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Here, starch derivatives, i.e., sodium starch octenylsuccinate (OSA starch, hereinafter referred to as OSA), were employed as both reducing and stabilizing agents for the unique, inexpensive, and simple synthesis of gold nanoparticles (OSA-AuNPs) in an aqueous solution with gold salt. The obtained OSA-AuNPs were characterized by UV-vis spectrophotometry, transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The catalytic activity of the obtained gold colloids was studied in the reduction of organic dyes, including methylene blue (C.I. Basic Blue 9) and rhodamine B (C.I. Basic Violet 10), and food coloring, including tartrazine (E102) and azorubine (E122), by sodium borohydride. Moreover, OSA-AuNPs were utilized as signal amplifiers in surface-enhanced Raman spectroscopy. The obtained results confirmed that gold nanoparticles can be used as effective catalysts in reduction reactions of selected organic dyes, as well as signal enhancers in the SERS technique.
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Oro , Nanopartículas del Metal , Almidón , Oro/química , Nanopartículas del Metal/química , Catálisis , Almidón/química , Espectrometría Raman , Succinatos/química , Oxidación-ReducciónRESUMEN
The research was based on a field experiment carried out in the Agricultural Experimental Station in the climatic and soil conditions of north-eastern Poland. The factors of the experiment were: I-morphotypes of winter oilseed rape: population, restored hybrid with a traditional type of growth, restored hybrid with a semi-dwarf type of growth. II-methods of using preparations: variant (1)-control-without using preparations; variant (2)-an organic preparation containing microorganisms as well as micro and macro elements (Ugmax); variant (3)-a biostimulant containing 13.0% of P205 and 5.0% of potassium oxide (K2O); variant (4)-a biostimulant containing silicon. The objectives of study was to determine the effect of preparations containing microorganisms as this well as micro and macro-elements, phosphorus and potassium and silicon on the morphometric features of plants, such as: the height of the first fruit-bearing lateral branching on the main shoot, the thickness of the stem at the base, number of productive branches and siliques on the plant, the length of the pods, plant height before harvesting. The organic preparation containing microorganisms as well as micro and macro-elements, applied in the autumn before sowing seeds and in the spring after the start of vegetation, had the most beneficial effect on the biometric characteristics of plants before harvesting.
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Brassica napus , Brassica rapa , Suelo , Polonia , Silicio , BiometríaRESUMEN
Spatio-temporal gradients in thermal and oxygen conditions trigger evolutionary and developmental responses in ectotherms' body size and cell size, which are commonly interpreted as adaptive. However, the evidence for cell-size responses is fragmentary, as cell size is typically assessed in single tissues. In a laboratory experiment, we raised genotypes of Drosophila melanogaster at all combinations of two temperatures (16 °C or 25 °C) and two oxygen levels (10% or 22%) and measured body size and the sizes of cells in different tissues. For each sex, we measured epidermal cells in a wing and a leg and ommatidial cells of an eye. For males, we also measured epithelial cells of a Malpighian tubule and muscle cells of a flight muscle. On average, females emerged at a larger body size than did males, having larger cells in all tissues. Flies of either sex emerged at a smaller body size when raised under warm or hypoxic conditions. Development at 25 °C resulted in smaller cells in most tissues. Development under hypoxia resulted in smaller cells in some tissues, especially among females. Altogether, our results show thermal and oxygen conditions trigger shifts in adult size, coupled with the systemic orchestration of cell sizes throughout the body of a fly. The nature of these patterns supports a model in which an ectotherm adjusts its life-history traits and cellular composition to prevent severe hypoxia at the cellular level. However, our results revealed some inconsistencies linked to sex, cell type, and environmental parameters, which suggest caution in translating information obtained for single type of cells to the organism as a whole.
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Along with different life strategies, organisms have evolved dramatic cellular composition differences. Understanding the molecular basis and fitness effects of these differences is key to elucidating the fundamental characteristics of life. TOR/insulin pathways are key regulators of cell size, but whether their activity determines cell size in a systemic or tissue-specific manner awaits exploration. To that end, we measured cells in four tissues in genetically modified Drosophila melanogaster (rictorΔ2 and Mnt1) and corresponding controls. While rictorΔ2 flies lacked the Rictor protein in TOR complex 2, downregulating the functions of this element in TOR/insulin pathways, Mnt1 flies lacked the transcriptional regulator protein Mnt, weakening the suppression of downstream signalling from TOR/insulin pathways. rictorΔ2 flies had smaller epidermal (leg and wing) and ommatidial cells and Mnt1 flies had larger cells in these tissues than the controls. Females had consistently larger cells than males in the three tissue types. In contrast, dorsal longitudinal flight muscle cells (measured only in males) were not altered by mutations. We suggest that mutations in cell cycle control pathways drive the evolution of systemic changes in cell size throughout the body, but additional mechanisms shape the cellular composition of some tissues independent of these mutations.
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Drosophila melanogaster , Insulinas , Femenino , Masculino , Animales , Drosophila melanogaster/genética , Mutación , Tamaño de la Célula , Factores de Transcripción/genética , Ciclo CelularRESUMEN
Along with differences in life histories, metazoans have also evolved vast differences in cellularity, involving changes in the molecular pathways controlling the cell cycle. The extent to which the signalling network systemically determines cellular composition throughout the body and whether tissue cellularity is organized locally to match tissue-specific functions are unclear. We cultured genetic lines of Drosophila melanogaster on food with and without rapamycin to manipulate the activity of target of rapamycin (TOR)/insulin pathways and evaluate cell-size changes in five types of adult cells: wing and leg epidermal cells, ommatidial cells, indirect flight muscle cells and Malpighian tubule epithelial cells. Rapamycin blocks TOR multiprotein complex 1, reducing cell growth, but this effect has been studied in single cell types. As adults, rapamycin-treated flies had smaller bodies and consistently smaller cells in all tissues. Regardless, females eclosed with larger bodies and larger cells in all tissues than males. Thus, differences in TOR activity and sex were associated with the orchestration of cell size throughout the body, leading to differences in body size. We postulate that the activity of TOR/insulin pathways and their effects on cellularity should be considered when investigating the origin of ecological and evolutionary patterns in life histories.
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Proteínas de Drosophila , Insulinas , Animales , Masculino , Femenino , Drosophila melanogaster/genética , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Sirolimus/farmacología , Sirolimus/metabolismo , Tamaño de la Célula , Insulinas/metabolismo , Tamaño CorporalRESUMEN
BACKGROUND: Pelvic asymmetry and accompanying postural defects tend to become more common with age. The school period, which is associated with spending more time in a sitting position and daily activities performed with the dominant limb, may contribute to this. MATERIAL AND METHODS: We examined 22 children (12 girls, 10 boys) aged 7 years. The same group was re-examined two years later. Pelvic asymmetry was identified by assessing the position of the iliac spines. The indicator of trunk asymmetry was the trunk rotation angle (TRA) measured with a Bunnel scoliometer within the spinous processes on the upper thoracic vertebra, apex of thoracic kyphosis, thoracolumbar junction, lumbar spine, and (if present in patients) the greatest deformity (rib hump, hump in the lumbar region). RESULTS: Pelvic asymmetry was detected in 14 children at the age of 7 years compared to 16 in the same group of patients aged 9 years. During these two years, the prevalence of trunk asymmetry in children with an oblique/rotated pelvis had increased. The progression of trunk asymmetry with an oblique position of the pelvis was most marked in the lumbar region. In children with symmetrical pelvis, the most marked increase in TRA was recorded in the thoracic segment. CONCLUSIONS: 1. The development of pelvic girdle asymmetry is influenced by the increasing number of asymmetrically performed movements and asymmetric body positions assumed, which increase in number with age. 2. The most marked increase in asymmetry of the spine in subjects with an oblique/rotated pelvis was seen in the lumbar spine, which proves an association of the former with tilting of the pelvic girdle. 3. Asymmetry is a dynamic process. When ignored, this postural defect progresses significantly and there may be compensatory changes in neighbouring systems.
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Vértebras Lumbares , Escoliosis , Masculino , Femenino , Humanos , Niño , Vértebras Torácicas , Movimiento , Postura , PelvisRESUMEN
The study was based on in 2016-2017, 2017-2018, 2018-2019 field experiment conducted at the University of Natural Sciences and Humanities in Siedlce (Zawady Agricultural Experimental Station), eastern Poland. The studied factors were: I. winter rape cultivars: Monolit-open pollinated cultivar; PT248-F1 hybrid cultivars with traditional growth type; PX115-F1 hybrid cultivars with a semi-dwarf growth type and types of foliar nutrition: (1) control variant without foliar nutrition and amino acids; (2) amino acid; (3) foliar fertilizer sulphur and boron; (4) foliar fertilizer sulphur with foliar fertilizer boron and amino acid. The aim of the study was to determine the effect of foliar application of sulphur, boron, amino acids on the use and feed value of seeds of three winter rape morphotypes. The highest content of crude fat in seeds of the studied morphotypes was found after foliar fertilization with sulphur and boron and amino acids, while the lowest under the influence of amino acids. The highest concentration of total protein was obtained after the application of amino acids, and regardless of the morphotype studied on this object, the same value of this trait was demonstrated. In restored morphotypes, the use of additional foliar fertilization S and B in combination with amino acids did not significantly increase this characteristic compared to the amino acid variant. As a result of the application of amino acids and foliar feeding of S and B, and amino acids, the largest increase in crude fibre content in rapeseeds was obtained, while the application of S and B did not significantly increase this characteristic compared to the control variant. The best feed and use value of seeds were noted in restored morphotypes, with the semi-dwarf variety having the highest fat and crude fibre content. Climatic conditions in the years of research significantly determined the value of seeds. The highest values of the examined traits were obtained in the last year of the study, and the lowest in the growing season 2016-2017.
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Alterations in cell number and size are apparently associated with the body mass differences between species and sexes, but we rarely know which of the two mechanisms underlies the observed variance in body mass. We used phylogenetically informed comparisons of males and females of 19 Carabidae beetle species to compare body mass, resting metabolic rate, and cell size in the ommatidia and Malpighian tubules. We found that the larger species or larger sex (males or females, depending on the species) consistently possessed larger cells in the two tissues, indicating organism-wide coordination of cell size changes in different tissues and the contribution of these changes to the origin of evolutionary and sex differences in body mass. The species or sex with larger cells also exhibited lower mass-specific metabolic rates, and the interspecific mass scaling of metabolism was negatively allometric, indicating that large beetles with larger cells spent relatively less energy on maintenance than small beetles. These outcomes also support existing hypotheses about the fitness consequences of cell size changes, postulating that the low surface-to-volume ratio of large cells helps decrease the energetic demand of maintaining ionic gradients across cell membranes. Analyses with and without phylogenetic information yielded similar results, indicating that the observed patterns were not biased by shared ancestry. Overall, we suggest that natural selection does not operate on each trait independently and that the linkages between concerted cell size changes in different tissues, body mass and metabolic rate should thus be viewed as outcomes of correlational selection.
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Metabolismo Basal , Evolución Biológica , Tamaño Corporal , Tamaño de la Célula , Escarabajos , Animales , Escarabajos/crecimiento & desarrollo , Escarabajos/metabolismo , Escarabajos/fisiología , Caracteres SexualesRESUMEN
During development, cells may adjust their size to balance between the tissue metabolic demand and the oxygen and resource supply: Small cells may effectively absorb oxygen and nutrients, but the relatively large area of the plasma membrane requires costly maintenance. Consequently, warm and hypoxic environments should favor ectotherms with small cells to meet increased metabolic demand by oxygen supply. To test these predictions, we compared cell size (hindgut epithelium, hepatopancreas B cells, ommatidia) in common rough woodlice (Porcellio scaber) that were developed under four developmental conditions designated by two temperatures (15 or 22°C) and two air O2 concentrations (10% or 22%). To test whether small-cell woodlice cope better under increased metabolic demand, the CO2 production of each woodlouse was measured under cold, normoxic conditions and under warm, hypoxic conditions, and the magnitude of metabolic increase (MMI) was calculated. Cell sizes were highly intercorrelated, indicative of organism-wide mechanisms of cell cycle control. Cell size differences among woodlice were largely linked with body size changes (larger cells in larger woodlice) and to a lesser degree with oxygen conditions (development of smaller cells under hypoxia), but not with temperature. Developmental conditions did not affect MMI, and contrary to predictions, large woodlice with large cells showed higher MMI than small woodlice with small cells. We also observed complex patterns of sexual difference in the size of hepatopancreatic cells and the size and number of ommatidia, which are indicative of sex differences in reproductive biology. We conclude that existing theories about the adaptiveness of cell size do not satisfactorily explain the patterns in cell size and metabolic performance observed here in P. scaber. Thus, future studies addressing physiological effects of cell size variance should simultaneously consider different organismal elements that can be involved in sustaining the metabolic demands of tissue, such as the characteristics of gas-exchange organs and O2-binding proteins.
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INTRODUCTION: Polycythemia vera (PV) is a rare myeloproliferative disease associated with an increased prevalence of hypertension and increased risk of cardiovascular complications. However, the precise mechanisms leading to the elevation of blood pressure (BP) and secondary target organ damage remain poorly understood. OBJECTIVES: The study aimed to evaluate BP profile, assess the activity of the sympathetic nervous system and the reninangiotensin system, and provide a comprehensive assessment of subclinical target organ damage in patients with PV. PATIENTS AND METHODS: Twenty consecutive patients with newly diagnosed PV and 20 control subjects were included. The following were assessed: BP, levels of catecholamines, urinary and plasma Omethylated catecholamine metabolites, concentrations of aldosterone and renin. We also assessed microneurography sympathetic nervous system activity (MSNA) and baroreflex control of heart rate as well as subclinical target organ damage. RESULTS: At similar levels of BP, BP variability was decreased in the PV group (mean [SD] 24hour systolic BP, 9 [3] vs 12 [3] mm Hg; P = 0.003). Patients with PV had lower norepinephrine excretion (mean [SD], 16.54 [6.32] vs 25.46 [12.88] µg/d; P = 0.03) as well as decreased MSNA as assessed by microneurography compared with controls (mean [SD] MSNA, 30.7 [8.7] bursts/min vs 38.7 [5.4] bursts/min; P = 0.007 and MSNA 51.8 [11] bursts/100 beats vs 61.1 [11.3] bursts/100 heart beats; P = 0.04). Baroreflex control of HR was unaltered in the PV group. Increased hemoglobin levels and red blood cell count correlated with decreased retinal capillary flow in patients with PV. CONCLUSIONS: Patients with PV, characterized by high hemoglobin concentrations and hematocrit levels had lower sympathetic nervous activity and decreased BP variability as compared with controls. There was no relationship between hemoglobin plasma concentration, hematocrit level, and target organ damage.
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Hipertensión , Policitemia Vera , Barorreflejo , Presión Sanguínea , Humanos , Policitemia Vera/complicaciones , Sistema Nervioso SimpáticoRESUMEN
Climate impact studies regarding floods usually focus on peak discharges and a bivariate assessment of peak discharges and hydrograph volumes is not commonly included. A joint consideration of peak discharges and hydrograph volumes, however, is crucial when assessing flood risks for current and future climate conditions. Here, we present a methodology to develop synthetic design hydrographs for future climate conditions that jointly consider peak discharges and hydrograph volumes. First, change factors are derived based on a regional climate model and are applied to observed precipitation and temperature time series. Second, the modified time series are fed into a calibrated hydrological model to simulate runoff time series for future conditions. Third, these time series are used to construct synthetic design hydrographs. The bivariate flood frequency analysis used in the construction of synthetic design hydrographs takes into account the dependence between peak discharges and hydrograph volumes, and represents the shape of the hydrograph. The latter is modeled using a probability density function while the dependence between the design variables peak discharge and hydrograph volume is modeled using a copula. We applied this approach to a set of eight mountainous catchments in Switzerland to construct catchment-specific and season-specific design hydrographs for a control and three scenario climates. Our work demonstrates that projected climate changes have an impact not only on peak discharges but also on hydrograph volumes and on hydrograph shapes both at an annual and at a seasonal scale. These changes are not necessarily proportional which implies that climate impact assessments on future floods should consider more flood characteristics than just flood peaks.
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Cell size plays a role in evolutionary and phenotypically plastic changes in body size. To examine this role, we measured the sizes of seven cell types of geckos (Paroedura picta) reared at three constant temperatures (24, 27, and 30°C). Our results show that the cell size varies according to the body size, sex and developmental temperature, but the pattern of this variance depends on the cell type. We identified three groups of cell types, and the cell sizes changed in a coordinated manner within each group. Larger geckos had larger erythrocytes, striated muscle cells and hepatocytes (our first cell group), but their renal proximal tubule cells and duodenal enterocytes (our second cell group), as well as tracheal chondrocytes and epithelial skin cells (our third cell group), were largely unrelated to the body size. For six cell types, we also measured the nuclei and found that larger cells had larger nuclei. The relative sizes of the nuclei were not invariant but varied in a complex manner with temperature and sex. In conclusion, we provide evidence suggesting that changes in cell size might be commonly involved in the origin of thermal and sexual differences in adult size. A recent theory predicts that smaller cells speed up metabolism but demand more energy for their maintenance; consequently, the cell size matches the metabolic demand and supply, which in ectotherms, largely depends on the thermal conditions. The complex thermal dependency of cell size in geckos suggests that further advancements in understanding the adaptive value of cell size requires the consideration of tissue-specific demand/supply conditions.
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Various commercial dextrins were used as reducing and stabilizing agents for a novel one-step synthesis of silver nanoparticles from ammonia complexes of silver ions. As a result, stable colloids of silver were formed during the reaction with the particle size being the function of the dextrin type. The obtained colloids were characterized by UV-vis spectrophotometry, size distribution (using Non-Invasive Backscatter optics) and transmission electron microscopy (TEM). The achieved results clearly indicate the possibility of low-cost production of large quantities of colloidal silver nanoparticles using materials derived from renewable sources. The resulting silver colloids can be used for different purposes, e.g. as bactericidal agents. Combination of the aforementioned properties of nanosilver particles with plasticizing properties of dextrin enables to obtain cement mortars with increased workability and enhanced compressive strength. Moreover, the obtained material is also characterized by increased immunity to adverse impact of microorganisms.
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Materiales de Construcción , Nanopartículas del Metal/química , Plata/química , Técnicas de Química Sintética , Coloides , Fuerza Compresiva , Tamaño de la PartículaRESUMEN
We report a novel room-temperature synthesis of selenium nanoparticles, which for the first time uses lignosulfonate as a stabilizer. Various lignosulfonates obtained both from hardwood and softwood were tested. Selenium oxide was used as the precursor of zero-valent selenium. Three different reducers were tested - sodium borohydride, hydrazine and ascorbic acid - and the latter proved most effective in terms of the particle size and stability of the final colloid. The lignosulfonate-stabilized selenium nanoparticles had a negative zeta potential, dependent on pH, which for some lignosulfonates reached -50mV, indicating the excellent stability of the colloid. When spherical silica particles were introduced to the synthesis mixture, selenium nanoparticles were deposited on their surface. Additionally, star-like structures consisting of sharp selenium needles with silica cores were observed. After drying, the selenium-functionalized silica had a grey metallic hue. The method reported here is simple and cost-effective, and can be used for the preparation of large quantities of selenium colloids or the surface modification of other materials with selenium.
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Lignina/análogos & derivados , Nanopartículas/química , Selenio/química , Dióxido de Silicio/química , Lignina/química , Tamaño de la Partícula , Propiedades de SuperficieAsunto(s)
Policitemia Vera/sangre , Policitemia Vera/diagnóstico por imagen , Disfunción Ventricular Izquierda/sangre , Disfunción Ventricular Izquierda/diagnóstico por imagen , Anciano , Estudios Transversales , Ecocardiografía , Femenino , Hematócrito/tendencias , Humanos , Masculino , Persona de Mediana Edad , Policitemia Vera/epidemiología , Disfunción Ventricular Izquierda/epidemiologíaRESUMEN
OBJECTIVES: The epidemiology of myelodysplastic syndromes (MDS) differs among countries. Here, we present the first epidemiological indices determined for Poland. METHODS: Twenty-one haematological centres participated in the study. Patients diagnosed with MDS and acute myeloid leukaemia (AML) with 20-29% blasts were enrolled. Data collection was conducted for strictly predefined period. RESULTS: The overall crude incidence rate for all MDS subtypes was 1.95 (95% CI, 1.81-2.09) per 100 000 person-years: 2.46 (95% CI, 2.24-2.69) for males and 1.47 (95% CI, 1.31-1.65) for females; after excluding AML cases, the indices were as follows: 2.35 (95% CI, 2.08-2.66) for males and 1.27 (95% CI, 1.08-1.5) for females. Prevalence rate was 6.2 per 100 000 persons (95% CI, 5.96-6.45), that is 6.86 (95% CI, 6.49-7.24) for males and 5.58 (95% CI, 5.26-5.92) for females. Both incidence and prevalence increased with increasing age. The most frequently diagnosed MDS subtype was refractory cytopenia with multilineage dysplasia (RCMD), responsible for 30.3% of all newly diagnosed MDSs. CONCLUSIONS: RCMD is the most frequent MDS subtype in Poland. Incidence and prevalence indices are lower than those reported for other populations, which probably results from inadequate diagnosis of potential cases of this disease.
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Errores Diagnósticos , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Polonia/epidemiología , Vigilancia de la Población , Prevalencia , Factores Sexuales , Adulto JovenRESUMEN
BACKGROUND: Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal stem cell disorders characterized by ineffective hematopoiesis, cytopenias and a risk of progression to acute myeloid leukemia (AML). Anemia is the most frequent cytopenia diagnosed in patients with MDS. Regular RBC transfusions are the only treatment option for about 40% of patients. Transfusion-dependent patients develop secondary iron overload. The influence of serum ferritin (SF) concentration on survival and acute myeloid leukemia transformation in MDS patients remains controversial. The data for the Central European population is scarce and so far there is no description for Poland. OBJECTIVES: The aim of this study was to perform a retrospective analysis of the relationship of SF concentration with red blood cell transfusion dependency, survival and transformation to acute myeloid leukemia. MATERIAL AND METHODS: We retrospectively evaluated the data of the 819 MDS patients (58% male; median age 70 years) included in the MDS Registry of the MDS Section of the Polish Adult Leukemia Group (PALG). RESULTS: Analyses were performed on 190 patients diagnosed with MDS, maximal 6 months before inclusion to the registry in order to avoid selection bias (a shorter survival of higher risk MDS patients). Patients with hyperferritinemia higher than 1000 ng/L vs. patients with SF concentration lower than 1000 ng/L had a median survival of 320 days vs. 568 days, respectively (p log-rank = 0.014). The following factors were found to significantly worsen survival: RBC-transfusion dependence (p = 0.0033; HR 2.67L), platelet transfusion dependence (p = 0.0071; HR 3.321), hemoglobin concentration lower than 10 g/dL (p = 0.0036; HR 2.97), SF concentration higher than 1000 ng/L (p = 0.0023; HR = 2.94), platelet count lower than 10 G/L (p = 0.0081 HR = 5.04), acute leukemia transformation (p = 0.0081; HR 1.968). CONCLUSIONS: Taking into account the relatively low number of patients in previous studies exploring hyperferritinemia in MDS, the results of the first Polish MDS Registry provide important insights. Hyperferritinemia higher than 1000 ng/L can be an important indicator of poor prognosis in MDS.
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Transfusión de Eritrocitos/efectos adversos , Sobrecarga de Hierro/complicaciones , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/terapia , Anciano , Anciano de 80 o más Años , Femenino , Ferritinas/sangre , Humanos , Masculino , Persona de Mediana Edad , Polonia , Modelos de Riesgos Proporcionales , Sistema de Registros , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
Working memory impairments are prevalent among patients with acquired brain injury (ABI). Computerised training targeting working memory has been researched extensively using samples from healthy populations but this field remains isolated from similar research in ABI patients. We report the results of an actively controlled randomised controlled trial in which 17 patients and 18 healthy subjects completed training on an N-back task. The healthy group had superior improvements on both training tasks (SMD = 6.1 and 3.3) whereas the ABI group improved much less (SMD = 0.5 and 1.1). Neither group demonstrated transfer to untrained tasks. We conclude that computerised training facilitates improvement of specific skills rather than high-level cognition in healthy and ABI subjects alike. The acquisition of these specific skills seems to be impaired by brain injury. The most effective use of computer-based cognitive training may be to make the task resemble the targeted behaviour(s) closely in order to exploit the stimulus-specificity of learning.
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Lesiones Encefálicas/rehabilitación , Aprendizaje , Memoria a Corto Plazo , Rehabilitación Neurológica/métodos , Terapia Asistida por Computador/métodos , Transferencia de Experiencia en Psicología , Adolescente , Adulto , Lesiones Encefálicas/psicología , Estudios de Casos y Controles , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
It is shown that lignosulfonate (LS) can be used as an effective reducing agent for gold ions and simultaneously as a stabilizing agent for gold nanoparticles (AuNPs). When organically modified silica is introduced to the reaction mixture, most of the AuNPs grow on the surface of the silica due to hydrophobic interactions between LS and organic layers covering the solid particles. It was also found that the structure of the organic layer is crucial for the effective deposition of gold nanoparticles onto silica spheres in terms of particle size and gold content in the final SiO2-LS-AuNPs composites. Due to the hydrophobicity of the modified silica it was necessary to carry out the modification in mixed organic/aqueous solvent. The polarity of the organic co-solvent was found to have an effect on the size of the deposited Au-NPs and their quantity. The physical appearance of the obtained hybrids was analyzed by colorimetry, and their structure and composition were evaluated using transmission electron microscopy (TEM). Additionally dispersive and thermal properties were examined by dynamic light scattering (DLS) and thermogravimetry (TG), respectively. The obtained multifunctional hybrid materials exhibits remarkable catalytic activity for the reduction of C.I. Basic Blue 9 (Methylene Blue) by borohydride.
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Oro/química , Lignina/análogos & derivados , Nanopartículas del Metal/química , Dióxido de Silicio/química , Catálisis , Colorimetría , Lignina/química , Nanopartículas del Metal/ultraestructura , Tamaño de la Partícula , Análisis Espectral/métodos , TermogravimetríaRESUMEN
Epidemiological studies on myelodysplastic syndromes (MDS) in Middle-Eastern Europe are scarce. No data about the demographic, clinical, and laboratory features of Polish MDS patients have been published. The aim of this study was to assess the epidemiological data and toxic exposure of Polish MDS patients and their association with hematological parameters and clinical outcomes. For 15 months, 966 living MDS patients were enrolled at 24 centers (12 university and 12 community hospitals). Follow-up was conducted for the next 55 months. The percentage of patients older than 80 years (16%) was between the values for Eastern and Western countries. In patients younger than 55 years, a female predominance was observed (male/female ratio 0.70:1 vs. 1.29:1; p < 0.001). Female patients had higher platelet counts (160 × 109/l vs. 111 × 109/l; p < 0.001). Patients exposed to chemicals were younger than patients without such exposure; their median age at MDS diagnosis was 66 vs. 70 years (p = 0.037). Smokers had significantly lower hemoglobin concentrations (8.6 vs. 9.1 g/dl; p = 0.032) and lower platelet counts (99 × 109/l vs. 137 × 109/l; p < 0.001) than nonsmokers. We provide the first description of the characteristics of Polish MDS patients. Females predominated in the group aged <60 years and they had higher platelet counts. The course of the disease is affected by toxic exposure and smoking.