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In contrast to red blood cells, platelets float rather than sediment when a column of blood is placed in the gravitational field. By the analogy of erythrocyte sedimentation (ESR), it can be expressed with the platelet antisedimentation rate (PAR), which quantitates the difference in platelet count between the upper and lower halves of the blood column after 1 h of 1 g sedimentation. Venous blood samples from 21 healthy subjects were analyzed for PAR. After a 1-h sedimentation, the upper and lower fractions of blood samples were analyzed for platelet count, mean platelet volume (MPV), immature platelet fraction (IPF), and high-fluorescence IPF (H-IPF). The mechanisms behind platelet flotation were explored by further partitioning of the blood column, time-dependent measurements of platelet count and comparison with ESR. The structure and function of the platelets were assessed by electron microscopy (EM) and atomic force microscopy (AFM), and platelet aggregometry, respectively. Platelet antisedimentation is driven by density differences and facilitated by a size-exclusion mechanism caused by progressive erythrocyte sedimentation. The area under the curve (AUC) of the whole blood adenosine diphosphate (ADP) aggregation curves showed significant differences between the upper and lower samples (p < .005). AUC in the upper samples of 38% of healthy subjects exceeded the top of the normal range (53-122) suggesting that ascending platelets show an intensified ADP-induced aggregability ex vivo. H-IPF was significantly higher in the upper samples (p < .05). EM and AFM revealed that platelets in the upper samples were larger in volume and contained 1.6 times more alpha granules compared to platelets in the lower samples. Our results indicate that antisedimentation is able to differentiate platelet populations based on their structural and functional properties. Therefore, PAR may be a suitable laboratory parameter in various thromboinflammatory disorders.
It is less known that platelets do not sediment in response to gravitational force but float on the top of the blood column. This phenomenon is called antisedimentation, the rate of which, however, can be different, yet this feature has not been widely studied and used in clinical practice or diagnosis. We tested the idea that antisedimentation of platelets from venous blood samples can be a potential biomarker. We have found that platelet antisedimentation is driven by density differences and facilitated by a size-exclusion mechanism caused by progressive erythrocyte sedimentation and after 1-h upper and lower fractions develop. Interestingly, the aggregation curves showed significant differences between the upper and lower samples, suggesting that the ascending platelets show ex vivo hyperaggregability. Electron and atomic force microscopy revealed that platelets in the upper samples were larger in volume and contained more alpha granules than platelets in the lower samples. Subsequently, antisedimentation can be used to differentiate platelet populations based on their structural and functional properties; thus, it may be a promising biomarker for various thromboinflammatory disorders.
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Plaquetas , Eritrocitos , Humanos , Recuento de Plaquetas , Volúmen Plaquetario Medio , Adenosina DifosfatoRESUMEN
BACKGROUND Computer-aided design (CAD) has been used in the Nuss procedure to determine the bar length and shape. Despite computer aid, the shape and design remain quite intuitive. We tested a new algorithm to determine the optimal bar shape. MATERIAL AND METHODS The normal sterno-vertebral distance was defined on computed tomography (CT) scans of patients without pectus excavatum (PEx) at the same level where the deepest depression was found on CT scans of 97 patients with PEx. Four points were marked on the CT scan of 60 patients with PEx at the deepest deformity: P1: edge of the vertebra; P2: edge of the deformity; P3: the expected contact point of the bar and the rib; and P4: the expected end of the bar. The algorithm generated 3 circles upon these points, and the fusion of the arcs drew the line of the ideal bar. Corrected and normal sterno-vertebral distance values were compared with the Mann-Whitney U test. Ten bars were bent manually guided by a 1: 1 printout of the designed bar and were implanted in 10 adolescents. RESULTS The shortest sterno-vertebral distance was 3 cm below the intermammillary line in PEx patients. The normal mean sterno-vertebral distance at this level was 10.16±1.35 cm in non-PEx patients. The mean virtually corrected sterno-vertebral distance was 10.28±1.27 cm. No significant difference was found (P=0.44). The bars were seamless and were successfully implanted. No bar needed adjustment, the operation time was shorter, and the patient satisfaction score was 9.4/10. CONCLUSIONS With our new algorithm, an optimal Nuss bar can be designed.
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Algoritmos , Diseño Asistido por Computadora , Tórax en Embudo , Tomografía Computarizada por Rayos X , Humanos , Tórax en Embudo/cirugía , Tórax en Embudo/diagnóstico por imagen , Adolescente , Masculino , Femenino , Tomografía Computarizada por Rayos X/métodos , Niño , Esternón/diagnóstico por imagenRESUMEN
In this work, the effects of femtosecond laser irradiation and doping with plasmonic gold nanorods on the degree of conversion (DC) of a urethane dimethacrylate (UDMA)-triethylene glycol dimethacrylate (TEGDMA) nanocomposite were investigated. The UDMA-TEGDMA photopolymer was prepared in a 3:1 weight ratio and doped with dodecanethiol- (DDT) capped gold nanorods of 25 × 75 or 25 × 85 nm nominal diameter and length. It was found that the presence of the gold nanorods alone (without direct plasmonic excitation) can increase the DC of the photopolymer by 6-15%. This increase was found to be similar to what could be achieved with a control heat treatment of 30 min at 180 °C. It was also shown that femtosecond laser impulses (795 nm, 5 mJ pulse energy, 50 fs pulse length, 2.83 Jcm-2 fluence), applied after the photopolymerization under a standard dental curing lamp, can cause a 2-7% increase in the DC of undoped samples, even after thermal pre-treatment. The best DC values (12-15% increase) were obtained with combined nanorod doping and subsequent laser irradiation close to the plasmon resonance peak of the nanorods (760-800 nm), which proves that the excited plasmon field can directly facilitate double bond breakage (without thermoplasmonic effects due to the short pulse length) and increase the crosslink density independently from the initial photopolymerization process.
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Nanocompuestos , Nanotubos , Oro , Rayos LáserRESUMEN
OBJECTIVES: Radiosynoviorthesis (RSO) is used for the treatment of inflammatory joint diseases. However, there are no long-term results published comparing it to conservative therapy. Therefore, the aim of this prospective observational study was to evaluate response rates after radionuclide therapy in patients suffering from knee osteoarthritis over a time period of 10 years. METHODS: Radionuclide therapy with intra-articular administration of colloidal 90Yttrium citrate was performed in osteoarthritic patients [Kellgren-Lawrence grades I/II (n = 69) and Kellgren-Lawrence grade III (n = 72)]. RESULTS: In patients with early-stage disease, an excellent/good response with respect to pain, joint mobility, and function was observed in 82.5% for 1 year and in 73.7% for 8 years after therapy. Responses declined to 50% at 10 years post treatment. In grade III patients, an excellent/good response was observed in 45.9%; a decline to 41.2% was observed in the first 8 years. In this group, the number of patients available for follow-up after 9 and 10 years dropped significantly from 51 patients after 8 years to only 30 patients after 9 years, and to nine patients after 10 years. As a result, these response rates were not appraisable. CONCLUSION: Long-term results of radiosynoviorthesis in knee osteoarthritis are excellent/good in many patients. The response rate depends on Kellgren-Lawrence stages, and early-stage radionuclide therapy for osteoarthritis is suggested.
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Citratos/uso terapéutico , Efectos Adversos a Largo Plazo/epidemiología , Compuestos Organometálicos/uso terapéutico , Osteoartritis de la Rodilla/complicaciones , Radiofármacos/uso terapéutico , Sinovitis/radioterapia , Adulto , Anciano , Citratos/efectos adversos , Femenino , Humanos , Efectos Adversos a Largo Plazo/etiología , Masculino , Persona de Mediana Edad , Compuestos Organometálicos/efectos adversos , Radiofármacos/efectos adversos , Sinovitis/etiologíaRESUMEN
Nowadays open field and protected vegetable cultivation practices require and use genotypes which are precisely tailored to their intended growth environments. Variability of this kind provides a rich source of material to uncover molecular mechanisms supporting the necessarily divergent physiological traits. In this study, typical field-optimized and glasshouse-cultivated cucumber F1 hybrids were investigated, and displayed slower growth ('Joker') and faster growth ('Oitol') in seedlings. Antioxidant capacity was lower in 'Joker' and higher in 'Oitol', pointing to a potential redox regulation of growth. The growth response of seedlings to paraquat treatment indicated stronger oxidative stress tolerance in the fast-growing 'Oitol'. To test whether protection against nitrate-induced oxidative stress was also different, fertigation with increasing potassium nitrate content was applied. This treatment did not change growth but decreased the antioxidant capacities of both hybrids. Bioluminescence emission revealed stronger lipid peroxidation triggered by high nitrate fertigation in the leaves of 'Joker' seedlings. To explore the background of the more effective antioxidant protection of 'Oitol', levels of ascorbic acid (AsA), as well as transcriptional regulation of relevant genes of the Smirnoff-Wheeler biosynthetic pathway and ascorbate recycling, were investigated. Genes related to AsA biosynthesis were strongly upregulated at an elevated nitrate supply in 'Oitol' leaves only, but this was only reflected in a small increase in total AsA content. High nitrate provision also triggered expression of ascorbate-glutathion cycle genes with stronger or exclusive induction in 'Oitol'. AsA/dehydro-ascorbate ratios were higher in 'Oitol' for all treatments, with a more pronounced difference at high nitrate levels. Despite strong transcriptional upregulation of ascorbate peroxidase genes (APX) in 'Oitol', APX activity only increased significantly in 'Joker'. This suggests potential inhibition of APX enzyme activity specifically in 'Oitol' at a high nitrate supply. Our results uncover an unexpected variability in redox stress management in cucumbers, including nitrate inducibility of AsA biosynthetic and recycling pathways in certain genotypes. Possible connections between AsA biosynthesis, recycling and nitro-oxidative stress protection are discussed. Cucumber hybrids emerge as an excellent model system for studying the regulation of AsA metabolism and the roles of AsA in growth and stress tolerance.
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The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, 10 sediment cores (length 1 m) of 10 lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5-10-mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, and Zn, as well as of organochlorine pesticides (OCPs), i.e., dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH), were analyzed. A miniaturized solid-liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was used for the latter. The progression of TE concentrations over time is uniform. It follows a trans-regional pattern and is indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Of OCPs, only transformation products of DDT were found. Congener ratios indicate a mainly aerial input. In the lakes' profiles, several regional features and responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and to check for the efficiency of pollution countermeasures in the past.
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Hidrocarburos Clorados , Plaguicidas , Contaminantes Químicos del Agua , DDT/análisis , Lagos/análisis , Efectos Antropogénicos , Disentimientos y Disputas , Contaminantes Químicos del Agua/análisis , Plaguicidas/análisis , Hidrocarburos Clorados/análisis , Sedimentos Geológicos/química , Monitoreo del Ambiente/métodos , ChinaRESUMEN
Recent validation experiments on laser irradiation of polymer foils with and without implanted golden nanoparticles are discussed. First we analyze characteristics of craters, formed in the target after its interaction with the laser beam. Preliminary experimental results show significant production of deuterons when both the energy of laser pulse and concentration of nanoparticles are high enough. We consider the deuteron production via the nuclear transmutation reactions p+Câd+X where protons are accelerated by the Coulomb field generated in the target plasma. We argue that maximal proton energy can be above threshold values for these reactions and the deuteron yield may noticeably increase due to presence of nanoparticles.
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Cold-acclimated and non-acclimated contrasting Camelina (Camelina sativa L.) biotypes were investigated for changes in stress-associated biomarkers, including antioxidant enzyme activity, lipid peroxidation, protein, and proline content. In addition, a well-known freezing tolerance pathway participant known as C-repeat/DRE-binding factors (CBFs), an inducer of CBF expression (ICE1), and a cold-regulated (COR6.6) genes of the ICE-CBF-COR pathway were studied at the transcriptional level on the doubled-haploid (DH) lines. Freezing stress had significant effects on all studied parameters. The cold-acclimated DH34 (a freezing-tolerant line) showed an overall better performance under freezing stress than non-acclimated plants. The non-cold-acclimated DH08 (a frost-sensitive line) showed the highest electrolyte leakage after freezing stress. The highest activity of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase) was also detected in non-acclimated plants, whereas the cold-acclimated plants showed lower enzyme activities upon stress treatment. Cold acclimation had a significantly positive effect on the total protein and proline content of stressed plants. The qRT-PCR analysis revealed significant differences in the expression and cold-inducibility of CsCBF1-3, CsICE1, and CsCOR6.6 genes among the samples of different treatments. The highest expression of all CBF genes was recorded in the non-acclimated frost-tolerant biotype after freezing stress. Interestingly a significantly higher expression of COR6.6 was detected in cold-acclimated samples of both frost-sensitive and -tolerant biotypes after freezing stress. The presented results provide more insights into freezing tolerance mechanisms in the Camelina plant from both a biochemical point of view and the expression of the associated genes.
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The effect of heat treatment on dried fruiting bodies of Reishi medicinal mushroom (Ganoderma lingzhi) is investigated. Control and samples treated for 20 min at temperatures of 70, 120, 150 and 180 °C were subjected for their free radical scavenging capacity, different glucans and total phenolic content determination. The growth rate of Escherichia coli and Lactobacillus casei supplemented with control and heat-treated samples is also investigated. The roasted mushroom samples at 150 °C and 180 °C showed the highest level of ß-glucan (37.82%) and free radical scavenging capacity on 2,2-diphenyl-1-picrylhidrazyl (DPPHâ¢) and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTSâ¢+). The content of total phenolics (TPC) was also influenced by heat treatment and significantly higher TPC values were recorded in samples treated at 120 °C and 150 °C. The presence of reducing sugars was only detected after heat treatment at 150 °C (0.23%) and at 180 °C (0.57%). The heat treatments at 120, 150 and 180 °C, significantly attenuated the number of colony-forming units (CFU) of pathogenic E. coli, in a linear relationship with an elevated temperature. The supplementation of heat-treated Reishi mushroom at 120 °C resulted in the highest growth rate of probiotic L. casei. The obtained results in this study revealed the significant effect of short-term heat treatment by enhancing the antioxidant capacity, ß-glucan solubility and prebiotic property of the dried basidiocarp of Reishi mushroom.
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Összefoglaló. A Vibrant Soundbridge aktív középfül-implantátum vezetéses, sensorineuralis és kevert típusú halláscsökkenés esetén is megoldást jelenthet a beteg hallásrehabilitációja során. Sensorineuralis halláscsökkenés esetén akkor indikálható, ha a légvezetéses hallásküszöb nem haladja meg a 80-85 dBHL-t a 3-4 kHz frekvenciákon, vezetéses, illetve kevert típusú halláscsökkenés esetén pedig akkor, ha a csontvezetéses hallásküszöb nem haladja meg a 45-65 dBHL-t a 0,5-4 kHz közti frekvenciatartományban. Az implantátum beültetését eleinte tisztán sensorineuralis halláscsökkenés esetén végezték, és csupán egyféleképpen történhetett: a rezgéskelto rendszer oldalán lévo rögzítocsipeszt rá kellett applikálni az incus hosszú nyújtványára. Azokra az esetekre, amikor a rezgéskelto rögzítése nem kivitelezheto, különbözo rögzítoelemeket (coupler) fejlesztettek ki. Az incusra való rögzítés hosszúnyújtvány-couplerrel, illetve rövidnyújtvány-couplerrel lehetséges. Vezetéses és kevert típusú halláscsökkenés esetén a kerek ablak membránjához is illesztheto a rendszer, elorehaladott otosclerosis esetén pedig a Soundbridge-implantáció stapedotomiával kiegészített változata ("power stapes") hozhat kielégíto halláseredményt. Ezek a technikák meglehetosen megnövelték a sebész szabadságát, így széles körben alkalmazott, megbízható megoldássá váltak. A Pécsi Tudományegyetem Fül-Orr-Gégészeti és Fej-Nyaksebészeti Klinikáján az elmúlt évtizedben számos incusvibroplastica történt, de kerekablak-vibroplasticára is több alkalommal sor került. A jelen összefoglaló tanulmányban a Vibrant Soundbridge implantátum technikai fejlodésének történeti áttekintésén felül az alkalmazható mutéti megoldásokat mutatjuk be. Orv Hetil. 2021; 162(40): 1619-1626. Summary. The Vibrant Soundbridge active middle ear implant can provide a reliable solution for hearing rehabilitation of patients with conductive, sensorineural or mixed hearing loss. For sensorineural hearing loss, the air conduction threshold of the patient should not be more increased than 80-85 dBHL at the range of 3-4 kHz, and for conductive and mixed hearing loss, the bone conduction threshold should not be more increased than 45-65 dBHL between 0.5 and 4 kHz. The standard surgical procedure was originally designed for purely sensorineural hearing loss, and the fixation clip of the vibrating transducer needed to be crimped onto the long process of the incus. In many cases, it is impossible to crimp the vibrator onto the incus. In order to solve such circumstances, fixation clips (couplers) have been developed. There are two options to crimp the device on the incus: applying a long process coupler or a short process coupler. For conductive or mixed hearing loss, a round window soft coupler has been introduced. In advanced otosclerotic cases, a special combined technique of Soundbridge implantation with simultaneous stapedotomy can result in sufficient hearing rehabilitation. These techniques significantly broadened the scale of possibilities for the implantation, therefore, it became a widely utilized, reliable procedure. At the Department of Otorhino-laryngology, Clinical Center, University of Pécs, in addition to a noteworthy amount of incus vibroplasty, several cases of round window vibroplasty have also been performed. The aim of the present study is to summarize the history of development of the Vibrant Soundbridge and to present an overview of the applicable surgical techniques. Orv Hetil. 2021; 162(40): 1619-1626.
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Prótesis Osicular , Cirugía del Estribo , Audición , Humanos , Ventana Redonda , EstriboRESUMEN
Probiotic L. acidophilus La-14 cells were co-encapsulated with Ganoderma lingzhi extract to prolong the viability of the cells under simulated gastrointestinal (SGI) condition and to protect the active ingredients of Reishi mushroom during the storage period. Combinations of distinctive reagents (sodium alginate, chitosan, maltose, Hydroxyethyl-cellulose (HEC), hydroxypropyl methylcellulose (HPMC), and calcium lactate) were tested. Optimal double layer Ca-alginate hydrogel beads were fabricated with significantly improved characteristics. The incorporation of maltose significantly decreases the release rate of mushrooms' phenolics, antioxidants, and ß-glucan during the storage time. Significant improvement in probiotic cells viability under SGI condition has been found and confirmed by confocal laser microscopy in maltose containing double layer coated calcium alginate beads variants. The encapsulation of newly formulated prebiotic Reishi extract and probiotic L. acidophilus is creating a new potential food application for such medicinal mushrooms and natural products with unpleasant taste upon oral consumption.
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Agaricales/química , Alginatos/química , Productos Biológicos/química , Ganoderma/química , Lactobacillus acidophilus/química , Probióticos/química , Antioxidantes/química , Antioxidantes/farmacología , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Fraccionamiento Químico/métodos , Fenómenos Químicos , Composición de Medicamentos/métodos , Glucosa/química , Metilcelulosa/química , beta-Glucanos/químicaRESUMEN
Silicon (Si) is a ubiquitous element in soil with well-known beneficial effects under certain conditions, in several plant species, if supplied in available form for uptake. It may alleviate damage in various stress situations and may also promote growth when no obvious stressors are applied. Effects of Si are often linked to mitigation of oxidative stress, in particular to the induction of antioxidant defense mechanisms. In the work presented, the impact of silicon provision on pro-oxidant systems was investigated in cucumber. Plants of the F1 cultivar hybrid 'Joker' were grown under in vitro conditions in the absence of any applied external stressor. Silicon provision decreased H2O2 content and lowered lipid peroxidation in the leaves of the treated plants. This was paralleled by declining polyamine oxidase (PAO) and diamine oxidase (DAO) activities. Several PAO as well as lipoxygenase (LOX) genes were coordinately downregulated in Si-treated plants. Unlike in similar systems studied earlier, the Si effect was not associated with an increased transcript level of gene coding for antioxidant enzymes. These results suggest an inhibitory effect of Si provision on pro-oxidant amine oxidases, which may decrease the level of reactive oxygen species by retarding their production. This extends the molecular mechanisms linked to silicon effects onto redox balance in plants.
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⢠The staygreen (SGR) gene encodes a chloroplast-targeted protein which promotes chlorophyll degradation via disruption of light-harvesting complexes (LHCs). ⢠Over-expression of SGR in Arabidopsis (SGR-OX) in a Columbia-0 (Col-0) background caused spontaneous necrotic flecking. To relate this to the hypersensitive response (HR), Col-0, SGR-OX and RNAi SGR (SGRi) lines were challenged with Pseudomonas syringae pv tomato (Pst) encoding the avirulence gene avrRpm1. Increased and decreased SGR expression, respectively, accelerated and suppressed the kinetics of HR-cell death. In Col-0, SGR transcript increased at 6 h after inoculation (hai) when tissue electrolyte leakage indicated the initiation of cell death. ⢠Excitation of the chlorophyll catabolite pheophorbide (Pheide) leads to the formation of toxic singlet oxygen ((1)O(2)). Pheide was first detected at 6 hai with Pst avrRpm1 and was linked to (1)O(2) generation and correlated with reduced Pheide a oxygenase (PaO) protein concentrations. The maximum quantum efficiency of photosystem II (F(v)/F(m)), quantum yield of electron transfer at photosystem II (φPSII), and photochemical quenching (qP) decreased at 6 hai in Col-0 but not in SGRi. Disruption of photosynthetic electron flow will cause light-dependent H(2)O(2) generation at 6 hai. ⢠We conclude that disruption of LHCs, possibly influenced by SGR, and absence of PaO produce phototoxic chlorophyll catabolites and oxidative stress leading to the HR.
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Arabidopsis/metabolismo , Arabidopsis/microbiología , Clorofila/metabolismo , Luz , Pseudomonas syringae/fisiología , Arabidopsis/enzimología , Arabidopsis/inmunología , Proteínas de Arabidopsis/metabolismo , Muerte Celular/efectos de la radiación , Complejos de Proteína Captadores de Luz/metabolismo , Modelos Biológicos , Oxidación-Reducción/efectos de la radiación , Oxigenasas/metabolismo , Fotosíntesis/efectos de la radiación , Pseudomonas syringae/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Two cucumber F1 cultivar hybrids were investigated for stress tolerance markers upon application of different strength of Hoagland fertigation solutions (HG). 'Joker' and 'Oitol' cultivar hybrids were studied, representing typically field grown and greenhouse cultivated genotypes, respectively. At standard fertigation level (0.5â¯×â¯HG) in controlled environment young 'Joker' plants displayed slower growth than 'Oitol' based on total leaf area. At this basal nutrient concentration leaves of 'Joker' plants had significantly lower antioxidant capacity and higher malondialdehyde (MDA, an indicator of lipid peroxidation) level than 'Oitol'. According to RT-qPCR transcript levels of several antioxidant enzymes' genes (ascorbate peroxidase, glutathione reductase and glutathione peroxidase) were significantly higher in 'Joker' compared to 'Oitol'. At increased HG concentrations (1.0, 1.5, 2.0, and 2.5â¯×â¯HG) growth didn't change significantly in either hybrid. Osmotic potential declined at higher fertigation levels. Antioxidant capacity increased in both hybrids with strong characteristic differences favouring 'Oitol' plants. Higher MDA content of leaves testified more oxidative burden in 'Joker' plants at all and especially at the more concentrated HG treatments. This trend was also approved by results of bio photon emission imaging, which is a powerful method to quantify stress level in living tissues with autoluminescence detection technology. Gene expression for antioxidant enzymes followed HG concentration-dependent increase in both hybrids, at a substantially higher level in 'Joker'. Expression of the dehydrin gene DHN3 was preferentially induced at elevated fertigation levels in 'Oitol' plants, which could contribute to the lower oxidative stress detected in this hybrid. Results presented in this report demonstrate differences in shoot growth, antioxidant capacity, level of oxidative stress and antioxidant gene expression in two contrasting cucumber hybrids at basal fertigation. Furthermore, excessive HG fertigation was found to increase oxidative stress in a genotype-specific way. This effect may be due to different antioxidant capacity and differential expression of stress protective genes, such as the DHN3 dehydrin.
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Cucumis sativus/genética , Expresión Génica/genética , Estrés Oxidativo/genética , Proteínas de Plantas/genética , Antioxidantes/metabolismo , Ascorbato Peroxidasas/genética , Catalasa/genética , Glutatión Peroxidasa/genética , Glutatión Reductasa/genética , Peroxidación de Lípido/genética , Malondialdehído/metabolismo , Hojas de la Planta/genética , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/genéticaRESUMEN
The Internet on the router level, is a complex network embedded in a geographical space. We provide experimental evidences suggesting that the average travel time for a message, with fixed length, increases roughly as the square root of the geographical distance. To understand this scaling law and other measurable topological properties of the Internet as a graph, we introduce and study a simple network model. The model is based on a few realistic socio-economic facts/assumptions and qualitatively reproduces the experimentally observed stylized facts.
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The main drawback of minimum variance distortionless response (MVDR) beamformer is the cancellation of the desired speech signal and its degradation in multi-path wave propagation environment. To make the adaptive algorithm robust against room reverberation and to prevent desired signal cancellation an estimation of unknown desired speaker's transfer function was proposed. The estimation is based on the signal and the interference covariance matrices. The estimated transfer function is then applied to the MVDR beamformer. The proposed algorithm was tested on a simulated room with reverberation. The results showed better quality of the restored speech compared to some typical adaptive algorithms.
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Audición/fisiología , Habla , Acústica , Algoritmos , Humanos , Modelos TeóricosRESUMEN
Given a network, the statistical ensemble of its graph-Voronoi diagrams with randomly chosen cell centers exhibits properties convertible into information on the network's large scale structures. We define a node-pair level measure called Voronoi cohesion which describes the probability for sharing the same Voronoi cell, when randomly choosing g centers in the network. This measure provides information based on the global context (the network in its entirety), a type of information that is not carried by other similarity measures. We explore the mathematical background of this phenomenon and several of its potential applications. A special focus is laid on the possibilities and limitations pertaining to the exploitation of the phenomenon for community detection purposes.
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OBJECTIVE: Insomnia complaints are frequent among kidney transplant (kTx) recipients and are associated with fatigue, depression, lower quality of life and increased morbidity. However, it is not known if subjective insomnia symptoms are associated with objective parameters of sleep architecture. Thus, we analyze the association between sleep macrostructure and EEG activity versus insomnia symptoms among kTx recipients. METHODS: Participants (n1=100) were selected from prevalent adult transplant recipients (n0=1214) followed at a single institution. Insomnia symptoms were assessed by the Athens Insomnia Scale (AIS) and standard overnight polysomnography was performed. In a subgroup of patients (n2=56) sleep microstructure was also analyzed with power spectral analysis. RESULTS: In univariable analysis AIS score was not associated with sleep macrostructure parameters (sleep latency, total sleep time, slow wave sleep, wake after sleep onset), nor with NREM and REM beta or delta activity in sleep microstructure. In multivariable analysis after controlling for covariables AIS score was independently associated with the proportion of slow wave sleep (ß=0.263; CI: 0.026-0.500) and REM beta activity (ß=0.323; CI=0.041-0.606) (p<0.05 for both associations). CONCLUSIONS: Among kTx recipients the severity of insomnia symptoms is independently associated with higher proportion of slow wave sleep and increased beta activity during REM sleep but not with other parameters sleep architecture. The results suggest a potential compensatory sleep protective mechanism and a sign of REM sleep instability associated with insomnia symptoms among this population.
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Trasplante de Riñón/efectos adversos , Polisomnografía/métodos , Calidad de Vida/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/etiología , Femenino , Humanos , Trasplante de Riñón/psicología , Masculino , Persona de Mediana EdadRESUMEN
The average travelling speed increases in a nontrivial manner with the travel distance. This leads to scaling-like relations on quite extended spatial scales, for all mobility modes taken together and also for a given mobility mode in part. We offer a wide range of experimental results, investigating and quantifying this universal effect and its measurable causes. The increasing travelling speed with the travel distance arises from the combined effects of: choosing the most appropriate travelling mode; the structure of the travel networks; the travel times lost in the main hubs, starting or target cities; and the speed limit of roads and vehicles.
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Viaje , Toma de Decisiones , Sistemas de Información Geográfica , Humanos , Hungría , Conceptos Matemáticos , Modelos Teóricos , Factores de Tiempo , Transportes/métodos , Viaje/psicología , Estados UnidosRESUMEN
The 'nuclear side' of RNA interference (RNAi) is increasingly recognized as an integral part of RNA-mediated gene silencing networks. Current data are consistent with the idea that epigenetic changes, such as DNA (cytosine-5) methylation and histone modifications, can be targeted to identical DNA sequences by short RNAs derived via Dicer cleavage of double-stranded RNA (dsRNA). To determine the relationships among RNA signals, DNA methylation and chromatin structure, we are carrying out a genetic analysis of RNA-mediated transcriptional gene silencing (TGS) in Arabidopsis. Results obtained so far indicate that in response to RNA signals, different site-specific DNA methyltransferases (DMTases) cooperate with each other and eventually with histone-modifying enzymes to establish and maintain a transcriptionally inactive state at a homologous target promoter. Processing of dsRNA in Arabidopsis occurs in the nucleus and in the cytoplasm, where distinct Dicer-like (DCL) activities are thought to generate functionally distinct classes of short RNAs. RNA silencing pathways thus operate throughout the cell to defend against invasive nucleic acids and to regulate genome structure and function.