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1.
Materials (Basel) ; 17(6)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38541553

RESUMEN

In this work, two methods were used to accelerate the corrosion of concrete. In the first method, chloride ions were injected into the concrete using the migration method. The moment of the initiation of the corrosion process was monitored using an electrochemical method of measuring polarization resistance. In the next step, the corrosion process was accelerated by the electrolysis process. Changes on the sample surface were also monitored using a camera. In the second method, the corrosion process of the reinforcing bar was initiated by the use of the electrolysis process only. Here, changes occurring on the surfaces of the tested sample were recorded using two web cameras placed on planes perpendicular to each other. Continuous measurement of the current flowing through the system was carried out in both cases. It was assumed that in conditions of natural corrosion, a crack would occur when the sum of the mass loss of the reinforcing bar due to corrosion reached the same value in tcr(real) (real time) as it reached in the tcr (time of cracking) during the accelerated corrosion test. The real time value was estimated for C1 concrete with cement CEM I. The estimated value was tcr(real) = 1.1 years and for C2 concrete with cement CEM III, tcr(real) = 11.2 years. However, the main difference that was observed during the tests was the nature of the concrete cracks. In the case of the C1 concrete sample, these occurred along the reinforcing bar, while in the C2 concrete, the failures occurred on a perpendicular plane transverse to the direction of the reinforcing bar.

2.
Environ Sci Technol ; 58(3): 1636-1647, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38186056

RESUMEN

Mine dust has been linked to the development of pneumoconiotic diseases such as silicosis and coal workers' pneumoconiosis. Currently, it is understood that the physicochemical and mineralogical characteristics drive the toxic nature of dust particles; however, it remains unclear which parameter(s) account for the differential toxicity of coal dust. This study aims to address this issue by demonstrating the use of the partial least squares regression (PLSR) machine learning approach to compare the influence of D50 sub 10 µm coal particle characteristics against markers of cellular damage. The resulting analysis of 72 particle characteristics against cytotoxicity and lipid peroxidation reflects the power of PLSR as a tool to elucidate complex particle-cell relationships. By comparing the relative influence of each characteristic within the model, the results reflect that physical characteristics such as shape and particle roughness may have a greater impact on cytotoxicity and lipid peroxidation than composition-based parameters. These results present the first multivariate assessment of a broad-spectrum data set of coal dust characteristics using latent structures to assess the relative influence of particle characteristics on cellular damage.


Asunto(s)
Minas de Carbón , Exposición Profesional , Neumoconiosis , Humanos , Carbón Mineral/análisis , Polvo/análisis , Minerales
3.
Materials (Basel) ; 16(14)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37512432

RESUMEN

This paper presents the analysis of how ISP slag addition affects the effectiveness of chloride extraction from self-compacting concrete. Corrosion processes were initiated by chloride ions added to concrete by the method accelerated with an electric field. Corrosion of reinforcement was monitored using the method of linear polarization resistance (LPR). Polarization measurements of steel reinforcement and chloride profiles were analysed to evaluate the effectiveness of electrochemical extraction. Microstructural analysis was conducted on a specimen of concrete after migration and extraction of chlorides. The presence of chloride ions and the application of an electric field during migration were tested with respect to the changed microstructure of concrete evaluated on the basis of image analysis using a scanning electron microscope (SEM). The research contributes to a better understanding of the corrosion processes caused by the presence of chloride ions in concretes in which ISP slag was used as a substitute for sand in various amounts. Thanks to the treatments of concrete with already corroding reinforcement bars, it can be concluded that the moderate replacement of sand with ISP slag limited to 25% allows for the effective inhibition of corrosion processes taking place in these concretes. However, it is not possible to completely withdraw already started corrosion processes in steel. The observations of the microstructure of concrete in which sand was completely replaced with ISP slag indicate that after prolonged use of the chloride extraction process, we can expect a change in the microstructure and the formation of ettringite, which may cause the concrete structure to burst. The obtained information will contribute to the development of modelling methods for chloride ion extraction from a wide range of currently used concretes.

4.
Environ Geochem Health ; 45(10): 7363-7388, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37131112

RESUMEN

Exposure to dust from the mining environment has historically resulted in epidemic levels of mortality and morbidity from pneumoconiotic diseases such as silicosis, coal workers' pneumoconiosis (CWP), and asbestosis. Studies have shown that CWP remains a critical issue at collieries across the globe, with some countries facing resurgent patterns of the disease and additional pathologies from long-term exposure. Compliance measures to reduce dust exposure rely primarily on the assumption that all "fine" particles are equally toxic irrespective of source or chemical composition. For several ore types, but more specifically coal, such an assumption is not practical due to the complex and highly variable nature of the material. Additionally, several studies have identified possible mechanisms of pathogenesis from the minerals and deleterious metals in coal. The purpose of this review was to provide a reassessment of the perspectives and strategies used to evaluate the pneumoconiotic potency of coal mine dust. Emphasis is on the physicochemical characteristics of coal mine dust such as mineralogy/mineral chemistry, particle shape, size, specific surface area, and free surface area-all of which have been highlighted as contributing factors to the expression of pro-inflammatory responses in the lung. The review also highlights the potential opportunity for more holistic risk characterisation strategies for coal mine dust, which consider the mineralogical and physicochemical aspects of the dust as variables relevant to the current proposed mechanisms for CWP pathogenesis.


Asunto(s)
Minas de Carbón , Exposición Profesional , Neumoconiosis , Humanos , Polvo/análisis , Neumoconiosis/epidemiología , Neumoconiosis/etiología , Minas de Carbón/métodos , Carbón Mineral/toxicidad , Carbón Mineral/análisis , Minerales , Exposición Profesional/efectos adversos
5.
Materials (Basel) ; 16(2)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36676371

RESUMEN

This research paper is the result of observations made during tests according to various standards carried out on behalf of industry. The article presents diffusion coefficient values calculated according to the thermodynamic migration model for twenty different concrete mixes and some selected mixes of the codified approaches known as ASTM 1202, NT BUILD 443, NT BUILD 492, ASTM 1556. The method used here, according to the thermodynamic model of migration, allows determination of the value of the diffusion coefficient after short studies of the migration of chloride ions into concrete and was described in earlier works by one of the authors. Unfortunately, when using standard methods, the values of diffusion coefficients differ significantly from each other. In each concrete, diffusion tests were carried out in the conditions of long-term natural diffusion to verify the values determined by standard methods and according to the thermodynamic model of migration. The analysis conducted for this research paper reveals that the chloride permeability test method according to the standard ASTM C1202-97 has an almost 2.8-fold greater dispersion of the obtained results compared to the thermodynamic model of migration. It was observed that the standard NT BUILD 492 has a 3.8-fold dispersion of results compared to the method with the thermodynamic model of migration. The most time-consuming method is the standard method NT BUILD 443. The largest 3.5-fold dispersion of values concerning the reference value are observed in that method. Moreover, a method based on a thermodynamic migration model seems to be the best option of all analyzed methods. It is a quite quick, but laborious, method that should be tested for a larger number of concrete mixes. A great advantage of this method is that it is promising for a wide range of concrete mixtures, both plain concrete and concrete with various additives and admixtures, as well as high-performance concrete.

6.
Artículo en Inglés | MEDLINE | ID: mdl-35206179

RESUMEN

Molecular hydrogen (H2) is potentially a novel therapeutic gas for acute post-coronavirus disease 2019 (COVID-19) patients because it has antioxidative, anti-inflammatory, anti-apoptosis, and antifatigue properties. The aim of this study was to determine the effect of 14 days of H2 inhalation on the respiratory and physical fitness status of acute post-COVID-19 patients. This randomized, single-blind, placebo-controlled study included 26 males (44 ± 17 years) and 24 females (38 ± 12 years), who performed a 6-min walking test (6 MWT) and pulmonary function test, specifically forced vital capacity (FVC) and expiratory volume in the first second (FEV1). Symptomatic participants were recruited between 21 and 33 days after a positive polymerase chain reaction test. The experiment consisted of H2/placebo inhalation, 2 × 60 min/day for 14 days. Results showed that H2 therapy, compared with placebo, significantly increased 6 MWT distance by 64 ± 39 m, FVC by 0.19 ± 0.24 L, and, in FEV1, by 0.11 ± 0.28 L (all p ≤ 0.025). In conclusion, H2 inhalation had beneficial health effects in terms of improved physical and respiratory function in acute post-COVID-19 patients. Therefore, H2 inhalation may represent a safe, effective approach for accelerating early function restoration in post-COVID-19 patients.


Asunto(s)
COVID-19 , Femenino , Volumen Espiratorio Forzado , Humanos , Hidrógeno/uso terapéutico , Masculino , Pruebas de Función Respiratoria , SARS-CoV-2 , Método Simple Ciego
7.
J Interv Card Electrophysiol ; 64(3): 661-667, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34988847

RESUMEN

PURPOSE: Durable pulmonary vein (PV) isolation (PVI) determines the clinical success of catheter ablation for atrial fibrillation. In this randomized study, we investigated whether the temporally discontiguous deployment of ablation lesions adversely affected the acute efficacy of PVI. METHODS: Thirty-six consecutive patients with drug-refractory paroxysmal atrial fibrillation (aged 59 ± 11, 58% males) were randomized 1:1 to either discontiguous (D-PVI) or contiguous (C-PVI) encircling radiofrequency (RF) lesions around ipsilateral PVs. A contact force-sensing catheter was used targeting a final interlesion distance < 6 mm and the ablation index of 400-450 (anterior wall) and 300-350 (posterior wall). The study endpoint was defined as failure of first-pass PVI or acute PV reconnection during a waiting time (> 30 min) followed by adenosine challenge. RESULTS: The total RF time, number of RF lesions, and mean interlesion distance were comparable in both groups. Total endpoint rates were 1/36 (3%) in the D-PVI vs 4/36 (11%) in the C-PVI groups; P = 0.34 for superiority, P = 0.008 for non-inferiority. Adenosine-induced reconnection of right PVs was the only endpoint in the D-PVI group. In the C-PVI group, first-pass PVI failed in 2 right PVs and spontaneous reconnection occurred in 2 other circles (left and right PVs). CONCLUSION: Temporally discontiguous deployment of RF lesions is not associated with lower procedural PVI efficacy when strict criteria for interlesion distance and ablation index are applied. The development of local edema around each ablation site does not prevent effective RF lesion formation at adjacent positions. TRIAL REGISTRATION: clinicaltrials.gov (NCT03332862).


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Venas Pulmonares , Adenosina , Fibrilación Atrial/cirugía , Femenino , Humanos , Masculino , Venas Pulmonares/cirugía , Recurrencia , Resultado del Tratamiento
8.
Materials (Basel) ; 14(16)2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34443178

RESUMEN

The concrete cover is the basic protection of the reinforcement against the influence of external factors that may lead to its corrosion. Its effectiveness depends mainly on the composition of the concrete mix, including the cement used. Depending on external environmental factors that may aggressively affect the structure, various types of cements and concrete admixtures are recommended. The paper presents the results of tests that allow us to assess the effect of the type of cement used and the air-entraining agent on the effectiveness of the concrete cover as a layer protecting the reinforcement against corrosion. In order to initiate the corrosion process, the reinforced concrete specimens were subjected to cycles of freezing and thawing in a sodium chloride solution. The degree of advancement of the corrosion process was investigated using the electrochemical galvanostatic pulse technique. Additionally, the microstructure of specimens taken from the cover was observed under a scanning electron microscope. The research has shown that in the situation of simultaneous action of chloride ions and freezing cycles, in order to effectively protect the reinforcement against corrosion, the application of both blast-furnace slag cement and an air-entraining agent performed the best.

9.
Materials (Basel) ; 14(13)2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34279244

RESUMEN

The numerical modelling of chloride penetration into concrete is very sensitive to the correct description of the input data. In the recent era, high-performance concrete (HPC), which combines Portland cement and other supplementary cementitious materials, has been gaining attraction due to their desirable material properties and durability. The presented results show the application of the modified approach for the evaluation of the suitability of the time-dependent model for the variation of the diffusion coefficient. The 26 various binary and ternary-based concrete mixtures blended with volcanic pumice pozzolan (VPP) as a major supplementary cementitious material (SCM) are compared with the reference Ordinary Portland Cement mixture. Other SCMs namely fly ash, slag, silica fume, and metakaolin were also utilized in ternary-based concrete mixtures. In-depth statistical analysis was carried out to show the variability and effects of the amount of the volcanic pumice as an SCM on the diffusion coefficient. The mean value and regression via linear approximation of the time-dependent coefficient of variation of the diffusion coefficients were used as well as the Root of Mean Squared Error approach. The presented results are suitable as the component of the input parameters for the durability-related probabilistic assessment of the reinforced concrete structures exposed to chlorides. In addition, the time-dependent ultimate limit state-related data was presented.

10.
Materials (Basel) ; 12(24)2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31817567

RESUMEN

The presented article demonstrates the probabilistic method based modeling of the 2D chloride ingress into reinforced concrete structures with respect to concrete heterogeneity and epoxy-coated steel reinforcement. Spatial change of concrete diffusion is assessed through the investigation of random variation of the ability of concrete to resist chloride ingress. Time-dependent chloride concentration at the reinforcement level in both homogeneous and heterogeneous models is comparatively considered taking into account of the influence of reinforcement protection as well as the defects and holidays of the coating. Expansion optimal linear estimation method is exploited to generate a random field for the structure at the mesoscale and correlation length is employed to simplify the modeling process. Preliminary analyses of the built model are conducted in both deterministic and probabilistic solutions under the scheme of the finite element method. Thus, possibility of such analyses is exploited.

11.
Materials (Basel) ; 12(24)2019 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-31835727

RESUMEN

The presented research program is focused on the design of a structural lightweight fiber-reinforced concrete harnessing an internal curing process. Pre-soaked waste red ceramic fine aggregate and pre-soaked artificial clay expanded coarse aggregate were utilized for the creation of the mix. Copper-coated steel fiber was added to the mix by volume in amounts of 0.0%, 0.5%, 1.0%, and 1.5%. Test specimens in forms of cubes, cylinders, and beams were tested to specify the concrete characteristics. Such properties as consistency, compressive strength, splitting tensile strength, static and dynamic modulus of elasticity, flexural characteristics, and shear strength were of special interest. The achieved concrete can be classified as LC12/13. A strength class, according to fib Model Code, was also assigned to the concretes in question. The proposed method of preparation of concrete mix using only pre-soaked aggregate (with no extra water) proved to be feasible.

12.
PLoS One ; 14(10): e0224145, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31639174

RESUMEN

Ballet training has been reported to positively influence balance ability. It is not entirely clear how improved balance ability manifests under standing conditions with different demands on postural control. The aim of the study was to compare balance of ballet dancers and non-dancers in a unipedal stance under different conditions. Twenty-five professional ballet dancers and twenty-five controls completed four unipedal standing balance tests: firm surface with eyes open and closed; foam mat surface with eyes open; and firm surface with eyes open immediately after performing ten 360° whole-body turns. The centre of pressure (COP) data were obtained with a force platform and the direction-specific standard deviations, velocities, and sample entropy of the COP displacement were computed. A three-way analysis of variance was used to compare groups, genders, and conditions. For standing immediately after performing ten turns, the postural sway parameters were significantly larger in the control group compared to the ballet dancers in both men and women. In this stance condition the values of postural sway and COP velocities in the control group were larger in the men compared to the women. For both genders in the control group all postural sway and COP velocity parameters were larger in standing with eyes closed and standing after performing 10 turns compared to standing with eyes open on both firm and foam surface. In the ballet dancers all COP velocity parameters were larger in standing with eyes closed compared to all other conditions. The results from the present study indicate that professional ballet dancers do not have a better general balance ability than untrained subjects.


Asunto(s)
Baile/fisiología , Lateralidad Funcional/fisiología , Equilibrio Postural/fisiología , Postura/fisiología , Adulto , Femenino , Humanos , Masculino , Adulto Joven
13.
Materials (Basel) ; 12(7)2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30986966

RESUMEN

The safety and durability of bridges designed from weathering steels are conditioned by the development of a sufficiently protective layer of corrosion products. Air pollution, microclimate around the bridge, time of wetness, structural solution of the bridge, and the position and orientation of the surface within the bridge structure all influence the development of protective layers on the surface of the weathering steel. In this article, attention is focused mainly on the microclimatic effects resulting from the road traffic under the bridge. The influence of chloride deposition on the development of corrosion products is evaluated using experimental in situ testing. Two neighboring bridges made of weathering steel and crossing different types of obstacles were selected for this experiment. Relations and dependences between the measured parameters (deposition rate of chlorides, corrosion rates, thickness of corrosion products and the amount of chlorides in corrosion products) are evaluated and discussed.

14.
Artif Organs ; 43(8): 796-805, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30741435

RESUMEN

There is ample evidence that maintenance of basic physical fitness through exercise training is crucial for patients with chronic renal insufficiency. Rehabilitation based on neuromuscular electrical stimulation (NMES) of thigh muscles has been shown to have many beneficial effects in patients with chronic diseases. It is likely that NMES could have beneficial effects also in patients on chronic ambulatory peritoneal dialysis (CAPD). NMES was applied for 20 weeks to 14 patients on CAPD, mean age 61.9 (8.7) years, using battery-powered stimulators (CEFAR-REHAB X2; Sweden) and self-adhesive electrodes 80 × 130 mm (PALS Platinum; Denmark). Stimulation characteristics: biphasic current, pulse width 400 µs, 8 seconds contraction-12 seconds relaxation, frequency modulation 40-60 Hz, and maximal intensity 60 mA. NMES was home-based and applied simultaneously to quadriceps muscles of both legs (2 × 30 min/day). Functional performance, muscle power (Fmax ), arterial stiffness (assessed by cardio-ankle vascular index-CAVI), and quality of life by KDQOL-SF evaluation was done at baseline and at the end of program. Home NMES improved significantly the main functional parameters: VO2peak /kg increased by +2.2 (1.6) mL O2 /kg/min (P < 0.002), peak workload by +0.1 (0.1) W/kg (P < 0.005), and distance walked in 6 MWT by +44.7 (58.4) m (P < 0.008). Only insignificant changes were observed in CAVI and Fmax . KDQOL-SF analysis showed significant improvement in seven parameters of QoL (P < 0.012-0.049). This pilot study is the first clinical report dealing with the use of NMES in patients on CAPD. The results demonstrate that an improvement of exercise capacity and QoL can be achieved by home-based NMES in CAPD patients.


Asunto(s)
Terapia por Estimulación Eléctrica , Diálisis Peritoneal Ambulatoria Continua , Músculo Cuádriceps , Insuficiencia Renal Crónica/terapia , Anciano , Terapia por Estimulación Eléctrica/métodos , Tolerancia al Ejercicio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular , Proyectos Piloto , Músculo Cuádriceps/fisiopatología , Calidad de Vida , Insuficiencia Renal Crónica/fisiopatología , Rigidez Vascular , Prueba de Paso
15.
Front Immunol ; 9: 3069, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30687311

RESUMEN

Exposure to silica and the consequent development of silicosis are well-known health problems in countries with mining and other dust producing industries. Apart from its direct fibrotic effect on lung tissue, chronic and immunomodulatory character of silica causes susceptibility to tuberculosis (TB) leading to a significantly higher TB incidence in silica-exposed populations. The presence of silica particles in the lung and silicosis may facilitate initiation of tuberculous infection and progression to active TB, and exacerbate the course and outcome of TB, including prognosis and survival. However, the exact mechanisms of the involvement of silica in the pathological processes during mycobacterial infection are not yet fully understood. In this review, we focus on the host's immunological response to both silica and Mycobacterium tuberculosis, on agents of innate and adaptive immunity, and particularly on silica-induced immunological modifications in co-exposure that influence disease pathogenesis. We review what is known about the impact of silica and Mycobacterium tuberculosis or their co-exposure on the host's immune system, especially an impact that goes beyond an exclusive focus on macrophages as the first line of the defense. In both silicosis and TB, acquired immunity plays a major role in the restriction and/or elimination of pathogenic agents. Further research is needed to determine the effects of silica in adaptive immunity and in the pathogenesis of TB.


Asunto(s)
Susceptibilidad a Enfermedades/inmunología , Mycobacterium tuberculosis/inmunología , Exposición Profesional/efectos adversos , Dióxido de Silicio/efectos adversos , Tuberculosis/etiología , Animales , Presentación de Antígeno/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Humanos , Inmunidad , Macrófagos/inmunología , Macrófagos/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Tuberculosis/microbiología
16.
Europace ; 20(7): 1107-1114, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28575490

RESUMEN

Aims: Complications of catheter ablation for atrial fibrillation (AF) are frequently related to vascular access. We hypothesized that ultrasound-guided (USG) venipuncture may facilitate the procedure and reduce complication rates. Methods and results: We conducted a multicentre, randomized trial in patients undergoing catheter ablation for AF on uninterrupted anticoagulation therapy. The study enrolled consecutive 320 patients (age: 63 ± 8 years; male: 62%) and were randomized to USG or conventional venipuncture in 1:1 fashion. It was prematurely terminated due to substantially lower-than-expected complication rates, which doubled the population size needed to maintain statistical power. While the complication rates did not differ between two study arms (0.6% vs. 1.9%, P = 0.62), intra-procedural outcome measures were in favour of the USG approach (puncture time, 288 vs. 369 s, P < 0.001; first pass success, 74% vs. 20%, P < 0.001; extra puncture attempts 0.5 vs. 2.1, P < 0.001; inadvertent arterial puncture 0.07 vs. 0.25, P < 0.001; unsuccessful cannulation 0.6% vs. 14%, P < 0.001). Though these measures varied between trainees (49% of procedures) and expert operators, between-arm differences (except for unsuccessful cannulation) were comparably significant in favour of USG approach for both subgroups. Conclusions: Ultrasound-guided puncture of femoral veins was associated with preferable intra-procedural outcomes, though the major complication rates were not reduced. Both trainees and expert operators benefited from the USG strategy. (www.clinicaltrials.gov ID: NCT02834221).


Asunto(s)
Fibrilación Atrial/cirugía , Ablación por Catéter , Cateterismo Periférico/métodos , Vena Femoral/diagnóstico por imagen , Ultrasonografía Intervencional , Anciano , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Ablación por Catéter/efectos adversos , Cateterismo Periférico/efectos adversos , República Checa , Terminación Anticipada de los Ensayos Clínicos , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Punciones , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
17.
Artículo en Inglés | MEDLINE | ID: mdl-29097820

RESUMEN

AIMS: The purpose of this study was to evaluate swallowing changes in post-stroke patients with dysphagia after four weeks of suprahyoid muscles electrical stimulation. METHODS: This was a prospective randomized study of early stage stroke patients with dysphagia. Electrical stimulation of suprahyoid muscles was given to a group of 54 patients (26 men, average age 70 years) for 20 minutes a day, 5 days a week. Standard orofacial rehabilitation without electrical stimulation was carried out on a control group of 54 patients (31 men, average age 69 years). Swallowing was evaluated at the beginning of the study and at the end, by videofluoroscopy - measuring the time for oral and pharyngeal phases. RESULTS: The difference in duration of oral transit time (OTT) after the therapy between the study group (average: 0.55 ± 0.01) and the control group (average: 0.29 ± 0.03) was statistically significant (P=0.01). Difference in duration of the pharyngeal transit time (PTT) after the therapy between the study group (average: 0.37 ± 0.02) and control group (average: 0.15 ± 0.02) was also statistically significant (P=0.009). CONCLUSION: Electrical stimulation of suprahyoid muscles significantly reduced the duration of the oral and pharyngeal phases: in the post-stroke patients with dysphagia used in this study. The result is improved swallowing. This is a recently recommended approach and your study confirms its efficacy.


Asunto(s)
Trastornos de Deglución/rehabilitación , Deglución/fisiología , Terapia por Estimulación Eléctrica , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/complicaciones , Anciano , Trastornos de Deglución/etiología , Trastornos de Deglución/fisiopatología , Trastornos de Deglución/terapia , Femenino , Humanos , Masculino , Estudios Prospectivos , Recuperación de la Función , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
18.
PLoS One ; 12(4): e0175880, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28426799

RESUMEN

The approach for the detection of replicational activity in cells using 5-bromo-2'-deoxyuridine, a low concentration of hydrochloric acid and exonuclease III is presented in the study. The described method was optimised with the aim to provide a fast and robust tool for the detection of DNA synthesis with minimal impact on the cellular structures using image and flow cytometry. The approach is based on the introduction of breaks into the DNA by the low concentration of hydrochloric acid followed by the subsequent enzymatic extension of these breaks using exonuclease III. Our data showed that the method has only a minimal effect on the tested protein localisations and is applicable both for formaldehyde- and ethanol-fixed cells. The approach partially also preserves the fluorescence of the fluorescent proteins in the HeLa cells expressing Fluorescent Ubiquitin Cell Cycle Indicator. In the case of the short labelling pulses that disabled the use of 5-ethynyl-2'-deoxyuridine because of the low specific signal, the described method provided a bright signal enabling reliable recognition of replicating cells. The optimized protocol was also successfully tested for the detection of trifluridine, the nucleoside used as an antiviral drug and in combination with tipiracil also for the treatment of some types of cancer.


Asunto(s)
Bromodesoxiuridina/metabolismo , Ciclo Celular , Exodesoxirribonucleasas/metabolismo , Ácido Clorhídrico/farmacología , Células A549 , Citometría de Flujo , Células HeLa , Humanos , Microscopía Fluorescente
19.
PLoS One ; 12(3): e0174893, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28358913

RESUMEN

5-Bromo-2'-deoxyuridine (BrdU) labelling and immunostaining is commonly used for the detection of DNA replication using specific antibodies. Previously, we found that these antibodies significantly differ in their affinity to BrdU. Our present data showed that one of the reasons for the differences in the replication signal is the speed of antibody dissociation. Whereas highly efficient antibodies created stable complexes with BrdU, the low efficiency antibodies were unstable. A substantial loss of the signal occurred within several minutes. The increase of the complex stability can be achieved by i) formaldehyde fixation or ii) a quick reaction with a secondary antibody. These steps allowed the same or even higher signal/background ratio to be reached as in the highly efficient antibodies. Based on our findings, we optimised an approach for the fully enzymatic detection of BrdU enabling the fast detection of replicational activity without a significant effect on the tested proteins or the fluorescence of the fluorescent proteins. The method was successfully applied for image and flow cytometry. The speed of the method is comparable to the approach based on 5-ethynyl-2'-deoxyuridine. Moreover, in the case of short labelling pulses, the optimised method is even more sensitive. The approach is also applicable for the detection of 5-trifluoromethyl-2'-deoxyuridine.


Asunto(s)
Anticuerpos/química , Bromodesoxiuridina/química , Replicación del ADN/fisiología , Células A549 , Ciclo Celular , Cobre/química , Citometría de Flujo , Células HeLa , Humanos , Microscopía Fluorescente
20.
Steroids ; 117: 97-104, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27543674

RESUMEN

Sesquiterpene lactone trilobolide is a sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor, thus depleting the Ins(1,4,5)P3-sensitive intracellular calcium stores. Here, we describe a synthesis of a series of 6 trilobolide-steroids conjugates (estradiol, pregnene, dehydroepiandrosterone, and testosterone). We found that the newly synthesized Tb-based compounds possess different remarkable biological activities. Cancer cell cytotoxicity and preferential selectivity is represented in our study by a Tb-pregnene derivative. The most cytotoxic clickates of estradiol and pregnene were studied by FACS where impact on cell cycle and RNA synthesis was observed; live-cell microscopy revealed the impact on cell organelle morphology particularly endoplasmic reticulum, mitochondria and nucleus. Further, we have studied the estrogenic and androgenic properties of the clickate molecules using cell-based luciferase assays. Finally, antimycobacterial tests revealed that testosterone and estradiol derivatives potentiated the antimycobacterial activity up to IC50 of 10.6µM.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Butiratos/química , Furanos/química , Esteroides/química , Células A549 , Animales , Antibacterianos/síntesis química , Candida/efectos de los fármacos , Línea Celular Tumoral , Química Clic , Células HCT116 , Humanos , Estructura Molecular , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Esteroides/metabolismo
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