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1.
Mater Sci Eng C Mater Biol Appl ; 123: 112002, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33812622

RESUMEN

The paper focuses on the SiOx-doped amorphous hydrocarbon (a-C:H:SiOx) coating on the titanium (Ti-6Al-4V) alloy substrate obtained by plasma-assisted chemical vapor deposition (PACVD) in a mixture of argon gas and polyphenylmethylsiloxane vapor using a bipolar substrate bias. It is shown that the a-C:H:SiOx coating deposition results in the formation of a negative surface potential important for application of this coating for medical implants. The a-C:H:SiOx coatings improve the corrosion resistance of Ti alloy to 0.5 M NaCl solution and phosphate-buffered saline. In particular, the corrosion current density of the a-C:H:SiOx-coated sample in a 0.5 M NaCl solution at 22 °C decreases from 1∙10-8 to 1.7∙10-10 A/cm2, that reduces the corrosion rate from 9∙10-5 to 15∙10-7 mm/year. The a-C:H:SiOx coating facilitates the surface endothelization of an implant located in the thoracic aorta of a mini pig, and reduces the risk of thrombosis and implant failure. This effect can be explained by the ability of the a-C:H:SiOx coating ability to reduce in vitro a 24-hour secretion of pro-inflammatory interleukins (IL-6, IL-12(p70), IL-15, and IL-17) and cytokines (IFN-g and TNF-a) by blood mononuclear cells (MNCs) and elevates the concentration of anti-inflammatory interleukin IL-1Ra. In vitro analysis shows no cytotoxicity of the a-C:H:SiOx coating for the human blood MNCs, suggesting a promising PACVD on Ti alloys for cardiovascular implants, including pumps for mechanical heart support systems.


Asunto(s)
Titanio , Aleaciones , Animales , Corrosión , Ensayo de Materiales , Propiedades de Superficie , Porcinos , Porcinos Enanos , Titanio/farmacología
2.
Cytometry A ; 91(9): 867-873, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28544427

RESUMEN

Whereas modern automated blood cell analyzers measure the volume of individual red blood cells (RBCs), leading to four RBC indices (mean corpuscular volume, MCV; mean corpuscular hemoglobin, MCH; mean corpuscular hemoglobin concentration, MCHC; red cell distribution width, and RDW), the RBC shape has not been assessed by clinical screening tools. We applied the scanning flow cytometer (SFC) for complete characterization of intact RBC morphology in terms of diameter, maximal and minimal thicknesses, volume, surface area, sphericity index, spontaneous curvature, hemoglobin concentration, and content. The above-mentioned individual RBC characteristics were measured without fluorescent markers and other chemicals by a SFC equipped only with 660 nm laser for RBC illumination and single detector for measurement of angle-resolved light scattering. The distributions over all RBC characteristics were constructed and processed statistically to form the novel 31 RBC indices for 22 donor samples. Our results confirm the possibility of precise, label-free, enhanced morphological analysis of individual intact RBCs with compact single-detector flow cytometer. Detailed characterization of RBCs with high statistics and precision can be used to increase the value of screening examinations and to reveal pathologies accompanied by abnormality of RBC shape. © 2017 International Society for Advancement of Cytometry.


Asunto(s)
Eritrocitos/citología , Recuento de Eritrocitos/métodos , Índices de Eritrocitos/fisiología , Eritrocitos/metabolismo , Citometría de Flujo/métodos , Hemoglobinas/metabolismo , Humanos , Rayos Láser
3.
Cytometry A ; 89(11): 1010-1016, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27768824

RESUMEN

Whereas commercially available hematological analyzers measure volume of individual platelets, angle-resolved light-scattering provides unique ability to additionally measure their shape index. We utilized the scanning flow cytometer to measure light-scattering profiles (LSPs) of individual platelets taken from 16 healthy donors and the solution of the inverse light-scattering problem to retrieve the volume and shape index of each platelet. In normal conditions, the platelet shape index distribution (PSID) demonstrates three peaks, which relate to resting, partially activated, and fully activated platelets. We developed an algorithm, based on fitting PSID by a sum of three peak functions, to determine the percentage, mean platelet shape index, and distribution width of each platelet fraction. In total, this method gives eight additional parameters of platelet morphology and function to be used in clinical hematological analysis. We also stimulated the platelets with adenosine diphosphate (ADP) and measured the dependence of equilibrium PSID, including the total percentage of activated platelets, on ADP concentration. © 2016 International Society for Advancement of Cytometry.


Asunto(s)
Algoritmos , Plaquetas/citología , Citometría de Flujo/métodos , Humanos
4.
Klin Lab Diagn ; 61(2): 87-90, 2016 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-27455561

RESUMEN

The study was carried out to diferentiate reference values for kaolin-activated thromboelastography in newborns with congenital heart disease. The study included two groups ofpatients. The first one consisted of 62 newborns with congenital heart disease and the second one consisted of 35 healthy newborns. The results of kaolin-activated thromboelastography implemented in groups are evaluated as condition of normal coagulation. The valuable diferences of homeostasis system in healthy newborns and newborns with congenital heart disease (without severe concomitant pathology) are not established. They have similar indicators of kaolin-activated thromboelastography. The derived results can be applied as standards in full-term newborns with congenital heart disease.


Asunto(s)
Coagulación Sanguínea , Cardiopatías Congénitas/sangre , Tromboelastografía/métodos , Estudios de Casos y Controles , Femenino , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/patología , Humanos , Recién Nacido , Caolín/química , Masculino , Tiempo de Tromboplastina Parcial/estadística & datos numéricos , Tiempo de Protrombina/estadística & datos numéricos , Valores de Referencia , Tiempo de Trombina/estadística & datos numéricos , Tiempo de Coagulación de la Sangre Total/estadística & datos numéricos
5.
Thromb Res ; 135(5): 788-95, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25754229

RESUMEN

INTRODUCTION: Our objective was to investigate the association between gene polymorphisms of folate cycle (MTHFR 677 C>T, MTHFR 1298 A>C, MTR 2756 A>G, and MTRR 66 A>G) and the risk of pulmonary embolism (PE) in a case-control study. MATERIALS AND METHODS: 177 PE patients (87 women and 90 men) were compared to a healthy control group (461 people, 123 women, 326 men). All of them are residents of Novosibirsk region. SNPs were genotyped by allele-specific PCR. RESULTS: The age distributions of our male and female patients were found to be significantly different. For men, the distribution has two maxima, whereas for women it has only one maximum, which is between the two. This fact stimulated us to perform a sex-specific analysis. No statistically significant difference has been found between distributions of the three genes in our PE patients and healthy controls. However, it was discovered that the TT genotype of MTHFR: 677 C>T polymorphism in men increases the risk of PE in comparison to controls. In fact, the difference increases in the age group over 45years. Also, AA genotype of MTRR 66 A>G polymorphism in women below 45years decreases the risk of PE. The sex-specific multiple linear regression analysis gave us estimates of the relative PE risk associated with MTHFR 677 C>T, F2: 20210G>A (Prothrombin), and F5: 1691G>A (Leiden) mutations.


Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Ferredoxina-NADP Reductasa/genética , Ácido Fólico/metabolismo , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo de Nucleótido Simple , Embolia Pulmonar/genética , Adulto , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Homocisteína/sangre , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Mutación , Reacción en Cadena de la Polimerasa , Probabilidad , Siberia
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