18 research outputs found

    Coexistence and management of abdominal aortic aneurysm and coronary artery disease

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    Background: Abdominal aortic aneurysm (AAA) and coronary atherosclerosis share common risk factors. In this study, a single-center management experience of patients with a coexistence of AAA and coronary artery disease (CAD) is presented.Methods: 271 consecutive patients who underwent elective AAA repair were reviewed. Coronary imaging in 118 patients was considered suitable for exploration of AAA coexistence with CAD.Results: Significant coronary stenosis (> 70%) were found in 65.3% of patients. History of cardiac revascularization was present in 26.3% of patients, myocardial infarction (MI) in 31.4%, and 39.8% had both. In a subgroup analysis, prior history of percutaneous coronary intervention (PCI) (OR = 6.9, 95% CI 2.6–18.2, p < 0.001) and patients’ age (OR = 1.1, 95% CI 1.0–1.2, p = 0.007) were independent predictors of significant coronary stenosis. Only 52.0% (40/77) of patients with significant coronary stenosis underwent immediate coronary revascularization prior to aneurysm repair: PCI in 32 cases (4 drug-eluting stents and 27 bare metal stents), coronary artery bypass graft in 8 cases. Patients undergoing revascularization prior to surgery had longer mean time from coronary imaging to AAA repair (123.6 vs. 58.1 days, p < 0.001). Patients undergoing coronary artery evaluation prior to AAA repair had shorter median hospitalization (7 [2–70] vs. 7 [3–181] days, p = 0.007) and intensive care unit stay (1 [0–9] vs. 1 [0–70] days, p = 0.014) and also had a lower rate of major adverse cardiovascular events or multiple organ failure (0% vs. 3.9%, p = 0.035). A total of 11.0% of patients had coronary artery aneurysms.Conclusions: Patients with AAA might benefit from an early coronary artery evaluation strategy

    How does the CO2 in supercritical state affect the properties of drug-polymer systems, dissolution performance and characteristics of tablets containing bicalutamide?

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    The increasing demand for novel drug formulations has caused the introduction of the supercritical fluid technology, CO2 in particular, into pharmaceutical technology as a method enabling the reduction of particle size and the formation of inclusion complexes and solid dispersions. In this paper, we describe the application of scCO2 in the preparation of binary systems containing poorly soluble antiandrogenic drug bicalutamide and polymeric excipients, either Macrogol 6000 or Poloxamer®407. The changes in the particle size and morphology were followed using scanning electron microscopy and laser di raction measurements. Di erential scanning calorimetry was applied to assess thermal properties, while X-ray powder di ractometry was used to determine the changes in the crystal structure of the systems. The dissolution of bicalutamide was also considered. Binary solid dispersions were further compressed, and the attributes of tablets were assessed. Tablets were analyzed directly after manufacturing and storage in climate chambers. The obtained results indicate that the use of supercritical CO2 led to the morphological changes of particles and the improvement of drug dissolution. The flowability of blends containing processed binary systems was poor; however, they were successfully compressed into tablets exhibiting enhanced drug release

    Compression-Induced Phase Transitions of Bicalutamide

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    The formation of solid dispersions with the amorphous drug dispersed in the polymeric matrix improves the dissolution characteristics of poorly soluble drugs. Although they provide an improved absorption after oral administration, the recrystallization, which can occur upon absorption of moisture or during solidification and other formulation stages, serves as a major challenge. This work aims at understanding the amorphization-recrystallization changes of bicalutamide. Amorphous solid dispersions with poly(vinylpyrrolidone-co-vinyl acetate) (PVP/VA) were obtained by either ball milling or spray drying. The applied processes led to drug amorphization as confirmed using X-ray diffraction and differential scanning calorimetry. Due to a high propensity towards mechanical activation, the changes of the crystal structure of physical blends of active pharmaceutical ingredient (API) and polymer upon pressure were also examined. The compression led to drug amorphization or transition from form I to form II polymorph, depending on the composition and applied force. The formation of hydrogen bonds confirmed using infrared spectroscopy and high miscibility of drug and polymer determined using non-isothermal dielectric measurements contributed to the high stability of amorphous solid dispersions. They exhibited improved wettability and dissolution enhanced by 2.5- to 11-fold in comparison with the crystalline drug. The drug remained amorphous upon compression when the content of PVP/VA in solid dispersions exceeded 20% or 33%, in the case of spray-dried and milled systems, respectively.Polish National Science Centre 2015/16/W/NZ7/0040

    Temporal changes in the pattern of invasive angiography use and its outcome in suspected coronary artery disease : implications for patient management and healthcare resource utilization

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    Introduction: Invasive coronary angiography (CAG), the ‘gold standard’ in coronary artery disease (CAD) diagnosis, requires hospitalization, is not risk-free, and engages considerable healthcare resources. Aim: To assess recent (throught out 10 years) evolution of ‘significant’ (≥ 50% stenosis(es)) CAD prevalence in subjects undergoing CAG for CAD diagnosis in a high-volume tertiary referral center. Material and methods: Anonymized medical records were compared from the last vs. the first 2-years of the decade (June 2007 to May 2018). Referrals for suspected CAD were 2067 of 4522 hospitalizations (45.7%) and 1755 of 5196 (33.8%) respectively (p < 0.001). Results: The median patient age (64 vs. 68 years) and the prevalence of heart failure (24.1% vs. 42.2%) increased significantly (p < 0.001). The CAG atherosclerotic lesions, for all stenosis categories (< 50%; ≥ 50%; ≥ 70%; occlusion(s)), were significantly more prevalent in men. The proportion of subjects with any atherosclerosis on CAG increased (80.7% vs. 77.6%, p = 0.015). However, in the absence of any gross change in, for instance, the fraction of women (40.4% vs. 41.8%), the proportion of CAGs with significant CAD (lesion(s) ≥ 50%) decreased from 55.2% in 2007/2008 to below 1 in every 2 angiograms (48.9%) in 2017/2018 (p < 0.001). This unexpected finding occurred consistently across nearly all CAG referral categories. Conclusions: Despite more advanced age and a higher proportion of subjects with ‘any’ coronary atherosclerosis on CAG, the likelihood of a ‘negative’ angiogram (lesion(s) < 50%; no further evaluation/intervention) has increased significantly over the last decade. The exact nature of this phenomenon requires further investigation, particularly as a reverse trend would be expected with the growing role (and current high penetration) of contemporary non-invasive diagnostic tools to rule out significant CAD

    Influence of Polymeric Additive on the Physical Stability and Viscoelastic Properties of Aripiprazole

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    In this article, we investigated aripiprazole + Kollidon VA64 (ARP/KVA) and aripiprazole + Soluplus (ARP/SOP) amorphous solid dispersions. Thermal properties of all prepared systems have been examined by means of differential scanning calorimetry (DSC). Compositions revealing the recrystallization tendency were subsequently investigated by means of broadband dielectric spectroscopy (BDS). On the basis of dielectric data, the physically stable drug–polymer concentrations have been found. Finally, these systems have been investigated by rheology, which enables us to determine the minimal temperature required for dissolving the drug in the polymeric matrix, as well as the temperature dependence of the sample viscosity. Our investigations have shown that the amorphous form of the investigated antipsychotic drug might be effectively stabilized by both employed polymers. However, due to the better stabilization effect and the more favorable rheological properties, KVA proved to be a better polymeric excipient for extrusion of amorphous aripiprazole

    The effect of silica-calcite sedimentary rock contained in the chicken broiler diet on the overall quality of chicken muscles

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    Opoka is a silica-calcite sedimentary rock chemically and structurally similar to diatomaceous earth (DE), composed mainly of silicon dioxide (SiO2), calcium carbonate (CaCO3), amorphous SiO. Opoka occurs predominantly in South Eastern Europe and Russia. Due to these specific properties investigation on the effect of opoka-enriched diet on chemical composition and overall quality of breast and leg muscles of broilers was initiated. Working samples showed a statistically significant increase in ash content or water content and a decrease in lipid content in the leg muscles of both male and female broilers (P<0.01). Furthermore, the addition of opoka to the diet increased WHC of leg muscles in females and hardness or chewiness of these muscles in both genders (P<0.05). The supplementation of broiler diet with opoka can be effectively applied to modify texture features of leg and breast muscle tissue which might, in turn, serve to regulate the nutritional and technological value of chicken meat

    The Self-Assembly Phenomenon of Poloxamers and Its Effect on the Dissolution of a Poorly Soluble Drug from Solid Dispersions Obtained by Solvent Methods

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    The self-assembly phenomenon of amphiphiles has attracted particular attention in recent years due to its wide range of applications. The formation of nanoassemblies able to solubilize sparingly water-soluble drugs was found to be a strategy to solve the problem of poor solubility of active pharmaceutical ingredients. Binary and ternary solid dispersions containing Biopharmaceutics Classification System (BCS) class II drug bicalutamide and either Poloxamer&reg;188 or Poloxamer&reg;407 as the surface active agents were obtained by either spray drying or solvent evaporation under reduced pressure. Both processes led to morphological changes and a reduction of particle size, as confirmed by scanning electron microscopy and laser diffraction measurements. The increase in powder wettability was confirmed by means of contact angle measurements. The effect of an alteration of the crystal structure was followed by powder X-ray diffractometry while thermal properties were determined using differential scanning calorimetry. Interestingly, bicalutamide exhibited a polymorph transition after spray drying with the poloxamer and polyvinylpyrrolidone (PVP), while the poloxamer underwent partial amorphization. Moreover, due to the surface activity of the carrier, the solid dispersions formed nanoaggregates in water, as confirmed using dynamic light scattering measurements. The aggregates measuring 200&ndash;300 nm in diameter were able to solubilize bicalutamide inside the hydrophobic inner parts. The self-assembly of binary systems was found to improve the amount of dissolved bicalutamide by 4- to 8-fold in comparison to untreated drug. The improvement in drug dissolution was correlated with the solubilization of poorly soluble molecules by macromolecules, as assessed using emission spectroscopy
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