RESUMEN
The behavior, growth and development, and production performance of poultry are affected by the light environment. The influence of light results from a combination of light sources, light intensity, light color, and the photoperiod regimen. With light-emitting diode (LED) lamps applied in poultry housing systems, specific light colors are desired for each time period for layer chickens. The objective of this study was to investigate the effects of a 2-phase mixed color lighting program (phase 1: blue-green, 1 D-13 wk; phase 2: yellow-orange, 14-20 wk) using LED lights on the blood parameters, skeletal development parameters, and sexual development parameters of caged layer chickens during their brooding and rearing periods. Fifty-two chickens were raised from 1 D to 20 wk of age in each of the 4 treatment groups with 3 replicates, with white (400-700 nm) light at phase 1 and phase 2 (WL treatment as the control); blue-green (435-565 nm) light at phase 1 followed by yellow-orange (565-630 nm) light at phase 2 (BG-YOL treatment); yellow-orange LED (565-630 nm) light at phase 1 and phase 2 (YOL treatment); and blue-green (435-565 nm) light at phase 1 and phase 2 (BGL treatment). The results showed that the serum Ig concentrations of the layer chickens in the BG-YOL treatment and BGL treatment were higher than those in the WL treatment at 13 wk of age (P < 0.05). At the age of 20 wk, the serum glucose concentration levels of the pullets after the WL and BGL treatments were lower than those after the YOL treatment (P < 0.05). Compared with the WL treatment, the YOL treatment significantly increased the bone mineral density of the layer chickens (P < 0.05), and BG-YOL treatment promoted the development of the sexual organs (oviducts and ovaries) of the laying hens at the age of 20 wk (P < 0.05). For the 50% egg production age, the YOL treatment was earlier than the other 3 treatments. This study demonstrated that appropriately staged spectral control using LED lights could have positive effects on the immune performance, bone development, and production performance of caged layer chickens during their brooding and rearing periods.
Asunto(s)
Conducta Animal , Pollos , Crecimiento y Desarrollo , Vivienda para Animales , Luz , Animales , Conducta Animal/efectos de la radiación , Color , Femenino , Crecimiento y Desarrollo/efectos de la radiación , Vivienda para Animales/estadística & datos numéricos , Iluminación/estadística & datos numéricosRESUMEN
Photobiomodulation was explored to find evidence of stimulation during the development of newborn rats. A light chamber device was used, and rat pups were divided into groups after birth. Investigation of the process' security was performed before the full experiment. Following a protocol of alternating illumination and mother's presence during the first 13 days, we observed that, in the group that received photobiomodulation, the pups opened their eyes faster, indicating earlier achievement of maturity. The rate of weight gain also indicates faster metabolic activity in the group that was photostimulated. This study is the first step toward the use of photobiomodulation for premature newborn human babies.
Asunto(s)
Aceleración , Crecimiento y Desarrollo/efectos de la radiación , Terapia por Luz de Baja Intensidad , Nacimiento Prematuro/radioterapia , Animales , Animales Recién Nacidos , Peso Corporal/efectos de la radiación , Humanos , RatasRESUMEN
This study aimed to investigate the biological impact of exposure on domestic light emitting diodes (LED) lighting using the free-living nematode Caenorhabditis elegans as a model. Nematodes were separately exposed to white LED light covering the range of 380-750 nm, blue light at 450 nm and black light at 380-420 nm for one life cycle (egg to adult) with dark exposure as the control. Each light range induced stress to the nematode C. elegans such as reducing the number of the hatched eggs and/or delayed the maturation of the hatched eggs to the adult stage. In addition, it lowered or prevented the ability of adults to lay eggs and impaired the locomotion in the exposed worms. The observed type of biological stress was also associated with the production of reactive oxygen species (ROS) as compared to nematodes grown in the dark. It is concluded that the blue light component of white LED light may cause health problems, and further investigation is required to test commercial brands of white LEDs that emit different amounts of blue light.
Asunto(s)
Caenorhabditis elegans/efectos de la radiación , Exposición a Riesgos Ambientales/análisis , Luz , Iluminación , Modelos Teóricos , Animales , Caenorhabditis elegans/crecimiento & desarrollo , Caenorhabditis elegans/metabolismo , Crecimiento y Desarrollo/efectos de la radiación , Larva/crecimiento & desarrollo , Larva/efectos de la radiación , Estrés Oxidativo/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismoRESUMEN
PURPOSE: To assess health, growth and reproductive success of mammals exposed for multiple generations to levels of radium-226 known to occur in environments surrounding uranium mines and mills in Canada. METHODS: The study consisted of a control group and four treatment groups each containing 40 mice (20 males and 20 females) of the CBA/CaJ strain that were continuously exposed to a range of radium-226 levels via drinking water. Breeding was at 8-10 weeks of age and the study was concluded after three breeding cycles. RESULTS: When compared to control mice, constant consumption of drinking water containing 0.012, 0.076, 0.78 and 8.0 Bq/l of radium-226 over four generations of mice did not demonstrably affect physical condition, weight, pregnancy rate, number of pups per litter, sex ratio and bodyweight gain of pups. Between generations, the observed differences in pregnancy rates that were noted in all groups, including controls, seemed to directly correlate with the weight and age of the females at breeding. CONCLUSIONS: Based on the endpoints measured on four generations of mice, there is no indication that the consumption of radium-226 via drinking water (at activity concentrations up to 8.0 Bq/l) affects health, growth and reproductive fitness.
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Agua Potable/química , Ambiente , Crecimiento y Desarrollo/efectos de la radiación , Salud , Radio (Elemento)/efectos adversos , Reproducción/efectos de la radiación , Contaminantes Radiactivos del Agua/efectos adversos , Envejecimiento/efectos de la radiación , Partículas alfa/efectos adversos , Animales , Peso Corporal/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Femenino , Tamaño de la Camada/efectos de la radiación , Masculino , Ratones , Embarazo , Índice de EmbarazoRESUMEN
The effects of extremely low frequency electromagnetic fields on rainbow trout growth performance, innate immunity and biochemical parameters were studied. Rainbow trout (17-18 g) were exposed to electromagnetic fields (15 Hz) at 0.01, 0.1, 0.5, 5 and 50 µT, for 1 h daily over period of 60 days. Growth performance of fish improved in different treatment groups, especially at 0.1, 0.5, 5 and 50 µT. Immunological parameters, specifically hemagglutinating titer, total antiprotease and α1-antiprotease levels in treatment groups, were also enhanced. Total protein and globulin contents in the serum of fish exposed to 0.1, 0.5, 5 and 50 µT were significantly higher than those in the control group. No significant differences were found in serum enzyme activities, namely aspartate aminotransferase and alanine aminotransferase of fish in all treatment groups. Conversely, alkaline phosphatase level decreased in fish exposed to 0.01 and 50 µT electromagnetic fields. Meanwhile, electromagnetic induction at 0.1, 0.5, 5 and 50 µT enhanced fish protection against Yersinia ruckeri. These results indicated that these specific electromagnetic fields had possible effects on growth performance, nonspecific immunity and disease resistance of rainbow trout.
Asunto(s)
Campos Electromagnéticos , Crecimiento y Desarrollo/efectos de la radiación , Inmunidad Innata/efectos de la radiación , Oncorhynchus mykiss/fisiología , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Animales , Acuicultura/métodos , Aspartato Aminotransferasas/sangre , Relación Dosis-Respuesta en la Radiación , Hemaglutinación/efectos de la radiación , Inhibidores de Proteasas/metabolismo , Yersinia ruckeri/inmunologíaRESUMEN
The aim of this study was to investigate the effects of a 2450 MHz electromagnetic field (EMF) (wireless internet frequency) on the growth and development of female Wistar rats. The study was conducted on three groups of rats. The prenatal and postnatal groups were exposed to EMF 1 h/day beginning from intrauterine and postnatal periods, respectively. The third group was the sham-exposed group. Growth, nutrition and vaginal opening (VO) were regularly monitored. Serum and tissue specimens were collected at puberty. Histological examinations, total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) measurements in ovary and brain tissues and also immunohistochemical staining of the hypothalamus were performed besides the determination of serum FSH, LH, E2 and IGF-1 values. Birth masses of the groups were similar (p > 0.05). Mass gain per day was significantly lower and the puberty was significantly later in the prenatal group. Brain and ovary TOS and OSI values in the prenatal group were significantly increased (p < 0.05) compared to the control group. Serum LH levels of the prenatal and postnatal groups were increased, although serum FSH, and E2 values did not differ among the groups (p > 0.05). Histological examinations of the specimens revealed no statistically significant difference between the groups (p > 0.05). Exposure to 2450 MHz EMF, particularly in the prenatal period, resulted in postnatal growth restriction and delayed puberty in female Wistar rats. Increased TOS and OSI values in the brain and ovary tissues can be interpreted as a sign of chronic stress induced by EMF. This is the first longitudinal study which investigates the effects of EMF induced by wireless internet on pubertal development beside growth.
Asunto(s)
Campos Electromagnéticos/efectos adversos , Crecimiento y Desarrollo/efectos de la radiación , Animales , Femenino , Hormonas/sangre , Estrés Oxidativo/efectos de la radiación , Ratas , Ratas Wistar , Factores de Tiempo , Tecnología InalámbricaRESUMEN
OBJECTIVES: The present study determined the effects of mobile phone (900 and 1800 MHz)-induced electromagnetic radiation (EMR) exposure on oxidative stress in the brain and liver as well as the element levels in growing rats from pregnancy to 6 weeks of age. METHODS: Thirty-two rats and their offspring were equally divided into three different groups: the control, 900 MHz, and 1800 MHz groups. The 900 MHz and 1800 MHz groups were exposed to EMR for 60 min/d during pregnancy and neonatal development. At the 4th, 5th, and 6th weeks of the experiment, brain samples were obtained. RESULTS: Brain and liver glutathione peroxidase activities, as well as liver vitamin A and ß-carotene concentrations decreased in the EMR groups, although brain iron, vitamin A, and ß-carotene concentrations increased in the EMR groups. In the 6th week, selenium concentrations in the brain decreased in the EMR groups. There were no statistically significant differences in glutathione, vitamin E, chromium, copper, magnesium, manganese, and zinc concentrations between the three groups. CONCLUSION: EMR-induced oxidative stress in the brain and liver was reduced during the development of offspring. Mobile phone-induced EMR could be considered as a cause of oxidative brain and liver injury in growing rats.
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Antioxidantes/metabolismo , Encéfalo/efectos de la radiación , Radiación Electromagnética , Crecimiento y Desarrollo , Hígado/metabolismo , Fármacos Neuroprotectores/metabolismo , Estrés Oxidativo/efectos de la radiación , Animales , Encéfalo/metabolismo , Femenino , Desarrollo Fetal/efectos de la radiación , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Crecimiento y Desarrollo/efectos de la radiación , Malondialdehído/metabolismo , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Ratas , Ratas Wistar , Vitamina E/metabolismoRESUMEN
While there have been a number of studies on the effects of photoperiod and duration of light and dark exposure, much less information is available on the importance of light intensity. This study investigated the effects of exposure of goldfish, Carassius auratus exposed to white fluorescent bulbs, and red (peak at 630nm), and green (530nm) light emitting diodes (LEDs) at approximately 0.9W/m(2) (12-h light:12-h dark) for four months on a number of hormones of the hypothalamus-pituitary-gonad (HPG) axis, in vivo and in vitro. We investigated the effects of native GnRH molecules (gonadotropin-releasing hormones; salmon GnRH, sGnRH; and chicken GnRH-II, cGnRH-II), gonadotropin hormones (GTHα; follicle-stimulating hormone, FSH-ß; luteinizing hormone, LH-ß2), kisspeptin 1 (Kiss1) and G protein-coupled receptor 54 (GPR54) mRNA levels. Furthermore, we measured LH and 17α-hydroxypregnenolone levels in plasma and we performed gonad histological observations. GnRHs, Kiss1, GPR54 and GTH mRNA and plasma LH and 17α-hydroxypregnenolone levels in the in vivo and in vitro groups exposed to green LEDs were significantly higher than the other groups. Histological analysis revealed the presence of oocytes in the yolk stage in fish exposed to green light. These results suggest that green wavelengths regulate the HPG axis and enhance sexual maturation in goldfish.
Asunto(s)
Carpa Dorada/crecimiento & desarrollo , Luz , Ovario/metabolismo , 17-alfa-Hidroxipregnenolona/sangre , Animales , Células Cultivadas , Femenino , Proteínas de Peces/sangre , Proteínas de Peces/genética , Expresión Génica , Hormona Liberadora de Gonadotropina/fisiología , Gonadotropinas/sangre , Crecimiento y Desarrollo/efectos de la radiación , Sistema Hipotálamo-Hipofisario , Hipotálamo/citología , Hipotálamo/metabolismo , Kisspeptinas/sangre , Kisspeptinas/genética , Hormona Luteinizante/sangre , Ovario/citología , Ovario/crecimiento & desarrollo , Receptores de Galanina/genética , Receptores de Galanina/metabolismoRESUMEN
The acute and chronic effects of radiation on children have been and will continue to be of great social, public health, scientific, and clinical importance. The focus of interest on ionizing radiation and children has been clear for over half a century and ranges from the effects of fallout from nuclear weapons testing to exposures from accidents, natural radiation, and medical procedures. There is a loosely stated notion that "children are three to five times more sensitive to radiation than adults." Is this really true? In fact, children are at greater risk for some health effects, but not all. For a few sequelae, children may be more resistant than adults. Which are those effects? How and why do they occur? While there are clear instances of increased risk of some radiation-induced tumors in children compared to adults, there are other tumor types in which there appears to be little or no difference in risk by age at exposure and some in which published models that assume the same relative increase in risks for child compared to adult exposures apply to nearly all tumor types are not supported by the scientific data. The United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR) has a task group producing a comprehensive report on the subject. The factors to be considered include relevant radiation sources; developmental anatomy and physiology; dosimetry; and stochastic, deterministic, and hereditary effects.
Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Accidente Nuclear de Fukushima , Tomografía Computarizada por Rayos X , Adulto , Niño , Femenino , Crecimiento y Desarrollo/efectos de la radiación , Humanos , Masculino , Neoplasias Inducidas por Radiación/diagnóstico por imagen , RadiometríaRESUMEN
Understanding the impact of noise on marine fauna at the population level requires knowledge about the vulnerability of different life-stages. Here we provide the first evidence that noise exposure during larval development produces body malformations in marine invertebrates. Scallop larvae exposed to playbacks of seismic pulses showed significant developmental delays and 46% developed body abnormalities. Similar effects were observed in all independent samples exposed to noise while no malformations were found in the control groups (4881 larvae examined). Malformations appeared in the D-veliger larval phase, perhaps due to the cumulative exposure attained by this stage or to a greater vulnerability of D-veliger to sound-mediated physiological or mechanical stress. Such strong impacts suggest that abnormalities and growth delays may also result from lower sound levels or discrete exposures during the D-stage, increasing the potential for routinely-occurring anthropogenic noise sources to affect recruitment of wild scallop larvae in natural stocks.
Asunto(s)
Organismos Acuáticos/crecimiento & desarrollo , Crecimiento y Desarrollo/efectos de la radiación , Larva/crecimiento & desarrollo , Metamorfosis Biológica/efectos de la radiación , Ruido/efectos adversos , Sonido/efectos adversos , Estrés Mecánico , Animales , Organismos Acuáticos/efectos de la radiación , Exposición a Riesgos Ambientales/efectos adversos , Larva/efectos de la radiaciónRESUMEN
An experimental approach was used to assess immunological biomarkers in the sera of young rats exposed in utero and postnatal to non-ionizing radiofrequency fields. Pregnant rats were exposed free-running, 2 h/day and 5 days/week to a 2.45 GHz Wi-Fi signal in a reverberation chamber at whole-body specific absorption rates (SAR) of 0, 0.08, 0.4, and 4 W/kg (with 10, 10, 12, and 9 rats, respectively), while cage control rats were kept in the animal facility (11 rats). Dams were exposed from days 6 to 21 of gestation and then three newborns per litter were further exposed from birth to day 35 postnatal. On day 35 after birth, all pups were sacrificed and sera collected. The screening of sera for antibodies directed against 15 different antigens related to damage and/or pathological markers was conducted using enzyme-linked immunosorbent assay (ELISA). No change in humoral response of young pups was observed, regardless of the types of biomarker and SAR levels. This study also provided some data on gestational outcome following in utero exposure to Wi-Fi signals. Mass evaluation of dams and pups and the number of pups per litter was monitored, and the genital tracts of young rats were observed for abnormalities by measuring anogenital distance. Under these experimental conditions, our observations suggest a lack of adverse effects of Wi-Fi exposure on delivery and general condition of the animals.
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Anticuerpos/sangre , Anticuerpos/inmunología , Exposición Materna/efectos adversos , Resultado del Embarazo , Tecnología Inalámbrica , Animales , Biomarcadores/sangre , Tamaño Corporal/efectos de la radiación , Parto Obstétrico , Femenino , Estudios de Seguimiento , Crecimiento y Desarrollo/efectos de la radiación , Tamaño de la Camada/efectos de la radiación , Embarazo , Ondas de Radio/efectos adversos , Ratas , Ratas WistarRESUMEN
Despite the fact that no plausible biological mechanism has yet been identified how electromagnetic fields below recommended exposure limits could negatively affect health of animals or humans, many experiments have been performed in various animal species, mainly mice and rats, to investigate the possible effects on growth and development. While older studies often suffered from sub-optimal exposure conditions, recent investigations, using sophisticated exposure devices and thus preventing thermal effects, have been performed without these limitations. In principle, two types of studies can be addressed: those which have investigated the carcinogenic or co-carcinogenic effects of exposure in developing animals, and those which have been done in developing animals without the focus on carcinogenic or co-carcinogenic effects. In both areas, the vast majority of publications did not show adverse effects. The largest study so far has been done in normal mice which have been chronically exposed to UMTS signals up to 1.3 W/kg SAR, thus 16 times higher than the whole-body exposure limit for humans. Even after four generations, no systematic or dose-dependent alterations in development or fertility could be found, supporting the view that negative effects on humans are very unlikely. Ongoing experiments in our laboratory investigate the effects of head-only exposure in rats (up to 10 W/kg local SAR) which are exposed from 14 days of age daily for 2 h. A battery of behavioral tests is performed in young, adult, and pre-senile animals. The results will help to clarify possible effects of exposure on brain development.
Asunto(s)
Crecimiento y Desarrollo/efectos de la radiación , Ondas de Radio/efectos adversos , Animales , Exposición a Riesgos Ambientales/efectos adversos , Hormonas/metabolismo , Humanos , Metabolismo/efectos de la radiaciónRESUMEN
The depletion of stratospheric ozone above the Arctic regions may increase the amount of UV-B radiation to which the northern ecosystems are exposed. In this paper, we examine the hypothesis that supplemental UV-B radiation may affect the growth rate and photosynthesis of boreal peatland plants and could thereby affect the carbon uptake of these ecosystems. In this study, we report the effects of 3-year exposure to elevated UV-B radiation (46% above ambient) on the photosynthetic performance and ultrastructure of a boreal sedge Eriophorum russeolum and a moss Warnstorfia exannulata. The experiment was conducted on a natural fen ecosystem at Sodankylä in northern Finland. The effects of UV-B radiation on the light response of E. russeolum CO(2) assimilation and the maximal photochemical efficiency of photosystem II in a dark-adapted state (F(v)/F(m)) were measured in the field. In addition, the effect of supplemental UV-B radiation on organelles of photosynthetic cells was studied by electron microscopy. The UV-B treatment had no effect on the CO(2) assimilation rate of either species, nor did it affect the structure of the cell organelles. On chlorophyll fluorescence, the UV-B exposure had only a temporary effect during the third exposure year. Our results suggested that in a natural ecosystem, even long-term exposure to reasonably elevated UV-B radiation levels does not affect the photosynthesis of peatland plants.
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Bryopsida/efectos de la radiación , Cyperaceae/efectos de la radiación , Fotosíntesis/efectos de la radiación , Rayos Ultravioleta , Bryopsida/fisiología , Bryopsida/ultraestructura , Respiración de la Célula/efectos de la radiación , Clorofila/metabolismo , Cyperaceae/fisiología , Cyperaceae/ultraestructura , Crecimiento y Desarrollo/efectos de la radiaciónRESUMEN
Obesity is increasingly prevalent in affluent societies and portends considerable morbidity. This is especially true in children with acute lymphoblastic leukemia (ALL) in whom the metabolic syndrome may begin during therapy, demanding clarification of the trajectory of weight gain so that effective interventions may be developed. In this retrospective study of body mass index from a single institution over a 20-year period, almost 15% of children with ALL were at risk of overweight or frankly overweight (body mass index >85th centile) at diagnosis. This proportion increased steadily, reaching 40% at the end of treatment. Strategies to limit weight gain will have to be instituted early in the management of children with ALL, and will probably have to be maintained throughout and after the completion of active treatment.
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Antineoplásicos Hormonales/efectos adversos , Crecimiento y Desarrollo/efectos de los fármacos , Obesidad/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras , Prednisolona/efectos adversos , Radioterapia/efectos adversos , Índice de Masa Corporal , Niño , Preescolar , Terapia Combinada/efectos adversos , Femenino , Crecimiento y Desarrollo/efectos de la radiación , Humanos , Masculino , Síndrome Metabólico/inducido químicamente , Síndrome Metabólico/epidemiología , Obesidad/inducido químicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Prevalencia , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Rupert Riedl's concept of burden forms a causal hypothesis on organismic integration and evolutionary constraints. Defined as the hierarchically nested interdependence of characters within the organism, burden was seen as (1) defining and conserving body plans and (2) constraining and directing evolutionary trajectories. A review of the components of the burden concept reveals important consistencies with the modern tenets of evo-devo. This concept differs from the current consensus of evolutionary theory in that it (1) grants evolution less options for changing tightly integrated, "locked-in" characters and (2) in deducing from this an ever decreasing freedom for evolution, with cyclism and typostrophism as resulting macroevolutionary phenomena. Despite these differences, I show that the burden concept was consistent with most major tenets of the Modern Synthesis, and Riedl attempted to explain patterns of large-scale evolutionary trends exclusively by microevolutionary (gradualistic) processes. The burden concept is fruitful and unique in its focus on hierarchically nested constraints and resembles the hierarchical architecture of gene regulatory networks. However, such networks are more high-dimensional and most of their components appear to be easier to evolve than Riedl's burden. Yet in combination with evolvability, a modified concept of burden might contribute substantially to the understanding of organismic integration and the long-term evolution of body plans.
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Evolución Biológica , Crecimiento y Desarrollo , Selección Genética , Animales , Tipificación del Cuerpo/genética , Tipificación del Cuerpo/fisiología , Biología Evolutiva/historia , Crecimiento y Desarrollo/genética , Crecimiento y Desarrollo/efectos de la radiación , Historia del Siglo XX , Filogenia , Selección Genética/genética , Selección Genética/fisiologíaRESUMEN
The synergism between red and blue light in the control of plant growth and development requires the coaction of the red light photoreceptor phytochrome B (phyB) and the blue light and UV-A receptor cryptochromes (cry). Here, we describe the mechanism of the coaction of these photoreceptors in controlling both development and physiology. In seedlings grown under red light, a transient supplement with blue light induced persistent changes in the transcriptome and growth patterns. Blue light enhanced the expression of the transcription factors LONG HYPOCOTYL 5 (HY5) and HOMOLOG OF HY5 (HYH) and of SUPPRESSOR OF PHYA 1 (SPA1) and SPA4. HY5 and HYH enhanced phyB signaling output beyond the duration of the blue light signal, and, contrary to their known role as repressors of phyA signaling, SPA1 and SPA4 also enhanced phyB signaling. These observations demonstrate that the mechanism of synergism involves the promotion by cry of positive regulators of phyB signaling. The persistence of the light-derived signal into the night commits the seedling to a morphogenetic and physiological program consistent with a photosynthetic lifestyle.
Asunto(s)
Arabidopsis/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Crecimiento y Desarrollo/efectos de la radiación , Luz , Transducción de Señal/efectos de la radiación , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Ciclo Celular/metabolismo , Color , Citocromos/metabolismo , Proteínas de Unión al ADN , Proteínas Nucleares/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Fitocromo B/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismoRESUMEN
Male and female mice (C57BL) were chronically exposed (life-long, 24 h/day) to mobile phone communication electromagnetic fields at approximately 1966 MHz (UMTS). Their development and fertility were monitored over four generations by investigating histological, physiological, reproductive and behavioral functions. The mean whole-body SARs, calculated for adult animals at the time of mating, were 0 (sham), 0.08, 0.4 and 1.3 W/kg. Power densities were kept constant for each group (0, 1.35, 6.8 and 22 W/m(2)), resulting in varying SARs due to the different numbers of adults and pups over the course of the experiment. The experiment was done in a blind fashion. The results show no harmful effects of exposure on the fertility and development of the animals. The number and the development of pups were not affected by exposure. Some data, albeit without a clear dose-response relationship, indicate effects of exposure on food consumption that is in accordance with some data published previously. In summary, the results of this study do not indicate harmful effects of long-term exposure of mice to UMTS over several generations.