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1.
Langmuir ; 34(1): 205-212, 2018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29249149

RESUMEN

Compartmentalized microcapsules are useful for the release of multiple cargos in medicine, agriculture, and advanced responsive materials. Although several encapsulation strategies that involve more than one cargo have been proposed, dual- or multicompartment capsules with high cargo loadings and sufficient mechanical stability are rarely reported. Here, we propose a single-step emulsification route for the preparation of strong dual-compartment capsules that can host the main cargo in their core in combination with another liquid cargo stored within their thick shell. Capsules are produced through the polymerization of the middle oil phase of water-oil-water double emulsions made by microfluidics. Compartmentalization results from the phase separation of monomers within the middle phase of the double emulsion. We investigate the effect of such phase separation process on the microstructure and mechanical properties of the capsules and eventually illustrate the potential of this approach by creating thermosensitive capsules with programmable bursting temperature. The large variety of possible mixtures of monomers and cargos that can be added in the oil and aqueous phases of the double emulsion templates makes this encapsulation approach a promising route for the fabrication of robust microcapsules for on-demand release of multiple cargos.

2.
Langmuir ; 33(9): 2402-2410, 2017 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-28195737

RESUMEN

Microcapsules for controlled chemical release and uptake are important in many industrial applications but are often difficult to produce with the desired combination of high mechanical strength and high shell permeability. Using water-oil-water double emulsions made in microfluidic devices as templates, we developed a processing route to obtain mechanically robust microcapsules exhibiting a porous shell structure with controlled permeability. The porous shell consists of a network of interconnected polymer particles that are formed upon phase separation within the oil phase of the double emulsion. Porosity is generated by an inert diluent incorporated in the oil phase. The use of undecanol and butanol as inert diluents allows for the preparation of microcapsules covering a wide range of shell-porosity and force-at-break values. We found that the amount and chemical nature of the diluent influence the shell porous structure by changing the mechanism of phase separation that occurs during polymerization. In a proof-of-concept experiment, we demonstrate that the mechanically robust microcapsules prepared through this simple approach can be utilized for the on-demand release of small molecules using a pH change as exemplary chemical trigger.

3.
Am J Prev Cardiol ; 18: 100675, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38694728

RESUMEN

Cardiovascular disease (CVD) remains the leading cause of death worldwide. The risk of a cardiovascular (CV) event is not static and increases along a continuum, making identification and management complex. Aspirin has been the cornerstone of antiplatelet therapy in CV risk reduction and remains the only antiplatelet agent with current guideline recommendations throughout the CV risk continuum. In light of recent trials, the role of aspirin in CVD prevention in asymptomatic patients has been downgraded in clinical guidelines. However, a substantial proportion of asymptomatic patients have underlying conditions, such as advanced subclinical atherosclerosis that are associated with high CV risk. Advanced subclinical atherosclerosis has not been extensively investigated in patients in clinical trials but in the absence of significant bleeding risks, patients with subclinical atherosclerosis may particularly benefit from preventive aspirin therapy. Recent studies and clinical guidelines support the need for a personalized treatment approach for these patients, balancing their risk of future CV events against their relative bleeding risk. In this commentary, we first discussed various tools and strategies currently available for assessing CV and bleeding risks; we then provided two hypothetical cases to outline how these tools can be implemented for optimal management of patients with no prior CV events who, nonetheless, are susceptible to CVD. The first case details a young and apparently healthy patient with underlying advanced subclinical atherosclerosis; whereas the second case describes a patient with recently diagnosed type 2 diabetes mellitus who is at higher risk of CVD than their non-diabetic counterparts. For both cases, we considered patient clinical characteristics, CV and bleeding risks, as well as other risk factors to evaluate the appropriate treatment strategy and determine whether patients would obtain a net clinical benefit from low-dose aspirin therapy. These cases can serve as examples to guide clinical decision-making on the use of low-dose aspirin for primary CVD prevention and improve CVD management via a personalized approach.

4.
J Am Heart Assoc ; 13(12): e034718, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38860391

RESUMEN

BACKGROUND: Coronary artery calcium testing using noncontrast cardiac computed tomography is a guideline-indicated test to help refine eligibility for aspirin in primary prevention. However, access to cardiac computed tomography remains limited, with carotid ultrasound used much more often internationally. We sought to update the role of aspirin allocation in primary prevention as a function of subclinical carotid atherosclerosis. METHODS AND RESULTS: The study included 11 379 participants from the MESA (Multi-Ethnic Study of Atherosclerosis) and ARIC (Atherosclerosis Risk in Communities) studies. A harmonized carotid plaque score (range, 0-6) was derived using the number of anatomic sites with plaque from the left and right common, bifurcation, and internal carotid artery on ultrasound. The 5-year number needed to treat and number needed to harm as a function of the carotid plaque score were calculated by applying a 12% relative risk reduction in atherosclerotic cardiovascular disease (ASCVD) events and 42% relative increase in major bleeding events related to aspirin use, respectively. The mean age was 57 years, 57% were women, 23% were Black, and the median 10-year ASCVD risk was 12.8%. The 5-year incidence rates (per 1000 person-years) were 5.5 (4.9-6.2) for ASCVD and 1.8 (1.5-2.2) for major bleeding events. The overall 5-year number needed to treat with aspirin was 306 but was 2-fold lower for individuals with carotid plaque versus those without carotid plaque (212 versus 448). The 5-year number needed to treat was less than the 5-year number needed to harm when the carotid plaque score was ≥2 for individuals with ASCVD risk 5% to 20%, whereas the presence of any carotid plaque demarcated a favorable risk-benefit for individuals with ASCVD risk >20%. CONCLUSIONS: Quantification of subclinical carotid atherosclerosis can help improve the allocation of aspirin therapy.


Asunto(s)
Aspirina , Enfermedades de las Arterias Carótidas , Placa Aterosclerótica , Prevención Primaria , Humanos , Aspirina/uso terapéutico , Femenino , Masculino , Persona de Mediana Edad , Prevención Primaria/métodos , Placa Aterosclerótica/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/etnología , Enfermedades de las Arterias Carótidas/epidemiología , Enfermedades de las Arterias Carótidas/prevención & control , Anciano , Medición de Riesgo , Estados Unidos/epidemiología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Arterias Carótidas/diagnóstico por imagen , Ultrasonografía , Factores de Riesgo , Etnicidad , Anciano de 80 o más Años , Ultrasonografía de las Arterias Carótidas
5.
Maturitas ; 50(3): 189-95, 2005 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-15734600

RESUMEN

OBJECTIVE: The present study was undertaken to assess the impact, effectiveness and safety of a monophasic hormone replacement treatment (HRT) for continuous use with regards to the clinical effects, bleeding patterns and lipid profile of menopausal women in four Latin American countries. DESIGN: Three hundred and six postmenopausal women with natural menopause and uterus present were recruited. This was a multicentre prospective, clinical trial; the participating countries were Brazil (BR), Colombia (CO), Mexico (MX) and Argentina (AR). The study period was 12 months. The HRT regime was formulated in tablets containing 2 mg estradiol E2 and 1mg norethisterone acetate (NETA); one visit every 3 months was solicited. METHODS: HRT was given as one tablet every day without interruption for 1 year. Climacteric complaints, side-effects, reason for discontinuation, bleeding patterns, lipid profile at baseline and 12 months of treatment were documented. RESULTS: There were no significant differences between the four populations on clinical measurements. Thirty-four women discontinued, 13 for bleeding problems. The five most common side-effects were mastalgia, bleeding problems, headache, pelvic pain and nausea. 44.8% of women experienced scanty vaginal bleeding during the first 3 months of therapy. Ninety seven percent of women had amenorrhea at the end of the study in MX, BR and AR, and 100% in CO. Body weight was constant during the study, and no correlation was found between body weight and total days with bleeding. The Kupperman index score was used to evaluate the climacteric complaints, and the score decreased from a mean of 25.4 to 5.1 at 12-months visit. Total cholesterol levels were significantly reduced in BR and CO (P < 0.05) between baseline and the final sample; serum triglycerides remained unchanged, HDL-cholesterol was significantly increased in MX (P < 0.05), and LDL-cholesterol was significantly reduced in CO (P < 0.05). The results of this 1-year study emphasize that a continuous combined HRT regimen with 2 mg E2/1 mg NETA is an attractive alternative for postmenopausal women who are at least 1 year after their menopause and optimally 2 years after their menopause. Although the combination of 2 mg E2 with 1 mg NETA in a continuous combined therapy scheme has been in use in the Nordic countries for over a decade and in Latin America for the last 6 years, there have been no previous published reports on its effectivity in Latin American women. This publication reports the experience in a group of 306 Latin American women, and it is the first Latin American publication with this formulation.


Asunto(s)
Anticonceptivos Sintéticos Orales/uso terapéutico , Estradiol/uso terapéutico , Terapia de Reemplazo de Estrógeno , Menopausia , Noretindrona/análogos & derivados , Noretindrona/uso terapéutico , Administración Oral , Adulto , Ansiedad/tratamiento farmacológico , Anticonceptivos Sintéticos Orales/efectos adversos , Depresión/tratamiento farmacológico , Mareo/tratamiento farmacológico , Estradiol/efectos adversos , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Cefalea/tratamiento farmacológico , Frecuencia Cardíaca/efectos de los fármacos , Sofocos/tratamiento farmacológico , Humanos , América Latina , Lípidos/sangre , Persona de Mediana Edad , Debilidad Muscular/tratamiento farmacológico , Noretindrona/efectos adversos , Acetato de Noretindrona , Parestesia/tratamiento farmacológico , Estudios Prospectivos
6.
Contraception ; 67(5): 367-72, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12742559

RESUMEN

This prospective, multicenter study was conducted to evaluate the contraceptive reliability, cycle control and tolerability of a 21-day oral contraceptive regimen containing 20 microg ethinylestradiol and 75 microg gestodene in four Latin American countries (Mexico, Argentina, Brazil and Colombia). Participants took trial medication daily for 21 days. Contraceptive efficacy, cycle control and tolerability were evaluated over a period of 13 cycles. Efficacy data gathered from 5,109 treatment cycles were obtained from 393 participants. The trial medication proved to be an effective contraceptive and provided good cycle control. One pregnancy because of poor compliance was recorded. This resulted in a study Pearl index of 0.25. Forty-six percent of Latin American women reported one intracyclic spotting bleeding episode and 37.6% reported one intracyclic breakthrough bleeding (medium/excessive bleeding) episode during cycles 2-4 (primary target). Overall, intracyclic bleeding was reported in 41%. Overall, there was a trend towards a lower incidence of spotting in all the countries and this difference had statistical significance between Argentina and the others three countries (p < 0.05) during cycles 2-4. This trend was also apparent with respect to breakthrough bleeding, but again the difference did not achieve statistical significance. The discontinuation rate because of adverse events was low (3%); no serious adverse events were reported. More than 78% of the women in the four countries maintained constant body weight or lost weight (2 kg) during the study. The treatment effect on blood pressure was negligible. There were no appreciable changes in mean laboratory values over the course of the study.


Asunto(s)
Anticonceptivos Orales Combinados/administración & dosificación , Etinilestradiol/administración & dosificación , Norpregnenos/administración & dosificación , Cooperación del Paciente , Adolescente , Adulto , Argentina , Brasil , Colombia , Anticonceptivos Orales Combinados/efectos adversos , Esquema de Medicación , Femenino , Humanos , México , Estudios Prospectivos
8.
Eur J Hum Genet ; 17(9): 1154-9, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19259128

RESUMEN

Duplication within the chromosome 17p11.2 (CMT1Adup), peripheral myelin protein 22 (PMP22), myelin protein zero (MPZ) and gap junction beta1-protein (GJB1) gene mutations are frequent causes of the Charcot-Marie-Tooth disease (CMT). A large number of mutations in these genes are listed in databases. Sequence variants identified in patients are frequently reported as mutations without further evaluation. We analyzed 250 consecutively recruited unrelated Austrian CMT patients for CMT1Adup by microsatellite marker typing, real-time PCR or MLPA, and found 79 duplications (31.6%). The coding regions of the PMP22, MPZ and GJB1 genes were analyzed by direct sequencing in the remaining patients; 28 patients showed mutations, 14 of which were novel. We scored the pathogenicity of novel missense mutations by segregation studies and by their exclusion in control samples. Our comprehensive literature study found that up to 60% of the reported mutations in these genes had not been evaluated regarding their pathogenicity, and the PANTHER bioinformatics tool was used to score novel and published missense variants. The PANTHER program scored known polymorphisms as such, but scored approximately 82-88% only of the published and novel mutations as most likely deleterious. Mutations associated with axonal CMT were less likely to be classified as deleterious, and the PMP22 S72L mutation repeatedly associated with severe CMT was classified as a polymorphism using default parameters. Our data suggest that this in silico analysis tool could be useful for assessing the functional impact of DNA variations only as a complementary approach. The CMT1Adup, GJB1, MPZ and PMP22 mutation frequencies were in the range of those described in other CMT patient collectives with different ethnical backgrounds.


Asunto(s)
Biología Computacional/métodos , Conexinas/genética , Mutación , Proteína P0 de la Mielina/genética , Proteínas de la Mielina/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Austria , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/patología , Análisis Mutacional de ADN , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Proteína beta1 de Unión Comunicante
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