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The presence of positron emission tomography (PET) centers at most major hospitals worldwide, along with the improvement of PET scanner sensitivity and the introduction of total body PET systems, has increased the interest in the PET tracer development using the short-lived radionuclides carbon-11. In the last few decades, methodological improvements and fully automated modules have allowed the development of carbon-11 tracers for clinical use. Radiolabeling natural compounds with carbon-11 by substituting one of the backbone carbons with the radionuclide has provided important information on the biochemistry of the authentic compounds and increased the understanding of their in vivo behavior in healthy and diseased states. The number of endogenous and natural compounds essential for human life is staggering, ranging from simple alcohols to vitamins and peptides. This review collates all the carbon-11 radiolabeled endogenous and natural exogenous compounds synthesised to date, including essential information on their radiochemistry methodologies and preclinical and clinical studies in healthy subjects.
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Tomografía de Emisión de Positrones , Radiofármacos , Humanos , Radioisótopos de Carbono/química , RadioquímicaRESUMEN
Chemically processed methylammonium tin-triiodide (CH3NH3SnI3) films include Sn in different oxidation states, leading to poor stability and low power conversion efficiency of the resulting solar cells (PSCs). The development of absorbers with Sn [2+] only has been identified as one of the critical steps to develop all Sn-based devices. Here, we report on coevaporation of CH3NH3I and SnI2 to obtain absorbers with Sn being only in the preferred oxidation state [+2] as confirmed by X-ray photoelectron spectroscopy. The Sn [4+]-free absorbers exhibit smooth highly crystalline surfaces and photoluminescence measurements corroborating their excellent optoelectronic properties. The films show very good stability under heat and light. Photoluminescence quantum yields up to 4 × 10-3 translate in a quasi Fermi-level splittings exceeding 850 meV under one sun equivalent conditions showing high promise in developing lead-free, high efficiency, and stable PSCs.
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BACKGROUND: Pressure-support ventilation may worsen lung damage due to increased dynamic transpulmonary driving pressure. The authors hypothesized that, at the same tidal volume (VT) and dynamic transpulmonary driving pressure, pressure-support and pressure-controlled ventilation would yield comparable lung damage in mild lung injury. METHODS: Male Wistar rats received endotoxin intratracheally and, after 24 h, were ventilated in pressure-support mode. Rats were then randomized to 2 h of pressure-controlled ventilation with VT, dynamic transpulmonary driving pressure, dynamic transpulmonary driving pressure, and inspiratory time similar to those of pressure-support ventilation. The primary outcome was the difference in dynamic transpulmonary driving pressure between pressure-support and pressure-controlled ventilation at similar VT; secondary outcomes were lung and diaphragm damage. RESULTS: At VT = 6 ml/kg, dynamic transpulmonary driving pressure was higher in pressure-support than pressure-controlled ventilation (12.0 ± 2.2 vs. 8.0 ± 1.8 cm H2O), whereas static transpulmonary driving pressure did not differ (6.7 ± 0.6 vs. 7.0 ± 0.3 cm H2O). Diffuse alveolar damage score and gene expression of markers associated with lung inflammation (interleukin-6), alveolar-stretch (amphiregulin), epithelial cell damage (club cell protein 16), and fibrogenesis (metalloproteinase-9 and type III procollagen), as well as diaphragm inflammation (tumor necrosis factor-α) and proteolysis (muscle RING-finger-1) were comparable between groups. At similar dynamic transpulmonary driving pressure, as well as dynamic transpulmonary driving pressure and inspiratory time, pressure-controlled ventilation increased VT, static transpulmonary driving pressure, diffuse alveolar damage score, and gene expression of markers of lung inflammation, alveolar stretch, fibrogenesis, diaphragm inflammation, and proteolysis compared to pressure-support ventilation. CONCLUSIONS: In the mild lung injury model use herein, at the same VT, pressure-support compared to pressure-controlled ventilation did not affect biologic markers. However, pressure-support ventilation was associated with a major difference between static and dynamic transpulmonary driving pressure; when the same dynamic transpulmonary driving pressure and inspiratory time were used for pressure-controlled ventilation, greater lung and diaphragm injury occurred compared to pressure-support ventilation.
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Diafragma/lesiones , Diafragma/fisiopatología , Lesión Pulmonar/etiología , Lesión Pulmonar/fisiopatología , Respiración con Presión Positiva/efectos adversos , Respiración con Presión Positiva/métodos , Animales , Masculino , Respiración con Presión Positiva/normas , Ratas , Ratas Wistar , Mecánica Respiratoria/fisiología , Volumen de Ventilación Pulmonar/fisiologíaRESUMEN
BACKGROUND: This study hypothesized that, in experimental mild acute respiratory distress syndrome, lung damage caused by high tidal volume (VT) could be attenuated if VT increased slowly enough to progressively reduce mechanical heterogeneity and to allow the epithelial and endothelial cells, as well as the extracellular matrix of the lung to adapt. For this purpose, different strategies of approaching maximal VT were tested. METHODS: Sixty-four Wistar rats received Escherichia coli lipopolysaccharide intratracheally. After 24 h, animals were randomly assigned to receive mechanical ventilation with VT = 6 ml/kg for 2 h (control); VT = 6 ml/kg during hour 1 followed by an abrupt increase to VT = 22 ml/kg during hour 2 (no adaptation time); VT = 6 ml/kg during the first 30 min followed by a gradual VT increase up to 22 ml/kg for 30 min, then constant VT = 22 ml/kg during hour 2 (shorter adaptation time); and a more gradual VT increase, from 6 to 22 ml/kg during hour 1 followed by VT = 22 ml/kg during hour 2 (longer adaptation time). All animals were ventilated with positive end-expiratory pressure of 3 cm H2O. Nonventilated animals were used for molecular biology analysis. RESULTS: At 2 h, diffuse alveolar damage score and heterogeneity index were greater in the longer adaptation time group than in the control and shorter adaptation time animals. Gene expression of interleukin-6 favored the shorter (median [interquartile range], 12.4 [9.1-17.8]) adaptation time compared with longer (76.7 [20.8 to 95.4]; P = 0.02) and no adaptation (65.5 [18.1 to 129.4]) time (P = 0.02) strategies. Amphiregulin, metalloproteinase-9, club cell secretory protein-16, and syndecan showed similar behavior. CONCLUSIONS: In experimental mild acute respiratory distress syndrome, lung damage in the shorter adaptation time group compared with the no adaptation time group was attenuated in a time-dependent fashion by preemptive adaptation of the alveolar epithelial cells and extracellular matrix. Extending the adaptation period increased cumulative power and did not prevent lung damage, because it may have exposed animals to injurious strain earlier and for a longer time, thereby negating any adaptive benefit.
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Lesión Pulmonar/prevención & control , Volumen de Ventilación Pulmonar , Adaptación Fisiológica , Animales , Interleucina-6/genética , Masculino , Respiración con Presión Positiva , Ratas , Ratas Wistar , Síndrome de Dificultad Respiratoria/complicaciones , Volumen de Ventilación Pulmonar/fisiologíaRESUMEN
BACKGROUND: The authors hypothesized that low tidal volume (VT) would minimize ventilator-induced lung injury regardless of the degree of mechanical power. The authors investigated the impact of power, obtained by different combinations of VT and respiratory rate (RR), on ventilator-induced lung injury in experimental mild acute respiratory distress syndrome (ARDS). METHODS: Forty Wistar rats received Escherichia coli lipopolysaccharide intratracheally. After 24 h, 32 rats were randomly assigned to be mechanically ventilated (2 h) with a combination of different VT (6 ml/kg and 11 ml/kg) and RR that resulted in low and high power. Power was calculated as energy (ΔP,L/E,L) × RR (ΔP,L = transpulmonary driving pressure; E,L = lung elastance), and was threefold higher in high than in low power groups. Eight rats were not mechanically ventilated and used for molecular biology analysis. RESULTS: Diffuse alveolar damage score, which represents the severity of edema, atelectasis, and overdistension, was increased in high VT compared to low VT, in both low (low VT: 11 [9 to 14], high VT: 18 [15 to 20]) and high (low VT: 19 [16 to 25], high VT: 29 [27 to 30]) power groups. At high VT, interleukin-6 and amphiregulin expressions were higher in high-power than in low-power groups. At high power, amphiregulin and club cell protein 16 expressions were higher in high VT than in low VT. Mechanical energy and power correlated well with diffuse alveolar damage score and interleukin-6, amphiregulin, and club cell protein 16 expression. CONCLUSIONS: In experimental mild ARDS, even at low VT, high mechanical power promoted ventilator-induced lung injury. To minimize ventilator-induced lung injury, low VT should be combined with low power.
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Síndrome de Dificultad Respiratoria/fisiopatología , Mecánica Respiratoria/fisiología , Mucosa Respiratoria/fisiopatología , Volumen de Ventilación Pulmonar/fisiología , Animales , Distribución Aleatoria , Ratas , Ratas Wistar , Síndrome de Dificultad Respiratoria/patología , Mucosa Respiratoria/patologíaRESUMEN
Natural toxins produced by freshwater cyanobacteria, such as cylindrospermopsin, have been regarded as an emergent environmental threat. Despite the risks for food safety, the impact of these water contaminants in agriculture is not yet fully understood. Carrots (Daucus carota) are root vegetables, extensively consumed worldwide with great importance for human nourishment and economy. It is, therefore, important to evaluate the possible effects of using water contaminated with cyanotoxins on carrot cultivation. The aim of this work was to investigate cylindrospermopsin effects on D. carota grown in soil and irrigated for 30 days, with a Chrysosporum ovalisporum extract containing environmentally relevant concentrations of cylindrospermopsin (10 and 50 µg/L). The parameters evaluated were plant growth, photosynthetic capacity, and nutritional value (mineral content) in roots of carrots, as these are the edible parts of this plant crop. The results show that, exposure to cylindrospermopsin did not have a clear negative effect on growth or photosynthesis of D. carota, even leading to an increase of both parameters. However, alterations in mineral contents were detected after exposure to crude extracts of C. ovalisporum containing cylindrospermopsin. A general decline was observed for most minerals (Ca, Mg, Na, Fe, Mn, Zn, Mo, and P), although an increase was shown in the case of K and Cu, pointing to a possible interference of the cyanobacterial extract in mineral uptake. This study is the first to evaluate the effects of C. ovalisporum extracts on a root vegetable, however, more research is necessary to understand the effects of this toxin in environmentally relevant scenarios.
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Aphanizomenon , Toxinas Bacterianas/toxicidad , Daucus carota/fisiología , Minerales/metabolismo , Fotosíntesis/efectos de los fármacos , Uracilo/análogos & derivados , Contaminantes Químicos del Agua/toxicidad , Alcaloides , Toxinas de Cianobacterias , Contaminantes del Suelo/toxicidad , Uracilo/toxicidadRESUMEN
This study aimed to understand the morphophysiological responses and primary metabolism of tomato seedlings subjected to mild levels of nitrogen and/or water deficit (50% N and/or 50% W). After 16 days of exposure, plants grown under the combined deficit showed similar behavior to the one found upon exposure to single N deficit. Both N deficit treatments resulted in a significantly lower dry weight, leaf area, chlorophyll content, and N accumulation but in a higher N use efficiency when compared to control (CTR) plants. Moreover, concerning plant metabolism, at the shoot level, these two treatments also responded in a similar way, inducing higher C/N ratio, nitrate reductase (NR) and glutamine synthetase (GS) activity, expression of RuBisCO encoding genes as well as a downregulation of GS2.1 and GS2.2 transcripts. Interestingly, plant metabolic responses at the root level did not follow the same pattern, with plants under combined deficit behaving similarly to W deficit plants, resulting in enhanced nitrate and proline concentrations, NR activity, and an upregulation of GS1 and NR genes than in CTR plants. Overall, our data suggest that the N remobilization and osmoregulation strategies play a relevant role in plant acclimation to these abiotic stresses and highlight the complexity of plant responses under a combined N+W deficit.
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This study aims to perform a broad analysis of the antioxidant (AOX) responses of young tomato plants exposed to single and combined mild nitrogen (N) and water deficits through the evaluation of oxidative biomarkers, non-enzymatic and enzymatic AOX components. 'Micro-Tom' seedlings were subjected to four treatments: control (CTR; 100%N + 100%W), N deficit (N; 50%N), water deficit (W; 50%W), and combined deficits (N + W; 50%N + 50%W). An enhancement of several non-enzymatic and enzymatic components was found in plants subjected to N + W deficit, which presented higher anthocyanins accumulation (up to 103%) as well as higher levels of superoxide dismutase (SOD) transcripts at root level and of ascorbate peroxidase (APX) and catalase (CAT) transcripts at shoot level. This increase in the gene expression was also translated in augmented SOD (up to 202%), APX (up to 155%) and CAT (up to 108%) activity compared to CTR plants and the single deficits. Overall, tomato plants were able to employ defense strategies to cope with this combined deficit, as demonstrated by the higher total AOX capacity (up to 87%) compared to the single deficits, which contributed to the maintenance of their redox homeostasis, with unchanged values of lipid peroxidation and hydrogen peroxide compared with CTR plants.
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BACKGROUND: There is limited information related to COVID-19 in pregnancy. OBJECTIVES: Evaluate the impact of COVID-19 during pregnancy.Search strategy: Searches were systematically carried out in PubMed, Scopus database and WHO database.Selection criteria: Studies with information related to the effects of COVID-19 in pregnancy, concerning maternal, obstetric, and neonatal outcomes were included.Data collection and analysis: Data were extracted for systematic review following PRISMA guidelines. CARE and STROBE were used to evaluate the quality of data.Main Results: A total of 8 studies involving 95 pregnant women and 51 neonates were included. Overall, the quality was considered good in four studies, moderate in three and poor in one. Among pregnant women, 26% had a history of epidemiological exposure to SARS-CoV-2. The most common symptoms presented were fever (55%), cough (38%) and fatigue (11%). In 50 deliveries, 94% were cesarean sections and 35% were preterm births. Of the 51 neonates, 20% had low birth weight and 1 tested positive for Sars-CoV-2. There was 1 neonatal death, not related to the viral infection, and no cases of severe neonatal asphyxia. CONCLUSIONS: The information compiled in this systematic review may help healthcare providers administer the best possible care.
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COVID-19 , Complicaciones Infecciosas del Embarazo , Nacimiento Prematuro , COVID-19/epidemiología , Femenino , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , SARS-CoV-2RESUMEN
Chromosome segregation requires sister chromatid resolution. Condensins are essential for this process since they organize an axial structure where topoisomerase II can work. How sister chromatid separation is coordinated with chromosome condensation and decatenation activity remains unknown. We combined four-dimensional (4D) microscopy, RNA interference (RNAi), and biochemical analyses to show that topoisomerase II plays an essential role in this process. Either depletion of topoisomerase II or exposure to specific anti-topoisomerase II inhibitors causes centromere nondisjunction, associated with syntelic chromosome attachments. However, cells degrade cohesins and timely exit mitosis after satisfying the spindle assembly checkpoint. Moreover, in topoisomerase II-depleted cells, Aurora B and INCENP fail to transfer to the central spindle in late mitosis and remain tightly associated with centromeres of nondisjoined sister chromatids. Also, in topoisomerase II-depleted cells, Aurora B shows significantly reduced kinase activity both in S2 and HeLa cells. Codepletion of BubR1 in S2 cells restores Aurora B kinase activity, and consequently, most syntelic attachments are released. Taken together, our results support that topoisomerase II ensures proper sister chromatid separation through a direct role in centromere resolution and prevents incorrect microtubule-kinetochore attachments by allowing proper activation of Aurora B kinase.
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Centrómero/fisiología , ADN-Topoisomerasas de Tipo II/fisiología , Mitosis/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Animales , Aurora Quinasa B , Aurora Quinasas , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Proteínas Cromosómicas no Histona/metabolismo , Segregación Cromosómica/fisiología , ADN-Topoisomerasas de Tipo II/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Activación Enzimática , Células HeLa , Humanos , Cinetocoros/fisiología , Microtúbulos/fisiología , Interferencia de ARN/fisiología , Intercambio de Cromátides Hermanas/fisiología , Huso Acromático/fisiología , Inhibidores de Topoisomerasa IIRESUMEN
In the last decades, the concentration of atmospheric CO2 and the average temperature have been increasing, and this trend is expected to become more severe in the near future. Additionally, environmental stresses including drought, salinity, UV-radiation, heavy metals, and toxic elements exposure represent a threat for ecosystems and agriculture. Climate and environmental changes negatively affect plant growth, biomass and yield production, and also enhance plant susceptibility to pests and diseases. Silicon (Si), as a beneficial element for plants, is involved in plant tolerance and/or resistance to various abiotic and biotic stresses. The beneficial role of Si has been shown in various plant species and its accumulation relies on the root's uptake capacity. However, Si uptake in plants depends on many biogeochemical factors that may be substantially altered in the future, affecting its functional role in plant protection. At present, it is not clear whether Si accumulation in plants will be positively or negatively affected by changing climate and environmental conditions. In this review, we focused on Si interaction with the most important factors of global change and environmental hazards in plants, discussing the potential role of its application as an alleviation strategy for climate and environmental hazards based on current knowledge.
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Metaloides , Silicio , Cambio Climático , Ecosistema , PlantasRESUMEN
This article summarises the proceedings of a continuing professional development session on the use of intravenous contrast media in hybrid imaging for radiographers, technologists, and nurses. The session was jointly organised by the British Nuclear Medicine Society Radiographer, Technologist, and Nurses Group and the Society of Radiographers at the 47th Annual Spring Meeting of the British Nuclear Medicine Society held in Oxford, UK, on 1-3 April 2019.
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Medios de Contraste/administración & dosificación , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único/métodos , Administración Intravenosa , Humanos , RiesgoRESUMEN
The continuous increase of the human population worldwide has led to an increase of pharmaceuticals' consumption, such as diclofenac (DCF), a widely used non-steroidal anti-inflammatory drug (NSAID), that is not removed by wastewater treatment processes. Although there is some research regarding the effects of DCF on animals and aquatic invertebrates, information concerning its influence on plants' metabolism is still scarce. Through an integrated approach, using combined biochemical and molecular biology techniques, this work aimed to evaluate the phytotoxicity of DCF in Solanum lycopersicum L., focusing on the primary plant processes: nitrogen (N) assimilation and photosynthesis. The exposure of tomato plants to increasing concentrations of DCF (0, 0.5, and 5 mg L-1) revealed that glutamine synthetase (GS) was differentially affected, in an organ-dependent manner, by this contaminant at the gene expression, protein, and activity levels, with an increased activity of 0.2-fold in shoots of plants treated with the lowest concentration of DCF although a general decrease was registered for the SlGS gene family expression, revealing that post-translational regulation was in order, since GS2 polypeptide content did not change. Glutamate dehydrogenase (GDH) activity was generally enhanced, accompanied by increases of 0.4- to 1.9-fold in proline levels, revealing GDH as an important compensatory route for both N assimilation and proline production under stressful conditions. No alterations in most photosynthetic endpoints were noticed after DCF treatments, but small decreases of 0.1- to 0.8-fold in the accumulation of RuBisCO-encoding transcripts were observed, along with a reduction in starch content. Some alterations in the soluble polypeptide profile were also detected in response to DCF, evidencing the participation of some stress-related proteins in the plant's response to DCF.
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Solanum lycopersicum , Carbono , Diclofenaco , Glutamato Deshidrogenasa , Glutamato-Amoníaco Ligasa , Nitrógeno , ProlinaRESUMEN
Bone scintigraphy is one of the most common nuclear medicine tests. Previous work investigated the effectiveness of an asymmetric window (ASW) for planar bone scintigraphy using simulation and phantom data. Phantom studies concluded that the ASW improved both the resolution and the contrast-to-noise ratio when imaging objects with high scatter. The aim of this study was to confirm this improvement increased image quality in patients. This study also investigated whether the differences between a symmetric window (SW) and an ASW depended on body mass index. Methods: Fifty-eight patients had 2 scans: a standard scan using an SW of 140 keV ± 10% and a scan using an ASW of 140 keV + 10% and - 7.5%. Three readers independently compared the 2 image sets and scored them using a 5-score scale (ranging from 1 = ASW better [clinically important] to 5 = SW better [clinically important]). Scores from all radiologists were pooled and analyzed statistically. A P value of less than 0.05 was considered statistically significant. Results: In 93 cases (53%), the readers scored the ASW images better than the SW images. In 5 cases (3%), the ASW images were preferred, with the difference considered clinically important; there were no cases in which the SW was similarly preferred. For the sign test, we determined whether the total of 93 scores of 1 or 2 (ASW preferred) was significantly different from the 15 scores of 4 or 5 (SW preferred). The P value was less than 0.00001, demonstrating that the difference was significant. Conclusion: In patients undergoing bone scintigraphy, ASW provided an improvement in image quality that in some cases was judged clinically important.
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Huesos/diagnóstico por imagen , Cintigrafía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Sensibilidad y Especificidad , Relación Señal-Ruido , Imagen de Cuerpo EnteroRESUMEN
The wide range of applications of rare earth elements (REE) is leading to their occurrence in worldwide aquatic environments. Among the most popular REE is Neodymium (Nd), being widely used in permanent magnets, lasers, and glass additives. Neodymium-iron-boron (NdFeB) magnets is the main application of Nd since they are used in electric motors, hard disk drives, speakers and generators for wind turbines. Recent studies have already evaluated the toxic potential of different REE, but no information is available on the effects of Nd towards marine bivalves. Thus, the present study evaluated the biochemical alterations caused by Nd in the mussel Mytilus galloprovincialis exposed to this element for 28 days. The results obtained clearly demonstrated that Nd was accumulated by mussels, leading to mussel's metabolic capacity increase and GLY expenditure, in an attempt to fuel up defense mechanisms. Antioxidant and biotransformation defenses were insufficient in the elimination of ROS excess, resulting from the presence of Nd and increased electron transport system activity, which caused cellular damages (measured by lipid peroxidation) and loss of redox balance (assessed by the ratio between reduced and oxidized glutathione). The results obtained clearly highlight the potential toxicity of REEs and, in particular of Nd, with impacts at cellular level, which may have consequences in mussel's survival, growth and reproduction, affecting mussel's population.
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Imanes/química , Metales de Tierras Raras/toxicidad , Mytilus/efectos de los fármacos , Neodimio/toxicidad , Animales , Homeostasis/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Metales de Tierras Raras/farmacología , Mytilus/metabolismo , Oxidación-Reducción , Contaminantes Químicos del Agua/toxicidadRESUMEN
Analysis of terminal deletion chromosomes indicates that a sequence-independent mechanism regulates protection of Drosophila telomeres. Mutations in Drosophila DNA damage response genes such as atm/tefu, mre11, or rad50 disrupt telomere protection and localization of the telomere-associated proteins HP1 and HOAP, suggesting that recognition of chromosome ends contributes to telomere protection. However, the partial telomere protection phenotype of these mutations limits the ability to test if they act in the epigenetic telomere protection mechanism. We examined the roles of the Drosophila atm and atr-atrip DNA damage response pathways and the nbs homolog in DNA damage responses and telomere protection. As in other organisms, the atm and atr-atrip pathways act in parallel to promote telomere protection. Cells lacking both pathways exhibit severe defects in telomere protection and fail to localize the protection protein HOAP to telomeres. Drosophila nbs is required for both atm- and atr-dependent DNA damage responses and acts in these pathways during DNA repair. The telomere fusion phenotype of nbs is consistent with defects in each of these activities. Cells defective in both the atm and atr pathways were used to examine if DNA damage response pathways regulate telomere protection without affecting telomere specific sequences. In these cells, chromosome fusion sites retain telomere-specific sequences, demonstrating that loss of these sequences is not responsible for loss of protection. Furthermore, terminally deleted chromosomes also fuse in these cells, directly implicating DNA damage response pathways in the epigenetic protection of telomeres. We propose that recognition of chromosome ends and recruitment of HP1 and HOAP by DNA damage response proteins is essential for the epigenetic protection of Drosophila telomeres. Given the conserved roles of DNA damage response proteins in telomere function, related mechanisms may act at the telomeres of other organisms.
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Daño del ADN , Epigénesis Genética , Telómero/ultraestructura , Alelos , Animales , Apoptosis , Ciclo Celular , Mapeo Cromosómico , Cruzamientos Genéticos , Reparación del ADN , Proteínas de Drosophila , Drosophila melanogaster , Eliminación de Gen , Mitosis , Factores de TiempoRESUMEN
Cyanobacteria and cyanotoxins constitute a serious environmental and human health problem. Moreover, concerns are raised with the use of contaminated water in agriculture and vegetable production as this can lead to food contamination and human exposure to toxins as well as impairment in crop development and productivity. The objective of this work was to assess the susceptibility of two green vegetables, spinach and lettuce, to the cyanotoxins microcystin (MC) and cylindrospermopsin (CYN), individually and in mixture. The study consisted of growing both vegetables in hydroponics, under controlled conditions, for 21 days in nutrient medium doped with MC or CYN at 10 µg/L and 50 µg/L, or CYN/MC mixture at 5 + 5 µg/L and 25 + 25 µg/L. Extracts from M. aeruginosa and C. ovalisporum were used as sources of toxins. The study revealed growth inhibition of the aerial part (Leaves) in both species when treated with 50µg/L of MC, CYN and CYN/MC mixture. MC showed to be more harmful to plant growth than CYN. Moreover spinach leaves growth was inhibited by both 5 + 5 and 25 + 25 µg/L CYN/MC mixtures, whereas lettuce leaves growth was inhibited only by 25 + 25 µg/L CYN/MC mixture. Overall, growth data evidence increased sensitivity of spinach to cyanotoxins in comparison to lettuce. On the other hand, plants exposed to CYN/MC mixture showed differential accumulation of CYN and MC. In addition, CYN, but not MC, was translocated from the roots to the leaves. CYN and MC affected the levels of minerals particularly in plant roots. The elements most affected were Ca, K and Mg. However, in leaves K was the mineral that was affected by exposure to cyanotoxins.
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Cianobacterias/química , Contaminación de Alimentos/análisis , Lactuca/química , Microcistinas/análisis , Spinacia oleracea/química , Verduras/química , Contaminantes Químicos del Agua/análisis , Riego Agrícola , Bioacumulación , Lactuca/crecimiento & desarrollo , Microcistinas/toxicidad , Hojas de la Planta/química , Raíces de Plantas/química , Spinacia oleracea/crecimiento & desarrollo , Contaminantes Químicos del Agua/toxicidad , Contaminación del Agua/análisisRESUMEN
Introducción: El síndrome velocardiovacial (velocardiofacial syndrome - VCFS) es una entidad clínica heterogénea causada, en su mayoría, por una microdeleción en el cromosoma 22. Las principales características clínicas de este síndrome son: cambios en la morfología facial y del paladar, anomalías cardíacas congénitas, hipoplasia del timo, inmunodeficiencias con mayor riesgo de infección, hipoparatiroidismo, retraso mental y trastornos psiquiátricos. En la mayoría de los casos, la patología mental comórbida suele estar dentro del rango de los trastornos psicóticos.Métodos: Presentamos el caso clinico de una paciente de 34 años diagnosticada con SVCF con patologia cardíaca (comunicación interventricular con cierre espontáneo desde la infancia) y psicosis refractaria a varios antipsicóticos. Por tratarse de una paciente con mala respuesta al uso de varios antipsicóticos, inició tratamiento con clozapina. Teniendo en consideración los posibles efectos adversos del fármaco sobre la comorbilidad de VCFS, se realizó una revisión bibliográfica no sistemática en Pubmed sobre el tratamiento de la psicosis en VCFS con clozapina, con las palabras clave: síndrome velocardiofacial; clozapina.Resultados: No hay muchos estudios sobre el uso de psicofármacos en el tratamiento de la comorbilidad psiquiátrica en pacientes con VCFS. El tratamiento con clozapina en pacientes con VCFS debe considerarse teniendo en cuenta las particularidades de cada caso, sobre todo en casos con una mayor propensión a la psicosis refractaria, y, sobre todo, evaluando los riesgos y beneficios de su administración, siempre teniendo en cuenta que existe una mayor vulnerabilidad a los efectos adversos en la administración de fármacos en esta población.Discusión: En base al presente trabajo, se concluyó que el tratamiento de la psicosis en pacientes con VCFS sigue siendo un gran desafío dadas las vulnerabilidades clínicas de esta población. (AU)
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Humanos , Femenino , Adulto , Cromosomas Humanos Par 22 , Cardiopatías Congénitas , Hipoparatiroidismo , Discapacidad Intelectual , Antipsicóticos , Trastornos Psicóticos , PsiquiatríaRESUMEN
One of the most remarkable and yet poorly understood events during the cell cycle is how dispersed chromatin fragments are transformed into chromosomes every time cells undergo mitosis. It has been postulated that mitotic chromosomes might contain an axial scaffold that is involved in condensation but its molecules and structure have remained elusive. Recent data suggests that the condensin complex might indeed be an essential part of the scaffold that provides a platform for other proteins to localize and promote different aspects of chromosome condensation.