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2.
Environ Health Perspect ; 132(9): 97002, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39226184

RESUMO

BACKGROUND: Microplastics (MPs) have become a global environmental problem, emerging as contaminants with potentially alarming consequences. However, long-term exposure to polystyrene microspheres (PS-MS) and its effects on diet-induced obesity are not yet fully understood. OBJECTIVES: We aimed to investigate the effect of PS-MS exposure on high-fat diet (HFD)-induced obesity and underlying mechanisms. METHODS: In the present study, C57BL/6J mice were fed a normal diet (ND) or a HFD in the absence or presence of PS-MS via oral administration for 8 wk. Antibiotic depletion of the microbiota and fecal microbiota transplantation (FMT) were performed to assess the influence of PS-MS on intestinal microbial ecology. We performed 16S rRNA sequencing to dissect microbial discrepancies and investigated the dysbiosis-associated intestinal integrity and inflammation in serum. RESULTS: Compared with HFD mice, mice fed the HFD with PS-MS exhibited higher body weight, liver weight, metabolic dysfunction-associated steatotic liver disease (MASLD) activity scores, and mass of white adipose tissue, as well as higher blood glucose and serum lipid concentrations. Furthermore, 16S rRNA sequencing of the fecal microbiota revealed that mice fed the HFD with PS-MS had greater α-diversity and greater relative abundances of Lachnospiraceae, Oscillospiraceae, Bacteroidaceae, Akkermansiaceae, Marinifilaceae, Deferribacteres, and Desulfovibrio, but lower relative abundances of Atopobiaceae, Bifidobacterium, and Parabacteroides. Mice fed the HFD with PS-MS exhibited lower expression of MUC2 mucin and higher levels of lipopolysaccharide and inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1ß, and IL-17A] in serum. Correlation analyses revealed that differences in the microbial flora of mice exposed to PS-MS were associated with obesity. Interestingly, microbiota-depleted mice did not show the same PS-MS-associated differences in Muc2 and Tjp1 expression in the distal colon, expression of inflammatory cytokines in serum, or obesity outcomes between HFD and HFD + PS-MS. Importantly, transplantation of feces from HFD + PS-MS mice to microbiota-depleted HFD-fed mice resulted in a lower expression of mucus proteins, higher expression of inflammatory cytokines, and obesity outcomes, similar to the findings in HFD + PS-MS mice. CONCLUSIONS: Our findings provide a new gut microbiota-driven mechanism for PS-MS-induced obesity in HFD-fed mice, suggesting the need to reevaluate the adverse health effects of MPs commonly found in daily life, particularly in susceptible populations. https://doi.org/10.1289/EHP13913.


Assuntos
Dieta Hiperlipídica , Disbiose , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Microesferas , Obesidade , Poliestirenos , Animais , Disbiose/microbiologia , Camundongos , Obesidade/microbiologia , Poliestirenos/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Microplásticos/toxicidade , RNA Ribossômico 16S
3.
Sci Rep ; 14(1): 20404, 2024 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223248

RESUMO

The research introduces a novel method for creating drug-loaded hydrogel beads that target anti-aging, anti-oxidative, and anti-inflammatory effects, addressing the interconnected processes underlying various pathological conditions. The study focuses on the development of hydrogel beads containing anti-aging compounds, antioxidants, and anti-inflammatory drugs to effectively mitigate various processes. The synthesis, characterization and in vitro evaluations, and potential applications of these multifunctional hydrogel beads are discussed. A polymeric alginate-orange peel extract (1:1) hydrogel was synthesized for encapsulating fish oil. Beads prepared with variable fish oil concentrations (0.1, 0.3, and 0.5 ml) were characterized, showing no significant decrease in size i.e., 0.5 mm and a reduction in pore size from 23 to 12 µm. Encapsulation efficiency reached up to 98% within 2 min, with controlled release achieved upto 45 to 120 min with increasing oil concentration, indicating potential for sustained delivery. Fourier-transform infrared spectroscopy confirmed successful encapsulation by revealing peak shifting, interaction between constituents. In vitro degradation studies showed the hydrogel's biodegradability improved from 30 to 120 min, alongside anti-inflammatory, anti-oxidative, anti-collagenase and anti-elastase activities, cell proliferation rate enhanced after entrapping fish oil. In conclusion, the synthesized hydrogel beads are a promising drug delivery vehicle because they provide stable and effective oil encapsulation with controlled release for notable anti-aging and regenerative potential. Targeted delivery for inflammatory and oxidative stress-related illnesses is one set of potential uses. Further research may optimize this system for broader applications in drug delivery and tissue engineering.


Assuntos
Alginatos , Antioxidantes , Óleos de Peixe , Hidrogéis , Alginatos/química , Óleos de Peixe/química , Hidrogéis/química , Antioxidantes/farmacologia , Antioxidantes/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Humanos , Envelhecimento/efeitos dos fármacos , Animais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Microesferas , Camundongos
4.
Carbohydr Polym ; 344: 122541, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39218558

RESUMO

The burgeoning requirement for purified biomacromolecules in biopharmaceutical industry has amplified the exigency for advanced chromatographic separation techniques. Herein, macroporous cellulose microspheres (CCMs) with micron-sized pores are produced by a facile regulation via carbon nanotubes (CNTs). In this strategy, the incorporation of CNTs breaks the homogeneous regeneration of the cellulose, thus providing anisotropic phase force to produce macropores. The CCMs have manifested a faster mass transfer rate and more available adsorption sites owing to well-defined macropores (2.69 ± 0.57 µm) and high specific surface area (147.47 m2 g-1). Further, CCMs are functionalized by quaternary ammonium salts (GTAc-CCMs) and utilized as anion adsorbents to adsorb pancreatic kininogenase (PK). The prepared GTAc-CCMs show rapid adsorption kinetics for PK at pH 6.0, reaching 90 % equilibrium within 60 min. Also, GTAc-CCMs for PK exhibit high adsorptive capacity (632.50 mg g-1), excellent recyclability (> 80 % removal amount after 10 cycles) and selectivity especially at pH 6.0. Notably, the GTAc-CCMs have been successfully applied in a fixed-bed chromatography process, indicating their potential as an effective chromatographic medium for rapid separation of biomacromolecules.


Assuntos
Celulose , Microesferas , Nanotubos de Carbono , Nanotubos de Carbono/química , Adsorção , Celulose/química , Porosidade , Cinética , Compostos de Amônio Quaternário/química , Concentração de Íons de Hidrogênio , Separação de Fases
5.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 40: e20240019, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103243

RESUMO

OBJECTIVE: This work is aimed to Formulate, Optimize and Evaluate Gastro-Retentive Microspheres of Antidiabetic Agent by Full Factorial Design. METHODS: Microspheres were prepared using Emulsification-cross linking technique. To this HPMC-K4M and Carbopol was dissolved in 250 ml of water and allowed to swell for 24 hr at room temperature. And separately chitosan was dissolved in 3% (v/v) glacial acetic acid and this also kept for 24 h to swell or dissolve properly. After 24hr this swelled mixture was mixed under magnetic stirrer (Remi, India) at specific stirring rate for 1hr in order to find homogeneous mass of both the gum. Then slurry of chitosan also was homogenized for half an hour. The drug, Glipizide (1g) was then added to the chitosan solution and mixed homogenesously. RESULTS: The aim of the study was to formulate and evaluate microspheres, for Gastro-Retentive Microspheres of the chosen drug. The EE of microspheres was found to be 91.52%, maximum . Buoyancy property observed was 93.82% for Optimized formulation F-9, Drug release 57.34% till 8 h. The work also aims to study various parameters affecting the behaviour of microspheres in oral dosage form. CONCLUSION: Drugs with short half-life that are absorbed from the gastrointestinal tract (GIT) are eliminated rapidly from the blood flow. To avoid this, the oral SR Gastro-retentive was developed as this formulation released the drug slowly into the GIT and maintained a stable drug concentration in the serum for a longer duration of time.


Assuntos
Quitosana , Hipoglicemiantes , Microesferas , Hipoglicemiantes/administração & dosagem , Quitosana/química , Estabilidade de Medicamentos , Preparações de Ação Retardada , Animais , Ratos , Glipizida/administração & dosagem , Glipizida/farmacocinética
6.
Molecules ; 29(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39124874

RESUMO

Developing reusable and easy-to-operate biocatalysts is of significant interest in biodiesel production. Here, magnetic whole-cell catalysts constructed through immobilizing recombinant Escherichia coli cells (containing MAS1 lipase) into Fe3O4-chitosan magnetic microspheres (termed MWCC@MAS1) were used for fatty acid methyl ester (FAME) production from waste cooking oil (WCO). During the preparation process of immobilized cells, the effects of chitosan concentration and cell concentration on their activity and activity recovery were investigated. Optimal immobilization was achieved with 3% (w/v) chitosan solution and 10 mg wet cell/mL cell suspension. Magnetic immobilization endowed the whole-cell catalysts with superparamagnetism and improved their methanol tolerance, enhancing the recyclability of the biocatalysts. Additionally, we studied the effects of catalyst loading, water content, methanol content, and reaction temperature on FAME yield, optimizing these parameters using response surface methodology and Box-Behnken design. An experimental FAME yield of 89.19% was gained under the optimized conditions (3.9 wt% catalyst loading, 22.3% (v/w) water content, 23.0% (v/w) methanol content, and 32 °C) for 48 h. MWCC@MAS1 demonstrated superior recyclability compared to its whole-cell form, maintaining about 86% of its initial productivity after 10 cycles, whereas the whole-cell form lost nearly half after just five cycles. These results suggest that MWCC@MAS1 has great potential for the industrial production of biodiesel.


Assuntos
Biocombustíveis , Quitosana , Escherichia coli , Microesferas , Escherichia coli/genética , Escherichia coli/metabolismo , Quitosana/química , Células Imobilizadas/metabolismo , Óleos de Plantas/química , Lipase/metabolismo , Lipase/genética , Metanol/química , Culinária
7.
Korean J Radiol ; 25(8): 715-725, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39109500

RESUMO

OBJECTIVE: To evaluate the outcomes of drug-eluting bead transarterial chemoembolization (DEB-TACE) according to the size of the beads for the treatment of small hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This retrospective study included 212 patients with a single HCC ≤5 cm from five tertiary institutions. One hundred and nine patients were treated with 70-150-µm doxorubicin DEBs (group A), and 103 patients received 100-300-µm doxorubicin DEBs (group B). The initial tumor response (assessed between 3 weeks and 2 months after DEB-TACE), time to local tumor progression (TTLTP), restricted mean duration of complete response (RMDCR), rate of complications, incidence of post-embolization syndrome, and length of hospital stay were compared between the two groups. Logistic regression was used to analyze prognostic factors for initial tumor response. RESULTS: The initial objective response rates were 91.7% (100/109) and 84.5% (87/103) for groups A and B, respectively (P = 0.101). In the subgroup analysis of tumors ≤3 cm, the initial objective response rates were 94.6% (53/56) and 78.0% (39/50) for groups A and B, respectively (P = 0.012). There was no significant difference in the TTLTP (median, 23.7 months for group A vs. 19.0 months for group B; P = 0.278 [log-rank], 0.190 [multivariable Cox regression]) or RMDCR at 24 months (11.4 months vs. 8.5 months, respectively; P = 0.088). In the subgroup analysis of tumors >3-cm, the RMDCR at 24 months was significantly longer in group A than in group B (11.8 months vs. 5.7 months, P = 0.024). The incidence of mild bile duct dilatation after DEB-TACE was significantly higher in group B than in group A (5.5% [6/109] vs. 18.4% [19/103], P = 0.003). CONCLUSION: DEB-TACE using 70-150-µm microspheres demonstrated a higher initial objective response rate in ≤3-cm HCCs and a longer RMDCR at 24 months in 3.1-5-cm HCCs compared to larger DEBs (100-300-µm).


Assuntos
Antibióticos Antineoplásicos , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Doxorrubicina , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/diagnóstico por imagem , Quimioembolização Terapêutica/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doxorrubicina/administração & dosagem , Resultado do Tratamento , República da Coreia , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Microesferas , Adulto
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(4): 845-852, 2024 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-39170016

RESUMO

Objective: To design and prepare a high efficiency bilirubin adsorbent with good mechanical properties and biocompatibility. Methods: In this study, quaternary ammonium pyridine was designed and synthesized, and then modified polyether sulfone microspheres, or PES/p(4-VP-co-N-VP)@6 microspheres, were prepared by phase conversion and electrostatic spraying. The morphology of the polymer components and the microspheres were studied by means of nuclear magnetic resonance (NMR) spectroscopy and scanning electron microscopy. The basic properties of the microspheres and their bilirubin adsorption efficiency were tested, and the adsorption mechanism was further explored. Blood cell counts and the clotting time of the microspheres were also measured. Results: The diameter of the modified polyether sulfone microspheres prepared in the study was approximately 700-800 µm. Compared with the original PES microspheres, the surface and internal structure of PES/p(4-VP-co-N-VP)@6 microspheres did not change significantly, and they also had a loose porous structure, with some micropores scattered around in addition to irregular large pores. Compared with the control group, the bilirubin removal effect of the modified microspheres was (94.91±0.73)% after static adsorption in bilirubin PBS buffer solution for 180 min, with the difference being statistically significant (P<0.0001). According to the findings for the clotting time, the activated partial thromboplastin time (APTT) of the blank plasma group, the control PES group, and the modified PES microsphere group were (27.57±1.25) s, (28.47±0.45) s, and (30.4±0.872) s, respectively, and the difference between the experimental group and the other two groups was statistically significant (P<0.01, P<0.05). There was no significant change in red blood cell and white blood cell counts. Conclusion: The microspheres prepared in the study have high efficiency in bilirubin adsorption, excellent mechanical properties and thermal stability, and good blood biocompatibility, and are expected to be used in the clinical treatment of patients with liver failure.


Assuntos
Bilirrubina , Microesferas , Polímeros , Sulfonas , Sulfonas/química , Polímeros/química , Adsorção , Bilirrubina/sangue , Humanos
9.
Int J Biol Macromol ; 277(Pt 2): 134350, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094877

RESUMO

In this study, a novel and cost-effective approach was employed to prepare an effective Pb(II) adsorbent. We synthesized highly porous CMCSB-SCB microbeads with multiple active binding sites by combining carboxymethylated chitosan Schiff base (CMCSB) and sugarcane bagasse (SCB). These microbeads were structurally and morphologically characterized using various physical, analytical, and microscopic techniques. The SEM image and N2-adsorption analysis of CMCSB-SCB revealed a highly porous structure with irregularly shaped voids and interconnected pores. The CMCSB-SCB microbeads demonstrated an impressive aqueous Pb(II) adsorption capacity, reaching a maximum of 318.21 mg/g, under identified optimal conditions: pH 4.5, 15 mg microbeads dosage, 30 min contact time, and Pb(II) initial concentration (350 mg/L). The successful adsorption of Pb(II) onto CMCSB-SCB beads was validated using FTIR, EDX, and XPS techniques. Furthermore, the experimental data fitting indicated a good agreement with the Langmuir model (R2 = 0.99633), whereas the adsorption kinetics aligned well with the pseudo-second-order model (R2 = 0.99978). The study also identified the Pb(II) adsorption mechanism by CMCSB-SCB microbeads as monolayer chemisorption.


Assuntos
Celulose , Quitosana , Chumbo , Microesferas , Saccharum , Bases de Schiff , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Quitosana/análogos & derivados , Chumbo/química , Chumbo/isolamento & purificação , Adsorção , Bases de Schiff/química , Celulose/química , Celulose/análogos & derivados , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Cinética , Saccharum/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Água/química
10.
ACS Appl Mater Interfaces ; 16(33): 43283-43301, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39106313

RESUMO

Transcatheter arterial embolization (TAE) in interventional therapy and tumor embolism therapy plays a significant role. The choice of embolic materials that have good biocompatibility is an essential component of TAE. For this study, we produced a multifunctional PVA embolization material that can simultaneously encapsulate Ag2S quantum dots (Ag2S QDs) and BaSO4 nanoparticles (BaSO4 NPs), exhibiting excellent second near-infrared window (NIR-II) fluorescence imaging and X-ray imaging, breaking through the limitations of traditional embolic microsphere X-ray imaging. To improve the therapeutic effectiveness against tumors, we doped the doxorubicin (DOX) antitumor drug into microspheres and combined it with a clotting peptide (RADA16-I) on the surface of microspheres. Thus, it not only embolizes rapidly during hemostasis but also continues to release and accelerate tumor necrosis. In addition, Ag2S/BaSO4/PVA microspheres (Ag2S/BaSO4/PVA Ms) exhibited good blood compatibility and biocompatibility, and the results of embolization experiments on renal arteries in rabbits revealed good embolic effects and bimodal imaging stability. Therefore, they could serve as a promising medication delivery embolic system and an efficient biomaterial for arterial embolization. Our research work achieves the applicability of NIR-II and X-ray dual-mode images for clinical embolization in biomedical imaging.


Assuntos
Doxorrubicina , Embolização Terapêutica , Microesferas , Pontos Quânticos , Compostos de Prata , Animais , Compostos de Prata/química , Compostos de Prata/farmacologia , Coelhos , Doxorrubicina/química , Doxorrubicina/farmacologia , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Álcool de Polivinil/química , Humanos , Camundongos , Antineoplásicos/química , Antineoplásicos/farmacologia , Oligopeptídeos/química , Linhagem Celular Tumoral
11.
Drug Dev Res ; 85(5): e22247, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39138857

RESUMO

Inflammatory diseases including rheumatoid arthritis are major health problems. Although different techniques and drugs are clinically available for the diagnosis and therapy of the disease, novel approaches regarding radiolabeled drug delivery systems are researched. Hence, in the present study, it was aimed to design, prepare, and characterize 99mTc-radiolabeled and tofacitinib citrate-encapsulated microsphere loaded poloxamer in situ gel formulations for the intra-articular treatment. Among nine different microsphere formulations, MS/TOFA-9 was chosen as the most proper one due to particle size, high encapsulation efficiency, and in vitro drug release behavior. Poloxamer 338 at a concentration of 15% was used to prepare in situ gel formulations. For intra-articular administration, microspheres were dispersed in an in situ gel containing 15% Poloxamer 338 and characterized in terms of gelation temperature, viscosity, rheological, mechanical, and spreadability properties. After the determination of the safe dose for MS/TOFA-9 and PLX-MS/TOFA-9 as 40 µL/mL in the cell culture study performed on healthy cells, the high anti-inflammatory effects were due to significant cellular inhibition of fibroblasts. In the radiolabeling studies with 99mTc, the optimum radiolabeling condition was determined as 200 ppm SnCl2 and 0.5 mg ascorbic acid, and both 99mTc-MS/TOFA-9 and 99mTc-PLX-MS/TOFA-9 exhibited high cellular binding capacity. In conclusion, although further in vivo experiments are required, PLX-MS/TOFA-9 was found to be a promising agent for intra-articular injection in rheumatoid arthritis.


Assuntos
Artrite Reumatoide , Quitosana , Géis , Microesferas , Piperidinas , Pirimidinas , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/diagnóstico por imagem , Pirimidinas/química , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Piperidinas/química , Piperidinas/administração & dosagem , Piperidinas/farmacocinética , Quitosana/química , Humanos , Tecnécio/química , Injeções Intra-Articulares , Pirróis/química , Pirróis/administração & dosagem , Animais , Poloxâmero/química , Tamanho da Partícula , Liberação Controlada de Fármacos
12.
Bull Environ Contam Toxicol ; 113(2): 24, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126490

RESUMO

Microplastics merit attention as they can be ingested by lower trophic organisms, transferred to the food web, and pose potential risks to higher trophic levels. This study investigated the accumulation and effects of polyethylene microbeads (PEMBs, 63-75 µm) on adult water flea Moina macrocopa (600-800 µm), an order-magnitude difference in size, as a result of acute exposure. The organisms were exposed to PEMBs in four treatments of 0 (the Control), 5, 50, and 500 mg PEMB/L for examining PEMB accumulation, survival and reproduction of the organisms after the 24- and 48-h exposures. In general, M. macrocopa ingested PEMBs within 24-h exposure and reached the cumulative PEMB accumulation value of 0.17 ± 0.21 beads/adult after 48-h exposure in the 500 mg PEMB/L treatment. Exposure to PEMBs resulted in a statistically significant decrease of the cumulative survival rates, from 93 ± 12% in the Control to 37 ± 21% in the 500 mg/L treatment. Nevertheless, exposure to PEMBs did not significantly reduce the cumulative reproduction (p > 0.05), although a decrease was observed. This study suggests that the relatively large-size PEMBs could be ingested by the relatively small-size M. macrocopa and pose potential risks to these organisms.


Assuntos
Cladocera , Polietileno , Poluentes Químicos da Água , Animais , Cladocera/efeitos dos fármacos , Cladocera/fisiologia , Microplásticos/toxicidade , Microesferas , Polietileno/toxicidade , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
13.
J Environ Manage ; 367: 122069, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39098071

RESUMO

Studying the adsorption behavior of cationic surfactants can help to develop more effective strategies to limit their dispersion in the environment. However, there have few studies on the adsorption of cationic surfactants from the perspective of critical micelle concentration (CMC). In this study, with cetyltrimethylammonium bromide (CTAB) and octadecyl trimethylammonium bromide (OTAB) serving as the model cationic surfactants, the effect of CMC on the adsorption behavior of cationic surfactant onto the surface of sodium alginate/silica (SA/SiO2) microspheres was systematically revealed. The adsorption mechanism relative to CMC was investigated under different conditions, including surfactant concentration, pH, temperature, and adsorption time. The results suggest that at identical concentrations, the smaller the CMC value of the cationic surfactants, the greater the adsorption amount (qt). qt for CTAB and OTAB were 583.2 and 678.0 mg/g respectively, with the concentration higher than their CMC value. When the concentration was lower than the CMC value of the cationic surfactants, qt for CTAB and OTAB were 123.2 and 138.7 mg/g, respectively. The CMC value of CTAB was lower than that of OTAB under identical conditions, suggesting that the adsorption of cationic surfactants is related to their CMC. These results are beneficial for the removal of cationic surfactants by adsorption methods.


Assuntos
Cátions , Micelas , Microesferas , Dióxido de Silício , Tensoativos , Tensoativos/química , Adsorção , Dióxido de Silício/química , Cátions/química , Cetrimônio/química , Compostos de Cetrimônio/química , Alginatos/química , Concentração de Íons de Hidrogênio
14.
Methods Mol Biol ; 2835: 325-337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39105928

RESUMO

Gelatin, a protein derivative from collagen, is a versatile material with promising applications in tissue engineering. Among the various forms of gelatin scaffolds, nanofibrous gelatin microspheres (NFGMs) are attracting research efforts due to their fibrous nature and injectability. However, current methods for synthesizing nanofibrous gelatin microspheres (NFGMs) have limitations, such as wide size distributions and the use of toxic solvents. To address these challenges, the article introduces a novel approach. First, it describes the creation of a microfluidic device using readily available supplies. Subsequently, it outlines a unique process for producing monodispersed NFGMs through a combination of the microfluidic device and thermally induced phase separation (TIPS). This innovative method eliminates the need for sieving and the use of toxic solvents, making it a more ecofriendly and efficient alternative.


Assuntos
Gelatina , Microesferas , Nanofibras , Gelatina/química , Nanofibras/química , Engenharia Tecidual/métodos , Microfluídica/métodos , Microfluídica/instrumentação , Alicerces Teciduais/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
15.
Int J Biol Macromol ; 277(Pt 3): 134287, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39095274

RESUMO

Concerned about water treatment, it is of great importance to present new approaches for improving photocatalytic activity. Since photocatalysis is ubiquitous in almost all chemical manufacturing processes, the development of photocatalytic systems carries significance for our environment. In this regard, three different amounts of covalent organic frameworks decorated with titanium(IV) oxide nanoparticles (TiO2/COF hybrids) in Alginate-Carboxymethyl cellulose (Alg-CMC) blend matrix were prepared under ultrasound irradiation, which Citric acid and Calcium chloride acted as two green cross-linkages. Based on the physio-chemical analyses of these bio-nanocomposite (bio-NC) beads, the Alg-CMC blend polymer appeared to be the best candidate for a disparity of TiO2/COF hybrids. Not only did COF aid to increase the distribution of TiO2 nanoparticles, but it declined the bandgap energies. The resultant Alg-CMC/TiO2/COF (TiO2/COF = 15:6) bio-NC beads demonstrated efficient photodegradation activity towards Methyl violet (MV) under Ultraviolet light. The obtained results of scavenger studies indicated that superoxide radicals and electron agents played a major role in MV degradation. Further investigation confirmed that single oxygen addition and N-de-methylation could be two important pathways for the decomposition of MV by these bio-NC beads.


Assuntos
Alginatos , Carboximetilcelulose Sódica , Violeta Genciana , Nanocompostos , Fotólise , Titânio , Raios Ultravioleta , Titânio/química , Alginatos/química , Nanocompostos/química , Carboximetilcelulose Sódica/química , Violeta Genciana/química , Estruturas Metalorgânicas/química , Catálise , Microesferas
16.
Int J Biol Macromol ; 277(Pt 3): 134407, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39097062

RESUMO

The future deployment of biomedicine fields will require a new generation of biodegradable, biocompatible, and non-toxic hydrogels. Alginate and chitosan, naturally occurring polymers, have gained significant interest for hydrogel applications. However, integrating chitosan within alginate-based hydrogels to form microspheres with homogeneous distribution and a tailored surface charge remains challenging. Herein, we report the design and fabrication of homogeneously complexed alginate-chitosan hydrogel microspheres, demonstrating their ability to enhance the viability and liver-specific functionalities of entrapped hepatocytes. By exploring and optimizing the pH and ratio of alginate and chitosan solutions, we achieved well-controlled physicochemical properties, including the degree of sphericity, hydrophilicity, charge property, and surface roughness. Unlike traditional alginate-based hydrogel microspheres, hepatocytes entrapped in homogeneous alginate-chitosan microspheres displayed enhanced viability and liver-specific functions, including albumin secretion, urea synthesis, and cytochrome P-450 enzymatic activity. This work illustrates a potential pathway for manufacturing functionalized microspheres with tunable mechanical properties and functionalities based on biocompatible alginate and chitosan for hepatocyte applications.


Assuntos
Alginatos , Sobrevivência Celular , Quitosana , Hepatócitos , Hidrogéis , Microesferas , Quitosana/química , Alginatos/química , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/citologia , Hidrogéis/química , Sobrevivência Celular/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Células Imobilizadas/metabolismo
17.
Int J Biol Macromol ; 277(Pt 3): 134454, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39102919

RESUMO

A new guar gum hydrogel beads were fabricated by dropping method from an aqueous solution of guar gum (GG) using ammonium persulphate and polyethylene glycol as initiator and crosslinker respectively, for the adsorption of chlorpyrifos (CP) from water. The semi-crystalline nature of the synthesized beads was confirmed by FESEM analysis. The TGA studies implied that the beads were thermally stable up to 600 °C. The maximum swelling ratio of 1400 gg-1 was attained at pH 9.2 and 80 min. The evidence of a strong absorption band was found in FTIR spectrum at 584 cm-1 due to -P=S of the adsorbed pesticide CP. The maximum adsorption of CP was found to be 220.97 mgg-1. The adsorption followed pseudo second-order kinetics and Langmuir adsorption isotherm with regression coefficients 0.9998 and 0.9938 which followed the chemisorption process. It is due to the hydrolysis of CP at pH 9.2 to yield 3,5,6-trichloropyridinol which in turn reacts with the carboxylic group present in GG giving -N-C=O linkage. A -ΔG indicates that the process is spontaneous and involves chemisorption which is thermodynamically and kinetically favorable and a -ΔH value (-10.37 kJ/mol) suggests that the adsorption is exothermic.


Assuntos
Clorpirifos , Galactanos , Hidrogéis , Mananas , Praguicidas , Gomas Vegetais , Poluentes Químicos da Água , Purificação da Água , Gomas Vegetais/química , Mananas/química , Galactanos/química , Clorpirifos/química , Hidrogéis/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Cinética , Praguicidas/química , Praguicidas/isolamento & purificação , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Biodegradação Ambiental , Água/química , Microesferas , Termodinâmica
18.
Int J Biol Macromol ; 277(Pt 3): 134510, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111473

RESUMO

Photoaged skin, a consequence of UV radiation-induced collagen degradation, presents a significant challenge for skin rejuvenation. Synthetic polymer microspheres, while offering collagen regeneration potential, carry risks like granulomas. To overcome this, we developed a novel agarose-collagen composite microsphere implant for skin tissue regeneration. Fabricated using an emulsification-crosslinking method, these microspheres exhibited excellent uniformity and sphericity (with a diameter of ~38.5 µm), as well as attractive injectability. In vitro studies demonstrated their superior biocompatibility, promoting cell proliferation, adhesion, and migration. Further assessments revealed favorable biosafety and blood compatibility. In vivo experiments in photoaged mice showed that implantation of these microspheres effectively reduced wrinkles, increased skin density, and improved elasticity by stimulating fibroblast encapsulation and collagen regeneration. These findings highlight the potential of agarose-collagen microspheres in dermatological and tissue engineering applications, offering a safer alternative for skin rejuvenation.


Assuntos
Materiais Biocompatíveis , Colágeno , Microesferas , Sefarose , Envelhecimento da Pele , Pele , Sefarose/química , Animais , Colágeno/química , Camundongos , Pele/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Fibroblastos/efeitos dos fármacos , Engenharia Tecidual/métodos
19.
Bioresour Technol ; 410: 131245, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39151566

RESUMO

Enhancing the stability of biomass and ensuring a stable activity of anaerobic ammonia oxidizing bacteria are crucial for successful operation of the simultaneous partial nitrification, Anammox, and denitrification (SNAD) process. In this study, gel beads of polyvinyl alcohol/phytic acid (PVA/PA) and polyvinyl alcohol/phytic acid/Fe (PVA/PA/Fe) were prepared as innovative bio-carriers. Theoretical simulations and analyses revealed that these carriers are predominantly connected via hydrogen and borate bonds, with PVA/PA/Fe also featuring metal coordination bonds. The total nitrogen removal efficiency of reactors with PVA/PA/Fe and PVA/PA increased by 13.5 % and 9.0 %, respectively, compared to reactor without carriers. The iron-enriched PVA/PA/Fe carriers significantly improve SNAD by promoting Anammox, Feammox, and nitrate-dependent Fe2+ oxidation reactions, leading to faster nitrogen conversion and higher nitrogen removal rate than reactor without carriers and with PVA/PA. Using of PVA/PA and PVA/PA/Fe gel beads as bio-carriers offers benefits to the SNAD process, including cost-effective and low carbon requirement.


Assuntos
Desnitrificação , Géis , Ferro , Nitrificação , Nitrogênio , Álcool de Polivinil , Álcool de Polivinil/química , Ferro/química , Ferro/metabolismo , Géis/química , Oxirredução , Reatores Biológicos , Reagentes de Ligações Cruzadas/química , Microesferas
20.
Ann Lab Med ; 44(6): 518-528, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39161319

RESUMO

Background: Detecting monoclonal protein (M-protein), a hallmark of plasma cell disorders, traditionally relies on methods such as protein electrophoresis, immune-electrophoresis, and immunofixation electrophoresis (IFE). Mass spectrometry (MS)-based methods, such as matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and electrospray ionization-quadrupole time-of-flight (ESI-qTOF) MS, have emerged as sensitive methods. We explored the M-protein-detection efficacies of different MS techniques. Methods: To isolate immunoglobulin and light chain proteins, six types of beads (IgG, IgA, IgM, kappa, lambda, and mixed kappa and lambda) were used to prepare samples along with CaptureSelect nanobody affinity beads (NBs). After purification, both MALDI-TOF MS and liquid chromatography coupled with Synapt G2 ESI-qTOF high-resolution MS analysis were performed. We purified 25 normal and 25 abnormal IFE samples using NBs and MALDI-TOF MS (NB-MALDI-TOF). Results: Abnormal samples showed monoclonal peaks, whereas normal samples showed polyclonal peaks. The IgG and mixed kappa and lambda beads showed monoclonal peaks following the use of daratumumab (an IgG/kappa type of monoclonal antibody) with both MALDI-TOF and ESI-qTOF MS analysis. The limits of detection for MALDI-TOF MS and ESI-qTOF MS were established as 0.1 g/dL and 0.025 g/dL, respectively. NB-MALDI-TOF and IFE exhibited comparable sensitivity and specificity (92% and 92%, respectively). Conclusions: NBs for M-protein detection, particularly with mixed kappa-lambda beads, identified monoclonal peaks with both MALDI-TOF and ESI-qTOF analyses. Qualitative analysis using MALDI-TOF yielded results comparable with that of IFE. NB-MALDI-TOF might be used as an alternative method to replace conventional tests (such as IFE) to detect M-protein with high sensitivity.


Assuntos
Cadeias kappa de Imunoglobulina , Cadeias lambda de Imunoglobulina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Humanos , Espectrometria de Massas por Ionização por Electrospray , Proteínas do Mieloma/análise , Imunoglobulina G , Cromatografia de Afinidade/métodos , Cromatografia Líquida , Microesferas
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