia, Spain.
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Felipe A, Bielanska J, Comes N, Vallejo A, Roig S, Ramon y Cajal S, Condom E, Hernandez-Losa J, Ferreres J. Targeting the Voltage-Dependent K+ Channels Kv1.3 and Kv1.5 as Tumor Biomarkers for Cancer Detection and Prevention. Curr Med Chem 2012; 19:661-74. [DOI: 10.2174/092986712798992048] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 11/03/2011] [Indexed: 11/22/2022]
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Bielanska J, Hernández-Losa J, Pérez-Verdaguer M, Moline T, Somoza R, Ramón Y Cajal S, Condom E, Ferreres JC, Felipe A. Voltage-dependent potassium channels Kv1.3 and Kv1.5 in human cancer. Curr Cancer Drug Targets 2010; 9:904-14. [PMID: 20025600 DOI: 10.2174/156800909790192400] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Membrane ion channels participate in cancerous processes such as proliferation, migration and invasion, which contribute to metastasis. Increasing evidence indicates that voltage-dependent K(+) (Kv) channels are involved in the proliferation of many types of cells, including tumor cells. Kv channels have generated immense interest as a promising tool for developing new anti-tumor therapies. Therefore, the identification of potential biomarkers and therapeutic targets in specific cancers is an important prerequisite for the treatment. Since Kv1.3 and Kv1.5 are involved in the proliferation of many mammalian cells, we aimed to study the expression of Kv1.3 and Kv1.5 in a plethora of human cancers. Thus, tissues from breast, stomach, kidney, bladder, lung, skin, colon, ovary, pancreas, brain, lymph node, skeletal muscle and some of their malignant counterparts have been analyzed. Whereas Kv1.3 expression was either decreased or did not change in most tumors, Kv1.5 was overexpressed. However, the presence of Kv1.3 was mostly associated with inflammatory lymphoplasmocytic cells. Independent of the suitability of individual channels as therapeutic targets, the identification of a Kv phenotype from tumor specimens could have a diagnostic value of its own. Our results demonstrate that Kv1.5, and to some extent Kv1.3, are aberrantly expressed in a number of human cancers. These channels could serve both as novel markers of the metastatic phenotype and as potential new therapeutic targets. The concept of Kv channels as therapeutic targets or prognostic biomarkers attracts increasing interest and warrants further investigation.
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Affiliation(s)
- J Bielanska
- Molecular Physiology laboratory, Departament de Bioquímica i Biologia Molecular, Facultat de Biología, Universitat de Barcelona, E-08028 Barcelona, Spain
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Felipe A, Pardo L. New family of estimators for the loglinear model of quasi-independence based on power-divergence measures. J STAT COMPUT SIM 2007. [DOI: 10.1080/10629360600890154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Argilés JM, Busquets S, Felipe A, López-Soriano FJ. Muscle wasting in cancer and ageing: cachexia versus sarcopenia. Adv Gerontol 2006; 18:39-54. [PMID: 16676797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Muscle wasting during cancer and ageing share many common metabolic pathways and mediators. Due to the size of the population involved, both cancer cachexia and ageing sarcopenia may represent targets for future promising clinical investigations. Cancer cachexia is a syndrome characterized by a marked weight loss, anorexia, asthenia and anemia. In fact, many patients who die with advanced cancer suffer from cachexia. The degree of cachexia is inversely correlated with the survival time of the patient and it always implies a poor prognosis. In recent years, age-related diseases and disabilities have become of major health interest and importance. This holds particularly for muscle wasting, also known as sarcopenia that decreases the quality of life of the geriatric population, increasing morbidity and decreasing life expectancy. The cachectic factors (associated with both depletion of fat stores and muscular tissue) can be divided into two categories: of tumour origin and humoural factors. In conclusion, more research should be devoted to the understanding of muscle wasting mediators, both in cancer and ageing, in particular the identification of common mediators may prove as a good therapeutic strategy for both prevention and treatment of wasting both in disease and during healthy ageing.
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Affiliation(s)
- J M Argilés
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Diagonal 645, 08028 Barcelona, Spain.
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Barriuso A, Monzón J, Sánchez-Soto L, Felipe A. Comparing omnidirectional reflection from periodic and quasiperiodic one-dimensional photonic crystals. Opt Express 2005; 13:3913-3920. [PMID: 19495300 DOI: 10.1364/opex.13.003913] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We determine the range of thicknesses and refractive indices for which omnidirectional reflection from quasiperiodic dielectric multilayers occurs. By resorting to the notion of area under the transmittance curve, we assess in a systematic way the performance of the different Fibonacci multilayers.
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Ródenas J, Zarza I, Burgos MC, Felipe A, Sánchez-Mayoral ML. Developing a virtual reality application for training nuclear power plant operators: setting up a database containing dose rates in the refuelling plant. Radiat Prot Dosimetry 2004; 111:173-180. [PMID: 15266073 DOI: 10.1093/rpd/nch043] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Operators in Nuclear Power Plants can receive high doses during refuelling operations. A training programme for simulating refuelling operations will be useful in reducing the doses received by workers as well as minimising operation time. With this goal in mind, a virtual reality application is developed within the framework of the CIPRES project. The application requires doses, both instantaneous and accumulated, to be displayed at all times during operator training. Therefore, it is necessary to set up a database containing dose rates at every point in the refuelling plant. This database is based on radiological protection surveillance data measured in the plant during refuelling operations. Some interpolation routines have been used to estimate doses through the refuelling plant. Different assumptions have been adopted in order to perform the interpolation and obtain consistent data. In this paper, the procedures developed to set up the dose database for the virtual reality application are presented and analysed.
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Affiliation(s)
- J Ródenas
- Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Apartado 22012 E-46071 Valencia, Spain.
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Coma M, Vicente R, Tsevi I, Grande M, Tamkun MM, Felipe A. Different Kv2.1/Kv9.3 heteromer expression during brain and lung post-natal development in the rat. J Physiol Biochem 2002; 58:195-203. [PMID: 12744302 DOI: 10.1007/bf03179857] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The Kv2.1/Kv9.3 heteromer generates an O2 sensitive potassium channel and induces a slow deactivation that has important consequences for brain and lung physiology. We examined the developmental regulation of Kv2.1 and Kv9.3 mRNAs in brain and lung. Both genes followed parallel expression patterns in brain, increasing progressively through post-natal life. In lung, however, the expression of the two genes followed opposite trends: Kv2.1 transcripts decreased, while Kv9.3 mRNA increased. The Kv9.3/Kv2.1 ratio shows that while in brain the expression of both genes followed a similar pattern, the relative abundance of Kv9.3 increased steadily through post-natal life in lung. Furthermore, there is selective regulation of gene expression during the suckling-weaning transition. Our results suggest that different Kv9.3/Kv2.1 ratios could have physiological implications in both organs during post-natal development, and that diet composition and selective tissue-specific insulin regulation modulate the expression of Kv2.1 and Kv9.3.
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Affiliation(s)
- M Coma
- Laboratori de Fisiologia Molecular, Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, 08028 Barcelona, Spain
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Pinochet J, Fernández C, Cunill M, Torrents J, Felipe A, López M, Lastra B, Penyalver R. RESPONSE OF NEW INTERSPECIFIC HYBRIDS FOR PEACH TO ROOT-KNOT AND LESION NEMATODES, AND CROWN GALL. ACTA ACUST UNITED AC 2002. [DOI: 10.17660/actahortic.2002.592.99] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Fuster G, Vicente R, Coma M, Grande M, Felipe A. One-step reverse transcription polymerase chain reaction for semiquantitative analysis of mRNA expression. Methods Find Exp Clin Pharmacol 2002; 24:253-9. [PMID: 12168500 DOI: 10.1358/mf.2002.24.5.802301] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Analysis of mRNA expression is one of the main targets of scientific research. However, its quantification can be difficult, especially when dealing with low-expression mRNAs (ionic channels, carriers, receptors, etc.) or when only small samples are available (human biopsies). Here we suggest an easy, rapid and reliable method to assess semiquantitative changes in mRNA that combines several technical improvements: i) one-step reverse transcription polymerase chain reaction (RT-PCR) from total RNA; ii) addition of ethidium bromide to the gel, which provides a more homogeneous binding to DNA; iii) direct capture of the gel image using a charged-coupled device camera and then saving the image on computer before quantification, which increases resolution and thus improves and shortens the analysis; and iv) the use of 18S rRNA as a control, which is especially useful when samples from activation, differentiation and proliferation models are used. The technique was validated by checking the system conditions of image capturing and quantification. This was corroborated by a study of Kvl.3 ion channel expression in the brain. In these conditions, the wide range of PCR cycles and total RNA allows us to correlate relative gene expression and direct input of the target gene.
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Affiliation(s)
- G Fuster
- Membrane Protein Molecular Physiology Group, Department of Biochemistry and Molecular Biology, Universitat de Barcelona, Barcelona, Spain
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25
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Soler C, García-Manteiga J, Valdés R, Xaus J, Comalada M, Casado FJ, Pastor-Anglada M, Celada A, Felipe A. Macrophages require different nucleoside transport systems for proliferation and activation. FASEB J 2001; 15:1979-88. [PMID: 11532978 DOI: 10.1096/fj.01-0022com] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
To evaluate the mechanisms involved in macrophage proliferation and activation, we studied the regulation of the nucleoside transport systems. In murine bone marrow-derived macrophages, the nucleosides required for DNA and RNA synthesis are recruited from the extracellular medium. M-CSF induced macrophage proliferation and DNA and RNA synthesis, whereas interferon gamma (IFN-gamma) led to activation, blocked proliferation, and induced only RNA synthesis. Macrophages express at least the concentrative systems N1 and N2 (CNT2 and CNT1 genes, respectively) and the equilibrative systems es and ei (ENT1 and ENT2 genes, respectively). Incubation with M-CSF only up-regulated the equilibrative system es. Inhibition of this transport system blocked M-CSF-dependent proliferation. Treatment with IFN-gamma only induced the concentrative N1 and N2 systems. IFN-gamma also down-regulated the increased expression of the es equilibrative system induced by M-CSF. Thus, macrophage proliferation and activation require selective regulation of nucleoside transporters and may respond to specific requirements for DNA and RNA synthesis. This report also shows that the nucleoside transporters are critical for macrophage proliferation and activation.
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Affiliation(s)
- C Soler
- Departament de Fisiologia (Biologia del Macròfag) and Fundació August Pi i Sunyer, Campus de Bellvitge, E-08028 Barcelona, Spain
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26
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Soler C, Valdés R, Garcia-Manteiga J, Xaus J, Comalada M, Casado FJ, Modolell M, Nicholson B, MacLeod C, Felipe A, Celada A, Pastor-Anglada M. Lipopolysaccharide-induced apoptosis of macrophages determines the up-regulation of concentrative nucleoside transporters Cnt1 and Cnt2 through tumor necrosis factor-alpha-dependent and -independent mechanisms. J Biol Chem 2001; 276:30043-9. [PMID: 11346649 DOI: 10.1074/jbc.m101807200] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In murine bone marrow macrophages, lipopolysaccharide (LPS) induces apoptosis through the autocrine production of tumor necrosis factor-alpha (TNF-alpha), as demonstrated by the fact that macrophages from TNF-alpha receptor I knock-out mice did not undergo early apoptosis. In these conditions LPS up-regulated the two concentrative high affinity nucleoside transporters here shown to be expressed in murine bone marrow macrophages, concentrative nucleoside transporter (CNT) 1 and 2, in a rapid manner that is nevertheless consistent with the de novo synthesis of carrier proteins. This effect was not dependent on the presence of macrophage colony-stimulating factor, although LPS blocked the macrophage colony-stimulating factor-mediated up-regulation of the equilibrative nucleoside transport system es. TNF-alpha mimicked the regulatory response of nucleoside transporters triggered by LPS, but macrophages isolated from TNF-alpha receptor I knock-out mice similarly up-regulated nucleoside transport after LPS treatment. Although NO is produced by macrophages after LPS treatment, NO is not involved in these regulatory responses because LPS up-regulated CNT1 and CNT2 transport activity and expression in macrophages from inducible nitric oxide synthase and cationic amino acid transporter (CAT) 2 knock-out mice, both of which lack inducible nitric oxide synthesis. These data indicate that the early proapoptotic responses of macrophages, involving the up-regulation of CNT transporters, follow redundant regulatory pathways in which TNF-alpha-dependent- and -independent mechanisms are involved. These observations also support a role for CNT transporters in determining extracellular nucleoside availability and modulating macrophage apoptosis.
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Affiliation(s)
- C Soler
- Departament de Fisiologia (Biologia del Macròfag), Universitat de Barcelona, Barcelona, Spain
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27
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Abstract
BACKGROUND/AIMS The pattern of nucleoside transporter expression in hepatocytes was studied in the developing rat liver. METHODS Hepatocytes isolated from fetuses, neonates and adult rats were used for uridine uptake measurements and concentrative nucleoside transporter (CNT) expression. RESULTS Adult hepatocytes showed the highest Na-dependent uridine uptake, but fetal hepatocytes exhibited a significant NBTI-sensitive component of equilibrative Na+-independent transport, which was either negligible or absent in neonatal and adult rat hepatocytes. Low Na+-dependent uridine uptake was associated with low amounts of CNT1 and CNT2 transporter proteins, both with apparent Km values in the low micromolar range. Hepatocyte primary cultures from 20-day-old fetuses showed very low amounts of CNT2 mRNA, and expressed both carrier proteins. Incubation of fetal hepatocytes with dexamethasone and T3 resulted in a significant increase in Na+-dependent uridine uptake and an accumulation of the CNT2 protein and mRNA. CONCLUSIONS The expression of concentrative nucleoside carriers in hepatocytes from developing rat liver is developmentally regulated. Addition of endocrine factors known to induce differentiation of fetal hepatocytes results in selective up-regulation of CNT2 expression.
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Affiliation(s)
- B del Santo
- Department de Bioquímica i Biologia Molecular, Universitat de Barcelona, Barcelona, Spain
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28
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Bink H, Carbó N, Felipe A, López-Soriano FJ, Argilés JM. Hepatic transport of gluconeogenic substrates during tumor growth in the rat. Cancer Invest 2001; 19:248-55. [PMID: 11338881 DOI: 10.1081/cnv-100102551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Hepatic gluconeogenic substrates (alanine, lactate, and glycerol) transport have been studied in liver plasma membrane vesicles from rats bearing the ascitic tumor Yoshida AH-130 hepatoma. Hepatic alanine uptake was increased in membrane vesicles from tumor-bearing animals as compared with those isolated from non-tumor-bearing controls. Although no changes were observed in relation with KM (2.19 and 2.10 mM for control and tumor groups, respectively), the presence of the tumor caused a clear increase in Vmax (3.07 and 5.04 nmol alanine/mg protein, respectively). The time course of lactate uptake showed no differences between the tumor-bearing animals and their corresponding controls. Both time course and kinetic experiments showed that liver glycerol uptake was due to passive diffusion and therefore cannot contribute to explain the enhanced utilization of this hepatic gluconeogenic substrate during tumor growth. The results suggest that hepatic alanine uptake may be an important factor accounting for its increased utilization for glucose synthesis in tumor-bearing rats.
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Affiliation(s)
- H Bink
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
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29
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Valdés R, Ortega MA, Casado FJ, Felipe A, Gil A, Sánchez-Pozo A, Pastor-Anglada M. Nutritional regulation of nucleoside transporter expression in rat small intestine. Gastroenterology 2000; 119:1623-30. [PMID: 11113083 DOI: 10.1053/gast.2000.20183] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS Concentrative nucleoside transporters CNT1 (pyrimidine preferring) and CNT2 (purine preferring) may be involved in the uptake of nucleoside-derived drugs used in antiviral and chemical therapies. The possibility that nucleoside carrier isoform expression is modulated by nutrient availability has been studied. METHODS CNT1 and CNT2 tissue distribution was determined by Western blot analysis. The effect of 48-hour starvation on CNT expression was then studied. Nucleoside transporter expression and uptake activity were measured in jejunal brush border plasma membrane vesicles from fed and starved rats. The expression of nucleoside transporters was later determined in a second model of nutrient deficiency: rats fed a purified diet with or without nucleotides for 10 days. RESULTS CNT1 and CNT2 nucleoside transporters were expressed in a wider variety of tissues than expected from messenger RNA distribution analysis. CNT1 was sensitive to nutrient availability in small intestine and, accordingly, jejunal brush border membrane vesicles from 48-hour-fasted rats showed increased expression of CNT1 and enhanced Na(+)-dependent thymidine and gemcitabine uptake. This effect was mimicked by feeding semipurified diets lacking nucleotides. CONCLUSIONS Substrate availability modulates nucleoside transporter expression (CNT1) in rat jejunum in vivo.
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Affiliation(s)
- R Valdés
- Departament de Bioquímica i Biologia Molecular, University of Barcelona, Barcelona, Spain
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30
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Abstract
Evidence that hepatoma cell lines show differential expression of concentrative nucleoside transporters (CNT1 and CNT2) prompted us to study the transporter proteins in 2 models of hepatocarcinogenesis, the chemically induced Solt and Farber model and the albumin-SV40 large T antigen (Alb-SV40) transgenic rat. CNT1 expression was lower in tumor biopsy specimens from Alb-SV40 rat livers than in normal tissue. Immunocytochemistry revealed that the CNT1 protein was indeed absent in the tumor lesions. CNT1 was also absent in a cell line, L25, derived from the Alb-SV40 transgenic rat liver tumors, whereas another cell line, L37, derived from the normal-appearing parenchyma, retained the expression of both carrier isoforms. The protein expression correlated with the nucleoside transport properties of these cell lines. Moreover, although CNT2 expression was highly dependent on the growth characteristics of the 2 cell lines, as was CNT1 (albeit to a lower extent) in L37 cells, it was not expressed in L25 cells at any stage of cell growth. In contrast to the transgenic model of hepatocarcinogenesis, in the chemically induced tumors the expression of CNT2 was lower, although still detectable. In summary, these data indicate that hepatocarcinogenesis leads to a selective loss or diminished expression of nucleoside carrier isoforms, a feature that may be relevant to our understanding of the molecular basis of the bioavailability of those drugs that are nucleoside derivatives and may be substrates of these carriers. The transport properties and isoform-expression profile of the L25 and L37 cell lines make them suitable hepatocyte culture models with which to study nucleoside transport processes and drug sensitivity.
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Affiliation(s)
- Y Dragan
- McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine, University of Wisconsin, Madison, WI, USA
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31
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Abstract
Activation of human B lymphocytes by lipopolysaccharide (LPS) or phorbol 12-myristate 13-acetate (PMA) results in the differential regulation of nucleoside uptake [Soler, C., Felipe, A., Mata, J. F., Casado, F. J., Celada, A., Pastor-Anglada, M. (1998) J. Biol. Chem. 273, 26939-26945]. Because nitric oxide (NO) is involved in the modulation of the apoptotic response of B cells, the effects of NO on the regulatory responses of these transport systems to phorbol esters has been studied in Raji cells by a combination of approaches that involve arginine depletion, inhibition of nitric oxide synthase, and non-enzymatic production of NO using a donor. Human B lymphocytes express three transport systems involved in nucleoside uptake: N1 and N5, which are concentrative and Na+-dependent, and the nitrobenzylthioinosine-sensitive equilibrative system es. Raji cells do not express significant amounts of iNOS mRNA or protein; thus, NO production is presumably constitutive. The data are consistent with a role of NO in maintaining the basal transport activities of the three systems: N1, N5, and es. However, the up-regulatory effect of PMA on N1 and N5 does not require NO, whereas the inhibition of es transport activity does. In summary, NO differentially modulates nucleoside transport systems in activated human B lymphocytes and thus, NO may also be involved in the regulation of nucleoside (i.e., adenosine) disposal by activated B cells.
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Affiliation(s)
- C Soler
- Departament de Fisiologia (Immunologia) and Fundació Pi i Sunyer, Universitat de Barcelona, Spain
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32
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Abstract
Hypoxic pulmonary vasoconstriction is initiated by inhibiting one or more voltage-gated potassium (Kv) channel in the vascular smooth muscle cells (VSMCs) of the small pulmonary resistance vessels. Although progress has been made in identifying which Kv channel proteins are expressed in pulmonary arterial (PA) VSMCs, there are conflicting reports regarding which channels contribute to the native O(2)-sensitive K(+) current. In this study, we examined the effects of hypoxia on the Kv1.2, Kv1.5, Kv2.1, and Kv9.3 alpha subunits expressed in mouse L cells using the whole-cell patch-clamp technique. Hypoxia (PO(2)= approximately 30 mm Hg) reversibly inhibited Kv1.2 and Kv2.1 currents only at potentials more positive than 30 mV. In contrast, hypoxia did not alter Kv1.5 current. Currents generated by coexpression of Kv2.1 with Kv9.3 alpha subunits were reversibly inhibited by hypoxia in the voltage range of the resting membrane potential (E(M)) of PA VSMCs ( approximately 28% at -40 mV). Coexpression of Kv1.2 and Kv1.5 alpha subunits produced currents that displayed kinetic and pharmacological properties distinct from Kv1.2 and Kv1.5 channels expressed alone. Moreover, hypoxia reversibly inhibited Kv1.2/Kv1.5 current activated at physiologically relevant membrane potentials ( approximately 65% at -40 mV). These results indicate that (1) hypoxia reversibly inhibits Kv1.2 and Kv2.1 but not Kv1.5 homomeric channels, (2) Kv1.2 and 1.5 alpha subunits can assemble to form an O(2)-sensitive heteromeric channel, and (3) only Kv1.2/Kv1.5 and Kv2.1/Kv9.3 heteromeric channels are inhibited by hypoxia in the voltage range of the PA VSMC E(M). Thus, these heteromeric channels are strong candidates for the K(+) channel isoforms initiating hypoxic pulmonary vasoconstriction.
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Affiliation(s)
- J T Hulme
- Department of Physiology, Colorado State University, Ft. Collins, CO 80523, USA
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33
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Ferrer-Martínez A, Felipe A, Barceló P, Casado FJ, Ballarín J, Pastor-Anglada M. Lack of effect of clinical doses of cyclosporin A on erythrocyte Na+/K+-ATPase activity. Clin Sci (Lond) 1999; 97:283-90. [PMID: 10464053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Cyclosporin A (CsA) may exert its cytotoxic effects by altering the activity of different plasma membrane transport systems. Although CsA may act at the gene level, it has been also suggested that it can directly alter transport processes at the plasma membrane. To examine this possibility in a physiological context, we determined Na(+)/K(+)-ATPase activity in erythrocytes from two groups of subjects receiving CsA treatment: group I consisted of kidney transplant patients, and group II comprised patients with steroid-resistant idiopathic nephrotic syndrome. Group I patients showed a marked decrease (35%) in the activity of the Na(+)/K(+)-ATPase in erythrocytes immediately after surgery, before the initiation of CsA treatment. The activity remained low 2 days after the introduction of CsA, but had recovered to the original (pre-surgery) value 1 month later. Group II patients showed the same pattern of erythrocyte Na(+)/K(+)-ATPase activity as those in group I. When the blood CsA levels from all patients were plotted against the corresponding erythrocyte Na(+)/K(+)-ATPase transport activity, a significant linear correlation was found. Higher levels of CsA in the blood were correlated significantly with increased Na(+)/K(+)-ATPase activities. The blood sodium concentration was also correlated positively with both erythrocyte Na(+)/K(+)-ATPase activity and blood CsA concentration. Thus CsA treatment is not associated with inhibition of the Na(+)/K(+)-ATPase in erythrocytes.
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Affiliation(s)
- A Ferrer-Martínez
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain
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34
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Abstract
Liver parenchymal cells show a wide variety of plasma membrane transporters that are tightly regulated by endocrine and nutritional factors. This review summarizes work performed in our laboratory on these transport systems, particularly nucleoside transporters, which are up-regulated in physiological situations associated with liver cell growth. Rat hepatocytes show a Na+-dependent nucleoside transport activity that is stimulated by pancreatic hormones. Indeed, this biological activity appears to be the result of the co-expression of at least two isoforms of nucleoside carriers, CNT1 and CNT2 (also called SPNT). These two transporters are up-regulated during the early phase of liver growth after partial hepatectomy, although to different extents, suggesting differential regulation of the two isoforms. The recent generation of isoform-specific antibodies allowed us to demonstrate that carrier expression may also have complex post-transcriptional regulation on the basis of the lack of correspondence between mRNA and protein levels. The analysis of nucleoside transport systems in hepatoma cells and the comparison with those in hepatocytes has also provided evidence that the differentiation status of liver parenchymal cells may determine the pattern of nucleoside transporters expressed.
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Affiliation(s)
- M Pastor-Anglada
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain.
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35
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Abstract
Using histological, histochemical and macroscopic and microscopic measurement techniques, the macroscopic and microscopic structures of coypu ovaries were studied in sexually mature virgin females. The mature ovaries of the coypu were ovoid or elongated bodies, not encapsulated, covered by a single layer of epithelium. They had a parenchyma formed by follicles at different stages of evolution and true and accessory corpora lutea. The interstitial tissue was a prominent and permanent structure in the ovaries. Some ovaries contained a few rete ovarii in the hilus.
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Affiliation(s)
- A Felipe
- Facultad de Ciencias Veterinarias, Universidad Nacional Del Centro de La Provincia de Buenos Aires, Argentina
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36
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del Santo B, Valdés R, Mata J, Felipe A, Casado FJ, Pastor-Anglada M. Differential expression and regulation of nucleoside transport systems in rat liver parenchymal and hepatoma cells. Hepatology 1998; 28:1504-11. [PMID: 9828213 DOI: 10.1002/hep.510280609] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Primary cultures of rat-liver parenchymal cells show carrier-mediated nucleoside uptake by a mechanism that mainly involves concentrative, Na+-dependent transport activity. In contrast, the hepatoma cell line FAO shows high nucleoside transport activity, although it is mostly accounted for by Na+-independent transport processes. This is associated with a low amount of sodium purine nucleoside transporter (SPNT) mRNA. SPNT encodes a purine-preferring transporter expressed in liver parenchymal cells. To analyze whether SPNT expression is modulated during cell proliferation, SPNT mRNA levels were determined in the early phase of liver growth after partial hepatectomy and in synchronized FAO cells that had been induced to proliferate. SPNT mRNA amounts increased as early as 2 hours after partial hepatectomy. FAO cells induced to proliferate after serum refeeding show an increase in SPNT mRNA levels, which is followed by an increase in Na+-dependent nucleoside uptake and occurs before the peak of 3H-thymidine incorporation into DNA. FAO cells also express significant equilibrative nucleoside transport activity, which may be accounted for by the expression of the nitrobenzylthioinosine (NBTI)-sensitive and -insensitive isoforms, rat equilibrative nucleoside transporter 1 (rENT1) and rENT2, respectively. Interestingly, rENT2 mRNA levels follow a similar pattern to that described for SPNT when FAO cells are induced to proliferate, whereas rENT1 appears to be constitutively expressed. Liver parenchymal cells show low and negligible mRNA levels for rENT1 and rENT2 transporters, respectively, although most of the equilibrative transport activity found in hepatocytes is NBTI-resistant. It is concluded that: 1) SPNT expression is regulated both in vivo and in vitro in a way that appears to be dependent on cell cycle progression; 2) SPNT expression may be a feature of differentiated hepatocytes; and 3) equilibrative transporters are differentially regulated, rENT2 expression being cell cycle-dependent. This is consistent with its putative role as a growth factor-induced delayed early response gene.
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Affiliation(s)
- B del Santo
- Departament de Bioquímica i Biologia Molecular Universitat de Barcelona, Spain
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37
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Soler C, Felipe A, Mata JF, Casado FJ, Celada A, Pastor-Anglada M. Regulation of nucleoside transport by lipopolysaccharide, phorbol esters, and tumor necrosis factor-alpha in human B-lymphocytes. J Biol Chem 1998; 273:26939-45. [PMID: 9756942 DOI: 10.1074/jbc.273.41.26939] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nucleoside transport systems and their regulation in human B-lymphocytes have been characterized using the cell lines Raji and Bare lymphoma syndrome-1 (BLS-1) as experimental models. These cells express at least three different nucleoside transport systems as follows: a nitrobenzylthioinosine-sensitive equilibrative transport system of the es-type, which appears to be associated with hENT1 expression, and two Na+-dependent transport systems that may correspond to N1 and to the recently characterized N5-type, which is nitrobenzylthioinosine-sensitive and guanosine-preferring. B cell activators such as phorbol 12-myristate 13-acetate and lipopolysaccharide (LPS) up-regulate both concentrative transport systems but down-regulate the equilibrative es-type transporter, which correlates with lower hENT1 mRNA levels. These effects are dependent on protein kinase C activity. Phorbol 12-myristate 13-acetate and LPS also induce an increase in tumor necrosis factor-alpha (TNF-alpha) mRNA levels, which suggest that this cytokine may mediate some of the effects triggered by these agents, since addition of TNF-alpha alone can increase N1 and N5 transport activities by a mechanism that also depends on protein kinase C activation. Interestingly, TNF-alpha down-regulates es activity, but this effect cannot be abolished by inhibiting protein kinase C. This study reveals differential regulation of nucleoside transport systems following activation of human B-lymphocyte cell lines by agents of physiological relevance such as TNF-alpha and LPS. Moreover, it indicates that the recently characterized N5 transport system can also be regulated following B cell activation, which may be relevant to lymphocyte physiology and to the treatment of lymphocyte malignancies.
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Affiliation(s)
- C Soler
- Departament de Fisiologia (Immunologia) and Fundació Pi i Sunyer, Campus de Bellvitge, Universitat de Barcelona, Diagonal 645, 08071 Barcelona, Spain
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38
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Abstract
Nucleoside analogues used in cancer and anti-viral therapies interfere with nucleotide metabolism and DNA replication, thus inducing their pharmacological effects. A long-awaited goal in the understanding of the pharmacological properties of these molecules, that is the molecular characterization of nucleoside plasma-membrane transporters, has been achieved very recently. These carrier proteins are encoded by at least two gene families and new isoforms remain to be identified. Direct demonstration of translocation of these drugs by nucleoside transporters has already been provided and most of them can inhibit natural nucleoside transport, probably in a competitive manner. The expression of these genes is clearly tissue-specific and might depend on the differentiated status of a cell. This is relevant because the sensitivity of a cell to a drug can depend on the type of nucleoside carrier expressed, and the drug itself might modulate nucleoside carrier expression. In this article, Marçal Pastor-Anglada, Antonio Felipe and Javier Casado discuss recent studies on the regulation of nucleoside carrier expression and of the molecular determinants of substrate specificity. Better knowledge of these will contribute to an improved design of therapies based on nucleoside derivatives.
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Affiliation(s)
- M Pastor-Anglada
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain
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39
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Felipe A, Callejas S, Cabodevila J. Anatomicohistological characteristics of female genital tubular organs of the South American nutria (Myocastor coypus). Anat Histol Embryol 1998; 27:245-50. [PMID: 9741147 DOI: 10.1111/j.1439-0264.1998.tb00188.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Morphohistological features of the tubular organs of the Myocastor coypus (coypu) female reproductive tract were studied. Specimens came from breeding farms with yard breeding systems. The analysis of the organs was made by histological methods and by macro and microscopic measurement techniques. The animals showed oviducts with macro and microscopically differentiable regions. Their inucosa showed primary branched folds in the ampullar sector. In the rest of the oviduct tract these folds were only of the primary type. The double uterus showed regional variations in the lumen, endometrial glands along the whole surface and a wide fibromuscular cervix with pseudoglands. The endocervical mucosa made clear a complex system of folds covered by a mucus-secreting epithelium. In the long vagina of the coypu a folded, rugose and irregular mucosa was observed.
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Affiliation(s)
- A Felipe
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires, Argentina
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40
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Felipe A, Valdes R, Santo B, Lloberas J, Casado J, Pastor-Anglada M. Na+-dependent nucleoside transport in liver: two different isoforms from the same gene family are expressed in liver cells. Biochem J 1998; 330 ( Pt 2):997-1001. [PMID: 9480921 PMCID: PMC1219236 DOI: 10.1042/bj3300997] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatocytes show a Na+-dependent nucleoside transport activity that is kinetically heterogeneous and consistent with the expression of at least two independent concentrative Na+-coupled nucleoside transport systems (Mercader et al. Biochem. J. 317, 835-842, 1996). So far, only a single nucleoside carrier-related cDNA (SPNT) has been isolated from liver cells (Che et al. J. Biol. Chem. 270, 13596-13599, 1995). This cDNA presumably encodes a plasma membrane protein responsible for Na+-dependent purine nucleoside transport activity. Thus, the liver must express, at least, a second nucleoside transporter which should be pyrimidine-preferring. Homology cloning using RT-PCR revealed that a second isoform is indeed present in liver. This second isoform turned out to be identical to the 'epithelial-specific isoform' called cNT1, which shows in fact high specificity for pyrimidine nucleosides. Although cNT1 mRNA is present at lower amounts than SPNT mRNA, the amounts of cNT1 protein, when measured using isoform-specific polyclonal antibodies, were even higher than the SPNT protein levels. Moreover, partially purified basolateral plasma membrane vesicles from liver were enriched in the SPNT but not in the cNT1 protein, which suggests that the subcellular localization of these carrier proteins is different. SPNT and cNT1 protein amounts in crude membrane extracts from 6 h-regenerating rat livers are higher than in the preparations from sham-operated controls (3.5- and 2-fold, respectively). These results suggest that liver parenchymal cells express at least two different isoforms of concentrative nucleoside carriers, the cNT1 and SPNT proteins, which show differential regulation and subcellular localization.
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Affiliation(s)
- A Felipe
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, 08071 Barcelona, Spain
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41
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Gómez-Angelats M, López-Fontanals M, Felipe A, Casado FJ, Pastor-Anglada M. Cytoskeletal-dependent activation of system A for neutral amino acid transport in osmotically stressed mammalian cells: a role for system A in the intracellular accumulation of osmolytes. J Cell Physiol 1997; 173:343-50. [PMID: 9369947 DOI: 10.1002/(sici)1097-4652(199712)173:3<343::aid-jcp6>3.0.co;2-n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
System A activity for neutral amino acid transport is increased after hypertonic shock in NBL-1 (an epithelial cell line) and CHO-K1 cells (a nonepithelial cell line) by a mechanism which is consistent with the synthesis of a regulatory protein that activates preexisting system A carrier proteins (Ruiz-Montasell et al., 1994, Proc. Natl. Acad. Sci. USA, 91,9569-9573). In this study, we have further investigated this biological response by determining the role of cytoskeletal structures in system A regulation by hypertonic stress. Using inhibitors of the microfilament and microtubule networks, we show that the increase in system A activity after hypertonic treatment requires the integrity of both cytoskeletal structures in NBL-1 cells, although the increase in system A activity triggered by amino acid starvation is completely insensitive to any of these drugs. In contrast, the enhancement of system A activity in osmotically stressed CHO-K1 cells is not sensitive to inhibitors of the microtubule network. In both cell types, the results suggest that the inhibitors block the increase of system A activity. System A transport decreases when CHO-K1 cells return to isotonic conditions by a mechanism that is insensitive to inhibitors of protein and mRNA synthesis. The increase in system A transport activity is also followed by the accumulation of neutral amino acids (fourfold for alanine), which is totally blocked by the same agents (cycloheximide and actinomycin D) that prevent the increase in system A activity after hypertonic treatment, thus indicating that system A is crucial for maintaining a high concentration of organic osmolytes inside the cell.
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Affiliation(s)
- M Gómez-Angelats
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Spain
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Ferrer-Martínez A, Felipe A, Mata JF, Casado FJ, Pastor-Anglada M. Molecular cloning of a bovine renal G-protein coupled receptor gene (bRGR): regulation of bRGR mRNA levels by amino acid availability. Biochem Biophys Res Commun 1997; 238:107-12. [PMID: 9299461 DOI: 10.1006/bbrc.1997.7185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A cDNA of 3.2 kb, encoding a putative G protein-coupled receptor and hence called bRGR1, has been isolated from a cDNA library generated from the bovine renal epithelial cell line NBL-1. This cDNA consisted of 41 base pairs of 5'-untranslated sequence, an open reading frame of 1083 base pairs, and a 2.07 kb fragment of 3'-untranslated sequence that includes a poly(dA) tail. The coding sequence predicts a protein of 361 residues. The ligand of the bRGR1 protein may be of low molecular weight, as deduced from the analysis of the predicted primary structure of the receptor protein and the comparison with other subtypes of the G protein-coupled receptor family. The amounts of bRGR1 mRNA significantly increase when NBL-1 cells are cultured in an amino acid-depleted medium. This effect can not be caused by a decrease in protein synthesis because cycloheximide did not mimic the increase in bRGR1 mRNA levels triggered by amino acid starvation. These data suggest that bRGR1 may be an amino acid-regulated gene.
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Affiliation(s)
- A Ferrer-Martínez
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Spain
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Abstract
In agreement with the principles of the relativistic model proposed by Creutzfeldt et al., with the photometric rule (lightness anchoring rule) and with the influence of simultaneous contrast in the appearance of a visual scene, we propose a first-stage mechanism yielding substantial colour constancy. We have defined a set of first-stage colour descriptors, and to test their utility, we have performed a simulation using a Machine Vision System (MVS). The statistical stability of the descriptors for Munsell samples under different illuminants is good.
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Affiliation(s)
- F Martínez-Verdú
- Dpto. de Optica. Facultad de Física. Universitat de València. Spain
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Felipe A, Artigas JM, Pons AM, Buades MJ. Human contrast sensitivity in coherent Maxwellian view: effect of coherent noise and comparison with speckle. J Opt Soc Am A Opt Image Sci Vis 1997; 14:972-983. [PMID: 9114508 DOI: 10.1364/josaa.14.000972] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Lasers have been used in vision for measuring the neural contrast sensitivity function (CSF) by forming interference fringes on the retina. We distinguish among three kinds of illumination with lasers: incoherent (without noise), Maxwellian or coherent (with coherent noise), and diffuse coherent (with speckle). The three have different characteristics and different CSF's. A coherent imaging system is designed to measure the CSF with fully coherent illumination. This is the CSF of the whole visual system, although it is measured with gratings imaged on the retina. It therefore differs from the neural CSF's measured by other authors with partially coherent illumination. However, the neural CSF's are also obtained in this study with and without noise. The effects of coherent noise and speckle on both the visual system and neural sensitivities are studied and compared. Coherent noise differs from speckle in the following ways: (1) It behaves as a high-pass filter, reducing sensitivity in the low-spatial-frequency range, whereas speckle is a low-pass filter; (2) quantitatively, coherent noise reduces neural sensitivity by a factor k(m) with a maximum value between 4 and 6, whereas speckle reduces neural sensitivity by a factor ks with a maximum value of approximately 25 (1.4 log units) for a 3-mm pupil and up to 35 (1.55 log units) for a 1-mm pupil; (3) the masking effect of the coherent noise is affected by changes in luminance but not by changes in pupil diameter; however, the pupil size is the main parameter affecting the masking effect of the speckle.
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Affiliation(s)
- A Felipe
- Departamento de Optica, Facultat de Fisica, Universitat de Valencia, Spain
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Felipe A, Ferrer-Martínez A, Casado FJ, Pastor-Anglada M. Expression of sodium-dependent purine nucleoside carrier (SPNT) mRNA correlates with nucleoside transport activity in rat liver. Biochem Biophys Res Commun 1997; 233:572-5. [PMID: 9144579 DOI: 10.1006/bbrc.1997.6498] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The expression of sodium-dependent purine nucleoside transport (SPNT) mRNA has been studied in physiological situations in which Na+-dependent nucleoside uptake in plasma membrane vesicles from rat liver was induced. Sodium-dependent uridine transport rates were induced in genetically obese Zucker rats, during liver regeneration after partial hepatectomy, and under euglycemic-hyperinsulinemic clamp. A PCR-generated fragment, based on a published SPNT sequence cloned from rat liver, was used as a probe in Northern blot analysis. We show that the hepatic mRNA levels of the putative sodium-dependent transport system SPNT correlate with the sodium-dependent uridine transport rates in plasma membrane vesicles from rat liver. These results suggest that the induction of the sodium-dependent nucleoside transport expressed in liver parenchymal cells involves regulation of SPNT gene expression.
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Affiliation(s)
- A Felipe
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain
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Castaño E, Marzabal P, Casado FJ, Felipe A, Pastor-Anglada M. Na+,K(+)-ATPase expression in maleic-acid-induced Fanconi syndrome in rats. Clin Sci (Lond) 1997; 92:247-53. [PMID: 9093004 DOI: 10.1042/cs0920247] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Na+,K(+)-ATPase activity and its alpha 1 subunit protein and mRNA in kidney cortex were monitored in rats developing Fanconi syndrome after the administration of maleate. Na+,K(+)-ATPase activity was significantly lower than in saline-injected controls, although this was partially mediated by a general, non-specific decrease in the cortex protein content. 2. The low activity of the sodium pump correlated with low abundance of alpha 1 subunit mRNA and protein levels. Hsp60 protein levels were also decreased in kidney cortex from maleate-treated rats. 3. Kidney cortex brush-border membrane vesicles from maleate-treated rats showed a marked decrease in Na(+)-dependent alanine and glucose transport, which was not dependent on the Na(+)-transmembrane gradient itself, a finding which is consistent with a more stable effect at the plasma membrane level. 4. The effect of maleate may be partially non-specific and involve a great variety of proteins, but seems to be restricted to selected tissues because alpha 1 subunit Na+,K(+)-ATPase and hsp60 protein amounts were not significantly modified in livers from rats developing Fanconi syndrome. 5. These results show that maleate administration induces a low activity of selected concentrative transport systems and a decrease in Na+,K(+)-ATPase activity and expression. The combination of both effects may explain the increased excretion of most organic solutes present in rats developing Fanconi syndrome.
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Affiliation(s)
- E Castaño
- Department de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain
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Pinochet J, Aglès M, Dalmau E, Fernández C, Felipe A. Prunus Rootstock Evaluation to Root-knot and Lesion Nematodes in Spain. J Nematol 1996; 28:616-623. [PMID: 19277184 PMCID: PMC2619732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Two screening and one resistance verification trial involving 20 Prunus rootstocks were conducted under greenhouse conditions against Meloidogyne spp. and Pratylenchus vulnus. Most of the rootstocks were experimental genotypes or new commercial peach and plums of Spanish and French origin. Nearly all are interspecific hybrid rootstocks. In the first trial, the rootstocks Bruce, Cadaman, Mirac, G x N No. 15, Cachirulo x (G x N No. 9), and P. myra x peach were immune or resistant to a mixture of seven isolates of M. incognita. In the second screening trial, the hybrid plum P 2588 was a poor host to a mixture of four isolates of P. vulnus. The remaining seven rootstocks were good hosts to the root-lesion nematode. In the resistance verification trial GF-31, G x N No. 15, Torinel, AD- l 01, Monpol, Nemaguard, and Cadaman maintained a high level of resistance when tested against a mixture of 17 isolates comprising M. incognita, M. javanica, M. arenaria, M. hapla, and M. hispanica. Barrier peach suffered a partial loss of resistance not detected in previous tests.
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Ferrer-Martínez A, Felipe A, Barceló P, Casado FJ, Ballarín J, Pastor-Anglada M. Effects of cyclosporine A on Na,K-ATPase expression in the renal epithelial cell line NBL-1. Kidney Int 1996; 50:1483-9. [PMID: 8914013 DOI: 10.1038/ki.1996.462] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The bovine renal epithelial cell line NBL-1 has been used to monitor the effects of cyclosporine A (CsA) on Na+,K(+)-ATPase activity and expression. CsA at two single doses (0.6 mg/liter and 2.5 mg/liter) inhibits the ouabain-sensitive component of Rb+ uptake, assumed to be Na+,K(+)-ATPase, but increases the low activity of a furosemide-sensitive component corresponding to a Na+/K+/Cl- cotransporter. CsA addition also induces a slight decrease of alpha 1 subunit mRNA levels, without altering the already low beta 1 subunit mRNA amounts. Hypertonic treatment of NBL-1 cells leads to a significant increase in both Na+,K(+)-ATPase activity and alpha 1 subunit mRNA amounts, but does not modify beta 1 subunit mRNA levels. The differential response of the alpha 1 and beta 1 subunit genes may explain why hypertonic treatment does not result in higher alpha 1 protein expression, and supports the view that increased activity relies upon post-translational events, despite the likely transcriptional activation of the alpha 1 subunit gene. The addition of CsA does not alter the hypertonicity-mediated increase of Na+,K(+)-ATPase activity but blocks the accumulation of alpha 1 subunit mRNA. In conclusion, CsA may compromise the ion handling by renal cells as a result of the inhibition of basal Na+,K(+)-ATPase activity and the stimulation of Na+/K+/Cl- cotransport activity. Moreover, this is the first report showing that CsA may affect the long-term adaptation of the pump by altering its subunit gene expression.
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Affiliation(s)
- A Ferrer-Martínez
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain
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Abstract
Expression of Na(+)-K(+)-adenosinetriphosphatase (ATPase) in tissues from obese and lean Zucker rats was monitored. The phosphatase activity of the sodium pump was increased in liver and intestinal mucosa from obese animals but was unaltered in skeletal muscle, brown adipose tissue, kidney, and heart. Induction of Na(+)-K(+)-ATPase activity was correlated with increased alpha 1-subunit protein amounts in liver and intestinal mucosa, although alpha 1-subunit mRNA levels were increased only in liver tissue. Neither protein nor mRNA amounts for both subunits were significantly altered in the other tissues analyzed. The only exception was a decrease in the amount of beta 1-protein in kidney from obese rats. alpha 2-Subunit protein and alpha 2- and beta 2-mRNA levels were not altered in brown adipose tissue, heart, and soleus. In summary, this study shows that in obese Zucker rats the expression of the sodium pump is enhanced in tissues that are directly involved in nutrient uptake and processing. This adaptation may be related to the ongoing hyperphagia and to tissue hypertrophia but develops in a different manner in each tissue, suggesting differential regulation of alpha 1-subunit expression.
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Affiliation(s)
- A Ferrer-Martínez
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Spain
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