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1.
Int J Nanomedicine ; 19: 9091-9107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258003

RESUMO

Purpose: Castration Resistant Prostate Cancer (CRPC) is characterized by poor prognosis and limited therapeutic options. AgNPs functionalized with glucose (G-AgNPs) were observed cytotoxic to CRPC cell lines (PC-3 and Du-145) and not LNCaP. This study aims to evaluate AgNPs and G-AgNPs' uptake mechanisms in these cells and understand their role in the selective effect against CRPC cells. Methods: Uptake of AgNPs and G-AgNPs was assessed through transmission electron microscopy (TEM). A microRNA (miRNAs) analysis approach was used to uncover the main molecular differences responsible for the endocytic mechanisms' regulation. Caveolin (Cav) 1 and 2 mRNA and protein levels were assessed in the three cell lines. Caveolae-dependent endocytosis was inhibited with genistein or siCav1- and siCav2- in PC-3 and Du-145 and resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration. Caveolae-dependent endocytosis was induced with Cav1+ and Cav2+ plasmids in LNCaP, resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration and TEM to assess their location. Results: AgNPs and G-AgNPs were not uptaked by LNCaP. miRNA analysis revealed 37 upregulated and 90 downregulated miRNAs. Functional enrichment analysis of miRNAs' targets resulted in enrichment of terms related to endocytosis and caveolae. We observed that Cav1 and Cav2 are not expressed in LNCaP. Inhibiting caveolae-dependent endocytosis in Du-145 and PC-3 led to a significative reduction of cytotoxic capacity of AgNPs and G-AgNPs and induction of caveolae-dependent endocytosis in LNCaP lead to a significative increase as well as their uptake by cells. Conclusion: This study shows the potential of these AgNPs as a new therapeutic approach directed to CRPC patients, uncovers caveolae-dependent endocytosis as the uptake mechanism of these AgNPs and highlights deregulation of Cav1 and Cav2 expression as a key difference in hormone sensitive and resistant PCa cells which may be responsible for drug resistance.


Assuntos
Cavéolas , Caveolina 1 , Endocitose , Nanopartículas Metálicas , MicroRNAs , Neoplasias de Próstata Resistentes à Castração , Prata , Masculino , Humanos , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Cavéolas/metabolismo , Cavéolas/efeitos dos fármacos , Prata/química , Prata/farmacologia , Prata/farmacocinética , Caveolina 1/metabolismo , Caveolina 1/genética , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , MicroRNAs/metabolismo , MicroRNAs/genética , Sobrevivência Celular/efeitos dos fármacos , Caveolina 2/metabolismo , Caveolina 2/genética , Antineoplásicos/farmacologia , Células PC-3
2.
Int J Pharm ; 660: 124354, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38897486

RESUMO

During recent years there have been shortages of certain drugs due to problems in raw material supply. These are often related to active ingredients but could also affect excipients. Lactose is one of the most used excipients in tableting and comes in two anomeric and several solid-state forms. The aim of this study was to utilize lactose from a dairy side-stream and compare it against a commercial reference in direct compression. This would be a sustainable option and would secure domestic availability during crises. Two types of lactose, spray-dried and freeze-dried, were evaluated. Lactose was mixed with microcrystalline cellulose in different ratios together with lubricant and glidant, and flowability and tabletability of the formulations was characterized. The fully amorphous and small particle-sized spray-dried lactose flowed inadequately but exhibited good tabletability. The larger particle-sized, freeze-dried lactose exhibited sufficient flow and better tabletability than the commercial reference. However, disintegration and drug release were slower when using the investigational lactose formulations. This was most likely due to remaining milk proteins, especially caseins, in the lactose. Overall, the investigational lactose provides promise for the use of such a side-stream product during crisis situations but enhancing their properties and/or purity would be needed.


Assuntos
Celulose , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Liofilização , Lactose , Comprimidos , Lactose/química , Excipientes/química , Celulose/química , Composição de Medicamentos/métodos , Estudo de Prova de Conceito , Tamanho da Partícula , Secagem por Atomização , Indústria de Laticínios , Química Farmacêutica/métodos
3.
Carbohydr Polym ; 339: 122242, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823911

RESUMO

Glucuronoxylans (GX), particularly crude fractions obtained by pressurized hot water extraction of birch wood, act as potent emulsifiers and stabilizers against physical separation and lipid oxidation. Herein, we studied the adsorption of GX on hydrophobic interfaces to correlate their multicomponent character towards the formation of interfacial layers in emulsions. Dynamic interfacial tension (DIFT) and quartz crystal microgravimetry with dissipation monitoring (QCM-D) were applied to various GX fractions and the results compared with those from cellulose-based emulsifiers. The roles of residual lignin and polysaccharides are discussed considering the formation of interfacial layers during emulsification. The DIFT of the different GXs reached quasi-equilibrium faster as the lignin concentration increased, implying a correlation between the rate of adsorption and the residual lignin content. The effect of NaCl addition was more pronounced in polysaccharide-rich fractions, indicating that the polysaccharide fraction modulated the effect of ionic strength. QCM-D showed that despite the fast adsorption exhibited by the lignin-rich GX extract in the DIFT curves, the adsorbed materials were lightweight, suggesting that the polysaccharide fraction built the bulk of the interfacial layer. These results provide a foundation towards understanding the role of GX in interfacial stabilization beyond traditional plant-based counterparts.

4.
Int J Biol Macromol ; 266(Pt 1): 131168, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552694

RESUMO

Pharmaceuticals, designed for treating diseases, ironically endanger humans and aquatic ecosystems as pollutants. Adsorption-based wastewater treatment could address this problem, however, creating efficient adsorbents remains a challenge. Recent efforts have shifted towards sustainable bio-based adsorbents. Here, cryogels from lignin-containing cellulose nanofibrils (LCNF) and lignin nanoparticles (LNPs) were explored as pharmaceuticals adsorbents. An enzyme-based approach using laccase was used for crosslinking instead of fossil-based chemical modification. The impact of laccase treatment on LNPs alone produced surface-crosslinked water-insoluble LNPs with preserved morphology and a hemicellulose-rich, water-soluble LNP fraction. The water-insoluble LNPs displayed a significant increase in adsorption capacity, up to 140 % and 400 % for neutral and cationic drugs, respectively. The crosslinked cryogel prepared by one-pot incubation of LNPs, LCNF and laccase showed significantly higher adsorption capacities for various pharmaceuticals in a multi-component system than pure LCNF or unmodified cryogels. The crosslinking minimized the leaching of LNPs in water, signifying enhanced binding between LNPs and LCNF. In real wastewater, the laccase-modified cryogel displayed 8-44 % removal for cationic pharmaceuticals. Overall, laccase treatment facilitated the production of bio-based adsorbents by improving the deposition of LNPs to LCNF. Finally, this work introduces a sustainable approach for engineering adsorbents, while aligning with global sustainability goals.


Assuntos
Celulose , Criogéis , Lacase , Lignina , Nanopartículas , Poluentes Químicos da Água , Adsorção , Criogéis/química , Lignina/química , Lacase/química , Celulose/química , Nanopartículas/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Preparações Farmacêuticas/química , Águas Residuárias/química , Reagentes de Ligações Cruzadas/química
5.
J Agric Food Chem ; 72(7): 3495-3505, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38343302

RESUMO

Birch wood-derived fiber extracts containing glucuronoxylans (GX) and polyphenols show potential for various food technological applications. This study investigated the effect of two extracts, GXpoly and pureGX, differing in lignin content on colonic barrier function. Healthy rats were fed diets containing 10% GXpoly, pureGX, or cellulose for 4 weeks. Colon crypt depth was lower in the GX groups than in the control group, but in the proximal colon, the result was significant only in GXpoly. An artificial intelligence approach was established to measure the mucus content and goblet cells. In the distal colon, their amounts were higher in the control group than in the GX groups. All diets had a similar effect on the expression of the tight junction proteins occludin, claudin-1, and claudin-7. GXpoly enhanced the fecal IgA production. Our results suggest that GX-rich extracts could support the colonic barrier and work as functional food ingredients in the future.


Assuntos
Betula , Colo , Xilanos , Ratos , Animais , Colo/metabolismo , Mucosa Intestinal/metabolismo , Polifenóis/metabolismo , Inteligência Artificial , Madeira , Proliferação de Células
6.
Antioxidants (Basel) ; 12(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38136171

RESUMO

Nanomedicine's advent has promised to revolutionize different biomedical fields, including oncology. Silver Nanoparticles (AgNPs) showed promising results in different tumor models. Clear cell Renal Cell Carcinoma (ccRCC) is especially challenging due to its late diagnosis, poor prognosis and treatment resistance. Therefore, defining new therapeutic targets and regimens could improve patient management. This study intends to evaluate AgNPs' effect in ccRCC cells and explore their potential combinatory effect with Everolimus and Radiotherapy. AgNPs were synthesized, and their effect was evaluated regarding their entering pathway, cellular proliferation capacity, ROS production, mitochondrial membrane depolarization, cell cycle analysis and apoptosis assessment. AgNPs were combined with Everolimus or used to sensitize cells to radiotherapy. AgNPs are cytotoxic to 786-O cells, a ccRCC cell line, entering through endocytosis, increasing ROS, depolarizing mitochondrial membrane, and blocking the cell cycle, leading to a reduction of proliferation capacity and apoptosis. Combined with Everolimus, AgNPs reduce cell viability and inhibit proliferation capacity. Moreover, 786-O is intrinsically resistant to radiation, but after AgNPs' administration, radiation induces cytotoxicity through mitochondrial membrane depolarization and S phase blockage. These results demonstrate AgNPs' cytotoxic potential against ccRCC and seem promising regarding the combination with Everolimus and sensitization to radiotherapy, which can, in the future, benefit ccRCC patients' management.

7.
Shoulder Elbow ; 15(4 Suppl): 3-14, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37974609

RESUMO

Background: Patients with paraplegia often experience chronic shoulder pain due to overuse. We sought to determine if these patients have an increased prevalence of perioperative complications and higher rates of re-admissions and rotator cuff re-tears relative to able-bodied controls following rotator cuff repair (RCR). Methods: We queried the NRD (2011-2018) to identify all patients undergoing primary RCR (n = 34,451) and identified cohorts of matched paraplegic and non-paraplegic patients (n = 194 each). We compared demographic factors, comorbidity profiles, perioperative complication rates, length of stay, revision rates, and re-admission rates between the two groups. Results: Patients with paraplegia had lower rates of chronic obstructive pulmonary disease (p = 0.02), hypertension (p = 0.007), congestive heart failure (p = 0.027), obesity (p < 0.001), and prior myocardial infarction (p = 0.01). Additionally, patients with paraplegia experienced higher rates of urinary tract infections (11.9% vs. 2.1%, p < 0.001), lower rates of acute respiratory distress syndrome (0% vs. 3.1%, p = 0.041), and had a longer length of stay (4-days vs. 1-day, p < 0.001). Revision rates were similar for the two groups. Conclusions: Compared to matched controls, patients with paraplegia were found to have similar demographic characteristics, less comorbidities, similar perioperative complication rates, and similar revision rates. These findings address a gap in the literature regarding surgical management of shoulder pain in patients with paraplegia by providing a matched comparison with a large sample size.

8.
Carbohydr Polym ; 321: 121316, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739540

RESUMO

Galactoglucomannans (GGM) recovered from abundant forest industry side-streams has been widely recognized as a renewable hydrocolloid. The low molar mass and presence of O-acetyl side-groups results in low viscous dispersions and weak intermolecular interactions that make GGM unsuitable for hydrogel formation, unless forcefully chemically derivatized and/or crosslinked with other polymers. Here we present the characterization of hydrogels prepared from GGM after tailoring the degree of acetylation by alkaline treatment during its recovery. Specifically, we investigated gel characteristics of low-acetyl GGM dispersions prepared at varied solid concentrations (5, 10 and 15 %) and pH (4, 7 and 10), and then subjected to ultrasonication. The results indicated that low-acetyl GGM dispersions formed gels (G' > G″) at all other studied solid concentration and pH level combinations except 5 % and pH 4. High pH levels, leading to further removal of acetyl groups, and high solid concentration facilitated the gel formation. GGM hydrogels were weak gels with strong shear-thinning behavior and thixotropic properties, and high hardness and water holding capacity; which were enhanced with increased pH and solid concentration, and prolonged storage time. Our study showed the possibility to utilize low-acetyl GGM as mildly processed gelling or thickening agents, and renewable materials for bio-based hydrogels.


Assuntos
Hidrogéis , Picea , Mananas , Acetilação , Dureza
9.
Cellulose (Lond) ; 30(14): 8955-8971, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736116

RESUMO

Nanocellulose is very hydrophilic, preventing interactions with the oil phase in Pickering emulsions. This limitation is herein addressed by incorporating lignin nanoparticles (LNPs) as co-stabilizers of nanocellulose-based Pickering emulsions. LNP addition decreases the oil droplet size and slows creaming at pH 5 and 8 and with increasing LNP content. Emulsification at pH 3 and LNP cationization lead to droplet flocculation and rapid creaming. LNP application for emulsification, prior or simultaneously with nanocellulose, favors stability given the improved interactions with the oil phase. The Pickering emulsions can be freeze-dried, enabling the recovery of a solid macroporous foam that can act as adsorbent for pharmaceutical pollutants. Overall, the properties of nanocellulose-based Pickering emulsions and foams can be tailored by LNP addition. This strategy offers a unique, green approach to stabilize biphasic systems using bio-based nanomaterials without tedious and costly modification procedures. Supplementary Information: The online version contains supplementary material available at 10.1007/s10570-023-05399-y.

10.
Mol Nutr Food Res ; 67(20): e2300201, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37650878

RESUMO

SCOPE: While previously considered inert, recent studies suggest lignin metabolism with unknown metabolic fates is occurring in the gastrointestinal tract of several animal models. This study focuses on analyzing the potential metabolites of lignin. METHODS AND RESULTS: The diets of rats include relatively pure birch glucuronoxylan (pureGX) with residual lignin or lignin-rich GX (GXpoly) in their diet. Nuclear magnetic spectroscopy of the lignin isolated from the GXpoly-fed rats fecal sample shows high alteration in chemical structure, whereas lignin-carbohydrate complexes (LCCs) are enriched in fecal samples from the pureGX group. Moreover, the increased syringyl-to-guaiacyl (S/G) ratio suggests that lignin G-units are predominantly metabolized based on pyrolysis gas chromatography-mass spectrometry (pyr-GC/MS). The presence of small phenolic metabolites identified in urine samples of the GXpoly group, for example, ferulic and sinapic acids, their sulfate and glucuronide derivatives, and 4-sulfobenzylalcohol, suggests that the small fragmented lignin metabolites in the large intestine enter the plasma, and are further processed in the liver. Finally, the relative abundances of polyphenol-degrading Enterorhabdus and Akkermansia in the gut microbiota are associated with lignin metabolism. CONCLUSION: These findings give further evidence to lignin metabolism in the gut of nonruminants and provide insight to the potential microbes and metabolic routes.


Assuntos
Betula , Lignina , Ratos , Animais , Lignina/química , Lignina/metabolismo , Betula/metabolismo , Fibras na Dieta , Xilanos
11.
J Microbiol Methods ; 212: 106794, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37541446

RESUMO

Mycelium-based materials have attracted growing interest, facilitating their development for various new applications. Finding for suitable fungal species and strains enables further technical breakthroughs in their development and quality control. Here, we developed a model solid-state culture system to screen fungal strains efficiently for mycelium-based materials production. A piece of silicone-coated paper set on the general agar plate allows for isolation of the mycelial mat from the substrate. The mycelial growth and density can be evaluated by weighing the mycelial mat. We used the paper substrate after fungal incubation to investigate the relationship between substrate degradation and the contact time with hyphae. It yielded further insights into the fungal decay. Ten basidiomycetes were assessed for their fungal growth and degradation behaviour of the substrate using this method. Pleurotus floridanus FBCC375 showed a dense and elastic mycelial mat and mild degradation of the substrate. A unique decay behaviour was found in Hypsizygus ulmarius FBCC573 and Trametes versicolor FBCC564. They indicated a positional imbalance in the decay activity within the colony. This simple method is helpful for screening fungal strains and facilitates the further development of mycelium-based materials.


Assuntos
Micélio , Trametes , Ágar/metabolismo
12.
J Orthop Surg Res ; 18(1): 442, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340426

RESUMO

INTRODUCTION: Open reduction internal fixation (ORIF) and intramedullary nail fixation (IMN) are the predominant repair methods for operative treatment of humeral diaphyseal fractures; however, the optimal method is not fully elucidated. The purpose of this study was to analyze whether IMN or ORIF humeral diaphyseal surgeries result in a significantly higher prevalence of adverse outcomes and whether these outcomes were age dependent. We hypothesize there is no difference in reoperation rates and complications between IMN and ORIF for humeral diaphyseal fractures. METHODS: Data collected from 2015 to 2017 from the Nationwide Readmissions Database were evaluated to compare the prevalence of six adverse outcomes: radial nerve palsy, infections, nonunion, malunion, delayed healing, and revisions. Patients treated for a primary humeral diaphyseal fracture with either IMN or ORIF were matched and compared (n = 2,804 pairs). Patients with metastatic cancer were excluded. RESULTS: Following an ORIF procedure, there was a greater odds of undergoing revision surgery (p = 0.03) or developing at least one of the complications of interest (p = 0.03). In the age-stratified analysis, no significant differences were identified in the prevalence of adverse outcomes between the IMN and ORIF cohorts in the 0-19, 20-39, and 40-59 age groups. Patients who were 60 + had 1.89 times the odds of experiencing at least one complication and 2.04 times the odds of undergoing a revision after an ORIF procedure versus an IMN procedure (p = 0.03 for both). DISCUSSION: IMN and ORIF for humeral diaphyseal fractures are comparable in regard to complications revision rates in patients under the age of 60. Meanwhile, patients 60 + years show a statistically significant increase in the odds of undergoing revision surgery or experiencing complications following an ORIF. Since IMN appears to be more beneficial to older patients, being 60 + years old should be considered when determining fracture repair techniques for patients presenting with primary humeral diaphyseal fractures.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Úmero , Humanos , Pessoa de Meia-Idade , Readmissão do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Fixadores Internos/efeitos adversos , Redução Aberta/efeitos adversos , Redução Aberta/métodos , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Fraturas do Úmero/cirurgia , Fixação Intramedular de Fraturas/efeitos adversos , Fixação Intramedular de Fraturas/métodos , Úmero , Resultado do Tratamento , Estudos Retrospectivos , Placas Ósseas/efeitos adversos , Pinos Ortopédicos/efeitos adversos
13.
Food Res Int ; 164: 112333, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737926

RESUMO

The most commonly-used and effective wall materials (WMs) for spray-dried microencapsulation of bioactive compounds are either costly, or derived from unsustainable sources, which lead to an increasing demand for alternatives derived from sustainable and natural sources, with low calories and low cost. Wood hemicelluloses obtained from by-products of forest industries appear to be attractive alternatives as they have been reported to have good emulsifying properties, low viscosity at high concentrations, high heat stability and low heat transfer. Here, we investigated the applicability of spruce galactoglucomannans (GGM) and birch glucuronoxylans (GX), to encapsulate flaxseed oil (FO, polyunsaturated fatty acid-rich plant based oil) by spray drying; and the results were compared to those of the highly effective WM, gum Arabic (GA). It was found that depending on solid ratios of WM:FO (1:1, 3:1 and 5:1), encapsulation efficiency of GGM was 88-96%, and GX was 63-98%. At the same encapsulation ratio, both GGM and GX had higher encapsulation efficiency than GA (49-92%) due to their ability to produce feed emulsions with a smaller oil droplet size and higher physical stability. In addition, the presence of phenolic residues in GGM and GX powders enabled them to have a greater ability to protect oil from oxidation during spray drying than GA. Physiochemical properties of encapsulated powders including thermal properties, morphology, molecular structure, particle size and water adsorption intake are also investigated. The study has explored a new value-added proposition for wood hemicelluloses which can be used as effective WMs in the production of microcapsules of polyunsaturated fatty acid-rich oils for healthy and functional products in food, pharmaceutical and cosmetic industries.


Assuntos
Dessecação , Madeira , Pós , Dessecação/métodos , Óleos de Plantas/química , Ácidos Graxos Insaturados
14.
J Agric Food Chem ; 71(6): 2667-2683, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36724217

RESUMO

A holistic utilization of all lignocellulosic wood biomass, instead of the current approach of using only the cellulose fraction, is crucial for the efficient, ecological, and economical use of the forest resources. Use of wood constituents in the food and feed sector is a potential way of promoting the global economy. However, industrially established food products utilizing such components are still scarce, with the exception of cellulose derivatives. Hemicelluloses that include xylans and mannans are major constituents of wood. The wood hemicelluloses are structurally similar to hemicelluloses from crops, which are included in our diet, for example, as a part of dietary fibers. Hence, structurally similar wood hemicelluloses have the potential for similar uses. We review the current status and future potential of wood hemicelluloses as food ingredients. We include an inventory of the extraction routes of wood hemicelluloses, their physicochemical properties, and some of their gastrointestinal characteristics, and we also consider the regulatory route that research findings need to follow to be approved for food solutions, as well as the current status of the wood hemicellulose applications on that route.


Assuntos
Ingredientes de Alimentos , Ingredientes de Alimentos/análise , Madeira/química , Polissacarídeos/química , Celulose/química
15.
J Environ Manage ; 330: 117210, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36608603

RESUMO

Adsorption is a relatively simple wastewater treatment method that has the potential to mitigate the impacts of pharmaceutical pollution. This requires the development of reusable adsorbents that can simultaneously remove pharmaceuticals of varying chemical structure and properties. Here, the adsorption potential of nanostructured wood-based adsorbents towards different pharmaceuticals in a multi-component system was investigated. The adsorbents in the form of macroporous cryogels were prepared by anchoring lignin nanoparticles (LNPs) to the nanocellulose network via electrostatic attraction. The naturally anionic LNPs were anchored to cationic cellulose nanofibrils (cCNF) and the cationic LNPs (cLNPs) were combined with anionic TEMPO-oxidized CNF (TCNF), producing two sets of nanocellulose-based cryogels that also differed in their overall surface charge density. The cryogels, prepared by freeze-drying, showed layered cellulosic sheets randomly decorated with spherical lignin on the surface. They exhibited varying selectivity and efficiency in removing pharmaceuticals with differing aromaticity, polarity and ionic characters. Their adsorption potential was also affected by the type (unmodified or cationic), amount and morphology of the lignin nanomaterials, as well as the pH of the pharmaceutical solution. Overall, the findings revealed that LNPs or cLNPs can act as functionalizing and crosslinking agents to nanocellulose-based cryogels. Despite the decrease in the overall positive surface charge, the addition of LNPs to the cCNF-based cryogels showed enhanced adsorption, not only towards the anionic aromatic pharmaceutical diclofenac but also towards the aromatic cationic metoprolol (MPL) and tramadol (TRA) and neutral aromatic carbamazepine. The addition of cLNPs to TCNF-based cryogels improved the adsorption of MPL and TRA despite the decrease in the net negative surface charge. The improved adsorption was attributed to modes of removal other than electrostatic attraction, and they could be π-π aromatic ring or hydrophobic interactions brought by the addition of LNPs or cLNPs. However, significant improvement was only found if the ratio of LNPs or cLNPs to nanocellulose was 0.6:1 or higher and with spherical lignin nanomaterials. As crosslinking agents, the LNPs or cLNPs affected the rheological behavior of the gels, and increased the firmness and decreased the water holding capacity of the corresponding cryogels. The resistance of the cryogels towards disintegration with exposure to water also improved with crosslinking, which eventually enabled the cryogels, especially the TCNF-based one, to be regenerated and reused for five cycles of adsorption-desorption experiment for the model pharmaceutical MPL. Thus, this study opened new opportunities to utilize LNPs in providing nanocellulose-based adsorbents with additional functional groups, which were otherwise often achieved by rigorous chemical modifications, at the same time, crosslinking the nanocellulose network.


Assuntos
Poluentes Ambientais , Nanopartículas , Poluentes Químicos da Água , Lignina/química , Criogéis/química , Celulose , Água , Adsorção , Poluentes Químicos da Água/química
16.
Appl Environ Microbiol ; 89(1): e0186322, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36645281

RESUMO

Microbial expansin-related proteins are ubiquitous across bacterial and fungal organisms and reportedly play a role in the modification and deconstruction of cell wall polysaccharides, including lignocellulose. So far, very few microbial expansin-related proteins, including loosenins and loosenin-like (LOOL) proteins, have been functionally characterized. Herein, four LOOLs encoded by Phanerochaete carnosa and belonging to different subfamilies (i.e., PcaLOOL7 and PcaLOOL9 from subfamily A and PcaLOOL2 and PcaLOOL12 from subfamily B) were recombinantly produced and the purified proteins were characterized using diverse cellulose and chitin substrates. The purified PcaLOOLs weakened cellulose filter paper and cellulose nanofibril networks (CNF); however, none significantly boosted cellulase activity on the selected cellulose substrates (Avicel and Whatman paper). Although fusing the family 63 carbohydrate-binding module (CBM63) of BsEXLX1 encoded by Bacillus subtilis to PcaLOOLs increased their binding to cellulose, the CBM63 fusion appeared to reduce the cellulose filter paper weakening observed using wild-type proteins. Binding of PcaLOOLs to alpha-chitin was considerably higher than that to cellulose (Avicel) and was pH dependent, with the highest binding at pH 5.0. Amendment of certain PcaLOOLs in fungal liquid cultivations also impacted the density of the cultivated mycelia. The present study reveals the potential of fungal expansin-related proteins to impact both cellulose and chitin networks and points to a possible biological role in fungal cell wall processing. IMPORTANCE The present study deepens investigations of microbial expansin-related proteins and their applied significance by (i) reporting a detailed comparison of diverse loosenins encoded by the same organism, (ii) considering both cellulosic and chitin-containing materials as targeted substrates, and (iii) investigating the impact of the C-terminal carbohydrate binding module (CBM) present in other expansin-related proteins on loosenin function. By revealing the potential of fungal loosenins to impact both cellulose and chitin-containing networks, our study reveals a possible biological and applied role of loosenins in fungal cell wall processing.


Assuntos
Celulose , Phanerochaete , Celulose/metabolismo , Quitina , Phanerochaete/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
17.
Crit Rev Food Sci Nutr ; 63(24): 6983-7015, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35213281

RESUMO

Natural bioactive compounds (BCs) are types of chemicals found in plants and certain foods that promote good health, however they are sensitive to processing and environmental conditions. Microencapsulation by spray drying is a widely used and cost-effective approach to create a coating layer to surround and protect BCs and control their release, enabling the production of high functional products/ingredients with extended shelf life. In this process, wall materials determine protection efficiency, and physical properties, bioavailability, and storage stability of microencapsulated products. Therefore, an understanding of physicochemical properties of wall materials is essential for the successful and effective spray-dried microencapsulation process. Typically, polysaccharide-based wall materials are generated from more sustainable sources and have a wider range of physicochemical properties and applications compared to their protein-based counterparts. In this review, we highlight the essential physicochemical properties of polysaccharide-based wall materials for spray-dried microencapsulation of BCs including solubility, thermal stability, and emulsifying properties, rheological and film forming properties. We provide further insight into possibilities for the chemical structure modification of native wall materials and their controlled release behaviors. Finally, we summarize the most recent studies involving polysaccharide biopolymers as wall materials and/or emulsifiers in spray-dried microencapsulation of BCs.


Assuntos
Extratos Vegetais , Polissacarídeos , Polissacarídeos/química , Extratos Vegetais/química , Alimentos , Solubilidade
19.
Int J Nanomedicine ; 17: 4321-4337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147546

RESUMO

Purpose: Silver nanoparticles (AgNPs) have shown great potential as anticancer agents, namely in therapies' resistant forms of cancer. The progression of prostate cancer (PCa) to resistant forms of the disease (castration-resistant PCa, CRPC) is associated with poor prognosis and life quality, with current limited therapeutic options. CRPC is characterized by a high glucose consumption, which poses as an opportunity to direct AgNPs to these cancer cells. Thus, this study explores the effect of glucose functionalization of AgNPs in PCa and CRPC cell lines (LNCaP, Du-145 and PC-3). Methods: AgNPs were synthesized, further functionalized, and their physical and chemical composition was characterized both in water and in culture medium, through UV-visible spectrum, dynamic light scattering (DLS), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). Their effect was assessed in the cell lines regarding AgNPs' entering pathway, cellular proliferation capacity, ROS production, mitochondrial membrane depolarization, cell cycle analysis and apoptosis evaluation. Results: AgNPs displayed an average size of 61nm and moderate monodispersity with a slight increase after functionalization, and a round shape. These characteristics remained stable when redispersed in culture medium. Both AgNPs and G-AgNPs were cytotoxic only to CRPC cells and not to hormone-sensitive ones and their effect was higher after functionalization showing the potential of glucose to favor AgNPs' uptake by cancer cells. Entering through endocytosis and being encapsulated in lysosomes, the NPs increased the ROS, inducing mitochondrial damage, and arresting cell cycle in S Phase, therefore blocking proliferation, and inducing apoptosis. Conclusion: The nanoparticles synthesized in the present study revealed good characteristics and stability for administration to cancer cells. Their uptake through endocytosis leads to promising cytotoxic effects towards CRPC cells, revealing the potential of G-AgNPs as a future therapeutic approach to improve the management of patients with PCa resistant to hormone therapy or metastatic disease.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Neoplasias de Próstata Resistentes à Castração , Antineoplásicos/química , Antineoplásicos/farmacologia , Glucose , Hormônios , Humanos , Masculino , Nanopartículas Metálicas/química , Extratos Vegetais/química , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Espécies Reativas de Oxigênio , Prata/química , Prata/farmacologia , Água
20.
Carbohydr Polym ; 292: 119660, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725206

RESUMO

Xylan is a biopolymer readily available from forest resources. Various modification methods, including oxidation with sodium periodate, have been shown to facilitate the engineering applications of xylan. However, modification procedures are often optimized for semicrystalline high molecular weight polysaccharide cellulose rather than for lower molecular weight and amorphous polysaccharide xylan. This paper elucidates the procedure for the periodate oxidation of xylan into dialdehyde xylan and its further reduction into a dialcohol form and is focused on the modification work up. The oxidation-reduction reaction decreased the molecular weight of xylan while increased the dispersity more than 50%. Unlike the unmodified xylan, all the modified grades could be solubilized in water, which we see essential for facilitating the future engineering applications of xylan. The selection of quenching and purification procedures and pH-adjustment of the reduction step had no significant effect on the degree of oxidation, molecular weight and only a minor effect on the hydrodynamic radius in water. Hence, it is possible to choose the simplest oxidation-reduction route without time consuming purification steps within the sequence.


Assuntos
Polissacarídeos , Xilanos , Celulose , Oxirredução , Polissacarídeos/química , Água/química , Xilanos/química
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