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1.
Int Rev Psychiatry ; 34(5): 530-533, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-36165758

RESUMEN

A growing body of research shows the inimical impact of climate change on people's mental health. However, attention to mental health providers at the frontlines is rather sparse, especially in climate-vulnerable countries. This commentary aims to present the perspectives and experiences of mental health providers within the context of climate change in the Philippines. Specifically, this paper explicates the challenges faced by mental health providers in trying to address the increasing climate-related distress experienced by many Filipinos and the recent progress in promoting climate change and mental health nexus in the country. The recommendations offered in this commentary will hopefully provide the basis for a more comprehensive mental health framework that incorporates climate change and supports mental health providers in their pursuit to preserve Filipino mental health on a warming planet.


Asunto(s)
Salud Mental , Planetas , Cambio Climático , Humanos , Filipinas
2.
J Electr Eng Technol ; 17(6): 3581-3592, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37520431

RESUMEN

An examination of the human gait is feasible using inertial sensing. The embedded accelerometer and gyroscope in an inertial measurement unit can evaluate physical activity-based sports and this unit is relatively affordable compared to global positioning systems or video recording quantification. This study developed a cost-effective sports monitoring investigation method with an inertial sensor attached to the right leg of the athletes. In total, four parameters were simultaneously tracked to assess the entire sensor performance in real-time. The accelerometer measured the typical leg angle when walking and running, whereas the gyroscope processed the raw data to obtain the stride frequency from the time-domain data. Moreover, a comparison between the accelerometer and gyroscope was presented while simultaneously attaining the signal to convert the time-domain data to frequency results. Also, the number of strides and linear velocity was expressed as results in this study. To confirm the results, a statistical hypothesis test was implemented for all obtained results. The results indicated that the inertial sensing instrumentation used in this study is promising and could be an affordable alternative option for a sports monitoring system.

4.
J Phys Condens Matter ; 33(9): 095503, 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33232944

RESUMEN

The time evolution of a low-energy two-dimensional Gaussian wave packet in ABC-stacked n-layer graphene (ABC-NLG) is investigated. Expectation values of the position (x, y) of center-of-mass and the total probability densities of the wave packet are calculated analytically using the Green's function method. These results are confirmed using an alternative numerical method based on the split-operator technique within the Dirac approach for ABC-NLG, which additionally allows to include external fields and potentials. The main features of the zitterbewegung (trembling motion) of wave packets in graphene are demonstrated and are found to depend not only on the wave packet width and initial pseudospin polarization, but also on the number of layers. Moreover, the analytical and numerical methods proposed here allow to investigate wave packet dynamics in graphene systems with an arbitrary number of layers and arbitrary potential landscapes.

5.
Ambio ; 47(4): 410-426, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29168121

RESUMEN

Contribution of fisheries and aquaculture to global food security is linked to increased fish consumption. Projections indicate that an additional 30-40 million tonnes of fish will be required by 2030. China leads global aquaculture production accounting for 60% in volume and 45% in value. Many changes in the Chinese aquaculture sector are occurring to strive towards attaining environmental integrity and prudent use of resources. We focus on changes introduced in freshwater aquaculture developments in China, the main source of food fish supplies. We bring forth evidence in support of the contention that Chinese freshwater aquaculture sector has introduced major paradigm changes such as prohibition of fertilisation in large water bodies, introduction of stringent standards on nutrients in effluent and encouragement of practices that strip nutrients among others, which will facilitate long-term sustainability of the sector.


Asunto(s)
Acuicultura , Explotaciones Pesqueras , Abastecimiento de Alimentos , Animales , China , Peces , Agua Dulce
6.
Diabetes Metab ; 44(1): 55-60, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28916390

RESUMEN

AIM: Kidney hypoxia can predispose to the development of acute and chronic renal failure in diabetes. Ischaemia-reperfusion injury (IRI) causes inflammation, and diabetes is known to exacerbate this inflammatory response in the kidney, whereas alarmin IL-33 could act as an innate immune mediator during kidney IRI. Thus, the present study examined the impact of genetic IL-33 receptor ST2 deficiency (ST2-/-) on renal IRI in euglycaemic and hyperglycaemic mice. METHODS: Hyperglycaemia was induced with streptozotocin (STZ) in adult male C57BL/6JRj wild-type (WT) mice and ST2-/- mice. Unilateral renal IRI was achieved 3months after STZ treatment by left kidney nephrectomy (non-ischaemic control kidney) and clamping of the right renal artery for 32min in STZ- and vehicle-treated animals. At 24h after reperfusion, renal function and injury were determined by levels of plasma creatinine, blood urea nitrogen (BUN) and histological tubule scores. Also, in a complementary pilot clinical study, soluble ST2 concentrations were compared in diabetics and non-diabetics. RESULTS: Urinary albumin was significantly increased in STZ-induced hyperglycaemic mice, regardless of genotypic background. At 24h post-ischaemia, plasma creatinine, BUN and tubular injury were significantly reduced in ST2-/- mice compared with vehicle-treated WT mice, but this protective effect was lost in the STZ-induced hyperglycaemic ST2-/- animals. Plasma concentrations of soluble ST2 were significantly greater in type 2 diabetes patients vs non-diabetics. CONCLUSION: Our data suggest that the IL-33/ST2 pathway exerts differential effects depending on the glucose environment, opening-up new avenues for future research on alarmins and diabetes in ischaemia-related diseases.


Asunto(s)
Lesión Renal Aguda/metabolismo , Glucemia/metabolismo , Hiperglucemia/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/genética , Daño por Reperfusión/metabolismo , Anciano , Animales , Diabetes Mellitus Experimental , Femenino , Humanos , Hiperglucemia/inducido químicamente , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Riñón/metabolismo , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Estreptozocina/efectos adversos
7.
Nat Prod Commun ; 11(10): 1523-1526, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30549613

RESUMEN

The anti-inflammatory activity of the essential oils from Seseli corymbosum subsp. coiymbosum Pall. ex Sm. (SC) and Seseli gummiferum Boiss. & Heldr. subsp. corymbosum (SG) was investigated for the first time on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The main constituents (determined by GC-FID and GC-MS analyses) were germacrene D (54.1%) and sabinene (22.4%) in SG oil and ß-phellandrene (29.2%), α-phellandrene (8.2%) and germacrene D (2.5%) in SC oil. SC and SG oils inhibited nitric oxide (NO) production with IC50 values of 56.1 and 108.2 µg/mL, respectively. The oils also inhibited prostaglandin E2 (PGE2) with IC50 values of 49.4 µg/mL (SC oil) and 95.5 µg/mL (SG oil). The inhibitory effect of SC and SG oils was accompanied by dose-dependent decreases of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expressions in LPS-induced RAW 264.7 cells. The research of the reporter gene assay on nuclear factor KB (NF-KB) showed that SC and SG oils inhibited NF-KB transcriptional activity. The obtained results suggest that SC and SG oils exert the anti-inflammatory effects in LPS-stimulated RAW 264.7 cells by suppressing NF-KB activation.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Apiaceae/química , Aceites Volátiles/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Inhibidores de la Ciclooxigenasa 2/farmacología , Dinoprostona/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Genes Reporteros/efectos de los fármacos , Lipopolisacáridos/farmacología , Ratones , FN-kappa B/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Aceites Volátiles/química , Células RAW 264.7
8.
Ambio ; 45(3): 361-73, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26508174

RESUMEN

Results of a survey of 156 Chinese mitten crab (Eriocheir sinensis) grow-out farms around Hongze Lake (118.48-118.72°E; 33.36-33.38°N) are reported. Area farmed has remained relatively unchanged but production (59 932 t in 2012) increased steadily over the last 7 years, indicative of the viability and sustainability of the farming system that has gradually replaced intensive Chinese major carp polyculture around Hongze Lake. Results showed that production range was 135-2400 kg ha(-1) cycle(-1) (mean 1144 ± 34). Crab yields correlated linearly to stocking density and conformed to a normal distribution curve, with 66.7 % of farms yielding 900 kg ha(-1) cycle(-1) or more. Yield was negatively correlated to pond size and capture size (p < 0.01), and farms with macrophyte coverage rate lower than 30 % of water surface were significantly (p < 0.05) lower than those exceeding 30 %.


Asunto(s)
Acuicultura/métodos , Braquiuros , Conservación de los Recursos Naturales , Animales , Acuicultura/economía , China , Análisis Costo-Beneficio , Dieta , Lagos , Plantas , Calidad del Agua , Abastecimiento de Agua
9.
Springerplus ; 4: 46, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25674502

RESUMEN

This study investigated the perceptions on and adaptations to climate change impacts of 235 pangasius farmers in the Mekong Delta, Vietnam. Data were collected using semi-structured household surveys in six provinces, from three regions along the Mekong river branches. A Chi-Square test was used to determine the association between variables, and a logit regression model was employed to identify factors correlated with farmer's perception and adaptation. Less than half of respondents were concerned about climate change and sought suitable adaptation measures to alleviate its impacts. Improving information on climate change and introducing early warning systems could improve the adaptive capacity of pangasius farmers, in particularly for those farmers, who were not concerned yet. Farmers relied strongly on technical support from government agencies, but farmers in the coastal provinces did not express the need for training by these institutions. This contrasting result requires further assessment of the effectiveness of adaptation measures such as breeding salinity tolerant pangasius.

10.
Ambio ; 43(8): 1059-68, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24715387

RESUMEN

In Vietnam, culturing striped catfish makes an important contribution to the Mekong Delta's economy. Water level rise during rainy season and salt intrusion during dry season affect the water exchange and quality for this culture. Sea level rise as a consequence of climate change will worsen these influences. In this study, water level rise and salt water intrusion for three sea level rise (SLR) scenarios (i.e., +30, +50, and +75 cm) were simulated. The results showed that at SLR +50, the 3-m-flood level would spread downstream and threaten farms located in AnGiang, DongThap and CanTho provinces. Rising salinity levels for SLR +75 would reduce the window appropriate for the culture in SocTrang and BenTre provinces, and in TienGiang's coastal districts. Next to increasing dikes to reduce the impacts, the most tenable and least disruptive option to the farming community would be to shift to a salinity tolerant strain of catfish.


Asunto(s)
Acuicultura , Bagres , Cambio Climático , Animales , Salinidad , Vietnam
11.
J Phys Condens Matter ; 24(37): 375301, 2012 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-22890024

RESUMEN

A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown.

12.
Ambio ; 39(7): 504-14, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21090005

RESUMEN

In this study an attempt is made to estimate nitrogen and phosphorus discharged to the environment from the striped catfish (Pangasianodon hypophthalmus) farming sector in the Mekong Delta (8 degrees 33'-10 degrees 55' N, 104 degrees 30'-106 degrees 50' E), South Vietnam. The sector accounted for 687,000 t production in 2007 and 1,094,879 t in 2008, with over 95% of the produce destined for export to over 100 countries. Commercial and farm-made feeds are used in catfish farming, currently the former being more predominant. Nitrogen discharge levels were similar for commercial feeds (median 46.0 kg/t fish) and farm-made feeds (median 46.8 kg/t fish); whilst, phosphorus discharge levels for commercial feeds (median 14.4 kg/t fish) were considerably lower than for farm-made feeds (median 18.4 kg/t fish). Based on the median nutrient discharge levels for commercial feeds, striped catfish production in the Mekong Delta discharged 31,602 t N and 9,893 t P, and 50,364 t N and 15,766 t P in 2007 and 2008, respectively. However, the amount of nutrients returned directly to the Mekong River may be substantially less than this as a significant proportion of the water used for catfish farming as well as the sludge is diverted to other agricultural farming systems. Striped catfish farming in the Mekong Delta compared favourably with other cultured species, irrespective of the type of feed used, when the total amounts of N and P discharged in the production of a tonne of production was estimated.


Asunto(s)
Acuicultura , Bagres , Nitrógeno/análisis , Fósforo/análisis , Contaminación del Agua/análisis , Animales , Ríos , Vietnam
13.
J Phys Condens Matter ; 22(46): 465305, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-21403366

RESUMEN

In this work we investigate the interaction of charge carriers in graphene with a series of p-n-p junctions arranged according to a deterministic quasiperiodic substitutional Fibonacci sequence. The junctions create a potential landscape with quantum wells and barriers of different widths, allowing the existence of quasi-confined states. Spectra of quasi-confined states are calculated for several generations of the Fibonacci sequence as a function of the wavevector component parallel to the barrier interfaces. The results show that, as the Fibonacci generation is increased, the dispersion branches form energy bands distributed as a Cantor-like set. Besides, for a quasiperiodic set of potential barriers, we obtain the electronic tunneling probability as a function of energy, which shows a striking self-similar behavior for different generation numbers.

14.
Ambio ; 38(1): 24-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19260343

RESUMEN

Aquaculture is seen as an alternative to meeting the widening gap in global rising demand and decreasing supply for aquatic food products. Asia, the epicenter of the global aquaculture industry, accounts for over 90% of the global aquaculture production quantity and about 80% of the value. Asian aquaculture, as with global aquaculture, is dependent to a significant extent on alien species, as is the case for all the major food crops and husbanded terrestrial animals. However, voluntary and or accidental introduction of exotic aquatic species (alien species) is known to negatively impact local biodiversity. In this relatively young food production industry, mitigating the dependence on alien species, and thereby minimizing potential negative impacts on biodiversity, is an imperative for a sustainable future. In this context an attempt is made in this synthesis to understand such phenomena, especially with reference to Asian inland finfish, the mainstay of global aquaculture production. It is pointed out that there is potential for aquaculture, which is becoming an increasingly important food production process, not to follow the past path of terrestrial food crops and husbanded animals in regard to their negative influences on biodiversity.


Asunto(s)
Acuicultura/métodos , Biodiversidad , Peces/fisiología , Animales , Asia , Conservación de los Recursos Naturales , Agua Dulce , Dinámica Poblacional
15.
J Agric Food Chem ; 56(19): 9037-45, 2008 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-18783236

RESUMEN

The aim of this study was to determine the effects of starvation and water quality during the purging process on the biometric parameters, fatty acids, and flavor volatiles of Murray cod farmed in a recirculation system. Market size Murray cod, at the end of the grow-out stage, were divided into eight treatments. The treatments were either fed/starved (F or S) and kept in clean water (CW: CWF2, CWS2, CWF4, and CWS4) or fed/starved and kept in recycled water (RW: RWF2, RWS2, RWF4, and RWS4) for either 2 or 4 weeks. Fish were sampled at 0, 2, and 4 week intervals. Food deprivation was responsible for a significant (P < 0.05) weight loss compared to that of fed treatments. The same was observed for the condition factor (K), hepatosomatic index (HSI), and dress-out percentage (DP). No significant changes were, however, observed in the visceral fat index (VFI). Saturated fatty acids (SFA) were highest in RWF4 and lowest in CWS4 (P < 0.05), while monounsaturated fatty acids (MUFA) were lowest in CWF4 (P < 0.05). Starvation did not affect the flavor volatile compounds, which were mainly affected by changes in water quality. Specifically, total aldehyde (% w/w) content was significantly (P < 0.05) affected by water quality, but the time of purging was not responsible for any noteworthy differences. This study was able to separate the effects of starvation and water quality, in the purging process, on the final eating quality of farmed market size Murray cod. It is concluded that because of the inevitable weight loss during starvation, Murray cod should be fed during the purging stage but kept in clean water and deprived of food only for the time necessary to empty the gastro-intestinal tract.


Asunto(s)
Acuicultura/métodos , Privación de Alimentos , Gadiformes/crecimiento & desarrollo , Agua/química , Animales , Ácidos Grasos/análisis , Tracto Gastrointestinal , Lípidos/análisis , Carne/análisis , Gusto
16.
Lipids ; 42(11): 1065-71, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17701238

RESUMEN

Currently there are several contrasting methods utilized for estimating elongation and desaturation of fatty acids and their general metabolism. The majority of these methods involve an ex vivo approach, requiring expensive and sophisticated equipment, likely to result in considerable variation in enzyme activity between and within species. In the present paper we introduce a further development of the whole-body fatty acid balance method for the estimation of the elongation and desaturation of fatty acids. This method though receiving considerable attention because of its simplicity and reliability has yet to be presented in detail. Theoretically, the whole-body fatty acid balance method can potentially be applied to any organism and requires little more than a gas chromatography unit for fatty acid analysis and elementary calculations. As such in this paper we attempt to spell out in detail the theoretical basis and the methods of application drawing specific examples. Using the present method it is possible to measure the fate of individual fatty acids towards desaturation, elongation and oxidation and calculate the elongase, Delta-6 desaturase and Delta-5 desaturase activities.


Asunto(s)
Ácidos Grasos Insaturados/metabolismo , Ácidos Grasos/metabolismo , Acetiltransferasas/metabolismo , Animales , delta-5 Desaturasa de Ácido Graso , Dieta , Ácido Graso Desaturasas/metabolismo , Elongasas de Ácidos Grasos , Ácidos Grasos/análisis , Homeostasis , Linoleoil-CoA Desaturasa/metabolismo , Oxidación-Reducción , Oxidorreductasas/metabolismo
17.
J Agric Food Chem ; 55(4): 1582-91, 2007 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-17243697

RESUMEN

The aim of the present investigation was to quantify the fate of C18 and long chain polyunsaturated dietary fatty acids in the freshwater fish, Murray cod, using the in vivo, whole-body fatty acid balance method. Juvenile Murray cod were fed one of five iso-nitrogenous, iso-energetic, semipurified experimental diets in which the dietary fish oil (FO) was replaced (0, 25, 50, 75, and 100%) with a blended vegetable oil (VO), specifically formulated to match the major fatty acid classes [saturated fatty acids, monounsaturated fatty acids, n-3 polyunsaturated fatty acids (PUFA), and n-6 PUFA] of cod liver oil (FO). However, the PUFA fraction of the VO was dominated by C18 fatty acids, while C20/22 fatty acids were prevalent in the FO PUFA fraction. Generally, there was a clear reflection of the dietary fatty acid composition across each of the five treatments in the carcass, fillet, and liver. Lipid metabolism was affected by the modification of the dietary lipid source. The desaturation and elongation of C18 PUFAs increased with vegetable oil substitution, supported by the occurrence of longer and higher desaturated homologous fatty acids. However, increased elongase and desaturase activity is unlikely to fulfill the gap observed in fatty acid composition resulting from decreased highly unsaturated fatty acids intake.


Asunto(s)
Grasas de la Dieta/farmacología , Ácidos Grasos/metabolismo , Perciformes/metabolismo , Acetiltransferasas/metabolismo , Animales , Elongasas de Ácidos Grasos , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/administración & dosificación , Aceites de Pescado/administración & dosificación , Linoleoil-CoA Desaturasa/metabolismo , Aceites de Plantas/administración & dosificación
18.
Artículo en Inglés | MEDLINE | ID: mdl-16513379

RESUMEN

The whole-body fatty acid balance method was used to investigate the fatty acid metabolism in Murray cod (Maccullochella peelii peelii) fed diets containing canola (CO) or linseed oil (LO). Murray cod were able to elongate and desaturate both 18:2n-6 and 18:3n-3. In fish fed the CO diet, 54.4% of the 18:2n-6 consumed was accumulated, 38.5% oxidized and 6.4% elongated and desaturated to higher homologs. Fish fed the LO diet accumulated 52.9%, oxidized 37% and elongated and desaturated 8.6% of the consumed 18:3n-3. The overall roles of n-6 fatty acids appeared more important in Murray cod compared to other freshwater species. Murray cod also showed a preferential order of utilization of C18 fatty acid for energy production (18:3n-3 > 18:2n-6 > 18:1n-9). Moreover, it is demonstrated that an increase in dietary 18:3n-3 is directly responsible of increased desaturase activity and augmented saturated fatty acid accumulation in the fish body. The present study also suggests that, in the context of the possible maximization of the natural ability of fish to produce long chain polyunsaturated fatty acids, the whole-body approach can be considered well suited and informative and Murray cod is a suited candidate to fish oil replacement for its diets.


Asunto(s)
Grasas de la Dieta/farmacología , Ácidos Grasos Insaturados/metabolismo , Ácidos Grasos/metabolismo , Perciformes/metabolismo , Animales , Grasas de la Dieta/administración & dosificación , Metabolismo Energético , Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Insaturados/análisis , Ácido Linoleico/metabolismo , Linoleoil-CoA Desaturasa/metabolismo , Aceite de Linaza/administración & dosificación , Ácido Oléico/metabolismo , Aceite de Brassica napus
19.
Peptides ; 26(9): 1567-72, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16112394

RESUMEN

The media of the rat hepatic portal vein is composed of an internal circular muscular layer (CL) and an external longitudinal muscular layer (LL). These two perpendicular layers differentiate progressively from mesenchymal cells within the first month after birth. In this paper, we studied the development of calcitonin gene-related peptide (CGRP) innervation during post-natal differentiation of the vessel. We show that CGRP innervation is already present around the vessel at birth in the future adventitia but far from the lumen of the vessel. Progressively, CGRP immunoreactive fibers reached first LL then CL. CL by itself become only innervated at day 14 after birth. This corresponds to the time at which thick filaments (myosin) are visible in electron microscopy and desmin visualisable by immunocytochemistry. Furthermore, we provide evidence by autoradiography, that binding sites for CGRP are transiently expressed on the portal vein media at day 1 and 14 after birth. Vascular smooth muscle cells were transfected with constructs containing promoters for desmin or smooth muscle myosin heavy chain (smMHC). CGRP treatment of the cells significantly increased the expression of smMHC. Overall these results suggest that CGRP can potentially influence the differentiation of smooth muscle cells from the vessel wall.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/fisiología , Diferenciación Celular/fisiología , Músculo Liso Vascular/crecimiento & desarrollo , Miocitos del Músculo Liso/fisiología , Vena Porta/crecimiento & desarrollo , Factores de Edad , Animales , Sitios de Unión , Péptido Relacionado con Gen de Calcitonina/análisis , Péptido Relacionado con Gen de Calcitonina/farmacología , Línea Celular , Tejido Conectivo/inervación , Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Hígado/irrigación sanguínea , Luciferasas/genética , Luciferasas/metabolismo , Ratones , Músculo Liso Vascular/inervación , Miocitos del Músculo Liso/efectos de los fármacos , Cadenas Pesadas de Miosina/genética , Neuropéptidos/farmacología , Neuropéptidos/fisiología , Vena Porta/química , Vena Porta/inervación , Regiones Promotoras Genéticas/genética , Conejos , Ratas , Ratas Wistar , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transfección
20.
Circ Res ; 93(7): 674-81, 2003 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-12970113

RESUMEN

Osteopontin (OPN), an RGD-containing extracellular matrix protein, is associated with arterial smooth muscle cell (SMC) activation in vitro and in vivo. Many cytokines and growth factors involved in vessel wall remodeling induce OPN overexpression. Moreover, we recently demonstrated that the extracellular nucleotide UTP also induces OPN expression and that OPN is essential for UTP-mediated SMC migration. Thus, we set out to investigate the mechanisms of OPN expression. The aim of this study was to identify transcription factors involved in the regulation of OPN expression in SMCs. First, we explored the contribution of mRNA stabilization and transcription in the increase of UTP-induced OPN mRNA levels. We show that UTP induced OPN mRNA increases via both OPN mRNA stabilization and OPN promoter activation. Then, to identify transcription factors involved in UTP-induced OPN transcription, we located a promoter element activated by UTP within the rat OPN promoter using a gene reporter assay strategy. The -96 to +1 region mediated UTP-induced OPN overexpression (+276+/-60%). Sequence analysis of this region revealed a potential site for AP-1 located at -76. When this AP-1 site was deleted, UTP-induced activation of the -96 to +1 region was totally inhibited. Thus, this AP-1 (-76) site is involved in UTP-induced OPN transcription. A supershift assay revealed that both c-Fos and c-Jun bind to this AP-1 site. Finally, we demonstrate that angiotensin II and platelet-derived growth factor, two main factors involved in vessel wall pathology, also modulated OPN expression via AP-1 activation.


Asunto(s)
Músculo Liso Vascular/efectos de los fármacos , Sialoglicoproteínas/genética , Factor de Transcripción AP-1/metabolismo , Uridina Trifosfato/farmacología , Angiotensina II/farmacología , Animales , Aorta Torácica/citología , Sitios de Unión/genética , Northern Blotting , Células Cultivadas , Ensayo de Cambio de Movilidad Electroforética , Regulación de la Expresión Génica/efectos de los fármacos , Luciferasas/genética , Luciferasas/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Osteopontina , Factor de Crecimiento Derivado de Plaquetas/farmacología , Regiones Promotoras Genéticas/genética , Unión Proteica , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Estabilidad del ARN/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos/genética , Factores de Tiempo , Transcripción Genética/efectos de los fármacos
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