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1.
Artigo em Inglês | MEDLINE | ID: mdl-38863240

RESUMO

The initial assumption that viewed inclusion bodies as a hindrance to the efficient production of protein is no longer held due to the emergence of catalytically active inclusion bodies (CatIBs). Recent studies revealed their potential to be used in free form or immobilized as biocatalysts. The curiosity to acquire suitable catalysts has remained the measure of concern for researchers and industrialists. Numerous processes and production in various sectors of food industries, petroleum, pharmaceutical, cosmetics, and many others are still searching for a robust catalyst with outstanding features such as recyclability, resistance to pH, as well as temperature. CatIBs are forms of inclusion bodies that possess catalytic activity, which can improve catalysis efficiency, stability, and recyclability. One of the advantages of CatIBs is their potential to be used as catalysts for numerous bioprocesses when generated by an enzyme. These aggregates can efficiently be used as a replacement for traditional enzyme immobilization. This review tends to focus on the possibility of its application in various processes. The novelty of this review is that it considered the production of CatIBs both from artificial and natural perspectives, as well as how to improve it. Inclusion bodies' immobilization may provide an efficient alternative in the area of biocatalysis, and hence it will improve industrial sectors and substantially provide a means of achieving excellent performance in the near future.

2.
Environ Pollut ; 356: 124253, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851378

RESUMO

Bioaugmentation techniques still show drawbacks in the cleanup of total petroleum hydrocarbons (TPHs) from petroleum-contaminated site soil. Herein, this study explored high-performance immobilized bacterial pellets (IBPs) embed Microbacterium oxydans with a high degrading capacity, and developed a controlled-release oxygen composite (CROC) that allows the efficient, long-term release of oxygen. Tests with four different microcosm incubations were performed to assess the effects of IBPs and CROC on the removal of TPHs from petroleum-contaminated site soil. The results showed that the addition of IBPs and/or CROC could significantly promote the remediation of TPHs in soil. A CROC only played a significant role in the degradation of TPHs in deep soil. The combined application of IBPs and CROC had the best effect on the remediation of deep soil, and the removal rate of TPHs reached 70%, which was much higher than that of nature attenuation (13.2%) and IBPs (43.0%) or CROC (31.9%) alone. In particular, the CROC could better promote the degradation of heavy distillate hydrocarbons (HFAs) in deep soil, and the degradation rates of HFAs increased from 6.6% to 33.2%-21.0% and 67.9%, respectively. In addition, the IBPs and CROC significantly enhanced the activity of dehydrogenase, catalase, and lipase in soil. Results of the enzyme activity were the same as that of TPH degradation. The combined application of IBPs and CROC not only increased the microbial abundance and diversity of soil, but also significantly enhanced the enrichment of potential TPH-biodegrading bacteria. M. oxydans was dominant in AP (bioaugmentation with addition of IBPs) and APO (bioaugmentation with the addition of IBPs and CROC) microcosms that added IBPs. Overall, the IBPs and CROC developed in this study provide a novel option for the combination of bioaugmentation and biostimulation for remediating organic pollutants in soil.

3.
J Biotechnol ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852680

RESUMO

Zr-MOFs was applied for the immobilization of hyperthermophilic and halophilic amino acid dehydrogenase (Zr-MOFs-NTAaDH) by physical adsorption for the biosynthesis of L-homophenylalanine. Activity of Zr-MOFs-NTAaDH was enhanced by 3.3-fold of the free enzyme at 70°C. And the enzyme activity of Zr-MOFs-NTAaDH was maintained at 4.16 U/mg at pH 11, which was 7.8 folds of that of NTAaDH. Kinetic parameters indicated catalytic efficiency of Zr-MOFs-NTAaDH was increased compared to the free enzyme as kcat of Zr-MOFs-NTAaDH was 12.3-fold of that of free enzyme. After 7 recycles, the activity of Zr-MOFs-NTAaDH remained 68%. And Zr-MOFs-NTAaDH exhibited high ionic liquid tolerance which indicated the great potential for industrial application.

4.
J Hand Microsurg ; 16(1): 100009, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38854387

RESUMO

Background: While initial nonoperative management is the conventional approach for superficial triangular fibrocartilage complex (TFCC) tears, a substantial portion of these cases go on to require surgery, and the optimal duration of nonoperative treatment is unknown. In this study, we evaluate the cost-effectiveness of early versus late arthroscopic debridement for the treatment of superficial TFCC tears without distal radioulnar joint (DRUJ) instability. Methods: We created a decision tree to compare the following strategies from a healthcare payer perspective: immediate arthroscopic debridement versus immobilization for 4 or 6 weeks with late debridement as needed. Costs were obtained from the Centers for Medicaid and Medicare Services and a national administrative claims database. Probabilities and health-related quality-of-life measures were obtained from published sources. We conducted sensitivity analyses on model inputs, including a probabilistic sensitivity analysis consisting of 10,000 Monte Carlo simulations. Results: Immobilization for 6 weeks while reserving arthroscopic debridement for refractory cases was both the least costly and most effective strategy. Immediate arthroscopic debridement became cost-effective when success rates of immobilization for 4 or 6 weeks were less than 7.7 or 10.5%, respectively. Our probabilistic sensitivity analysis showed that immobilization for 6 weeks was preferred 97.6% of the time, and immobilization for 4 weeks was preferred 2.4% of the time. Conclusion: Although various early and late debridement strategies can be used to treat superficial TFCC tears without DRUJ instability, immobilization for 6 weeks while reserving arthroscopic debridement for refractory cases is the optimal strategy from a cost-effectiveness standpoint.

5.
J Environ Manage ; 362: 121340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38824889

RESUMO

Co-pyrolysis of biomass with phosphogypsum (PG) presents an effective strategy for facilitating the recycling of PG resources. However, it is crucial to note the environmental threats arising from the presence of Pb, Cr, Ni, and F in PG. This study investigated the effect of immobilization and transformation of four elements during co-pyrolysis with biomass and its components. The co-pyrolysis experiments were carried out in a tube furnace with a mixture of PG and corn stover (CS), cellulose (C), lignin (L), glucose (G). Co-pyrolysis occurred at varying temperatures (600 °C, 700 °C, 800 °C, and 900 °C) and different addition ratios (10%, 15%, and 20%). The results indicated that an increase in co-pyrolysis temperature was more conducive to the immobilization and transformation of harmful elements in PG, demonstrating significant efficacy in controlling F. Additionally, the addition of biomass components exerts a significant impact on inhibiting product toxicity, with small molecules such as glucose playing a prominent role in this process. The mechanism underlying the control of harmful elements during co-pyrolysis of PG and biomass was characterized by three main aspects. Firstly, biomass components have the potential to melt-encapsulate the harmful elements in PG, leading to precipitation. Secondly, the pyrolysis gas produced during the co-pyrolysis process contributes to the formation of a rich pore structure in the product. Finally, this process aids in transforming hazardous substances into less harmful forms and stabilizing these elements. The findings of this study are instrumental in optimizing the biomass and PG blend to mitigate the environmental impact of their co-pyrolysis products.


Assuntos
Biomassa , Sulfato de Cálcio , Cromo , Flúor , Chumbo , Níquel , Níquel/química , Cromo/química , Chumbo/química , Flúor/química , Sulfato de Cálcio/química , Fósforo/química , Zea mays
6.
Heliyon ; 10(11): e32223, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38873691

RESUMO

This study aimed was to covalently immobilize ß-galactosidase from Aspergillus oryzae and protease from Bacillus licheniformis on amino-functionalized multi-walled carbon nanotubes. In this study, a two-level factorial design was employed to investigate the impact of seven continuous variables (activation pH, glutaraldehyde molarity, activation time (0-8 h), buffer solution pH (8-0), buffer solution molarity, MWCNT-NH 2 -glutaraldehyde quantity, and stabilization time (0-180 h)) on the immobilization efficiency and enzymatic activity of protease and ß-galactosidase. Furthermore, the effect of time on the percentage of enzymatic activity was examined during specific intervals (24, 48, 72, 96, and 120 h) of the immobilization process. The analysis of variance results for protease enzymatic activity revealed a notable influence of the seven variables on immobilization efficiency and enzymatic activity. Additionally, the findings indicate that activation time, buffer pH, MWCNT-NH 2 -glutaraldehyde quantity, and stabilization time significantly affect the activity of the protease enzyme. The interplay between buffer pH and stabilization time is also significant. Indeed, both activation time and the quantity of MWCNT-NH 2 -glutaraldehyde exert a reducing effect on enzyme activity. Notably, the influence of MWCNT-NH 2 -glutaraldehyde quantity is more significant (p < 0.05). In terms of beta-galactosidase enzymatic activity, the study results highlight that among the seven variables considered, only the glutaraldehyde molarity, activation time, and the interplay of activation time and the quantity of MWCNT-NH 2 -glutaraldehyde can exert a statistically significant positive impact on the enzyme's activity (p < 0.05). The combination of activation time and buffer solution molarity, as well as the interactive effect of buffer pH and MWCNT-NH2-glutaraldehyde, can lead to a significant improvement in the stabilization efficiency of the protease of carbon nanotubes. The analysis of variance results demonstrated that the efficiency of covalently immobilizing ß-galactosidase from Aspergillus oryzae on amino-functionalized multi-walled carbon nanotubes is influenced by the molarity of glutaraldehyde, buffer pH, stabilization time, and the interplay of activation time + buffer pH, buffer pH + activation time, activation time + buffer molarity, and glutaraldehyde molarity + MWCNT-NH 2 -glutaraldehyde (p < 0.05). Through the optimization and selection of optimal formulations, the obtained results indicate enzyme activities and stabilization efficiencies of 64.09 % ± 72.63 % and 65.96 % ± 71.77 % for protease and beta-galactosidase, respectively. Moreover, increasing the enzyme stabilization time resulted in a reduction of enzyme activity. Furthermore, an increase in pH, temperature, and the duration of milk storage passing through the enzyme-immobilized carbon nanotubes led to a decrease in enzyme stabilization efficiency, and lactose hydrolysis declined progressively over 8-h. Hence, the covalent immobilization of ß-galactosidase from Aspergillus oryzae and protease from Bacillus licheniformis onto amino-functionalized multi-walled carbon nanotubes is anticipated to be achievable for milk applications.

7.
J Chromatogr A ; 1729: 465057, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38857565

RESUMO

The histamine H1 receptor (H1R) plays a pivotal role in allergy initiation and undergoes the necessity of devising a high-throughput screening approach centered on H1R to screen novel ligands effectively. This study suggests a method employing styrene maleic acid (SMA) extraction and His-tag covalent bonding to immobilize H1R membrane proteins, minimizing the interference of nonspecific proteins interference while preserving native protein structure and maximizing target exposure. This approach was utilized to develop a novel material for high-throughput ligand screening and implemented in cell membrane chromatography (CMC). An H1R-His-SMALPs/CMC model was established and its chromatographic performance (selectivity, specificity and lifespan) validated, demonstrating a significant enhancement in lifespan compared to previous CMC models. Subsequently, this model facilitated high-throughput screening of H1R ligands in the compound library and preliminary activity verification of potential H1R antagonists. Identification of a novel H1R antagonist laid the foundation for further development in this area.


Assuntos
Ensaios de Triagem em Larga Escala , Maleatos , Receptores Histamínicos H1 , Ligantes , Maleatos/química , Ensaios de Triagem em Larga Escala/métodos , Receptores Histamínicos H1/química , Receptores Histamínicos H1/metabolismo , Humanos , Histidina/química , Animais , Proteínas Imobilizadas/química , Proteínas Imobilizadas/metabolismo , Células CHO , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Antagonistas dos Receptores Histamínicos H1/química , Poliestirenos/química , Cricetulus , Oligopeptídeos/química
8.
Int J Biol Macromol ; 273(Pt 1): 133115, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871108

RESUMO

Aflatoxin B1 (AFB1) contamination of oils is a serious concern for the safety of edible oil consumers. Enzyme-assisted detoxification of AFB1 is an efficient and safe method for decontaminating oils, but pristine enzymes are unstable in oils and require modifications before use. Therefore, we designed a novel and magnetically separable laccase-carrying biocatalyst containing spent-mushroom-substrate (SMS)-derived biochar (BF). Laccase was immobilized on NH2-activated magnetic biochar (BF-NH2) through covalent crosslinking, which provided physicochemical stability to the immobilized enzyme. After 30 days of storage at 4 °C, the immobilized laccase (product named "BF-NH2-Lac") retained ~95 % of its initial activity, while after five repeated cycles of ABTS oxidation, ~85 % activity retention was observed. BF-NH2-Lac was investigated for the oxidative degradation of AFB1, which exhibited superior performance compared to free laccase. Among many tested natural compounds as mediators, p-coumaric acid proved the most efficient in activating laccase for AFB1 degradation. BF-NH2-Lac demonstrated >90 % removal of AFB1 within 5.0 h, while the observed degradation efficiency in corn oil and buffer was comparable. An insight into the adsorptive and degradative removal of AFB1 revealed that AFB1 removal was governed mainly by degradation. The coexistence of multi-mycotoxins did not significantly affect the AFB1 degradation capability of BF-NH2-Lac. Investigation of the degradation products revealed the transformation of AFB1 into non-toxic AFQ1, while corn oil quality remained unaffected after BF-NH2-Lac treatment. Hence, this study holds practical importance for the research, knowledge-base and industrial application of newly proposed immobilized enzyme products.

9.
J Biotechnol ; 391: 72-80, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38876311

RESUMO

The lipase from Prunus dulcis almonds was inactivated under different conditions. At pH 5 and 9, enzyme stability remained similar under the different studied buffers. However, when the inactivation was performed at pH 7, there were some clear differences on enzyme stability depending on the buffer used. The enzyme was more stable in Gly than when Tris was employed for inactivation. Then, the enzyme was immobilized on methacrylate beads coated with octadecyl groups at pH 7 in the presence of Gly, Tris, phosphate and HEPES. Its activity was assayed versus triacetin and S-methyl mandelate. The biocatalyst prepared in phosphate was more active versus S-methyl mandelate, while the other ones were more active versus triacetin. The immobilized enzyme stability at pH 7 depends on the buffer used for enzyme immobilization. The buffer used in the inactivation and the substrate used determined the activity. For example, glycine was the buffer that promoted the lowest or the highest stabilities depending on the substrate used to quantify the activities.

10.
Sci Total Environ ; 944: 173928, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871308

RESUMO

Mercury (Hg) pollution in soil has grown into a severe environmental issue. Effective in situ immobilization techniques are crucially demanded. In this study, we explored the application of carboxymethyl cellulose stabilized iron sulfide nanoparticles (CMC-FeS) for in situ immobilization of Hg in soil. CMC-FeS (a CMC-to-FeS molar ratio of 0.0004) was prepared via the reaction between FeSO4 and Na2S using CMC as a stabilizer. Remedying the Hg-polluted soil using 0.03 % CMC-FeS via batch experiments effectively reduced the acid leachable Hg by 97.5 % upon equilibrium after 71 days. Column elution tests demonstrated that the addition of CMC-FeS decreased the peak Hg concentration by 89.9 % and the total Hg mass eluted by 94.9 % after 523 pore volumes. CMC-FeS immobilized Hg in soil via chemical precipitation, ion exchange, and surface complexation. After the CMC-FeS treatment, Hg was transformed from more available exchangeable, carbonate-bound, and organic material-bound forms into the less available residual fraction, reducing the environmental risk of soil Hg from medium to low. The application of CMC-FeS boosted the soil enzyme activities and enhanced the soil bacterial diversity whereas decreased the production of methylmercury. CMC-FeS also facilitated long-term immobilization of Hg in soil. The acid leachable Hg and relative Hg bioaccessibility was decreased. Lift cycle assessment indicated that the preparation and application of CMC-FeS for in situ Hg remediation in soil met green chemistry principles. The present study confirms that CMC-FeS can be applied as an efficient and "green" amending agent for long-term Hg immobilization in soil/sediment.

11.
J Biotechnol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880386

RESUMO

Protein engineering is crucial to improve enzymes' efficiency and robustness for industrial biocatalysis. NOV1 is a bacterial dioxygenase that holds biotechnological potential by catalyzing the one-step oxidation of the lignin-derived isoeugenol into vanillin, a popular flavoring agent used in food, cleaning products, cosmetics and pharmaceuticals. This study aims to enhance NOV1 activity and operational stability through the identification of distal hotspots. located at more than 9Å from the active site using Zymspot, a tool that predicts advantageous distant mutations, streamlining protein engineering. A total of 41 variants were constructed using site-directed mutagenesis and the six most active enzyme variants were then recombined. Two variants, with two and three mutations, showed nearly a 10-fold increase in activity and up to 40-fold higher operational stability than the wild-type. Furthermore, these variants show 90 to100% immobilization efficiency in metal affinity resins, compared to approximately 60% for the wild-type. In bioconversions where 50mM of isoeugenol was added stepwise over 24-hour cycles, the 1D2 variant produced approximately 144mM of vanillin after six reaction cycles, corresponding to around 22mg, indicating a 35% molar conversion yield. This output was around 2.5 times higher than that obtained using the wild-type. Our findings highlight the efficacy of distal protein engineering in enhancing enzyme functions like activity, stability, and metal binding selectivity, thereby fulfilling the criteria for industrial biocatalysts. This study provides a novel approach to enzyme optimization that could have significant implications for various biotechnological applications.

12.
J Frailty Sarcopenia Falls ; 9(2): 157-160, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835624

RESUMO

Malnutrition, inflammation, comorbid diseases, and inactivity are known causes of sarcopenia. It results in clinical consequences like fractures, falls, low quality of life, cognitive dysfunction, and mortality. Especially in the treatment of patients with prolonged immobilization syndrome, management should not only focus on functional limitations but patients should also be evaluated and followed up for sarcopenia. In this case report, we present the management of probable secondary sarcopenia in the intensive care unit as a result of urosepsis and discuss it in the light of the literature.

13.
J Hazard Mater ; 474: 134838, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850944

RESUMO

Microplastics (MPs) pose an emerging threat to soil ecological function, yet effective solutions remain limited. This study introduces a novel approach using magnetic biochar immobilized PET hydrolase (MB-LCC-FDS) to degrade soil polyethylene terephthalate microplastics (PET-MPs). MB-LCC-FDS exhibited a 1.68-fold increase in relative activity in aquatic solutions and maintained 58.5 % residual activity after five consecutive cycles. Soil microcosm experiment amended with MB-LCC-FDS observed a 29.6 % weight loss of PET-MPs, converting PET into mono(2-hydroxyethyl) terephthalate (MHET). The generated MHET can subsequently be metabolized by soil microbiota to release terephthalic acid. The introduction of MB-LCC-FDS shifted the functional composition of soil microbiota, increasing the relative abundances of Microbacteriaceae and Skermanella while reducing Arthobacter and Vicinamibacteraceae. Metagenomic analysis revealed that MB-LCC-FDS enhanced nitrogen fixation, P-uptake and transport, and organic-P mineralization in PET-MPs contaminated soil, while weakening the denitrification and nitrification. Structural equation model indicated that changes in soil total carbon and Simpson index, induced by MB-LCC-FDS, were the driving factors for soil carbon and nitrogen transformation. Overall, this study highlights the synergistic role of magnetic biochar-immobilized PET hydrolase and soil microbiota in degrading soil PET-MPs, and enhances our understanding of the microbiome and functional gene responses to PET-MPs and MB-LCC-FDS in soil systems.

14.
Int J Biol Macromol ; 273(Pt 1): 133027, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857717

RESUMO

D-allulose, a low-calorie rare sugar catalyzed by D-allulose 3-epimerase (DAE), is highly sought after for its potential health benefits. However, poor reusability and stability of DAE limited its popularization in industrial applications. Although metal-organic frameworks (MOFs) offer a promising enzyme platform for enzyme immobilization, developing customized strategies for MOF immobilization of enzymes remains challenging. In this study, we introduce a designable strategy involving the construction of bimetal-organic frameworks (ZnCo-MOF) based on metal ions compatibility. The DAE@MOFs materials were prepared and characterized, and the immobilization of DAE and the enzymatic characteristics of the MOF-immobilized DAE were subsequently evaluated. Remarkably, DAE@ZnCo-MOF exhibited superior recyclability which could maintain 95 % relative activity after 8 consecutive cycles. The storage stability is significantly improved compared to the free form, with a relative activity of 116 % remaining after 30 days. Molecular docking was also employed to investigate the interaction between DAE and the components of MOFs synthesis. The results demonstrate that the DAE@ZnCo-MOF exhibited enhanced catalytic efficiency and increased stability. This study introduces a viable and adaptable MOF-based immobilization strategy for enzymes, which holds the potential to expand the implementation of enzyme biocatalysts in a multitude of disciplines.

15.
Yakugaku Zasshi ; 144(6): 643-650, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38825473

RESUMO

Inspired by the mechanism by which microorganisms utilize siderophores to ingest iron, four different FeIII complexes of typical artificial siderophore ligands containing catecholate and/or hydroxamate groups, K3[FeIII-LC3], K2[FeIII-LC2H1], K[FeIII-LC1H2], and [FeIII-LH3], were prepared. They were modified on an Au substrate surface (Fe-L/Au) and applied as microorganism immobilization devices for fast, sensitive, selective detection of microorganisms, where H6LC3, H5LC2H1, H4LC1H2, and H3LH3 denote the tri-catecholate, biscatecholate-monohydroxamate, monocatecholate-bishydroxamate, and tri-hydroxamate type of artificial siderophores, respectively. Their adsorption properties for the several microorganisms were investigated using scanning electron microscopy (SEM), quartz crystal microbalance (QCM), and electric impedance spectroscopy (EIS) methods. The artificial siderophore-iron complexes modified on the Au substrates Fe-LC3/Au, Fe-LC2H1/Au, Fe-LC1H2/Au, and Fe-LH3/Au showed specific microorganism immobilization behavior with selectivity based on the structure of the artificial siderophores. Their specificities corresponded well with the structural characteristics of natural siderophores that microorganisms release from the cell and/or use to take up an iron. These findings suggest that release and uptake are achieved through specific interactions between the artificial siderophore-FeIII complexes and receptors on the cell surfaces of microorganisms. This study revealed that Fe-L/Au systems have specific potential to serve as effective immobilization probes of microorganisms for rapid, selective detection and identification of a variety of microorganisms.


Assuntos
Sideróforos , Ouro , Ferro , Adsorção , Células Imobilizadas , Técnicas de Microbalança de Cristal de Quartzo , Microscopia Eletrônica de Varredura , Ligantes , Catecóis , Ácidos Hidroxâmicos
16.
Anal Biochem ; 693: 115582, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825160

RESUMO

Progress has been made studying cell-cell signaling communication processes. However, due to limitations of current sensors on time and spatial resolution, the role of many extracellular analytes is still unknown. A single walled carbon nanotube (SWNT) platform was previously developed based on the avidin-biotin immobilization of SWNT to a glass substrate. The SWNT platform provides real time feedback about analyte concentration and has a high concentration of evenly distributed sensors, both of which are essential for the study of extracellular analytes. Unfortunately, this initial SWNT platform is synthesized through unsterile conditions and cannot be sterilized post-production due to the delicate nature of the sensors, making it unsuitable for in vitro work. Herein the multiple-step process for SWNT immobilization is modified and the platform's biocompatibility is assessed in terms of sterility, cytotoxicity, cell proliferation, and cell morphology through comparison with non-sensors controls. The results demonstrate the SWNT platform's sterility and lack of toxicity over 72 h. The proliferation rate and morphology profiles for cells growing on the SWNT platform are similar to those grown on tissue culture substrates. This novel nano-sensor platform preserves cell health and cell functionality over time, offering opportunities to study extracellular analytes gradients in cellular communication.

17.
Int J Biol Macromol ; 273(Pt 2): 133089, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878936

RESUMO

This review shows the endeavors performed to prepare immobilized formulations of bromelain extract, usually from pineapple, and their use in diverse applications. This extract has a potent proteolytic component that is based on thiol proteases, which differ depending on the location on the fruit. Stem and fruit are the areas where higher activity is found. The edible origin of this enzyme is one of the features that determines the applications of the immobilized bromelain to a more significant degree. The enzyme has been immobilized on a wide diversity of supports via different strategies (covalent bonds, ion exchange), and also forming ex novo solids (nanoflowers, CLEAs, trapping in alginate beads, etc.). The use of preexisting nanoparticles as immobilization supports is relevant, as this facilitates one of the main applications of the immobilized enzyme, in therapeutic applications (as wound dressing and healing components, antibacterial or anticancer, mucus mobility control, etc.). A curiosity is the immobilization of this enzyme on spores of probiotic microorganisms via adsorption, in order to have a perfect in vivo compatibility. Other outstanding applications of the immobilized enzyme are in the stabilization of wine versus haze during storage, mainly when immobilized on chitosan. Curiously, the immobilized bromelain has been scarcely applied in the production of bioactive peptides.

18.
Int J Biol Macromol ; 273(Pt 2): 132928, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897510

RESUMO

Immobilized enzymes are one of the most common tools used in enzyme engineering, as they can substantially reduce the cost of enzyme isolation and use. However, efficient catalysis of solid substrates using immobilized enzymes is challenging, hydrolysis of insoluble cellulose by immobilized cellulases is a typical example of this problem. In this study, inspired by bees and honeycombs, we prepared gelatin-modified cellulase (BEE) and gelatin hydrogels (HONEYCOMB) to achieve reversible recycling versus release of cellulase through temperature-responsive changes in the triple-stranded helix-like interactions between BEE and HONEYCOMB. At elevated temperatures, BEE was released from HONEYCOMB and participated in hydrolytic saccharification. After 24 h, the glucose yields of both the free enzyme and BEE reached the same level. When the temperature was decreased, BEE recombined with HONEYCOMB to facilitate the effective separation and recycling of BEE from the system. The enzymatic system retained >70 % activity after four reuse cycles. In addition, this system showed good biocompatibility and environmental safety. This method increases the mass transfer capacity and enables easy recovery of immobilized cellulase, thereby serving as a valuable strategy for the immobilization of other enzymes.

19.
Bull Exp Biol Med ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888650

RESUMO

We studied the effect of separate and combined influence of chronic forced physical activity reduction and high-fat and high-carbohydrate diet containing cholesterol on some indicators of carbohydrate, lipid, and cholesterol metabolism in growing male Wistar rats. Used combination of factors simulating a sedentary lifestyle and unhealthy diet did not have a synergistic effect on the selected biomarkers. On the contrary, the effect was antagonistic: body weight and appetite decreased and insulin resistance increased. The obtained results indicate certain prospects of hypercholesterolemia model using in preclinical studies of specialized food products to optimize the diet of individuals with disorders of carbohydrate and lipid metabolism.

20.
Clin Imaging ; 113: 110223, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38889519

RESUMO

This article explores the practice of immobilization during fluoroscopy procedures for infants, discussing its advantages and disadvantages. The authors examine contrasting policies and thoughts on immobilization across different medical institutions. While some advocate for its routine use to minimize patient motion, enhance imaging quality, and decrease radiation exposure, others question its necessity and raise concerns about patient consent and parental distress. Ethical dilemmas are also discussed regarding patient autonomy and psychological impact on families. The authors advocate for a balanced approach, recognizing the utility of immobilization in certain clinical scenarios while still emphasizing patient-centered care. Ultimately, the article underscores the importance of institutional policies that prioritize both patient safety and ethical principles in pediatric radiology practices.

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