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1.
Int J Biol Macromol ; 251: 126531, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37634778

ABSTRACT

Developing a multifunctional biomaterial for bone filling and local antibiotic therapy is a complex challenge for bone tissue engineering. Hybrid nanocomposites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) with nanohydroxyapatite (nHA), fullerene (C60), and vancomycin (VC) were produced by injection. Fullerene was successfully impregnated with VC, as seen in FTIR. The crystallinity degree of PHBHV was slightly reduced in the presence of C60 and VC (64.3 versus 60.8 %), due to the plasticizing effect of these particles. It also resulted in a decrease in the glass transition temperature (Tg), observed by differential scanning calorimetry (DSC). Dense PHBHV/nHA/C60/VC had a flexural elastic modulus 29 % higher than PHBHV, as a result of the good interface between PHBHV, C60, and nHA - particles of high elastic modulus. Dense disks released 25.03 ± 4.27 % of VC for 14 days, which demonstrated its potential to be an alternative treatment to bone infections. Porous scaffolds of PHBHV/nHA/C60/VC were 3D printed with a porosity of 50 % and porous size of 467 ± 70 µm, and had compression elastic modulus of 0.022 GPa, being a promising material to trabecular bone replacement. The plasticizing effect of C60 improved the printability of the material. The hybrid nanocomposite was non-cytotoxic and showed good ability in adhering macrophage cells.

2.
Int J Biol Macromol ; 166: 448-458, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33127545

ABSTRACT

Poly-3-hydroxybutyrate (P(3HB)) and poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (P(3HB-co-3HHx)) are biocompatible and bioabsorbable biopolymers produced by different bacteria with potential for drug delivery in thermo-responsive magnetic microcarriers. Microparticles of P(3HB) and P(3HB-co-3HHx), with 5.85% mol of 3HHx, produced by Burkholderia sacchari, containing nanomagnetite (nM) and lipophilic hormone were prepared by simple emulsion (oil/water) technique leading to progesterone (Pg) encapsulation efficiency higher than 70% and magnetite loads of 3.1 and 2.3% (w/w) for P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg, respectively. These formulations were characterized by Infrared spectroscopy, X-ray diffraction, Thermal gravimetric analysis and Electron microscopy (TEM, SEM) techniques. The P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg microparticles presented spherical geometry with wrinkled surfaces and average size between 2 and 40 µm for 90% of the microparticles. The release profiles of the P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg formulations showed a hormone release trigger (6.9 and 11.1%, respectively) effect induced by oscillating external magnetic field (0.2 T), after 72 h. Progesterone release in non-magnetic tests with P(3HB-co-3HHx)/nM/Pg revealed a slight increment (5.6%) in relation to P(3HB)/nM/Pg. The experimental release of the P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg samples presented a good agreement with Higuchi model. The 3HHx comonomer content improves the hormone release of the P(3HB-co-3HHx)/nM/Pg formulation with potential for application to synchronize the estrous cycle.


Subject(s)
Drug Carriers/chemistry , Ferrosoferric Oxide/chemistry , Hydroxybutyrates/pharmacology , Nanoparticles/chemistry , Polyesters/pharmacology , Progesterone/pharmacology , Calorimetry, Differential Scanning , Crystallization , Emulsions/chemistry , Nanoparticles/ultrastructure , Oils/chemistry , Particle Size , Spectroscopy, Fourier Transform Infrared , Temperature , Thermogravimetry , Water/chemistry , X-Ray Diffraction
3.
Rev Esp Cardiol (Engl Ed) ; 74(10): 846-853, 2021 Oct.
Article in English, Spanish | MEDLINE | ID: mdl-33144125

ABSTRACT

INTRODUCTION AND OBJECTIVES: The ankle-brachial index (ABI) is an indicator of peripheral artery disease (PAD). The aim of this study was to assess the association between PAD, measured with the ABI, and cognitive function in persons with overweight or obesity and metabolic syndrome. METHODS: Cross-sectional study conducted with baseline data from the PREDIMED-Plus study, which included 4898 participants (after exclusion of those without ABI measurements) aged between 55 and 75 years, and with overweight or obesity and metabolic syndrome. At the baseline assessment, we measured the ABI with a standardized protocol and assessed the presence of other cardiovascular risk factors (eg, diabetes, dyslipidemia, hypertension). Cognitive function was evaluated using several tests validated for the Spanish population (mini-mental state examination [MMSE], phonological and semantic verbal fluency test, WAIS-III working memory index [WMI], parts A and B of the trail making test (TMT), and clock drawing test). Generalized linear models were used to assess the association between the ABI and cognitive function. RESULTS: Among the participants, 3.4% had PAD defined as ABI ≤ 0.9, and 3.3% had arterial calcification defined as ABI ≥ 1.4. PAD was associated with age, systolic blood pressure and obesity indicators, while arterial calcification was also associated with obesity and diabetes. No significant associations were observed between cognitive function and ABI or PAD. CONCLUSIONS: In our sample, the presence of PAD increased with age, blood pressure, and obesity. No significant association was observed between ABI, PAD, or cognitive function.


Subject(s)
Hypertension , Peripheral Arterial Disease , Aged , Ankle Brachial Index , Cognition , Cross-Sectional Studies , Humans , Middle Aged , Peripheral Arterial Disease/complications , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Risk Factors
4.
Atherosclerosis ; 314: 48-57, 2020 12.
Article in English | MEDLINE | ID: mdl-33160246

ABSTRACT

BACKGROUND AND AIMS: The aim of this study was to ascertain the association between the consumption of different categories of edible olive oils (virgin olive oils and olive oil) and olive pomace oil and ankle-brachial pressure index (ABI) in participants in the PREDIMED-Plus study, a trial of lifestyle modification for weight and cardiovascular event reduction in individuals with overweight/obesity harboring the metabolic syndrome. METHODS: We performed a cross-sectional analysis of the PREDIMED-Plus trial. Consumption of any category of olive oil and olive pomace oil was assessed through a validated food-frequency questionnaire. Multivariable linear regression models were fitted to assess associations between olive oil consumption and ABI. Additionally, ABI ≤1 was considered as the outcome in logistic models with different categories of olive oil and olive pomace oil as exposure. RESULTS: Among 4330 participants, the highest quintile of total olive oil consumption (sum of all categories of olive oil and olive pomace oil) was associated with higher mean values of ABI (beta coefficient: 0.014, 95% confidence interval [CI]: 0.002, 0.027) (p for trend = 0.010). Logistic models comparing the consumption of different categories of olive oils, olive pomace oil and ABI ≤1 values revealed an inverse association between virgin olive oils consumption and the likelihood of a low ABI (odds ratio [OR] 0.73, 95% CI [0.56, 0.97]), while consumption of olive pomace oil was positively associated with a low ABI (OR 1.22 95% CI [1.00, 1.48]). CONCLUSIONS: In a Mediterranean population at high cardiovascular risk, total olive oil consumption was associated with a higher mean ABI. These results suggest that olive oil consumption may be beneficial for peripheral artery disease prevention, but longitudinal studies are needed.


Subject(s)
Cardiovascular Diseases , Ankle , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Cross-Sectional Studies , Heart Disease Risk Factors , Humans , Olive Oil , Plant Oils , Risk Factors
5.
J Environ Manage ; 275: 111253, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32858268

ABSTRACT

In this work, the study of the biomass application of a microphyte plant Slavinia auriculata Aublet in red ceramic was carried out. The waste comes from the phytoremediation process, used in sewage treatment plants. Characterization tests were carried out by chemical, mineralogical, dilatometry, thermal and mass spectrometry techniques, where it was possible to prove that biomass is compatible in its composition for application in ceramic materials and also has great potential to act as a source of energy. The production of specimens was carried out using an industrial clay mass and incorporating 0-10% of biomass in samples produced by pressing and burned at temperatures between 750 and 1050 °C. Properties of plasticity, firing shrinkage, apparent drying and firing density, water absorption, compressive strength and tensile strength in flexion were evaluated, where the feasibility of using up to 2.5% biomass in ceramics firing in 1050 °C s was proven. Although the results of water absorption at the firing temperature of 1050 °C have increased from 18.3% to 19.4% with the use of 2.5% of the residue, the results of tensile strength in flexion have reduced from 4.80 to 3.75 MPa and the results of compressive strength have reduced from 27.6 to 22 MPa, the values obtained meet international recommendations and are in accordance with the recommendations of the bibliography. Finally, an economic analysis of the application of biomass in ceramic materials was carried out, where it was observed that it was possible to save up to 5.04% with the use of the biomass under study, providing an annual savings of $ 2668.8 for the ceramic industry.


Subject(s)
Ceramics , Clay , Biomass , Compressive Strength , Temperature
6.
Int J Biol Macromol ; 98: 654-663, 2017 May.
Article in English | MEDLINE | ID: mdl-28167112

ABSTRACT

Biopolymers as polyhydroxyalkanoates (PHA) composed by different co-monomers 3-hydroxybutyrate and 3-hydroxyhexanoate [P(3HB-co-3HHx)] has attracted interest since its properties are similar to low density polyethylene. Burkholderia sacchari produces this copolymer with a very low 3HHx molar fraction, about 2 mol%. B. sacchari mutant (unable to produce polymer) was engineered to host PHA biosynthesis genes (phaPCJ) from Aeromonas sp. In addition, a two-step bioprocess to increase biopolymer production was developed. The combination of these techniques resulted in the production of P(3HB-co-3HHx) with 3HHx content up to 20 mol%. The PHA content was about 78% of dry biomass, resulting in PHA volumetric productivities around 0.45gl-1h-1. The P(3HB-co-3HHx) containing 20 mol% of 3HHx presented an elongation at brake of 945%, higher than reported before for this PHA composition. Here we have described an approach to increase 3HHx content into the copolymer, allowing the precise control of the 3HHx molar fractions.


Subject(s)
3-Hydroxybutyric Acid/biosynthesis , Biopolymers/biosynthesis , Burkholderia/chemistry , 3-Hydroxybutyric Acid/chemistry , Aeromonas/chemistry , Biopolymers/chemistry , Caproates/chemistry , Fermentation , Polyhydroxyalkanoates/chemistry
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