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1.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37834039

RESUMEN

The polysaccharide FucoPol has recently been shown to yield hydrogel membranes (HMs) characterized by good mechanical properties, biocompatibility, and anti-inflammatory activity that render them promising biomaterials for use in the biomedical field. Subsequently to such findings, envisaging their development into novel delivery systems for topical applications, in this study, FucoPol HMs prepared by crosslinking the biopolymer with iron cations were loaded with caffeine or diclofenac sodium as model drugs. Two loading methods, namely diffusion and mixing, were applied to evaluate the FucoPol's HM drug-loading capacity and entrapment efficiency. The diffusion method led to a higher caffeine loading (101.9 ± 19.1 mg/g) in the HM1_DCAF membranes, while the mixing method resulted in a higher diclofenac sodium loading (82.3 ± 5.1 mg/g) in the HM1_DDS membranes. The HM1_DCAF membranes were characterized by increased mechanical and rheological parameters, such as their hardness (130.0 ± 5.3 kPa) and storage modulus (1014.9 ± 109.7 Pa), compared to the HM1_DDS membranes that exhibited lower values (7.3 ± 1.2 kPa and 19.8 ± 3.8 Pa, respectively), probably due to leaching occurring during the drug-loading process. The release profiles revealed a fast release of both APIs from the membranes loaded by diffusion, while a prolonged and sustained release was obtained from the membranes loaded by mixing. Moreover, for all API-loaded membranes, the release mechanism followed Fickian diffusion, with the release rate being essentially governed by the diffusion process. These findings, together with their previously shown biological properties, support the suitability of the developed FucoPol HMs to be used as platforms for the topical delivery of drugs.


Asunto(s)
Diclofenaco , Hidrogeles , Cafeína , Portadores de Fármacos , Antiinflamatorios
2.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37513903

RESUMEN

FucoPol, a fucose-rich polyanionic polysaccharide, was used for the first time for the preparation of hydrogel membranes (HMs) using Fe3+ as a crosslinking agent. This study evaluated the impact of Fe3+ and FucoPol concentrations on the HMs' strength. The results show that, above 1.5 g/L, Fe3+ concentration had a limited influence on the HMs' strength, and varying the FucoPol concentration had a more significant effect. Three different FucoPol concentrations (1.0, 1.75 and 2.5 wt.%) were combined with Fe3+ (1.5 g/L), resulting in HMs with a water content above 97 wt.% and an Fe3+ content up to 0.16 wt.%. HMs with lower FucoPol content exhibited a denser porous microstructure as the polymer concentration increased. Moreover, the low polymer content HM presented the highest swelling ratio (22.3 ± 1.8 g/g) and a lower hardness value (32.4 ± 5.8 kPa). However, improved mechanical properties (221.9 ± 10.2 kPa) along with a decrease in the swelling ratio (11.9 ± 1.6 g/g) were obtained for HMs with a higher polymer content. Furthermore, all HMs were non-cytotoxic and revealed anti-inflammatory activity. The incorporation of FucoPol as a structuring agent and bioactive ingredient in the development of HMs opens up new possibilities for its use in tissue engineering, drug delivery and wound care management.

3.
Biomedicines ; 11(3)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36979779

RESUMEN

Gastric cancer (GC) ranked as the fifth most incident cancer in 2020 and the third leading cause of cancer mortality. Surgical prevention and radio/chemotherapy are the main approaches used in GC treatment, and there is an urgent need to explore and discover innovative and effective drugs to better treat this disease. A new strategy arises with the use of repurposed drugs. Drug repurposing coupled with drug combination schemes has been gaining interest in the scientific community. The main objective of this project was to evaluate the therapeutic effects of alternative drugs in GC. For that, three GC cell lines (AGS, MKN28, and MKN45) were used and characterized. Cell viability assays were performed with the reference drug 5-fluororacil (5-FU) and three repurposed drugs: natamycin, nitazoxanide, and benztropine. Nitazoxanide displayed the best results, being active in all GC cells. Further, 5-FU and nitazoxanide in combination were tested in MKN28 GC cells, and the results obtained showed that nitazoxanide alone was the most promising drug for GC therapy. This work demonstrated that the repurposing of drugs as single agents has the ability to decrease GC cell viability in a concentration-dependent manner.

4.
Polymers (Basel) ; 15(4)2023 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-36850075

RESUMEN

Chitin-glucan complex (CGC) hydrogels were fabricated by coagulation of the biopolymer from an aqueous alkaline solution, and their morphology, swelling behavior, mechanical, rheological, and biological properties were studied. In addition, their in vitro drug loading/release ability and permeation through mimic-skin artificial membranes (Strat-M) were assessed. The CGC hydrogels prepared from 4 and 6 wt% CGC suspensions (Na51*4 and Na51*6 hydrogels, respectively) had polymer contents of 2.40 ± 0.15 and 3.09 ± 0.22 wt%, respectively, and displayed a highly porous microstructure, characterized by compressive moduli of 39.36 and 47.30 kPa and storage moduli of 523.20 and 7012.25 Pa, respectively. Both hydrogels had a spontaneous and almost immediate swelling in aqueous media, and a high-water retention capacity (>80%), after 30 min incubation at 37 °C. Nevertheless, the Na51*4 hydrogels had higher fatigue resistance and slightly higher-water retention capacity. These hydrogels were loaded with caffeine, ibuprofen, diclofenac, or salicylic acid, reaching entrapment efficiency values ranging between 13.11 ± 0.49% for caffeine, and 15.15 ± 1.54% for salicylic acid. Similar release profiles in PBS were observed for all tested APIs, comprising an initial fast release followed by a steady slower release. In vitro permeation experiments through Strat-M membranes using Franz diffusion cells showed considerably higher permeation fluxes for caffeine (33.09 µg/cm2/h) and salicylic acid (19.53 µg/cm2/h), compared to ibuprofen sodium and diclofenac sodium (4.26 and 0.44 µg/cm2/h, respectively). Analysis in normal human dermal fibroblasts revealed that CGC hydrogels have no major effects on the viability, migration ability, and morphology of the cells. Given their demonstrated features, CGC hydrogels are very promising structures, displaying tunable physical properties, which support their future development into novel transdermal drug delivery platforms.

5.
Rev. chil. nutr ; 50(1)feb. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1431738

RESUMEN

Hemodialysis, along with chronic kidney disease (CKD), intensifies the inflammatory process and oxidative stress in patients undergoing treatment. In this context, Vitamin E supplementation can mitigate the deleterious effects resulting from these processes. This is a systematic review whose objective was to evaluate the effect of Vitamin E supplementation on inflammatory biomarkers and oxidative stress in patients with CKD on hemodialysis. This review was prepared according to the methodology for systematic reviews and meta-analyses (PRISMA) and the search was performed in Pubmed, Cochrane Library, Scopus and Web of Science databases. The risk of bias of the included studies was assessed with the Cochrane Risk of Bias Tool. Twelve studies developed between 2006 and 2020 were included in this review. Most of them (n= 11) used vitamin E doses ranging from 400 IU to 888 IU and the supplementation time ranged from 2 weeks to 12 months. Of all the 12 articles included, 25% (n= 3) analyzed supplementation on biomarkers of oxidative stress and 25% (n= 3) addressed these parameters simultaneously. A positive effect was observed in 58.4% of the studies (n= 7). Thus, Vitamin E supplementation can be effective in mitigating the inflammatory process and oxidative stress, however, it is worth noting that the effect depends on the dose and time of supplementation.


La hemodiálisis, junto con la enfermedad renal crónica (ERC), intensifica el proceso inflamatorio y el estrés oxidativo en los pacientes en tratamiento. En este contexto, la suplementación con vitamina E puede mitigar los efectos nocivos resultantes de estos procesos. Esta es una revisión sistemática cuyo objetivo fue evaluar el efecto de la suplementación con vitamina E sobre biomarcadores inflamatorios y estrés oxidativo en pacientes con ERC en hemodiálisis. La revisión se elaboró según la metodología para revisiones sistemáticas y metanálisis (PRISMA) y la búsqueda se realizó en las bases de datos Pubmed, Cochrane Library, Scopus y Web of Science. El riesgo de sesgo de los estudios incluidos se evaluó con la Herramienta Cochrane de Riesgo de Sesgo (Cochrane Risk of Bias Tool). En esta revisión se incluyeron doce estudios desarrollados entre 2006 y 2020. La mayoría (n= 11) utilizó dosis de vitamina E que oscilaban entre 400 UI y 888 UI y el tiempo de suplementación osciló entre 2 semanas y 12 meses. De los 12 artículos incluidos, 25% (n= 3) analizaba la suplementación en biomarcadores inflamatorios, 50% (n= 6) en biomarcadores de estrés oxidativo y 25% (n= 3) en estos parámetros simultáneamente. Se observó un efecto positivo en 58,4% de los estudios (n= 7). Por lo tanto, la suplementación con vitamina E puede ser efectiva para mitigar el proceso inflamatorio y el estrés oxidativo, sin embargo, vale la pena señalar que el efecto depende de la dosis y el tiempo de suplementación.

6.
Molecules ; 27(21)2022 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-36363992

RESUMEN

FucoPol is an acylated polysaccharide with demonstrated valuable functional properties that include a shear thinning fluid behaviour, a film-forming capacity, and an emulsion forming and stabilizing capacity. In this study, the different conditions (concentration, temperature, and time) for alkaline treatment were investigated to deacylate FucoPol. Complete deacetylation and desuccinylation was achieved with 0.02 M NaOH, at 60 °C for 15 min, with no significant impact on the biopolymer's sugar composition, pyruvate content, and molecular mass distribution. FucoPol depyruvylation by acid hydrolysis was attempted, but it resulted in a very low polymer recovery. The effect of the ionic strength, pH, and temperature on the deacetylated/desuccinylated polysaccharide, d-FucoPol, was evaluated, as well as its emulsion and film-forming capacity. d-FucoPol aqueous solutions maintained the shear thinning behaviour characteristic of FucoPol, but the apparent viscosity decreased significantly. Moreover, contrary to FucoPol, whose solutions were not affected by the media's ionic strength, the d-FucoPol solutions had a significantly higher apparent viscosity for a higher ionic strength. On the other hand, the d-FucoPol solutions were not affected by the pH in the range of 3.6-11.5, while FucoPol had a decreased viscosity for acidic pH values and for a pH above 10.5. Although d-FucoPol displayed an emulsification activity for olive oil similar to that of FucoPol (98 ± 0%) for an oil-to-water ratio of 2:3, the emulsions were less viscous. The d-FucoPol films were flexible, with a higher Young's modulus (798 ± 152 MPa), a stress at the break (22.5 ± 2.5 MPa), and an elongation at the break (9.3 ± 0.7%) than FucoPol (458 ± 32 MPa, 15.5 ± 0.3 MPa and 8.1 ± 1.0%, respectively). Given these findings, d-FucoPol arises as a promising novel biopolymer, with distinctive properties that may render it useful for utilization as a suspending or emulsifier agent, and as a barrier in coatings and packaging films.


Asunto(s)
Fucosa , Polisacáridos , Emulsiones , Polisacáridos/química , Viscosidad , Biopolímeros , Reología
7.
Horm Metab Res ; 54(12): 785-794, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35952684

RESUMEN

Adipose tissue is a metabolically dynamic organ that is the primary site of storage for excess energy, but it serves as an endocrine organ capable of synthesizing a number of biologically active compounds that regulate metabolic homeostasis. However, when the capacity of expansion of this tissue exceeds, dysfunction occurs, favoring ectopic accumulation of fat in the visceral, which has been implicated in several disease states, most notably obesity. This review highlights the mechanisms involved in the structure of adipose tissue, tissue expandability, adipocyte dysfunction, as well as the impact of these events on the manifestation of important metabolic disorders associated with adipose tissue dysfunction. A literature search using Pubmed, Web of Science, Scopus, and Cochrane databases were used to identify relevant studies, using clinical trials, experimental studies in animals and humans, case-control studies, case series, letters to the editor, and review articles published in English, without restrictions on year of publication. The excessive ectopic lipid accumulation leads to local inflammation and insulin resistance. Indeed, overnutrition triggers uncontrolled inflammatory responses white adipose tissue, leading to chronic low-grade inflammation, therefore fostering the progression of important metabolic disorders. Thus, it is essential to advance the understanding of the molecular mechanisms involved in adipose tissue dysfunction in order to mitigate the negative metabolic consequences of obesity.


Asunto(s)
Tejido Adiposo , Enfermedades Metabólicas , Humanos , Enfermedades Metabólicas/etiología , Obesidad
8.
Vet Sci ; 9(8)2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35893776

RESUMEN

Human gastric cancer (GC) ranks as the fifth most prevalent cancer worldwide, and is the third leading cause of cancer-related death. The incidence of GC is lower in dogs than in humans, accounting for less than 1% of all canine malignancies. In recent years, efforts have been made to understand the pathogenesis of GC and in find an appropriate therapy to maximize curative results, such as adjuvant chemotherapy treatments in addition to surgery. Although surgery is the first-line treatment, it is associated with several complications. In terms of chemotherapeutic intervention, canine gastric cancer has not received much attention, probably due to its late diagnosis, fast progression, low median survival time, and very high mortality rate, along with the lack of publications with concrete scientific results. In this review, we explore canine GC and the pharmacological approach used in the treatment of this often-fatal disease.

9.
Clin Nutr ; 41(4): 862-884, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35276570

RESUMEN

BACKGROUND & AIMS: Selenium is an antioxidant and anti-inflammatory nutrient and regulates important physiological processes, such as carbohydrate and lipid metabolism, immune system actions, and adipocyte differentiation. Given these important functions, several studies have assessed the nutritional status of selenium to elucidate whether its homeostasis is impaired by excess adiposity, which in turn could contribute to the adipose tissue dysfunction and metabolic disorders. However, the results of these studies are quite controversial. Therefore, this systematic review and meta-analysis aimed to assess differences in the nutritional status of selenium in overweight/obese individuals. METHODS: We searched the PubMed, Scopus, Web of Science, Embase, Cochrane Library, and Virtual Health Library databases. Studies comparing overweight or obese individuals with eutrophic individuals and assessing at least one marker of selenium were included. Comprehensive Meta-Analysis software was used to perform meta-analysis. The effect size was calculated using the raw mean difference or the standardized mean difference, with 95% confidence interval and a p-value of <0.05. Heterogeneity was determined using the I2 index. Subgroup analyses were performed according to sex, body mass index (BMI), and selenium content in the soil. The protocol of this review was registered in the Prospective Register of Systematic Reviews (registration number: CRD42020185405). RESULTS: This systematic review included 73 articles, of which 65 articles were eligible for meta-analysis. There were no significant differences between the overweight/obesity and eutrophy groups in terms of dietary intake and plasma/serum levels of selenium and selenoprotein P levels. The activity of plasma/serum glutathione peroxidase was decreased in the overweight/obese children and adolescents; however, the difference was no statistically significant when the enzyme activity was analyzed in erythrocytes and whole blood. In the adult age group, overweight/obese individuals had decreased activity of both glutathione peroxidase isoforms compared to those individuals with eutrophy. In particular, the activity of erythrocyte glutathione peroxidase was significantly decreased in obese individuals and those living in regions with low-to-moderate selenium content in the soil. Regarding selenium excretion markers, overweight/obese individuals had lower levels of selenium in the urine and nails and a trend of higher levels of selenium in the hair than eutrophic individuals. CONCLUSIONS: In conditions of excess adiposity, the main alteration in the nutritional status of selenium is a decrease in glutathione peroxidase activity, particularly in adults with obesity. In addition, reduced levels of selenium in urine and nails can be found in overweight or obese individuals.


Asunto(s)
Obesidad Infantil , Selenio , Adolescente , Adulto , Índice de Masa Corporal , Niño , Humanos , Estado Nutricional , Sobrepeso
10.
Polymers (Basel) ; 14(4)2022 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-35215701

RESUMEN

Chitin-glucan complex (CGC) hydrogels were fabricated through a freeze-thaw procedure for biopolymer dissolution in NaOH 5 mol/L, followed by a dialysis step to promote gelation. Compared to a previously reported methodology that included four freeze-thaw cycles, reducing the number of cycles to one had no significant impact on the hydrogels' formation, as well as reducing the total freezing time from 48 to 18 h. The optimized CGC hydrogels exhibited a high and nearly spontaneous swelling ratio (2528 ± 68%) and a water retention capacity of 55 ± 3%, after 2 h incubation in water, at 37 °C. Upon loading with caffeine as a model drug, an enhancement of the mechanical and rheological properties of the hydrogels was achieved. In particular, the compressive modulus was improved from 23.0 ± 0.89 to 120.0 ± 61.64 kPa and the storage modulus increased from 149.9 ± 9.8 to 315.0 ± 76.7 kPa. Although the release profile of caffeine was similar in PBS and NaCl 0.9% solutions, the release rate was influenced by the solutions' pH and ionic strength, being faster in the NaCl solution. These results highlight the potential of CGC based hydrogels as promising structures to be used as drug delivery devices in biomedical applications.

11.
Molecules ; 28(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36615513

RESUMEN

Gastric cancer (GC) is one of the major causes of death worldwide, ranking as the fifth most incident cancer in 2020 and the fourth leading cause of cancer mortality. The majority of GC patients are in an advanced stage at the time of diagnosis, presenting a poor prognosis and outcome. Current GC treatment approaches involve endoscopic detection, gastrectomy and chemotherapy or chemoradiotherapy in an adjuvant or neoadjuvant setting. Drug development approaches demand extreme effort to identify molecular mechanisms of action of new drug candidates. Drug repurposing is based on the research of new therapeutic indications of drugs approved for other pathologies. In this review, we explore GC and the different drugs repurposed for this disease.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Terapia Neoadyuvante , Quimioterapia Adyuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estadificación de Neoplasias
12.
Arq. bras. cardiol ; 117(6 supl.1): 14-14, dez., 2021. ilus.
Artículo en Portugués | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1348468

RESUMEN

DESCRIÇÃO DO CASO: Paciente feminina, 29 anos, foi admitida por perda transitória da consciência em decúbito dorsal, sem pródromos e com recuperação espontânea após 5 minutos. Negava dor torácica, dispneia e palpitações. Não foram relatadas comorbidades ou história familiar de morte súbita cardíaca (MSC). O exame físico revelou clique mesossistólico seguido por sopro sistólico mais audível em ápice, com aumento com manobra de handgrip e elevação de membros inferiores e redução com manobra de Valsalva; ECG mostrou ritmo sinusal e ectopias ventriculares (EV) frequentes com morfologia de BRD; Holter de 24h demonstrou 11.331 EV monomórficas e 79 episódios de TVNS polimórfica rápida. Todos os episódios TVNS foram desencadeados por EV com a mesma morfologia com intervalo de acoplamento curto (260ms) (Figura 1); ecocardiograma mostrou FEVE preservada sem alterações da contratilidade miocárdica segmentar, valva mitral espessada com prolapso de ambas as cúspides, disjunção do anel mitral (14mm) e regurgitação mitral leve (Figura 2). Ablação por cateter foi indicada. O mapeamento do ventrículo esquerdo foi realizado com cateter de ponta irrigada, com auxílio de ecocardiograma intracardíaco e sistema eletroanatômico tridimensional, via acesso retroaórtico. A ativação mais precoce foi registrada no músculo papilar posteromedial com potenciais bipolares no cateter de ablação precedendo a EV em 40ms. RF foi aplicada nesta posição com término imediato das arritmias (Figura 3). Holter 24h realizado após 6 meses não mostrou recorrência das arritmias. DISCUSSÃO: O risco estimado de MSC em pacientes com PVM é de 0,2%-0,4%/ano, principalmente associado à presença de arritmias ventriculares. Fatores de risco incluem sexo feminino, comprometimento de ambos os folhetos e disjunção do anel mitral. A ablação por cateter é indicada nos casos em que os gatilhos de TV ou FV podem ser mapeados e identificados ou para TV por reentrada relacionada à fibrose. CONCLUSÃO: Descrevemos um caso de TVNS polimórfica desencadeada por EV com intervalo de acoplamento curto em paciente com PVM. Este caso ilustra a ocorrência de arritmias ventriculares malignas nessa população.


Asunto(s)
Prolapso de la Válvula Mitral , Taquicardia Ventricular , Ablación por Catéter , Complejos Prematuros Ventriculares
13.
Animals (Basel) ; 11(9)2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34573710

RESUMEN

Animal crimes are a widespread phenomenon with serious implications for animal welfare, individual well-being and for society in general. These crimes are universal and represent a major problem in human/animal interaction. In Portugal, current law 69/2014 criminalizes the mistreatment and abandonment of companion animals. This study characterizes forensic cases received at the Laboratory of Pathology of the National Institute of Agrarian and Veterinary Investigation (Vairão) since the enforcement of the aforementioned legislation. A retrospective study was carried out based on the consult of 160 data files of forensic necropsies from 127 dogs and 33 cats. Necropsies confirmed prior crime suspicion in 38 cases (24%), from which 33 were dogs and five were cats. Among confirmed cases, most of assaulted animals were medium-size (57%), crossbreed (55%) male (58%) dogs (87%), which were the victims of blunt force trauma (31%), firearms (27%), poisoning (27%) and asphyxiation (15%). In cats, most of the assaulted animals were juvenile (60%) females (60%) of unknown breed (40%), which suffered blunt force trauma (100%) as the only cause of death. The present study shows that violence against animals is a reality, and complaints about these crimes are gradually increasing due to the population's raising awareness about animal rights. Greater communication and coordination between clinicians, veterinary pathologists, and law enforcement officers are essential to validate and legally support these cases and subject them to trial.

14.
Jpn Dent Sci Rev ; 57: 60-70, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33995712

RESUMEN

The repetitive restorative cycle should be avoided, aiming at the smallest number of restorations' replacements to ensure greater tooth longevity. Antibacterial materials associated with the control of caries etiological factors can help improve restoration's durability. This review aimed to analyze the results of in vitro studies that added Dimethylaminohexadecyl methacrylate (DMAHDM), an antibacterial monomer, to restorative materials. The PubMed, SCOPUS, Web of Science, and Biblioteca Virtual em Saúde databases were screened for studies published between 2015 and 2020. After full-text reading, 24 articles were included in the final sample. DMAHDM has demonstrated antibacterial efficacy against several bacteria related to dental caries and periodontal diseases, causing a transition in the biofilm balance without inducing resistance. When DMAHDM was included in acrylic resin, the material cytotoxicity increased, and changes in mechanical properties were observed. In contrast, resin composites had their mechanical properties maintained in most studies; however, toxicity was not examined. The association between DMAHDM and 2-methacryloyloxyethyl phosphorylcholine or silver nanoparticles improved the antibacterial effect. Besides, the association with nanoparticles of amorphous calcium phosphate or nanoparticles of calcium fluoride can provide remineralization capacity. There is a lack of information on the cytotoxicity and bacteria resistance induction, and further studies are needed to address this.

15.
Rev. Ciênc. Plur ; 7(2): 47-60, maio 2021. ilus, tab
Artículo en Portugués | BBO - Odontología, LILACS | ID: biblio-1282724

RESUMEN

Introdução:As atuaisresinas Bulk-Fill apresentamcomovantagens e propriedades: menor tempo clínico, baixa contração de polimerização, maior translucidez, entre outros. Objetivo:Avaliar a topografia superficial de restaurações com diferentes tipos de resina composta antes e após submetê-las a diferentes sistemas de acabamento e polimento. Metodologia:Confecção de100 corpos de prova, sendo 50 de cada composto resinoso, apresentando cinco grupos (n=10) sorteados de forma aleatória, de acordo com o sistema de acabamento e polimento empregado. Foram utilizadas as resinas Filtek Z350 XT e a Bulk Fill Filtek One Bulk Fill e os sistemas de acabamento e polimento: Discos de Lixa Sof-Lex Pop On Kit;Discos Diamantado Espiral Sof-Lex; Ponta Enhance e Broca Carbide Multilaminada nº 0283F, que foram comparados com superfície deixada pela Tira de Poliester (Controle Negativo). Após 7 dias de armazenamento em água destilada, os corpos de provaforam submetidos aoMicroscópio Eletrônico de Varredura.Resultados:Os corpos de provada resina Bulk Fill tiveram como melhor resultado o sistema de acabamento e polimentocom broca carbidee resultado não satisfatório com discodiamantado espiral Sof-lex, enquanto a ponta Enhance e lixa Sof-lex Pop Ontiveram resultados semelhantes. Os corpos de prova da resina Filtek Z350 XT tiveram melhor aspecto visual de lisura no grupo controle negativoe pior resultado no grupo com disco diamantado espiral Sof-lex. Conclusões:Dessa forma, o sistema que apresentou melhor resultado foi a broca Carbidena resina Bulk Fill, enquanto a Filtek Z350 XT apresentou-se melhor no grupo controle. Porém, ainda são necessáriosestudos para se chegar em um protocolo de acabamento e polimento mais eficiente (AU).


Introduction:The current Bulk-Fill resins have the following advantages and properties: less clinical time, low polymerization shrinkage, greater translucency, among others.Objective:Toevaluate the topography of restorations with different types of composite resin before and after submitting them to different finishing and polishing systems.Methodology:Manufacture of 100 specimens, 50 of each resin compound, presenting five groups (n = 10) drawn at random, according to the finishing and polishing system employed. Filtek Z350 XT resins and Bulk Fill Filtek One Bulk Fill andfinishing and polishing systems were used: Sof-Lex Pop On Kit Sanding Discs; Diamond Spiral Sof-Lex Discs; Tip Enhance and Multilaminated Carbide Drill nº 0283F, which were compared with the surface left by the Polyester Strip (Negative Control). After 7 days of storage in distilled water, the specimens were submitted to a Scanning Electron Microscope.Results:The Bulk Fill resin specimens had the best result of the finishing and polishing system with carbide drill and unsatisfactory result with Sof-lex spiral diamond disc, while the Enhance tip and Sof-lex Pop On sandpaper had similar results. The Filtek Z350 XT resin specimens had a better visual aspect of smoothness in the negative control group and a worse result in the group with Sof-lex spiral diamond wheel.Conclusions:Thus, the system that showed the best result was the Carbide drill in Bulk Fill resin, while Filtek Z350 XT was better in the control group. However, studies are still needed to arrive at a more efficient finishing and polishing protocol (AU).


Introducción:Las actuales resinas Bulk-Fill tienen las siguientes ventajas y propiedades: menor tiempo clínico, baja contracción de polimerización, mayor translucidez, entre otras.Objetivo: Evaluar la topografía de restauraciones con diferentes tipos de resina compuesta antes y después de someterlas a diferentes sistemas de acabado y pulido.Metodología: Fabricación de 100 probetas, 50 de cada resina compuesta, presentando cinco grupos (n = 10) extraídos al azar, según el sistema de acabado y pulido empleado. Se utilizaron resinas Filtek Z350 XT y Bulk Fill Filtek One Bulk Fill y sistemas de acabado y pulido: Discos de lijado Sof-Lex Pop On Kit; Discos Sof-Lex en espiral de diamante; Broca Realce de Punta y Carburo Multilaminado nº 0283F, que fueron comparadas con la superficie dejada por la Tira de Poliéster (Control Negativo). Después de 7 días de almacenamiento en agua destilada, lasmuestras se sometieron a un Las muestras de resina Bulk Fill tuvieron el mejor resultado del sistema de acabado y pulido con broca de carburo y un resultado insatisfactorio con el disco de diamante en espiral Sof-lex, mientras que la punta Enhance y el papel de lija Sof-lex Pop On tuvieron resultados similares. Las muestras de resina Filtek Z350 XT tuvieron un mejor aspecto visual de suavidad en el grupo de control negativo y un peor resultado en el grupo con disco de diamante en espiral Sof-lex.Conclusiones: Así, el sistema que mejor resultado mostró fue la broca Carbide en resina Bulk Fill, mientras que Filtek Z350 XT fue mejor en el grupo control. Sin embargo, aún se necesitan estudios para llegar a un protocolo de acabado y pulido más eficiente (AU).


Asunto(s)
Propiedades de Superficie , Microscopía Electrónica de Rastreo/instrumentación , Resinas Compuestas , Pulido Dental/instrumentación , Técnicas In Vitro/métodos , Brasil , Polimerizacion
16.
Rev. Ciênc. Plur ; 7(2): 61-73, maio 2021. tab
Artículo en Portugués | BBO - Odontología, LILACS | ID: biblio-1282737

RESUMEN

Introdução:Os sistemas adesivos possibilitama execução de restaurações estéticas e minimamente invasivas, sendo, portanto,objeto de pesquisas para contornar os problemas que se apresentam no procedimento restaurador.Objetivo:Avaliar in vitroa resistência de união de um sistema adesivo autocondicionante, e deste modificado com soluções extrativas de semente de uva.Metodologia:Duas soluções extrativas foram preparadas comextrato de semente de uva em pó dissolvido em acetona e etanol. A partir delas e de umadesivo,seis sistemas adesivos autocondicionantes experimentais foram preparados, diferindo quanto aosolvente utilizado eàsproporções entre adesivo puro e solução extrativa(7,5%, 15% e 30%). Setenta incisivos bovinos hígidos tiveram as raízes removidas com disco de carborundum e as faces vestibulares desgastadas comlixas d'água de granulação 120, 240, 600 e 1200 sob refrigeração até expor a dentina superficial. Os dentes foram distribuídos aleatoriamenteem sete grupos distintos: Controle; A7,5; A15; A30; E7,5; E15; e E30, contendo 10 elementos cada. A aplicação dos adesivos foi executada de acordo com as recomendações do fabricante do adesivo controle. A restauração foi realizada com uma matriz de silicone com dimensões 2mm de altura e 4mm de diâmetro e inserido o material restaurador em incremento único e fotopolimerizado por 40s. Após três meses armazenados em água destilada, os espécimes foram submetidos ao teste de resistência de união. Foi empregado ométodo estatísticoTeste Paramétrico Anova 1 Fator e pós-teste de Tamhane (p<0,05). Resultados:Os grupos A7,5, E7,5 e E30 não apresentaram diferença em relação ao grupo Controle; A15 e A30 mostraram desempenho estatisticamente semelhante entre si; e E15 não apresentou diferença estatística em relação aos outros adesivos.Conclusões:A adição de proantocianidina teve efeitos diferentes,dependendodos solventes e das concentrações utilizadas, mas sem alterar significativamente o desempenho do adesivo (AU).


Introduction:Adhesive systems make it possible to perform aestheticand minimally invasive restorations, being the subject of research to circumvent the problems that arise in the restorative procedure.Objective:Evaluate in vitrothe bond strength of a self-etching adhesive system,and modified with extractive grape seed solutions. Methodology:Two extractive solutions were prepared with powdered grape seed extract dissolved in acetone and ethanol. From them and an adhesive, six experimental self-etching adhesive systems were prepared, differing in terms of the solvent used and the proportions between pure adhesive and extractive solution(7.5%, 15% and 30%). Seventy healthy bovine incisors had their roots removed with carborundum disc and the vestibular faces were worn with sandpaper with granulation water 120, 240, 600 and 1200 under refrigeration until the superficial dentin was exposed. The teeth were randomly assigned to seven different groups: Control; A7.5; A15; A30; E7.5; E15; and E30, containing 10 elements each. The application of the adhesives was carried out according to the recommendations of the manufacturer of the control adhesive. The restoration was performed with a silicone matrix with dimensions 2mm high and 4mm indiameter and the restorative material was inserted in a single increment and light cured for 40s. After three months stored in distilled water, the specimens were submitted to the bond strength test. The statistical method Parametric Test Anova 1 Factor and Tamhane post-test (p<0.05) were used. Results:Groups A7.5, E7.5 and E30 showed no difference in relation to the Control group; A15 and A30 showed a statistically similar performance; and E15 showed no statistical difference in relation to the other adhesives. Conclusions:The addition of proanthocyanidin had different effects, depending on the solvents and concentrations used, but without significantly altering the performance ofthe adhesive (AU).


Introducción: Sistemas adhesivos permiten realizar restauraciones estéticas y mínimamente invasivas, siendo objeto de investigación para sortear problemas que surgen en elprocedimiento restaurador. Objetivo: Evaluar in vitrola fuerza de unión de un sistema adhesivoautograbante y modificado con soluciones extractivas de semilla de uva. Metodología: Se prepararon dos soluciones extractivas con extracto de semilla de uva en polvo disuelto en acetona y etanol. A partir de ellos y de un adhesivo, se prepararon seis sistemas experimentales de adhesivos autograbantes, que se diferencian en cuanto al solvente utilizado y las proporciones entre adhesivo puro y solución extractiva (7,5%, 15% y 30%). Setenta incisivos bovinos sanos fueron removidos con un disco de carborundo y las caras vestibulares fueron usadas com lija de agua de granulación 120, 240, 600 y 1200 bajo refrigeración hasta que la dentina superficial quedo expuesta. Los dientes se asignaron aleatoriamente a siete grupos diferentes: Control; A7,5; A15; A30; E7,5; E15; y E30, que contiene 10 elementos cada uno. La aplicación de los adhesivos se realizó siguiendo las recomendaciones del fabricante del adhesivo de control. La restauración se realizó con matriz de silicona con 2mm de altura y 4mm de diámetro y el material restaurador se insertó en un solo incremento y se fotopolimerizó durante 40s. Tres meses después, almacenados em agua destilada, las muestras se sometieron a la prueba de resistencia de la unión. Se utilizó el método estadístico Prueba Paramétrica Factor Anova 1 y post-prueba de Tamhane (p<0,05). Resultados: Los grupos A7,5, E7,5 y E30 no mostraron diferencias em relación con el grupo Control; A15 y A30 mostraron un desempeño estadísticamente similar; y E15 no mostró diferencia estadística en relación con los otros adhesivos. Conclusiones: La adición de proantocianidina tuvo diferentes efectos, dependiendo de los disolventes y concentraciones utilizadas, pero sin alterar significativamente el rendimiento del adhesivo (AU).


Asunto(s)
Animales , Bovinos , Pulido Dental/instrumentación , Proantocianidinas , Resistencia Flexional , Solventes , Técnicas In Vitro/métodos , Brasil , Análisis de Varianza , Cementos Dentales/química , Extracto de Semillas de Uva
17.
Int J Biol Macromol ; 167: 85-92, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33249156

RESUMEN

Pseudomonas chlororaphis subsp. aurantiaca DSM 19603 was cultivated on apple pulp, a glucose- and fructose-rich waste generated during juice production, to produce medium-chain length polyhydroxyalkanoates. A cell dry mass of 8.74 ± 0.20 g/L, with a polymer content of 49.25 ± 4.08% were attained. The produced biopolymer was composed of 42.7 ± 0.1 mol% 3-hydroxydecanoate, 17.9 ± 1.0 mol% 3-hydroxyoctanoate, 14.5 ± 1.1 mol% 3-hydroxybutyrate, 11.1 ± 0.6 mol% 3-hydroxytetradecanoate, 10.1 ± 0.5 mol% 3-hydroxydodecanoate and 3.7 ± 0.2 mol% 3-hydroxyhexanoate. It presented low glass transition and melting temperatures (-40.9 ± 0.7 °C and 42.0 ± 0.1 °C, respectively), and a degradation temperature of 300.0 ± 0.1 °C, coupled to a low crystallinity index (12.7 ± 2.7%), a molecular weight (Mw) of 1.34 × 105 ± 0.18 × 105 Da and a polydispersity index of 2.70 ± 0.03. The biopolymer's films were dense and had a smooth surface, as demonstrated by Scanning Electron Microscopy. They presented a tension at break of 5.21 ± 1.09 MPa, together with an elongation of 400.5 ± 55.8% and an associated Young modulus of 4.86 ± 1.49 MPa, under tensile tests. These attractive filming properties of this biopolymer could potentially be valorised in several areas such as the fine chemicals industry, biomedicine, pharmaceuticals, or food packaging.


Asunto(s)
Biopolímeros/química , Fermentación , Frutas/química , Polihidroxialcanoatos/biosíntesis , Pseudomonas/metabolismo , Residuos , Reactores Biológicos , Fraccionamiento Químico , Fenómenos Químicos , Cinética , Malus , Fenómenos Mecánicos , Peso Molecular , Polihidroxialcanoatos/química , Polihidroxialcanoatos/aislamiento & purificación
18.
Suma psicol ; 27(2): 125-141, jul.-dic. 2020. tab, graf
Artículo en Español | LILACS, Index Psicología - Revistas, COLNAL | ID: biblio-1145122

RESUMEN

Resumen El cáncer de cuello uterino es la cuarta causa de cáncer en mujeres, siendo el virus del papiloma humano (VPH) su mayor factor de riesgo. Este virus produce, además, otros tipos de cáncer e infecciones que afectan a hombres y a mujeres. La vacuna del VPH ha mostrado eficacia y seguridad en su prevención, sin embargo, se han evidenciado barreras que disminuyen su aceptación en las comunidades. El objetivo de este estudio es identificar las estrategias más efectivas en la intervención comunitaria con el fin de mejorar la aceptabilidad de la vacunación contra el VPH. Se realizó una revisión sistemática en Cochrane, Scopus, Embase, Medline y Google Académico de junio a julio de 2019, sin restricciones temporales, en idioma inglés y español. Se incluyeron ensayos clínicos que evaluaran estrategias para mejorar la vacunación contra el VPH. Se revisaron 22 estudios que evaluaban estrategias de intervención comunitaria y se identificaron, principalmente tres: el uso de información y formación de tipo virtual, el involucramiento tanto de padres, madres o cuidadores como del personal sanitario, así como el involucramiento de los hombres y de las personas de orientación sexual diversa como población objetivo.


Abstract Cervical cancer is the fourth leading cause of cancer in women, with the human papillomavirus (HPV) being its major risk factor. This virus also produces other types of cancer and infections that affect men and women. The HPV vaccine has shown efficacy and safety in its prevention, however, barriers have been evident that decrease its acceptance in communities. The objective of this study is to identify the most effective strategies in community intervention to improve the acceptability of HPV vaccination. A systematic review was conducted in Cochrane, Scopus, Embase, Medline, and Google Scholar from June to July 2019, without time constraints, in English and Spanish. We included clinical trials evaluating strategies to improve HPV vaccination. We reviewed 22 studies evaluating community intervention strategies, and identified mainly three: the use of virtual information and training, involvement of parents and/or caregivers as well as health personnel, and involvement of men and people of diverse sexual orientation as a target population.


Asunto(s)
Alphapapillomavirus , Neoplasias del Cuello Uterino , Infecciones por Papillomavirus , Vacunas contra Papillomavirus
19.
Carbohydr Polym ; 247: 116679, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32829807

RESUMEN

This work explores the novelty of dissolving chitin-glucan complex (CGC), from two fungal strains, Komagataella pastoris (CGCP) and Aspergillus niger (CGCKZ) (KiOnutrime-CG™), using biocompatible ionic liquids (ILs). Three cholinium-based ILs were tested, choline acetate, choline propionate and choline hexanoate. Although all tested ILs resulted in the dissolution of the co-polymer at a concentration of 5 % (w/w), distinct polymeric structures, films or gels, were obtained from CGCP and CGCKZ, respectively. CGCP films were dense, flexible and elastic, with high swelling capacity (> 200 %). The IL anion alkyl chain length influenced the polymeric structures' properties, namely, the CGCP films elongation at break and swelling degree. CGCKZ resulted in weak gels. For both polymeric structures, exposure to the ILs under the dissolution conditions caused significant changes in the co-polymers' chemical structure, namely, reduction of their glucan moiety and reduction of the degree of acetylation, thus yielding chitosan-glucan complexes (ChGC) enriched in glucosamine (53.4 ± 0.3-60.8 ± 0.3 %).


Asunto(s)
Biopolímeros/química , Quitina/química , Quitina/aislamiento & purificación , Glucanos/química , Glucanos/aislamiento & purificación , Líquidos Iónicos/química , Acetilación , Aspergillus niger/química , Colina/análogos & derivados , Colina/química , Geles/química , Glucosamina/química , Microscopía Electrónica de Rastreo , Oscilometría , Reología , Saccharomycetales/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Agua/química
20.
Bioengineering (Basel) ; 7(1)2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32183337

RESUMEN

Chitin-glucan complex (CGC) is a copolymer composed of chitin and glucan moieties extracted from the cell-walls of several yeasts and fungi. Despite its proven valuable properties, that include antibacterial, antioxidant and anticancer activity, the utilization of CGC in many applications is hindered by its insolubility in water and most solvents. In this study, NaOH/urea solvent systems were used for the first time for solubilization of CGC extracted from the yeast Komagataella pastoris. Different NaOH/urea ratios (6:8, 8:4 and 11:4 (w/w), respectively) were used to obtain aqueous solutions using a freeze/thaw procedure. There was an overall solubilization of 63-68%, with the highest solubilization rate obtained for the highest tested urea concentration (8 wt%). The regenerated polymer, obtained by dialysis of the alkali solutions followed by lyophilization, formed porous macrostructures characterized by a chemical composition similar to that of the starting co-polymer, although the acetylation degree decreased from 61.3% to 33.9-50.6%, indicating that chitin was converted into chitosan, yielding chitosan-glucan complex (ChGC). Consistent with this, there was a reduction of the crystallinity index and thermal degradation temperature. Given these results, this study reports a simple and green procedure to solubilize CGC and obtain aqueous ChGC solutions that can be processed as novel biomaterials.

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