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1.
Nanomaterials (Basel) ; 14(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38921885

RESUMEN

This study focuses on the influence of electrospray deposition parameters on the morphology, topography, optical and sensing properties of ZnO films deposited on gold electrodes of quartz crystal resonators. The substrate temperature, precursor feed rate and emitter's voltage were varied. Zinc acetate dehydrate dissolved in a mixture of deionized water, ethanol and acetic acid was used as a precursor. The surface morphology and average roughness of the films were studied by scanning electron microscopy (SEM) and 3D optical profilometry, respectively, while the optical properties were investigated by diffuse reflectance and photoluminescence measurements. The sensing response toward ammonia was tested and verified by the quartz crystal microbalance (QCM) method. The studies demonstrated that electrospray deposition parameters strongly influence the surface morphology, roughness and gas sensing properties of the films. The deposition parameters were optimized in order for the highest sensitivity toward ammonia to be achieved. The successful implementation of the electrospray method as a simple, versatile and low-cost method for deposition of ammonia-sensitive and selective ZnO films used as a sensing medium in QCM sensors was demonstrated and discussed.

2.
J Phys Chem A ; 128(26): 5100-5114, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38915245

RESUMEN

Blue organic light-emitting diodes (OLED) suffer from relatively short lifetimes and a comparatively low lighting efficiency. One of the approaches to improving their characteristics is the development of luminophores with the potential for thermally activated delayed fluorescence (TADF). Herein, a set of donor-spacer-acceptor compounds with potential for TADF are designed, synthesized, and computationally and spectroscopically characterized. The excited state dynamics of the most prospective dye is monitored by time-resolved fluorescence and transient absorption spectroscopy. The experimental data are obtained and processed by a newly developed method and supplemented by quantum chemical calculations. The comprehensive approach allowed rationalization of the complex cascade-type photophysical behavior. The most promising emitter is included in an OLED displaying a blue color with a maximum EQE of 4.9% and negligible efficiency roll-off at higher luminance.

3.
Microorganisms ; 12(3)2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38543598

RESUMEN

The uterine microbiota has been the subject of increasing study, but its interaction with the local immune system remains unclear. Successful embryo implantation relies on endometrial receptivity, which is pivotal for immunological tolerance to fetal antigens and precise regulation of inflammatory mediators. Emerging data suggest a dynamic interplay between endometrial microflora and the immune system, making dysbiosis a potential determinant of pregnancy outcomes. Imbalances in the regulation of immune cells in the endometrium and decidua have been associated with infertility, miscarriage, and obstetric complications. A thorough comprehension of the immune system in the female reproductive tract shows potential for improving women's health and pregnancy outcomes. The objective of this study was to evaluate the patterns of endometrial microbiota in patients with recurrent implantation failure (RIF) and recurrent pregnancy loss (RPL) and to explore their implications for endometrial immune cells and chronic endometritis (CE). Immune cells in biopsies from 107 RIF and 93 RPL patients were examined using flow cytometry. The endometrial microbial composition was analyzed using real-time polymerase chain reaction (RT-PCR). The research uncovered disrupted endometrial microbiota in most women with RIF and RPL, which was often associated with significant effects on lymphocytes, T cells, and uNK cells.

4.
Materials (Basel) ; 16(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37959622

RESUMEN

BaMoO4 was obtained via facile mechanochemical synthesis at room temperature and a solid-state reaction. An evaluation of the phase composition and structural and optical properties of BaMoO4 was conducted. The influence of different milling speeds on the preparation of BaMoO4 was explored. A shorter reaction time for the phase formation of BaMoO4 was achieved using a milling speed of 850 rpm. A milling speed of 500 rpm led to partial amorphization of the initial reagents and to prolongation of the synthesis time of up to 3 h of milling time. Solid-state synthesis was performed via heat treatment at 900 °C for 15 h. X-ray diffraction analysis (XRD), infrared (IR) and UV diffuse reflectance (UV-Vis) and photoluminescence (PL) spectroscopy were carried out to characterize the samples. Independently of the method of preparation, the obtained samples had tetragonal symmetry. The average crystallite sizes of all samples, calculated using Scherrer's formula, were in the range of 240 to 1540 Å. IR spectroscopy showed that more distorted structural MoO4 units were formed when the compound was synthesized via a solid-state reaction. The optical band gap energy of the obtained materials was found to decrease from 4.50 to 4.30 eV with increasing crystallite sizes. Green- and blue-light emissions were observed for BaMoO4 phases under excitation wavelengths of 330 and 488 nm. It was established that the intensity of the PL peaks depends on two factors: the symmetry of MoO4 units and the crystallite sizes.

5.
Luminescence ; 37(9): 1492-1503, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35817756

RESUMEN

Powder samples of Li2 CaGeO4 , Ca2 GeO4 , and Ca5 Ge3 O11 doped by 0.5, 1, 2, 3, 4 and 5 at% Eu3+ relative to the Ca2+ , were prepared using a conventional solid-state synthesis technique. X-ray diffraction (XRD) analyses confirmed obtaining the pure phases at all dopant concentrations. In parallel, single crystals of the three compounds with the experimentally found optimal Eu3+ concentration were grown using a flux method. Structural investigation on the single crystals were done with a special attention to the form of the Ca-O polyhedron, the mean Ca-O distance, the Ca-Ca distance in the structure, the distortion degree of the polyhedron, as well as the Eu-Ca substitution site. The main spectral characteristics were analyzed and several relationships between the structural and spectra features were found. The optimal dopant concentration was 3 at% for Ca2 GeO4 and 4at% for Ca5 Ge3 O11 and Li2 CaGeO4 . Commission Internationale de l'éclairage coordinates of the samples showed emission colours in the red region close to the standard red coordinates and slightly influenced by the active ion concentration. The obtained results showed that europium-doped Li2 CaGeO4 , Ca2 GeO4 , and Ca5 Ge3 O11 could be used as red phosphors.


Asunto(s)
Europio , Luminiscencia , Cristalografía por Rayos X , Europio/química , Litio
6.
Clin Appl Thromb Hemost ; 23(6): 585-595, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26739544

RESUMEN

OBJECTIVE: To evaluate the contribution of rs5918ITGB3 on the incidence and recurrence of deep venous thrombosis (DVT) in women and the relationship with body mass index (BMI) and smoking and to compare with data in men. RESULTS: Rs5918(C) polymorphism in ITGB3 gene was assessed in 224 patients diagnosed with DVT and 216 controls. Thrombophilic genetic variant rs5918(C) was significantly pronounced in women (χ2 =7.565, P = .008) and total patients (χ2 = 9.266, P = .002) but not in men. Women patients (<45 years) who were carriers of rs5918ITGB3 polymorphism had an early onset of DVT (34.5 vs 39.4 years, χ2 = 7.027, P = .008) as analyzed by Kaplan-Meier and a higher risk of the recurrent event (χ2 = 3.405, odds ratio = 2.581, P = .044). The period before recurrent venous thromboembolism event was related to smoking status and BMI in young female who were carriers of rs5918 polymorphism but not in the males. CONCLUSIONS: Carriage of genetic variant rs5918(C) polymorphism in ITGB3 gene in women contributes to higher risk of single and recurrent DVT events at younger age.


Asunto(s)
Índice de Masa Corporal , Integrina beta3/genética , Polimorfismo Genético , Fumar , Trombosis de la Vena/etiología , Adulto , Factores de Edad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Recurrencia , Factores de Riesgo , Factores Sexuales
7.
Rom J Morphol Embryol ; 55(1): 57-62, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24715166

RESUMEN

Autophagy has emerged not only as an essential repair mechanism to degrade damaged organelles and proteins but also as a major player in protection of tumor cells from multiple stresses. It was shown that autophagy gene polymorphisms are correlated with development of chronic inflammatory lesions, which represent a risk factor for colorectal tumors. In this study, we aimed to determine if ATG16L1 +898A>G (Thr300Ala) polymorphism is associated with an increased risk of developing colorectal cancer (CRC) and to establish correlations between ATG16L1 genotypes and the major clinical and morphological parameters. We observed that subjects carrying GG genotype were at a higher risk for CRC (OR 1.99, 95% CI: 1.02-3.91, p=0.039) when compared with the more frequent AA genotype, furthermore this was even more consistent in male subjects (OR 2.72, 95% CI: 1.11-6.63, p=0.019) but not in female subjects (OR 1.29, 95% CI: 0.43-3.86, p=0.652). In addition, we noticed a correlation between ATG16L1 GG genotype and tumor stage in moderately and poorly differentiated CRC cases. GG genotype carrying patients were at a higher risk for CRC (OR 5.19, 95% CI: 1.50-17.87, p=0.002) when compared with the more frequent AA genotype. Such correlation suggests a possible role of autophagy gene polymorphisms in the development of human colorectal cancer.


Asunto(s)
Autofagia/genética , Proteínas Portadoras/genética , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Anciano , Proteínas Relacionadas con la Autofagia , Neoplasias Colorrectales/patología , Femenino , Frecuencia de los Genes/genética , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Factores de Riesgo , Rumanía
8.
Fertil Steril ; 100(5): 1321-5, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23899942

RESUMEN

OBJECTIVE: To study the influence of M2/ANXA5 for recurrent pregnancy loss (RPL), according to the timing of miscarriages and assess the male partner risk. DESIGN: Genetic association study. SETTING: Academic research center. PATIENT(S): Female patients from two academic centers in Germany and Bulgaria with two or more unexplained miscarriages were selected for this study. Male partners were available for a part of the German sample. Population controls were recruited from healthy individuals of respective populations. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Incidence of M2 carriage and odds ratios were calculated between patient and control groups, and RPL risk was evaluated. RESULT(S): The M2 haplotype in ANXA5 was associated with greater overall RPL risk in German and in Bulgarian women, and a trend of higher prevalence was seen for male partners of German RPL patients. The highest relative risk of M2 carriage was observed in women of both populations with "early" fetal losses between the 10th and 15th gestational weeks, which was significant in the meta-analysis. CONCLUSION(S): M2 carriage seems to have an RPL risk role mostly for early abortions, gestational weeks 10-15. In the first phase of pregnancy this correlates with vascular remodeling to accomplish the transition from high- to low-resistance blood vessels.


Asunto(s)
Aborto Espontáneo/genética , Anexina A5/genética , Padre , Haplotipos , Heterocigoto , Madres , Aborto Habitual/epidemiología , Aborto Habitual/genética , Aborto Espontáneo/epidemiología , Adulto , Bulgaria/epidemiología , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Alemania/epidemiología , Edad Gestacional , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Fenotipo , Embarazo , Prevalencia , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Adulto Joven
9.
Eur J Epidemiol ; 28(8): 621-47, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23900608

RESUMEN

Genetic and environmental factors interact in determining the risk of venous thromboembolism (VTE). The risk associated with the polymorphic variants G1691A of factor V (Factor V Leiden, FVL), G20210A of prothrombin (PT20210A) and C677T of methylentetrahydrofolate reductase (C677T MTHFR) genes has been investigated in many studies. We performed a pooled analysis of case-control and cohort studies investigating in adults the association between each variant and VTE, published on Pubmed, Embase or Google through January 2010. Authors of eligible papers, were invited to provide all available individual data for the pooling. The Odds Ratio (OR) for first VTE associated with each variant, individually and combined with the others, were calculated with a random effect model, in heterozygotes and homozygotes (dominant model for FVL and PT20210A; recessive for C677T MTHFR). We analysed 31 databases, including 11,239 cases and 21,521 controls. No significant association with VTE was found for homozygous C677T MTHFR (OR: 1.38; 95 % confidence intervals [CI]: 0.98-1.93), whereas the risk was increased in carriers of either heterozygous FVL or PT20210 (OR = 4.22; 95 % CI: 3.35-5.32; and OR = 2.79;95 % CI: 2.25-3.46, respectively), in double heterozygotes (OR = 3.42; 95 %CI 1.64-7.13), and in homozygous FVL or PT20210A (OR = 11.45; 95 %CI: 6.79-19.29; and OR: 6.74 (CI 95 % 2.19-20.72), respectively). The stratified analyses showed a stronger effect of FVL on individuals ≤ 45 years (p value for interaction = 0.036) and of PT20210A in women using oral contraceptives (p-value for interaction = 0.045). In this large pooled analysis, inclusive of large studies like MEGA, no effect was found for C677T MTHFR on VTE; FVL and PT20210A were confirmed to be moderate risk factors. Notably, double carriers of the two genetic variants produced an impact on VTE risk significantly increased but weaker than previously thought.


Asunto(s)
Factor V/genética , Predisposición Genética a la Enfermedad , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Protrombina/genética , Tromboembolia Venosa/genética , Estudios de Casos y Controles , Humanos , Factores de Riesgo
10.
Am J Reprod Immunol ; 68(3): 189-98, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22620672

RESUMEN

In connection with the embryo acceptance process after IVF procedure, endometrial cells surface receptors, extracellular matrix (ECM) molecules, endothelium and blood circulation factors were involved in remodelling of endometrium. Plasminogen activator inhibitor type 1 plays a significant role during the early phases of placental vascular remodelling and regulates the trophoblast invasion through controlling plasmin activity. Endometrial cell surface protein integrin alphaV/beta3, responsible for the adhesion of the embryo, has had also the same subunit beta3, which is component of integrin alphaIIb/beta3 connected with platelet aggregability. Prothrombin, furthermore, has had a debatable effect upon endothelial and mesenchymal cells and possible contribution on embryo vascular development. Confoundable data have been present about the role of coagulation factor V and its role for implantation. These and other coagulation factors have relatively common gene polymorphisms that enhanced their activity. This review discusses the effect of increased coagulation activity on implantation process, which is not yet fully determined. The establishment of the positive or negative impact of mother hypercoagulability on the success of embryo implantation after assisted reproduction technology could determine the timing of preventing anticoagulant therapy in women with history of early embryo loss.


Asunto(s)
Implantación del Embrión , Endometrio/metabolismo , Factor V/metabolismo , Infertilidad/sangre , Integrina alfaVbeta3/sangre , Trombofilia/sangre , Endometrio/patología , Matriz Extracelular/metabolismo , Femenino , Fertilización In Vitro , Humanos , Infertilidad/complicaciones , Inhibidor 1 de Activador Plasminogénico/sangre , Glicoproteína IIb de Membrana Plaquetaria/sangre , Protrombina/metabolismo , Trombofilia/complicaciones , Insuficiencia del Tratamiento , Trofoblastos/metabolismo
11.
Clin Appl Thromb Hemost ; 17(2): 181-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19959492

RESUMEN

The aim of our study was to investigate the significance of platelet-leukocyte aggregates (PLA) in women with recurrent pregnancy loss (RPL) as well as to identify association between common thrombophilic factors and whole blood levels of PLA in these patients. We measured PLA by whole blood flow cytometry in 66 nonpregnant women with hereditary and/or acquired thrombophilia and RPL, classified to 3 study groups, according to the type of losses (first, second, and third trimester) and 35 age-matched healthy controls. Platelet-leukocyte aggregates levels in all study groups were significantly increased compared to the control group (median values 2.13%, 2.32%, and 2.41%, vs median value in the control group 1.39%, P < .05 for all comparisons). Women with a single thrombophilic factor and women with combination of thrombophilic factors did not differ significantly as regards the PLA levels (2.13% vs 2.27%, P = .4). This study suggests that PLA may have a role in the pathogenesis of RPL in women affected by hereditary or acquired thrombophilia.


Asunto(s)
Aborto Habitual/sangre , Plaquetas , Leucocitos , Complicaciones Hematológicas del Embarazo/sangre , Trimestres del Embarazo/sangre , Trombofilia/sangre , Adulto , Femenino , Citometría de Flujo , Humanos , Embarazo , Estudios Prospectivos
12.
Fertil Steril ; 94(7): 2843-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21109038

RESUMEN

Polymorphism A1/A2 in the ß3 subunit of integrins αIIb/ß3 and αV/ß3 is implicated in the risk of development of embryonic and fetal recurrent pregnancy loss (RPL). In 191 women with RPL, polymorphism A1/A2 was statistically significantly associated with RPL at <10 weeks of gestation (29.3% versus 16.4% in controls), but it was much more pronounced in 67 women with RPL between 10 and 20 weeks of gestation (41.8%), illustrating its role in recurrent fetal loss.


Asunto(s)
Aborto Habitual/genética , Implantación del Embrión/genética , Integrina beta3/genética , Placentación/genética , Polimorfismo Genético , Aborto Habitual/patología , Adulto , Alelos , Antígenos de Superficie/genética , Antígenos de Superficie/metabolismo , Antígenos de Superficie/fisiología , Estudios de Casos y Controles , Pérdida del Embrión/genética , Pérdida del Embrión/patología , Femenino , Predisposición Genética a la Enfermedad , Edad Gestacional , Humanos , Infertilidad Femenina/genética , Infertilidad Femenina/patología , Integrina beta3/metabolismo , Integrina beta3/fisiología , Polimorfismo Genético/fisiología , Embarazo , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Subunidades de Proteína/fisiología
13.
Blood Coagul Fibrinolysis ; 20(2): 134-40, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19786941

RESUMEN

To investigate the impact of maternal-inherited thrombophilia: effects of factor V Leiden (FVL) and prothrombin gene mutation (FII 20210G>A) on the development of recurrent pregnancy loss in embryonic and postembryonic periods. A total of 153 patients were analysed for FVL and FII 20210G>A according to placenta gestation: 94 women with embryonic loss prior 10 weeks of gestation and 59 women with postembryonic (early fetal) loss occurring between 10 and 14 weeks of gestation. The control group consisted of 100 healthy women, with at least one uncomplicated full-term pregnancy. FVL prevalence was not significantly associated with pregnancy loss prior to 10 weeks of gestation (9.6%) compared with controls (7%) [odds ratio (OR) 1.41; 95% confidence interval (CI) 0.454-4.416, P > 0.05], but it was much more pronounced in women with postembryonic loss (10-14 weeks of gestation) - 18.6% (OR 3.05; 95% CI 1.010-9.387, P = 0.047). FII 20210G>A was significantly higher in both groups with embryonic (17%) and early fetal losses (16.9%) as compared to controls (3%) (OR 6.63; 95% CI 1.731-29.752, P = 0.003; OR 6.60; 95% CI 1.572-31.856, P = 0.006). FII 20210G>A is significantly associated with an increased risk of early recurrent pregnancy loss throughout the entire first trimester. FVL was significantly higher only in early fetal period after starting of the placentation process, but not associated with embryonic recurrent pregnancy loss. These results suggested that the first trimester should be viewed rather as a heterogeneous interval, with different relation to FVL in the embryonic and postembryonic fetal period. Genetic testing should be applied according to the diverse contribution of thrombophilic markers to embryonic and postembryonic period.


Asunto(s)
Pérdida del Embrión/genética , Factor V/genética , Enfermedades Genéticas Congénitas/genética , Edad Gestacional , Complicaciones Hematológicas del Embarazo/genética , Trombofilia/genética , Adolescente , Adulto , Anciano , Pérdida del Embrión/etiología , Femenino , Enfermedades Genéticas Congénitas/complicaciones , Humanos , Persona de Mediana Edad , Mutación Missense , Embarazo , Estudios Prospectivos , Protrombina/genética , Trombofilia/complicaciones
14.
Lung ; 186(1): 27-36, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18097719

RESUMEN

The importance of genetic thrombophilic factors in the development of venous thromboembolism has been increasingly recognized. Factor V Leiden (FVL), prothrombin gene mutation G20210A (FII G20210), genetic variant C677T of the methylentetrahydrofolate reductase (MTHFR), as well as the polymorphism A2 (PlA2) in platelet glycoprotein IIb/IIIa were recently discussed. We analyzed the contribution of genetic thrombophilic factors to the pathogenesis of pulmonary embolism (PE) and their association with the early onset and recurrence of PE using DNA analysis methods. In this case control trial we found thrombophilic genetic variants in 58.8% of 51 patients with PE. FVL was found in 23.5% of the patients versus 7.1% of the 98 controls (p=0.01), PlA2 IIb/IIIa was found in 35.3% vs. 14.3% (p=0.03), and FII G20210A was found in 5.9% vs. 2.0% (NS). Patients with recurrent PE had a very high prevalence of genetic factors, 70.4%. High prevalence of FVL was found in patients under 45 years of age: 39.3% (OR=14.23, 95% CI=1.58-330.03, p=0.01) as well as in patients with recurrent incidence (37%, OR=7.647, 95% CI=2.27-26.44, p=0.001). FVL was also significantly higher in the subgroup of patients with PE combined with deep venous thrombosis (OR=6.500, 95% CI=1.81-23.76, p=0.002) in comparison with patients with isolated PE (OR=2.261, 95% CI=0.50-9.69). The carriers of FVL are at higher risk for early and recurrent PE events. High prevalence of PlA2 in PE patients evidently shows the impact of this polymorphism in PE development. A different treatment should be considered in carriers of thrombophilic defects.


Asunto(s)
Factor V/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Mutación , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética , Polimorfismo Genético , Protrombina/genética , Embolia Pulmonar/genética , Trombofilia/complicaciones , Adulto , Factores de Edad , Edad de Inicio , Anciano , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Embolia Pulmonar/epidemiología , Recurrencia , Medición de Riesgo , Factores de Riesgo , Trombofilia/genética , Trombosis de la Vena/complicaciones , Trombosis de la Vena/genética
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