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1.
Mikrochim Acta ; 191(7): 413, 2024 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904692

RESUMEN

Hepatocellular carcinoma (HCC) is the most common liver malignancy and is characterized by increasing incidence and high mortality rates. Current methods for the screening and diagnosis of HCC exhibit inherent limitations, highlighting the ever-growing need for the development of new methods for the early diagnosis of HCC. The aim of this work was to develop a novel electrochemical aptasensor for the detection of HepG2 cells, a type of circulating tumor cells that can be used as biomarkers for the early detection of HCC. A carbon screen-printed electrode was functionalized with a composite suspension containing graphene oxide, chitosan, and polyaniline nanoparticles to increase the electrode surface and provide anchoring sites for the HepG2 cell-specific aptamer. The aptamer was immobilized on the surface of the functionalized electrode using multipulse amperometry, an innovative technique that significantly reduces the time required for aptamer immobilization. The innovative platform was successfully employed for the first time for the amplification-free detection of HepG2 cells in a linear range from 10 to 200,000 cells/mL, with a limit of detection of 10 cells/mL. The platform demonstrated high selectivity and stability and was successfully used for the detection of HepG2 cells in spiked human serum samples with excellent recoveries.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Carcinoma Hepatocelular , Técnicas Electroquímicas , Grafito , Neoplasias Hepáticas , Humanos , Células Hep G2 , Aptámeros de Nucleótidos/química , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/sangre , Técnicas Electroquímicas/métodos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/sangre , Grafito/química , Técnicas Biosensibles/métodos , Límite de Detección , Compuestos de Anilina/química , Electrodos , Quitosano/química
2.
Animals (Basel) ; 14(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38929396

RESUMEN

The purpose of this study was to analyze the ultrastructure of the testes of sexually immature calves and reproductive bulls of the Polish Holstein-Friesian Black-and-White breed. Utilizing TEM, this study identified three distinct stages of seminiferous tubule development in calves, characterized by varying shapes, distributions, and arrangements of individual cells. In immature animals, early developing spermatocytes, prespermatogonia, and pre-Sertoli cells were observed within the seminiferous tubules. In sexually mature bulls, all cells of the spermatogenic series were observed, situated on a thin, multilayered basal lamina, which forms characteristic undulations. An abundant smooth endoplasmic reticulum was observed in the cytoplasm of spermatogonia in both groups of animals, forming characteristic membranous swirls. In adult bulls, spermatogonia maintain contact with each other through numerous cytoplasmic bridges and cell connections, forming small spaces with visible microvilli between them. The ultrastructural analysis facilitated the identification of morphological changes occurring during the maturation of pre-Sertoli cells, transitioning from a large euchromatic nucleus to a nucleus in which the formation of characteristic vesicles and tubules could be observed. It should also be emphasized that two types of Sertoli cells, namely dark and light electron-dense cells, can be found in cattle. These cells differ from each other, indicating that they may perform different functions. The widespread recognition of the presence of two types of Sertoli cells in cattle will undoubtedly contribute to a better understanding of the processes occurring within the testes and provide a basis for further research in this area.

3.
Pharmacy (Basel) ; 12(2)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38668094

RESUMEN

In Tunisia, self-medication is a common practice, and there is a continual rise in the prevalence of cardiovascular disease. Given the lack of data on the self-medication practices (SMPs) among cardiovascular patients in this area, the present study aimed to identify the prevalence and determinants of SMPs among cardiovascular patients in the city of Béja. A community-pharmacy-based survey was conducted among selected cardiovascular patients in Béja, Tunisia, from May 2021 to June 2021. Data were collected using a self-administered questionnaire provided by pharmacists during in-person surveys with patients. Descriptive statistics were used to summarize the data, while Fisher's exact test was used for categorical variables, with the significance level set at p < 0.05. The frequency of self-medication among the 150 respondents was 96%; 70.14% of participants reported that the primary reason why people engage in self-medication is the existence of an old prescription. The most prevalent conditions leading patients to self-medicate were headaches (100%), fever (83.33%), toothache (65.97%), and dry cough (47.92%). The most frequently self-administered drugs were paracetamol (100%), antibiotics (56.94%), and antitussives (47.92%). The results of our study indicate that SMPs among Tunisian cardiovascular patients have a high prevalence. With this in mind, healthcare practitioners should ask their patients about their self-medication practices and advise cardiovascular patients about the risks and benefits associated with this practice.

4.
Drug Dev Ind Pharm ; 50(5): 446-459, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38622817

RESUMEN

OBJECTIVE: The aim of the present study was to develop and optimize a wound dressing film loaded with chloramphenicol (CAM) and ibuprofen (IBU) using a Quality by Design (QbD) approach. SIGNIFICANCE: The two drugs have been combined in the same dressing as they address two critical aspects of the wound healing process, namely prevention of bacterial infection and reduction of inflammation and pain related to injury. METHODS: Three critical formulation variables were identified, namely the ratios of Kollicoat SR 30D, polyethylene glycol 400 and polyvinyl alcohol. These variables were further considered as factors of an experimental design, and 17 formulations loaded with CAM and IBU were prepared via solvent casting. The films were characterized in terms of dimensions, mechanical properties and bioadhesion. Additionally, the optimal formulation was characterized regarding tensile properties, swelling behavior, water vapor transmission rate, surface morphology, thermal behavior, goniometry, in vitro drug release, cell viability, and antibacterial activity. RESULTS: The film was optimized by setting minimal values for the folding endurance, adhesive force and hardness. The optimally formulated film showed good fluid handling properties in terms of swelling behavior and water vapor transmission rate. IBU and CAM were released from the film up to 80.9% and 82.5% for 8 h. The film was nontoxic, and the antibacterial activity was prominent against Micrococcus spp. and Streptococcus pyogenes. CONCLUSIONS: The QbD approach was successfully implemented to develop and optimize a novel film dressing promising for the treatment of low-exuding acute wounds prone to infection and inflammation.


Asunto(s)
Antibacterianos , Vendajes , Cloranfenicol , Ibuprofeno , Cicatrización de Heridas , Ibuprofeno/administración & dosificación , Ibuprofeno/química , Ibuprofeno/farmacología , Cicatrización de Heridas/efectos de los fármacos , Cloranfenicol/administración & dosificación , Cloranfenicol/farmacología , Cloranfenicol/química , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/química , Liberación de Fármacos , Humanos , Alcohol Polivinílico/química , Polietilenglicoles/química , Animales , Supervivencia Celular/efectos de los fármacos , Química Farmacéutica/métodos
5.
Pharmaceuticals (Basel) ; 16(6)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37375800

RESUMEN

Pharmacological responses vary by sex in several illnesses. This narrative review summarizes sex variations in pharmaceutical response in SARS-CoV-2 infection, dyslipidemia, and diabetes mellitus. Infection with SARS-CoV-2 is more severe and deadly in men than women. This may be attributed to immunological responses, genetics, and hormones. Some research shows that men may respond better to genomic vaccinations and females to antiviral medications such as remdesivir (Moderna and Pfizer-BioNTech). In dyslipidemia, women tend to have greater HDL-C and lower LDL-C than men. Some studies show that females may need lower statin dosages than men to obtain equal LDL-C reductions. Ezetimibe co-administered with a statin significantly improved lipid profile indicators in men compared to women. Statins reduce dementia risk. Atorvastatin decreased dementia risk in males (adjusted HR 0.92, 95% CI 0.88-0.97), whereas lovastatin lowered dementia risk in women (HR 0.74, 95% CI 0.58-0.95). In diabetes mellitus, evidence suggests that females may have a higher risk of developing certain complications such as diabetic retinopathy and neuropathy, despite having lower rates of cardiovascular disease than males. This could be the result of differences in hormonal influences and genetic factors. Some research shows females may respond better to oral hypoglycemic medications such as metformin. In conclusion, sex-related differences in pharmacological response have been observed in SARS-CoV-2 infection, dyslipidemia, and diabetes mellitus. Further research is needed to better understand these differences and to develop personalized treatment strategies for males and females with these conditions.

6.
Ther Deliv ; 14(2): 157-173, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-37158273

RESUMEN

Silica nanoparticles (SiO2) are increasingly investigated for biomedical applications. Aim: This study aimed to analyze the potential use of a SiO2 nanoparticles coated with biocompatible polydopamine (SiO2@PDA) as a potential chemotherapeutic drug carrier. Materials & methods: SiO2 morphology and PDA adhesion was analyzed by dynamic light scattering, electron microscopy and nuclear magnetic resonance. Cytotoxicity studies and morphology analyses (immunofluorescence, scanning and transmission electron microscopy) were used to assess the cellular reaction to the SiO2@PDA nanoparticles and to identify a biocompatible (safe use) window. Results & conclusion: Concentrations above 10 µg/ml and up to 100 µg/ml SiO2@PDA showed the best biocompatibility on human melanoma cells at 24 h and represent a potential drug carrier template for targeted melanoma cancer treatment.


Tiny particles can be small enough to enter cells. This is why they may be useful in the treatment of cancer. We made particles in a way that is friendly for human cells, then we analyzed their effects on cancer cells. Our tests showed that these particles could be useful for treatment because they do not worsen cancer cells. This is important because sometimes after treatment, cancer cells can become more dangerous. This way, even if the drug did not work, the cancer will not worsen.


Asunto(s)
Melanoma , Nanopartículas , Humanos , Portadores de Fármacos , Dióxido de Silicio , Melanoma/tratamiento farmacológico
7.
ACS Omega ; 8(17): 14952-14964, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37151495

RESUMEN

In this study, three different morphologies, nanoflower (NF), nano sponge (NS), and nano urchin (NU), of zinc oxide (ZnO) nanostructures were synthesized successfully via a mild hydrothermal method. After synthesis, the samples were annealed in the atmosphere at 300, 600, and 800 °C. Although annealing provides different degradation kinetics for different morphologies, ZnO NS performed significantly better than other morphologies for all annealing temperatures we used in the study. When the photoluminescence, electron paramagnetic resonance spectroscopy, BET surface, and X-ray diffraction analysis results are examined, it is revealed that the defect structure, pore diameter, and crystallinity cumulatively affect the photocatalytic activity of ZnO nanocatalysts. As a result, to obtain high photocatalytic activity in rhodamine B (RhB) degradation, it is necessary to develop a ZnO catalyst with fewer core defects, more oxygen vacancies, near band emission, large crystallite size, and large pore diameter. The ZnO NS-800 °C nanocatalyst studied here had a 35.6 × 10-3 min-1 rate constant and excellent stability after a 5-cycle photocatalytic degradation of RhB.

8.
Microorganisms ; 11(3)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36985318

RESUMEN

Bacterial infections are a major concern as antibiotic resistance poses a great threat, therefore leading to a race against time into finding new drugs or improving the existing resources. Nanomaterials with high surface area and bactericidal properties are the most promising ones that help combating microbial infections. In our case, graphene decorated with silver nanoparticles Gr-Ag (5 wt% Ag) exhibited inhibitory capacity against S. aureus and E. coli. The newly formed hybrid material was next incubated with high-efficiency particulate air (HEPA) filter, to obtain one with bactericidal properties. The modified filter had greater inhibitory action against the tested strains, compared to the control, and the effect was better against the Gram-negative model. Even if the bacteria remained attached to the filters, their colony forming unit capacity was affected by the Gr-Ag (5 wt% Ag) hybrid material, when they were subsequently re-cultured on fresh agar media. Therefore, the HEPA filter modified with Gr-Ag (5 wt% Ag) has high antibacterial properties that may substantially improve the existing technology.

9.
Pharmaceutics ; 15(3)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36986870

RESUMEN

A biogenic carrier for 5-fluorouracil (5-FU) loading and subsequent tableting as a new drug formulation for slow release has been proposed using the biomineral from blue crab carapace. Due to its highly ordered 3D porous nanoarchitecture, the biogenic carbonate carrier could achieve increased effectiveness in colorectal cancer cure provided that the formulation would successfully pass through the gastric acid conditions. Following the recently proven viability of the concept by demonstrating the slow release of the drug from the carrier using the highly sensitive SERS technique, here we investigated the 5-FU release from the composite tablet drug in pH conditions replicating the gastric environment. The released drug from the tablet was studied in solutions with three relevant pH values, pH 2, pH 3, and pH 4. The 5-FU SERS spectral signature for each pH value was used to build calibration curves for quantitative SERS analysis. The results suggested a similarly slow-releasing pattern in acid pH environments to that in neutral conditions. Although biogenic calcite dissolution was expected in acid conditions, the X-ray diffraction and Raman spectroscopy showed preservation of calcite mineral along with the monohydrocalcite during acid solution exposure for two hours. The total released amount in a time course of seven hours, however, was lower in acidic pH solutions, with a maximum fraction of ~40% of the total amount of loaded drug, for pH 2, as opposed to ~80% for neutral values. Nonetheless, these results clearly prove that the novel composite drug retains its slow-releasing character in environmental conditions compatible with the gastrointestinal pH and that it is a viable and biocompatible alternative for oral delivery of anticancer drug to reach the lower gastro-intestinal tract.

10.
Int J Pharm ; 635: 122700, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36764419

RESUMEN

Diabetic retinopathy (DR) is one of the most serious complications of diabetes, which leads to blindness. By addressing the traditional treatment limitations, we developed a novel light-responsive targeted polymeric microcapsule able to encapsulate a near infrared (NIR) photoactive fluorophore - Indocyanine Green, owing to its photothermal properties. Moreover, for an efficient in vitro targeted drug delivery, the fluorescent microsystem was conjugated with a therapeutic agent, i.e., Avastin drug - a Food and Drug Administration approved therapeutic antibody. The microcapsules were fabricated and evaluated in terms of morphology, encapsulation and drug conjugation efficiency and its release capacity. Avastin-conjugated microcapsules with an average dimension of 4.5 ± 0.35 µm were obtained, according to Scanning Electron Microscopy and Re-Scanning Confocal Microscopy (RCM) investigations. The capacity of the microcapsules to operate as effective phototherapeutic agents by generating heat under NIR laser irradiation was evaluated, followed by the investigation of the microcapsule's shell rupture and NIR laser-induced release of Avastin. The biocompatibility of the Avastin-conjugated microcapsules was proven by WST-1 assay. In vitro cellular internalization and localization of the Avastin microcarriers were determined through Conventional fluorescence microscopy, RCM and Transmission Electron Microscopy imaging techniques. Finally, the Avastin-conjugated microcapsules were validated for in vitro targeted drug delivery and release directly under simulated DR conditions, which could certainly become a successful strategy in DR fighting.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Cápsulas , Bevacizumab , Retinopatía Diabética/tratamiento farmacológico , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Diabetes Mellitus/tratamiento farmacológico
11.
Medicina (Kaunas) ; 59(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36676728

RESUMEN

Three ceramic and composite computer-aided design/computer-aided manufacturing (CAD/CAM) materials from different manufacturers (Cerasmart (CS)-nanoceramic resin; Straumann Nice (SN)-glass ceramic and Tetric CAD (TC)-composite resin) were tested to investigate the biocompatibility and sustainability on human fibroblasts and keratinocytes cells. Each type of CAD/CAM blocks restorative materials with fine and rough surfaces was exposed to an acidic environment for one month. After that, various powders were obtained by milling. In parallel, powders were also prepared from each restorative material, which were not exposed to the acidic environment. The cytotoxic effects were investigated by means of MTT and LDH assays, as well as nitric oxide production on two human normal cell lines, namely, fibroblasts (BJ) and keratinocytes (HaCaT). In addition, the degree of adhesion of fibroblast cells to each CAD/CAM material was evaluated by scanning electron microscopy (SEM). The results showed that the two samples that were exposed to an acidic environment (CS and SN) induced a reduction of mitochondrial activity and plasma membrane damage as regards the fibroblast cells. A similar effect was observed in TC_fine-exposed material, which seemed to induce necrosis at the tested concentration of 1 mg/mL. No oxidative stress was observed in fibroblasts and keratinocytes treated with the CAD/CAM materials. Regarding the adhesion degree, it was found that the fibroblasts adhere to all the occlusal veneers tested, with the mention that the CS and SN materials have a weaker adhesion with fewer cytoplasmic extensions than TC material. With all of this considered, the CAD/CAM restorative materials tested are biocompatible and represent support for the attachment and dispersion of cells.


Asunto(s)
Diseño Asistido por Computadora , Humanos , Ensayo de Materiales , Propiedades de Superficie , Microscopía Electrónica de Rastreo
12.
Colloids Surf B Biointerfaces ; 220: 112915, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36257280

RESUMEN

Diabetic retinopathy (DR) is a severe ocular complication that causes retinal damage, being one of the leading causes of blindness globally, thus the development of new strategies to prevent and treat DR as well as other degenerative diseases is highly desired. This work is focused on the design and fabrication of an ingenious model of polymeric microcapsules (MC) for controlled drug delivery in human retina cells able to carry therapeutic resveratrol (RSV) molecules in tandem with active anisotropic gold bipyramidal nanoparticles (AuBPs) as efficient photothermal agents. Specifically, MC were developed via a Layer-by-Layer deposition technique, by successively adding oppositely charged polyelectrolytes on a RSV-conjugated calcium carbonate (CaCO3) core. For the monitorization and localization of the as-formed spherical fluorescent MC inside human retina pigmented epithelial (RPE) D407 cells, fluorescein isothiocyanate, a Food and Drug Administration approved fluorophore, was attached between the polyelectrolytes layers. High-performance liquid chromatography analysis revealed a loading efficiency of over 90% of RSV on the CaCO3 core and demonstrates its release upon NIR irradiation as a consequence of the thermoplasmonic effect of MC. The cytotoxicity of the RSV-carrying MC inside human retina cells was assessed by WST-1 assay. Finally, cellular internalization and localization of the MC inside living RPE cells were monitored via Conventional Fluorescence and Re-Scanning Confocal Fluorescence Microscopy. This research seeks to take use of the novel MC and implement them as potential intraocular RSV delivery vehicles for the therapy of DR.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanopartículas , Humanos , Resveratrol/farmacología , Polielectrolitos , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Polímeros , Cápsulas/química
13.
Gels ; 8(8)2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36005084

RESUMEN

Dexamethasone is one of the most often used corticosteroid drugs for sensorineural hearing loss treatment, and is used either by intratympanic injection or through systemic delivery. In this study, a biopolymer lipid hybrid microcarrier was investigated for enhanced local drug delivery and sustained release at the round window membrane level of the middle ear for the treatment of sensorineural hearing loss (SNHL). Dexamethasone-loaded and dexamethasone-free microparticles were prepared using biopolymers (polysaccharide and protein, pectin and bovine serum albumin, respectively) combined with lipid components (phosphatidylcholine and Dimethyldioctadecylammonium bromide) in order to obtain a biopolymer-liposome hybrid system, with a complex structure combining to enhance performance in terms of physical and chemical stability. The structure of the microparticles was evaluated by FTIR, XRD, thermal analysis, optical microscopy, and scanning electron microscopy (SEM). The encapsulation efficiency determination and the in vitro Dexamethasone release study were performed using UV-Vis spectroscopy. The high value of encapsulation efficiency and the results of the release study indicated six days of sustained release, encouraging us to evaluate the in vitro cytotoxicity of Dexamethasone-loaded microparticles and their influence on the cytotoxicity induced by Cisplatin on auditory HEI-OC1 cells. The results show that the new particles are able to protect the inner ear sensory cells.

15.
Sci Rep ; 12(1): 9584, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-35688863

RESUMEN

Differences in crystallinity, structure and composition variation along the growing direction in gilthead seabream, Sparus aurata otoliths that inhabited different environments were determined to evaluate the correlation of spectroscopic and chemical data with the lifetime development and movement pattern. The Raman spectroscopy signal provided the characteristic bands whose Full Width at Half Maximum (FWHM) were used to track the signal variability. The FWHM showed an initial increase in the core area, followed by a decrease depicting two minima coinciding growth rings. The crystal discontinuity linked to annual rings was confirmed. The FWHM pattern followed cycle in the individual's activity. However, no significant correlation with FWHM and environmental factors although the slope of the FWHM variation distinguished aquaculture and costal groups from open sea and transitional, estuarine waters. Raman data were further correlated with morphological and elemental composition obtained via SEM-EDX and by LA-ICP-MS. SEM clearly confirmed CRM findings. Finally, multiparameter analysis of Ba/Ca concentrations obtained by LA-ICP-MS indicated the separation of groups associated with aquaculture and transitional waters due lowest variability in the elemental composition. Other groups are more variable possibly due to the water oligotrophic character and greater variability in prey availability in each environment. Results of the present study showed the additional potential of Raman spectroscopy as a complementary tool for inference of migration or origin of fish based on otolith composition and structure like other well-established technique.


Asunto(s)
Dorada , Animales , Acuicultura , Membrana Otolítica
16.
J Pers Med ; 12(6)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35743692

RESUMEN

In the last decades, both animal and human studies have neglected female subjects with the aim of evading a theorized intricacy of feminine hormonal status. However, clinical experience proves that pharmacological response may vary between the two sexes since pathophysiological dissimilarities between men and women significantly influence the pharmacokinetics and pharmacodynamics of drugs. Sex-related differences in central nervous system (CNS) medication are particularly challenging to assess due to the complexity of disease manifestation, drugs' intricate mechanisms of action, and lack of trustworthy means of evaluating the clinical response to medication. Although many studies showed contrary results, it appears to be a general tendency towards a certain sex-related difference in each pharmacological class. Broadly, opioids seem to produce better analgesia in women especially when they are administered for a prolonged period of time. On the other hand, respiratory and gastrointestinal adverse drug reactions (ADRs) following morphine therapy are more prevalent among female patients. Regarding antidepressants, studies suggest that males might respond better to tricyclic antidepressants (TCAs), whereas females prefer selective serotonin reuptake inhibitors (SSRI), probably due to their tolerance to particular ADRs. In general, studies missed spotting any significant sex-related differences in the therapeutic effect of antiepileptic drugs (AED), but ADRs have sex variations in conjunction with sex hormones' metabolism. On the subject of antipsychotic therapy, women appear to have a superior response to this pharmacological class, although there are also studies claiming the opposite. However, it seems that reported sex-related differences regarding ADRs are steadier: women are more at risk of developing various side effects, such as metabolic dysfunctions, cardiovascular disorders, and hyperprolactinemia. Taking all of the above into account, it seems that response to CNS drugs might be occasionally influenced by sex as a biological variable. Nonetheless, although for each pharmacological class, studies generally converge to a certain pattern, opposite outcomes are standing in the way of a clear consensus. Hence, the fact that so many studies are yielding conflicting results emphasizes once again the need to address sex-related differences in pharmacological response to drugs.

17.
Materials (Basel) ; 15(9)2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35591388

RESUMEN

This study presents the correct processing of Co-Cr alloys as a method of preserving the properties of the materials as-cast, and therefore they can be safely placed in contact with the oral cavity tissues as resistance frameworks. The basic materials analyzed in this study were five commercial Co-Cr dental alloys with different components obtained in three processing steps. The analysis of the electrochemical behavior at the surface of the Co-Cr alloys was performed by electrochemical measurements: impedance spectroscopy (EIS), open circuit electrical potential (OCP), and linear polarization (LP). In terms of validation, all five alloys had a tendency to generate a stable oxide layer at the surface. After the measurements and the graphical representation, the alloy that had a higher percentage of tungsten (W) and iron (Fe) in composition showed a higher tendency of anodizing. After the application of the heat treatment, the disappearance of the hexagonal phase was observed, with the appearance of new phases of type (A,B)2O3 corresponding to some oxide compounds, such as Fe2O3, Cr2O3, (Cr,Fe)2O3, and CoMnO3. In conclusion, the processing of Co-Cr alloys by melting and casting in refractory molds remains a viable method that can support innovation, in the context of technology advance in recent years towards digitalization of the manufacturing process, i.e., the construction of prosthetic frameworks conducted by additive methods using Co-Cr powder alloy.

18.
Colloids Surf B Biointerfaces ; 216: 112536, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35567806

RESUMEN

Engineered nanomaterials are increasingly used in everyday life applications and, in consequence, significant amounts are being released into the environment. From soil, water, and air they can reach the organelles of edible plants, potentially impacting the food chain and human health. The potential environmental and health impact of these nanoscale materials is of public concern. TiO2 and ZnO are among the most significant nanomaterials in terms of production amounts. Our study aimed at evaluating the effects of large-scale TiO2 (~100 nm) and ZnO (~200 nm) nanoparticles on soybean plants grown in vitro. The effect of different concentrations of nanoparticles (10, 100, 1000 mg/L) was evaluated regarding plant morphology and metabolic changes. ZnO nanoparticles showed higher toxicity compared to TiO2 in the experimental set-up. Overall, elevated levels of chlorophylls and proteins were observed, as well as increased concentrations of ascorbic and dehydroascorbic acids. Also, the decreasing stomatal conductance to water vapor and net CO2 assimilation rate show higher plant stress levels. In addition, ZnO nanoparticle treatments severely affected plant growth, while TEM analysis revealed ultrastructural changes in chloroplasts and rupture of leaf cell walls. By combining ICP-OES and TEM results, we were able to show that the nanoparticles were metabolized, and their internalization in the soybean plant tissues occurred in ionic forms. This behavior most likely is the main driving force of nanoparticle toxicity.


Asunto(s)
Nanopartículas , Óxido de Zinc , Humanos , Nanopartículas/metabolismo , Glycine max , Titanio/toxicidad , Óxido de Zinc/química
19.
J Clin Med ; 11(7)2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35407628

RESUMEN

Since the prevalence of heart failure (HF) increases with age, HF is now one of the most common reasons for the hospitalization of elderly people. Although the treatment strategies and overall outcomes of HF patients have improved over time, hospitalization and mortality rates remain elevated, especially in developed countries where populations are aging. Therefore, this paper is intended to be a valuable multidisciplinary source of information for both doctors (cardiologists and general physicians) and pharmacists in order to decrease the morbidity and mortality of heart failure patients. We address several aspects regarding pharmacological treatment (including new approaches in HF treatment strategies [sacubitril/valsartan combination and sodium glucose co-transporter-2 inhibitors]), as well as the particularities of patients (age-induced changes and sex differences) and treatment (pharmacokinetic and pharmacodynamic changes in drugs; cardiorenal syndrome). The article also highlights several drugs and food supplements that may worsen the prognosis of HF patients and discusses some potential drug-drug interactions, their consequences and recommendations for health care providers, as well as the risks of adverse drug reactions and treatment discontinuation, as an interdisciplinary approach to treatment is essential for HF patients.

20.
ACS Omega ; 6(42): 27773-27780, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34722977

RESUMEN

Due to their chemical composition, richness in calcium carbonate, chitin, proteins, and pigments, and nanoporous structure, crustacean shell waste shows great potential for a wide variety of applications. Large quantities of waste shells are produced annually, meaning that they can be considered a renewable source of ecofriendly biogenic materials, which can be turned into value-added byproducts. In this paper, an IR-based technique is developed to differentiate various biogenic powders originated from crude or food-processed crustacean shells. The validity of the method is supported by cross-checking with XRD, NMR, and SEM-EDX analyses. Our goal was to determine changes in properties of waste crab shells after the two most common treatments, deproteinization and milling. We discovered that deproteinization with NaOH could be tracked from the IR absorbance intensity ratio of the υ(CH2,3) and υasym(CO3 2-) bands while milling time less influenced this ratio but induced changes in powder particle size distribution and morphology. The relative organic/inorganic ratio was different for different colored shells. Unexpectedly, waste shells stored for an average of 6 months or more were found to contain hydrated calcium carbonate (monohydrocalcite), which was absent in equivalent fresh shell composition. Deproteinization caused changes in mechanical properties of shells, making them more brittle, which resulted in a larger fraction of fine particles after powdering.

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