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1.
Medicina (Kaunas) ; 55(7)2019 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-31248007

RESUMEN

Background and Objectives: Oral anticoagulation (OAC) is widely used in daily clinical practice worldwide for various indications. We aimed to explore the perception of Bulgarian clinicians about their patients' attitude and knowledge of long-term OAC, prescribed for atrial fibrillation (AF) and/or known deep venous thrombosis (DVT)/pulmonary embolism (PE). Materials and Methods: We performed a cross-sectional study that involved 226 specialists: 187 (82.7%) cardiologists, 23 (10.2%) neurologists, and 16 (7.1%) vascular surgeons. They filled in a questionnaire, specially designed for our study, answering various questions regarding OAC treatment in their daily clinical practice. Results: The mean prescription rate of OACs in AF patients was 80.3% and in DVT/PE-88.6%. One hundred and eighty-seven (82.7%) of the participants stated they see their patients on OAC at least once per month. According to more than one-third of the inquired clinicians, the patients did not understand well enough the provided information concerning net clinical benefit of OAC treatment. About 68% of the clinicians declared that their patients would prefer a "mutual" approach, discussing with the physician the OAC options and taking together the final decision, whereas according to 43 (19.0%), the patients preferred the physician to take a decision for them. Patients' OAC treatment had been interrupted at least once within the last year due to a physician's decision by 178 (78.8%) of the participants and the most common reason was elective surgery. The most influential factors for a patient's choice of OAC were the need of a specific diet to be kept, intake frequency, and possible adverse reactions. Conclusions: Our results suggest that a clinician's continuous medical education, shared decision-making, and appropriate local strategies for improved awareness of AF/DVT/PE patients are key factors for improvement of OAC management.


Asunto(s)
Anticoagulantes/normas , Alfabetización en Salud/normas , Pacientes/psicología , Percepción , Médicos/psicología , Administración Oral , Adulto , Análisis de Varianza , Anticoagulantes/uso terapéutico , Actitud del Personal de Salud , Bulgaria , Estudios Transversales , Femenino , Alfabetización en Salud/métodos , Humanos , Masculino , Persona de Mediana Edad , Pacientes/estadística & datos numéricos , Médicos/estadística & datos numéricos , Estadísticas no Paramétricas
2.
Langmuir ; 34(16): 4897-4907, 2018 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-29627989

RESUMEN

Here, we have investigated the synergistic growth of long wormlike micelles and their transformation into disklike micelles, which occurs in three-component solutions composed of sodium lauryl ether sulfate (SLES; anionic), cocamidopropyl betaine (CAPB; zwitterionic), and dodecanoic acid (HC12; nonionic). The solution rheology is characterized in terms of zero-shear viscosities and characteristic times for micellar breaking and reptation. Furthermore, the microstructure evolution, leading to the observed rheological behavior, is revealed by cryo-transmission electron microscopy (TEM) micrographs. In all cases, the CAPB-to-SLES ratio is fixed, whereas the fatty acid concentration is varied. At a certain HC12 concentration, the solution viscosity passes through a maximum. The cryo-TEM imaging indicates that wormlike micelles appear before the peak, grow further up to the peak, and finally transform into disklike aggregates (a very rare micellar structure) after the peak. The transformation of worms into disks leads to a drop in viscosity because the length-to-thickness aspect ratio of the disks is significantly lower than that of the worms. In this article, we elucidate the structure-rheology relations in micellar solutions that might be applied for the design of personal-care and household formulations.

3.
J Biol Chem ; 291(7): 3639-47, 2016 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-26683377

RESUMEN

In breast tumors, activation of the nuclear factor κB (NFκB) pathway promotes survival, migration, invasion, angiogenesis, stem cell-like properties, and resistance to therapy--all phenotypes of aggressive disease where therapy options remain limited. Adding an anti-inflammatory/anti-NFκB agent to breast cancer treatment would be beneficial, but no such drug is approved as either a monotherapy or adjuvant therapy. To address this need, we examined whether dimethyl fumarate (DMF), an anti-inflammatory drug already in clinical use for multiple sclerosis, can inhibit the NFκB pathway. We found that DMF effectively blocks NFκB activity in multiple breast cancer cell lines and abrogates NFκB-dependent mammosphere formation, indicating that DMF has anti-cancer stem cell properties. In addition, DMF inhibits cell proliferation and significantly impairs xenograft tumor growth. Mechanistically, DMF prevents p65 nuclear translocation and attenuates its DNA binding activity but has no effect on upstream proteins in the NFκB pathway. Dimethyl succinate, the inactive analog of DMF that lacks the electrophilic double bond of fumarate, is unable to inhibit NFκB activity. Also, the cell-permeable thiol N-acetyl l-cysteine, reverses DMF inhibition of the NFκB pathway, supporting the notion that the electrophile, DMF, acts via covalent modification. To determine whether DMF interacts directly with p65, we synthesized and used a novel chemical probe of DMF by incorporating an alkyne functionality and found that DMF covalently modifies p65, with cysteine 38 being essential for the activity of DMF. These results establish DMF as an NFκB inhibitor with anti-tumor activity that may add therapeutic value in the treatment of aggressive breast cancers.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Dimetilfumarato/farmacología , FN-kappa B/antagonistas & inhibidores , Proteínas de Neoplasias/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Factor de Transcripción ReIA/antagonistas & inhibidores , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisteína/química , Dimetilfumarato/química , Dimetilfumarato/uso terapéutico , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes Reporteros/efectos de los fármacos , Humanos , Ratones Desnudos , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Distribución Aleatoria , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/metabolismo , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Langmuir ; 32(48): 12885-12893, 2016 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-27934523

RESUMEN

The synergistic growth of giant wormlike micelles in ternary mixed solutions composed of an anionic surfactant (sodium laurylethersulfate, SLES), a zwitterionic surfactant (cocamidopropyl betaine, CAPB), and octanoic acid (HC8) is studied. Rheological data and their analysis in terms of Cole-Cole plots and micellar characteristic times are presented, and the micellar structures behind the observed rheological behavior are revealed by cryo-TEM micrographs. The surfactant composition is fixed near the maximal micelle size of the binary SLES + CAPB system, whereas the concentration of HC8 is varied. At a given HC8 concentration, the viscosity of the ternary micellar solutions exhibits a very high and sharp peak. Polarized-light optical microscopy indicates that all investigated solutions are isotropic rather than liquid-crystalline. The cryo-TEM imaging shows complex phase behavior: wormlike micelles to the left of the peak, giant entangled wormlike micelles at the peak, and long wormlike micelles coexisting with multiconnected micellar aggregates to the right of the peak. The formation of multiconnected micelles leads to a drop in viscosity at the higher concentrations. The results contribute to a better understanding of the structure-rheology relations in micellar surfactant solutions and could be useful for controlling the properties of formulations in personal-care and house-hold detergency.

5.
Immun Inflamm Dis ; 12(5): e1273, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38798123

RESUMEN

BACKGROUND: Previous research done in Bulgaria demonstrated a fivefold reduction in mortality from COVID-19 with increased doses of colchicine from two hospitals in the country. We report here a further 333 cases of COVID-19 inpatients, treated with different doses of colchicine and its effect on mortality. MATERIALS AND METHODS: A case-control comparison from two additional hospitals was conducted between increased doses of colchicine and added bromhexine to standard of care (SOC) versus current SOC. Risk and odds ratio, as well as subgroup analysis, was conducted with newly reported data, alongside aggregate data from all hospital centers to determine the extent of mortality reduction in COVID-19 inpatients. RESULTS: There was a clear reduction in the mortality of inpatients with increasing doses of colchicine-between twofold and sevenfold. Colchicine loading doses of 4 mg are more effective than those with 2 mg. Despite these doses being higher than the so-called "standard doses," colchicine inpatients experienced lower mortality than SOC patients (5.7% vs. 19.53%). This mortality benefit was evident in different age subgroups, with a 4-mg loading dose of colchicine proving slightly superior to a 2-mg loading dose. Colchicine led to an overall relative risk reduction of 70.7%, with SOC patients having 3.91 higher odds of death. The safety of the doses was not different than the reported in the summary of product characteristics. CONCLUSION: Inpatients in Bulgaria with added colchicine and bromhexine to SOC achieved better clinical and mortality outcomes than those on SOC alone. These results question the World Health Organization-recommended strategy to inhibit viral replication. We posit that our treatment strategy to inhibit the Severe acute respiratory syndrome coronavirus 2 entry into the cell with inhaled bromhexine and the hyperactivated NLRP3 inflammasome with higher doses of colchicine, prevents the development of cytokine storm. The timing of the initiation of treatment seems critical.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Colchicina , SARS-CoV-2 , Humanos , Colchicina/administración & dosificación , Colchicina/uso terapéutico , Femenino , Persona de Mediana Edad , Masculino , Anciano , COVID-19/mortalidad , COVID-19/epidemiología , Estudios de Casos y Controles , Adulto , Anciano de 80 o más Años , Bulgaria/epidemiología , Pacientes Internos , Relación Dosis-Respuesta a Droga , Resultado del Tratamiento
6.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): m1023, 2008 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-21203015

RESUMEN

The title compound, cis,fac-dichloridotetra-kis(dimethyl sulfoxide)-κ(3)S,κO-ruthenium(II), [RuCl(2)(C(2)H(6)OS)(4)], was obtained from newly synthesized ruthenium complexes of 3-amino-2-chloro-pyridine. The Ru atom has a distorted octa-hedral coordination with two cis-oriented chloride ligands and four dimethyl sulfoxide ligands. Three of the sulfoxide ligands are S-bonded in a fac configuration, while the fourth is O-bonded. The title compound represents a new, and fourth, polymorph of the complex. Two other monoclinic forms and an ortho-rhom-bic modification have been reported previously.

7.
J Vis Exp ; (119)2017 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-28190074

RESUMEN

Inflammation is a cancer hallmark that underlies cancer incidence and promotion, and eventually progression to metastasis. Therefore, adding an anti-inflammatory drug to standard cancer regiments may improve patient outcome. One such drug, aspirin (acetylsalicylic acid, ASA), has been explored for cancer chemoprevention and anti-tumor activity. Besides inhibiting the cyclooxygenase 2-prostaglandin axis, ASA's anti-cancer activities have also been attributed to nuclear factor ĸB (NFĸB) inhibition. Because prolonged ASA use may cause gastrointestinal toxicity, a prodrug strategy has been implemented successfully. In this prodrug design the carboxylic acid of ASA is masked and additional pharmacophores are incorporated. This protocol describes how we synthesized an aspirin-fumarate prodrug, GTCpFE, and characterized its inhibition of the NFĸB pathway in breast cancer cells and attenuation of the cancer stem-like properties, an important NFĸB-dependent phenotype. GTCpFE effectively inhibits the NFĸB pathway in breast cancer cell lines whereas ASA lacks any inhibitory activity, indicating that adding fumarate to ASA structure significantly contributes to its activity. In addition, GTCpFE shows significant anti-cancer stem cell activity by blocking mammosphere formation and attenuating the cancer stem cell associated CD44+CD24- immunophenotype. These results establish a viable strategy to develop improved anti-inflammatory drugs for chemoprevention and cancer therapy.


Asunto(s)
Aspirina/farmacología , Neoplasias de la Mama/patología , Fumaratos/farmacología , Subunidad p50 de NF-kappa B/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Profármacos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Regulación de la Expresión Génica , Humanos , Células Madre Neoplásicas/patología , Profármacos/síntesis química , Transducción de Señal/efectos de los fármacos
8.
J Colloid Interface Sci ; 449: 46-61, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25315407

RESUMEN

By analysis of experimental data, a quantitative theoretical interpretation of the solubility limit of medium- and long-chain fatty alcohols in micellar solutions of water-soluble surfactants is presented. A general picture of the phase behavior of the investigated systems is given in the form of phase diagrams. The limited solubility of the fatty alcohols in the micelles of conventional surfactants is explained with the precipitation of their monomers in the bulk, rather than with micelle phase separation. The long chain fatty alcohols (with n=14, 16 and 18 carbon atoms) exhibit an ideal mixing in the micelles of the anionic surfactant sodium laurylethersulfate (SLES) and the zwitterionic surfactant cocamidopropyl betaine (CAPB) at temperatures of 25, 30, 35 and 40 °C. Deviations from ideality are observed for the alcohols of shorter chain (n=10 and 12), which can be explained by a mismatch with the longer chains of the surfactant molecules. Using the determined thermodynamic parameters of the systems, their phase diagrams are constructed. Such a diagram consists of four domains, viz. mixed micelles; coexistent micelles and precipitate (dispersed crystallites or droplets); precipitate without micelles, and molecular solution. The four boundary lines intersect in a quadruple point, Q. For ionic surfactants (like SLES), a detailed theory for calculating the boundary lines of the phase diagrams is developed and verified against data for the positions of the kinks in surface tension isotherms. The theory takes into account the electrostatic interactions in the micellar solutions and the effect of counterion binding. The results can be useful for a quantitative interpretation and prediction of the phase behavior of mixed solutions of two (or more) surfactants, one of them being water soluble and forming micelles, whereas the other one has a limited water solubility, but readily forms mixed micelles with the former surfactant.

9.
J Colloid Interface Sci ; 416: 258-73, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24370430

RESUMEN

Here, we present a detailed theoretical model describing the growth of disclike surfactant micelles. The model is tested against light-scattering data for micellar solutions from mixed conventional surfactants and from fluorinated surfactants. Theoretical expressions are derived for the concentration dependencies of the number and mass average aggregation numbers. Central role in the theory is played by the difference between the chemical potentials of a surfactant molecule in cylindrical and discoidal micelles. This difference, scaled with the thermal energy kT, is denoted p. For p<0, the formation of cylindrical (rather than disclike) micelles is energetically favored. For p>0 disclike micelles are formed, but their growth is limited due to the rise of their positive peripheral energy. Because of that, disclike micelles can be observed in a relatively narrow interval, 0

Asunto(s)
Modelos Estadísticos , Tensoactivos/química , Halogenación , Hidrodinámica , Luz , Micelas , Dispersión de Radiación , Soluciones , Termodinámica , Viscosidad
10.
J Colloid Interface Sci ; 369(1): 274-86, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22212739

RESUMEN

The limiting solubility of fatty acids in micellar solutions of the anionic surfactant sodium laurylethersulfate (SLES) and the zwitterionic surfactant cocamidopropyl betaine (CAPB) is experimentally determined. Saturated straight-chain fatty acids with n=10, 12, 14, 16, and 18 carbon atoms were investigated at working temperatures of 25, 30, 35, and 40°C. The rise of the fatty acid molar fraction in the micelles is accompanied by an increase in the equilibrium concentration of acid monomers in the aqueous phase. Theoretically, the solubility limit is explained with the precipitation of fatty acid crystallites when the monomer concentration reaches the solubility limit of the acid in pure water. In agreement with theory, the experiment shows that the solubility limit is proportional to the surfactant concentration. For ideal mixtures, the plot of the log of solubility limit vs. the chainlength, n, must be a straight line, which is fulfilled for n=14, 16, and 18. For the fatty acids of shorter chains, n=10 and 12, a deviation from linearity is observed, which is interpreted as non-ideal mixing due to a mismatch between the chainlengths of the surfactant and acid. The data analysis yields the solubilization energy and the interaction parameter for the fatty acid molecules in surfactant micelles. By using the determined parameter values, phase diagrams of the investigated mixed solutions are constructed. The four inter-domain boundary lines intersect in a quadruple point, whose coordinates have been determined. The results can be applied for the interpretation and prediction of the solubility, and phase behavior of medium- and long-chain fatty acids and other amphiphiles that are solubilizable in micellar surfactant solutions, as well as for determining the critical micellization concentration (CMC) of the respective mixed solution.

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