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1.
Foods ; 12(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38002142

RESUMO

The typical Korean diet contains a significant quantity of doenjang owing to its unique taste and health benefits. However, the presence of anti-nutritional and toxic substances, such as biogenic amines and microbial pathogens, in doenjang has resulted in a loss of revenue and poor consumer health. The present study focused on the identification and quantification of different biogenic amines, pathogenic Bacillus cereus, and yeast counts in 36 doenjang products (designated as De-1 to De-36, 500 g each) procured from the different cottage industries situated in different parts of the Republic of Korea. The results indicated, only three samples were contaminated with B. cereus, exceeding the recommended limit (4 log CFU/g) suggested by the national standards of Korea. A total of six distinct yeasts were identified in different doenjang samples, whose comprehensive enzymatic profiling suggested the absence of harmful enzymes such as N-acetyl-ß-glucosaminidase, α-chymotrypsin, and ß-glucuronidase. The biogenic amines were detected in the range of 67.68 mg/kg to 2556.68 mg/kg and classified into six major groups based on hierarchical cluster analysis. All doenjang samples contained tryptamine, putrescine, cadaverine, histamine, and tyramine, while 94.44% were positive for spermidine and spermine. The results documented the analysis of traditional cottage industry doenjang and suggest the need for constant monitoring to ensure the safety of food for the consumer.

2.
Int J Biol Macromol ; 242(Pt 2): 124842, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182634

RESUMO

Exopolysaccharides (EPS) are produced by probiotic bacteria Lactiplantibacillus plantarum PRK7 and L. plantarum PRK11. The structure of EPS-7 and EPS-11 was characterized by Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), gas chromatography-mass spectroscopy (GCMS), and thermogravimetric analysis (TGA). Further, in in vitro studies antioxidant, emulsion, and antibiofilm activity were investigated. The FTIR spectrum confirmed the presence of polysaccharides in EPS-7 and EPS-11, with absorbance at 1654.93 and 1655.33 cm-1, respectively. H1 NMR further confirmed the presence of glucose, galactose, xylose, and mannose. Sugar derivatives in EPS-7 and EPS-11 were further confirmed with GCMS. The SEM analysis revealed that EPS-7 had a weblike structure and EPS-11 had a smooth porous layer. The result of the TGA revealed that EPS-7 and EPS-11 had greater thermal stability at 319.1 and 300.1 °C, respectively. Furthermore, EPS-7 and EPS-11 showed a good percentage of free radical scavenging in DPPH (89.77 % and 93.1 %), ABTS (57.65 % and 58.63 %), hydroxyl radical scavenging (44.46 % and 40.308 %), and reducing power assay. The emulsion activity was confirmed with edible oils such as coconut oil, sesame oil, almond oil, castor oil, and neem oil. The highest emulsion activity for EPS-7 and EPS-11 was found with coconut and castor oil. In addition, the antibiofilm activity against pathogens revealed that EPS can prevent biofilm formation. Thus, it was found that EPS-7 and EPS-11 possess good structural characteristics and their biological activity makes them ideal for applications in the food and pharmaceutical industry.


Assuntos
Antioxidantes , Polissacarídeos Bacterianos , Antioxidantes/farmacologia , Antioxidantes/química , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/química , Emulsões , Espectroscopia de Infravermelho com Transformada de Fourier , Biofilmes
3.
Plants (Basel) ; 12(4)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36840055

RESUMO

The current study analyzes the biosynthesis of silver nanoparticles using the Cassia auriculate flower extract as the reducing and stabilizing agent. The Cassia auriculate- silver nanoparticles (Ca-AgNPs) obtained are characterized by UV-Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analysis. The results of the spectral characterization have revealed that the surface Plasmon resonance band observed at 448 nm confirms the formation of AgNPs. TEM analysis of the Ca-AgNPs was a predominately spherical shape with a size assortment of 30 to 80 nm and an angular size of 50 nm. The well-analyzed Ca-AgNPs were used in various biological assays, including healthcare analysis of antimicrobial, antioxidant (DPPH), and cytotoxic investigations. Ca-AgNPs showed efficient free radical scavenging activity and showed excellent antimicrobial activity against to pathogenic strains. The occurrence of Ca-AgNPs lead to reduced Live/Dead ratio of bacteria (from 36.97 ± 1.35 to 9.43 ± 0.27) but improved the accumulation of bacterial clusters. The cytotoxicity of Ca-AgNPs was carried out by MTT assay against MCF-7 breast cancer cells and a moderate cytotoxic. The approach of flower extract-mediated synthesis is a cost-efficient, eco-friendly, and easy alternative to conventional methods of silver nanoparticle synthesis.

4.
Int J Food Microbiol ; 387: 110046, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36521240

RESUMO

Gochujang (fermented hot pepper paste) products are well known for their distinct, spicy flavor. However, frequent pack burst spoilage of gochujang products occurs during transportation and storage because of microbial aerogenesis, resulting in considerable economic losses. The present study aimed to prevent pack burst spoilage of gochujang products by supplementing them with garlic ethanol extract. A simulated pack burst experiment revealed that 42.86 % of normal gochujang products were spoiled. Garlic ethanol extract significantly inhibited the growth of Zygosaccharomyces rouxii in gochujang products, with low minimum inhibitory concentration values (12.5-25 mg/mL). Gochujang products supplemented with various concentrations (1 % and 2.5 %) of garlic ethanol extract exhibited marked inhibition of microbial growth, particularly Z. rouxii, and pack burst spoilage. Microbiome analysis revealed that the pack burst samples harbored a high abundance of Z. rouxii. Supplementation of gochujang with 1 % garlic ethanol extract drastically reduced Z. rouxii abundance and prevented pack burst. Moreover, gochujang products supplemented with 1 % garlic ethanol extract exhibited a high hedonic score in the sensory analysis. Based on the results of this study, we concluded that supplementation of gochujang products with 1 % garlic ethanol extract before packaging could be effective in preventing pack burst spoilage of gochujang.


Assuntos
Capsicum , Alho , Etanol , Antioxidantes , Suplementos Nutricionais , Extratos Vegetais
5.
Environ Res ; 216(Pt 3): 114706, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336094

RESUMO

Silver nanoparticles (AgNPs) are often used as antibacterial agents. Here, graphene-silver nanoparticles (G-Ag) and graphene-silver nanoparticles poly-vinylpyrrolidone (G-AgPVPy) were prepared by chemical reduction and in-situ polymerization of vinylpyrrolidone (VPy). The prepared G-Ag and G-AgPVPy composites were characterized using various techniques. The size of the AgNPs on the graphene surface in the prepared G-Ag and G-AgPVPy composites was measured as ∼20 nm. The graphene sheets size in the G-Ag and G-AgPVPy composites were measured as 6.0-2.0 µm and 4.0-0.10 µm, respectively, which are much smaller than graphene sheets in graphite powder (GP) (10.0-3.0 µm). The physicochemical analysis confirmed the formation of G-Ag and G-AgPVPy composites and even the distribution of AgNPs and PVPy on the graphene sheets. The synthesized composites (G-AgPVPy, G-Ag) exhibited a broad-spectrum antibacterial potential against both Gram-negative and Gram-positive bacteria. The lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were calculated as >40 µg/mL using G-Ag and GP, while G-AgPVPy showed as 10 µg/mL against Staphylococcus aureus. Among GP, G-Ag, and G-AgPVPy, G-AgPVPy disturbs the cell permeability, damages the cell walls, and causes cell death efficiently. Also, G-AgPVPy was delivered as a significant reusable antibacterial potential candidate. The MIC value (10 µg/mL) did not change up to six subsequent MIC analysis cycles.


Assuntos
Grafite , Nanopartículas Metálicas , Grafite/química , Prata/química , Nanopartículas Metálicas/química , Escherichia coli , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química
6.
Ann Card Anaesth ; 25(4): 460-465, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36254911

RESUMO

Introduction: SGLT2i is a new class of drugs used for type 2 diabetes. SGLT2i are known to cause EuKA in the perioperative period. Euglycemic ketoacidosis (EuKA) can cause life-threatening metabolic acidosis in the perioperative setting. Though the event rate of SGLT2i associated diabetic ketoacidosis in nonoperative setting is low, incidence among peri-operative patients can be very high and remains unknown. Aim: The aim of this study was to find the incidence, analyze outcome, and establish correlation between risk factors and EuKA in cardiac surgical patients on SGLT2i. Materials and Methods: This is a retrospective study analyzing 24 cardiac surgical patients who were on SGLT2i for type 2 diabetes mellitus. Data collection included age, sex, BMI, preoperative HbA1C, albumin, creatinine, type of SGLT2i and timing of stopping before surgery, insulin administration in the immediate pre-operative period; use of CPB, GI infusion and inotropes in the intraoperative period; blood ketone, duration of ventilation, hydration status and length of postoperative stay in postoperative period. Patients were diagnosed to have EuKA if any one of the serially measured postoperative ketone values was more than 0.6 mmol/L (ketone positive). The collected data were used to find an association between the risk factors and the occurrence of EuKA. Results: Of the 24 patients, 17 patients developed EuKA. (70.8.%). 10 of the 17 EuKA in our study required preoperative Insulin for diabetic control whereas none in the ketone negative patients required insulin. This was statistically significant (P = 0.019). Association of other factors to EuKA were not statistically significant. Conclusion: Though the event rate of SGLT2i associated Diabetic ketoacidosis in nonoperative setting is low, (17), the occurrence of EUKA in cardiac surgical patients on SGLT2i in our study was 70.8% (17 out of 24 patients). Patients who require insulin in addition to other oral hypoglycemic drugs for immediate preoperative glycemic control are at risk for the development of SGLT2 inhibitor-induced EuKA postoperatively. Missing the diagnosis of EuKA is fatal in these patients. We couldn't make a diagnosis in our first patient whom we lost. Since it was diagnosed in all our study patients by measuring serial ketone values, there was no mortality and insignificant morbidity. Cessation of SGLT2i before surgery, expectant watch for blood ketones, and treatment with GI infusion reduce morbidity and mortality in cardiac surgical patients.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Diabetes Mellitus Tipo 2 , Cetoacidose Diabética , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Albuminas/análise , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Creatinina , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Cetoacidose Diabética/diagnóstico , Cetoacidose Diabética/epidemiologia , Hemoglobinas Glicadas/análise , Incidência , Insulina/uso terapêutico , Cetonas/sangue , Estudos Retrospectivos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
7.
Chemosphere ; 307(Pt 4): 136061, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35977575

RESUMO

Consumption of fermented Prunus mume fruit (maesil) sugar syrup raise a health concern due to the presence of the cyanogenic glucoside amygdalin. The goal of the present study was to investigate the amygdalin degradation potential and genome profile of the native microbes found in maesil syrup. The microbial profile analysis revealed that yeast is the predominant microorganism native to maesil syrup and that the isolated yeast cells showed a remarkable potential for amygdalin reduction (99.7%). Moreover, the reduction in amygdalin was inversely proportional to the growth of the isolated yeast. The whole-genome analysis revealed that the isolated yeast is Zygosaccharomyces rouxii (genome size 10 Mb, 39.25% of GC content). Of the 5250 genes (64.88%) predicted in the Z. rouxii genome, 5245 (99.90%) were annotated using NCBI Non-Redundant, UniProt, and InterProScan databases. The genome of the isolated Z. ruoxii harbored 2.03% of repeats and 0.68% of non-coding RNAs. Protein prediction indicated that ß-glycosidases and hydroxynitrile lyase may play a key role in amygdalin degradation. The predicted degradation initiated by ß-glycosidases that hydrolyze α-glucosidic bonds of amygdalin results in α-hydroxy nitriles (cyanohydrins) that are subsequently converted into carbonyl compounds (benzaldehyde) and hydrogen cyanide catalyzed by hydroxynitrile lyases. Present findings provide valuable data for constructing engineered microorganisms that can degrade amygdalin. Further analysis of Z. rouxii may elucidate the exact mechanism of amygdalin reduction in the production of maesil syrup.


Assuntos
Amigdalina , Prunus , Amigdalina/análise , Amigdalina/química , Amigdalina/metabolismo , Benzaldeídos/análise , Frutas/química , Glucosídeos , Glicosídeo Hidrolases , Glicosídeos , Cianeto de Hidrogênio/análise , Nitrilas/química , Prunus/química , Prunus/metabolismo , Saccharomyces cerevisiae/metabolismo , Açúcares
8.
Gels ; 8(4)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35448149

RESUMO

Cellulose pulp (CP), polyurethane (PU), and curcumin-based biocompatible composite films were prepared using a simple cost-effective method. Significant structural and microstructural changes were studied using FT-IR spectroscopy, XRD, and SEM. The 5% and 10% gravimetric losses of the CP/PU/curcumin composite were found to be in the range 87.2-182.3 °C and 166.7-249.8 °C, respectively. All the composites exhibited single Tg values in the range 147.4-154.2 °C. The tensile strength of CP was measured to be 93.2 MPa, which dropped to 14.1 MPa for the 1:0.5 CP/PU composite and then steadily increased to 30.5 MPa with further addition of PU. The elongation at the break of the composites decreased from 8.1 to 3.7% with the addition of PU. The addition of PU also improved the water vapor permeability (3.96 × 10-9 to 1.75 × 10-9 g m-1 s-1 Pa-1) and swelling ratio (285 to 202%) of the CP composite films. The CP/PU/curcumin composite exhibited good antioxidant activity and no cytotoxicity when tested on the HaCat cell line. The visual appearance and UV transmittance (86.2-32.9% at 600 nm) of the CP composite films were significantly altered by the incorporation of PU and curcumin. This study demonstrates that CP/PU/curcumin composites can be used for various packaging and biomedical applications.

9.
Environ Res ; 212(Pt B): 113273, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35439456

RESUMO

Natural products derived carbon quantum dots (CQDs) catch huge attention owing to their distinctive properties of smaller size, water dispersibility, high photostability, lower cost, tunable emission, biocompatibility, least toxicity, electrical conductivity, optical and catalytic properties, and easy modification. Herein high fluorescent CQDs were prepared using Borassus flabellifer (ice apple) as a carbon source utilizing the simplistic one-step hydrothermal method. The prepared CQDs possessed excellent photoluminescence, high photostability, and stability in an aqueous solution and harbored large of quantum yield and strong stability in high pH conditions with the characteristic strong blue fluorescence emission. With these superior properties, the CQDs have been used as sensing probes for the detection of Fe3+ ions having excellent selectivity and sensitivity with a 2.01 µM limit of detection. The CQDs decorated probe was found effective in detecting Fe3+ ions in the tap and drinking mineral water, suggesting the applicability of the prepared sensor. The developed sensor exhibited advantages, including simple, low-cost, label-free, rapid, and good sensitivity and selectivity towards Fe3+ ions, with a great application for detection of such ions in real water.


Assuntos
Pontos Quânticos , Carbono/química , Endosperma , Corantes Fluorescentes/química , Íons , Pontos Quânticos/química , Água
10.
Environ Res ; 212(Pt C): 113323, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35472463

RESUMO

The present study focused on synthesizing ZnO nanoparticles (NPs) and CuO NPs using Elaeagnus indica leaf extract as reducing and stabilizing agents using Zn(O2CCH3)2 and Cu2SO4, respectively, for the first time. We have confirmed the formation of aggregated ZnO NPs and CuO NPs with phytochemicals by various spectral analyses and electron microscopy studies. The size of synthesized ZnO NPs and CuO NPs were in the range of 20-30 nm and 30-40 nm, respectively. The antimicrobial activity of ZnO NPs at 75 µg concentration is superior against Salmonella typhimurium, Klebsiella pneumonia, Bacillus subtilis, Staphylococcus epidermidis, and Aspergillus niger. While CuO nanoparticles with 75 µg concentration effectively inhibited S. typhimurium, B. subtilis, S. epidermidis, and A. niger. Phytochemicals and reactive oxygen species generated by the prepared NPs may account for the antimicrobial effects observed. The photodegradation of methylene blue by ZnO NPs and CuO NPs was 91% and 76%, respectively, for 6 h of sunlight exposure. CuO NPs and ZnO NPs have different intrinsic properties and phytochemical compositions; hence ZnO NPs photodegrade faster than CuO NPs even though ZnO has higher bandgap energy than CuO. Consequently, CuO and ZnO NPs produced from E. indica leaf extract might be utilized as antimicrobials and photocatalysts in the future.


Assuntos
Elaeagnaceae , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacologia , Biomimética , Cobre/química , Elaeagnaceae/metabolismo , Nanopartículas Metálicas/química , Nanopartículas/química , Extratos Vegetais/farmacologia , Óxido de Zinco/química
11.
Foods ; 11(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35159525

RESUMO

Gochujang, fermented red pepper paste, is a grain-based Korean traditional food. The quality of gochujang produced by cottage industries is not well-documented. Thus, the present study aimed to analyze the quality of gochujang from 35 traditional cottage industries for physicochemical and microbial characteristics, along with volatile compound contents. In addition to microbial characteristics, salinity, pH, free amino nitrogen, and alcohol content were evaluated. Ethanol was detected as the predominant alcohol and 57% of tested gochujang products harbored >1% of total alcohol content, which was above the recommended level for halal products. Gochujang products contained hexadecanoic and linoleic acids predominantly and several volatile compounds belonging to the classes of alcohols, aldehydes, alkanes, nitrogen-containing compounds, and terpenes. A wide range of aerobic mesophilic bacteria (2.79-8.73 log CFU/g) and yeast counts (1.56-7.15 log CFU/g) was observed. Five distinct yeast species were identified, including Zygosaccharomyces rouxii. Eight gochujang products were found to be contaminated with Bacillus cereus (>4 log CFU/g). This study suggests that there is a need to limit B. cereus contamination in cottage industry products and reduce alcohol content to comply with halal food guidelines.

12.
J Fungi (Basel) ; 8(2)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35205943

RESUMO

Meju, a raw material for doenjang preparation, is highly vulnerable to aflatoxin-producing fungi. The aim of this study was to evaluate the effect of a one-year fermentation on aflatoxins and aflatoxin-producing fungi in doenjang spiked with aflatoxins B1, G1, B2, and G2 and inoculated with toxigenic Aspergillus flavus. A significant reduction in aflatoxins was observed after a year of fermentation, measuring 92.58%, 100%, 98.69%, and 100% of B1, G1, B2, and G2, respectively. After a year of fermentation, 6.95 ± 3.64 µg/kg of total aflatoxin was detected, which represents a 97.88% reduction in the total aflatoxin compared with the initial value (328.83 ± 36.60 µg/kg). Several aflatoxin-degrading fungi (Aspergillus versicolor, Cladosporium subcinereum, Aspergillus ochraceus) and bacteria (Bacillus albus, Bacillus velezensis) isolated from doenjang were identified as the major contributors to the reduction of aflatoxin. Furthermore, it was observed that most of the aflatoxin contamination in doenjang occurred during the meju stage, and this stage was found to be most susceptible to A. flavus contamination and growth. These findings reveal that native microorganisms mediate aflatoxin clean-up in doenjang during fermentation and support the use of such microorganisms as a starter culture for the preparation of aflatoxin-free doenjang.

13.
Crit Rev Food Sci Nutr ; 62(20): 5395-5412, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34955062

RESUMO

Aflatoxins are carcinogenic secondary metabolites produced by Aspergillus section Flavi that contaminates a wide variety of food and feed products and is responsible for serious health and economic consequences. Fermented foods are prepared with a wide variety of substrates over a long fermentation time and are thus vulnerable to contamination by aflatoxin-producing fungi, leading to the production of aflatoxin B1. The mitigation and control of aflatoxin is currently a prime focus for developing safe aflatoxin-free food. This review summarizes the role of major aflatoxin-degrading enzymes such as laccase, peroxidase, and lactonase, and microorganisms in the context of their application in food. A putative mechanism of enzyme-mediated aflatoxin degradation and toxicity evaluation of the degraded products are also extensively discussed to evaluate the safety of degradation processes for food applications. The review also describes aflatoxin-degrading microorganisms isolated from fermented products and investigates their applicability in food as aflatoxin preventing agents. Furthermore, a summary of recent technological advancements in protein engineering, nanozymes, in silico and statistical optimization approaches are explored to improve the industrial applicability of aflatoxin-degrading enzymes.


Assuntos
Aflatoxinas , Aflatoxina B1/metabolismo , Aflatoxina B1/toxicidade , Aflatoxinas/análise , Aspergillus/metabolismo , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Fungos/metabolismo , Inativação Metabólica
14.
Foods ; 10(10)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34681419

RESUMO

Traditional gochujang is well known for its distinguished flavor and taste. However, the safety of cottage industry gochujang products is uncertain, particularly, in terms of biogenic amine (BA) content which is not yet documented. The present study aimed to determine the level of BAs present in 35 traditional gochujang products nationwide. All gochujang products had considerable amounts of total BAs ranging from 52.95 mg/kg to 176.24 mg/kg. Individually, histamine and tyramine were either not detected or detected up to 16.94 mg/kg and 2.15-52.34 mg/kg, respectively. In all the tested gochujang products, putrescine, spermidine, and spermine were detected in the range of 7.60-56.72 mg/kg, 14.96-36.93 mg/kg, and 4.68-16.31 mg/kg, respectively. A total of 22 and 19 gochujang products had less than 1 mg/kg of cadaverine and histamine, respectively. The findings indicate that all the gochujang products tested herein had BA levels below the suggested toxicity limits recommended by the various regulatory authorities, which reveal that they are safe for human consumption.

15.
Int J Biol Macromol ; 182: 1301-1309, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33989690

RESUMO

Agar/polyacrylamide/quaternary ammonium silane-based (A/P/QAS-based) composite films were developed for food and biomedical packaging applications. The structural, optical, and surface morphological properties of the A/P and A/P/QAS composites were characterized by various characterization techniques in terms of thermogravimetric analysis, differential scanning calorimetry analyses, mechanical and rheological properties. Results showed that the 5% gravimetric loss (57.8-139.1 °C), glass transition temperature (179-189.9 °C) and tensile strength (35.2-47.8 MPa) of the prepared composites increased with increasing polyacrylamide content. The contact angle and water barrier properties of the composites were considerably improved by the addition of QAS. To compare WVP values of the A/P/QAS composite with neat AP composite films it reduced nearly 46% (2.45 to 1.32 × 10-9 g/m2 Pas). The A/P/QAS composites showed excellent antimicrobial properties against five different organisms. The Staphylococcus aureus exhibited highest 25 mm for gel and 18.1 mm for film of A/P/QAS composites. All the composites exhibited shear-thinning behavior, and their viscosity increased with increasing polyacrylamide content. The storage moduli of the prepared hydrogel composites were in the range of 5000-10,600 Pa at 1 rad/s and increased continuously over the entire frequency range. The dynamic rheological properties of A/P and A/P/QAS composites indicated that the prepared composites had good mechanical strength. Biopolymer based A/P and A/P/QAS composite films are suitable for green composite packaging applications.


Assuntos
Resinas Acrílicas/química , Ágar/química , Embalagem de Alimentos , Compostos de Amônio Quaternário/química , Silanos/química , Anti-Infecciosos/farmacologia , Varredura Diferencial de Calorimetria , Módulo de Elasticidade , Testes de Sensibilidade Microbiana , Permeabilidade , Reologia , Resistência ao Cisalhamento , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Estresse Mecânico , Temperatura , Termogravimetria , Viscosidade , Difração de Raios X
16.
Cancer Immunol Immunother ; 70(3): 689-700, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32902663

RESUMO

Monophosphoryl lipid A (MPLA) is a toll-like receptor 4 ligand that promotes immune activation in mice and humans, without undesired inflammation. Immunotherapy by the combining immune checkpoint blockade and MPLA has shown promising anti-cancer effects in both mice and humans. In this study, we explored how MPLA enhanced the anti-cancer effects of anti-PD-L1 antibodies (Abs). Anti-cancer immunity induced by the combination of anti-PD-L1 Abs and MPLA failed in CD4 and CD8 cell-depleted mice. Moreover, the combination treatment of anti-PD-L1 Abs and MPLA synergistically enhanced the activation of plasmacytoid dendritic cells (pDCs) in the mouse in vivo, while conventional DCs were not. In addition, mice treated with anti-PD-L1 Abs and MPLA were not protected from B16 melanoma by blockade of interferon-alpha receptor (IFNAR). The combination of anti-PD-L1 Abs and MPLA also promoted human peripheral blood pDC activation and induced IFN-α-dependent T cell activation. Therefore, these results demonstrate that MPLA enhances anti-PD-L1 Ab-mediated anti-cancer immunity through the activation and IFN-α production of pDCs.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , Lipídeo A/análogos & derivados , Animais , Biomarcadores , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/metabolismo , Células Dendríticas/metabolismo , Feminino , Humanos , Imunofenotipagem , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Lipídeo A/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Melanoma Experimental , Camundongos
17.
Langenbecks Arch Surg ; 406(4): 1211-1221, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33174169

RESUMO

BACKGROUND: Postoperative hypocalcemia after total thyroidectomy (TT) still remains common. This prospective observation study examined the role of intraoperative time period (IOP) and intravenous fluids (IVF) in transient and permanent (> 6 months) hypocalcemia post-TT. SUBJECTS AND METHOD: Consecutive patients (n = 328; age = median (IQR); 34 (15) years; M:F = 65:263) with benign or malignant thyroid disease undergoing TT were evaluated for IOP, intraoperative IVF, serum corrected calcium, intact parathormone (iPTH), and 25-hydroxyvitamin D (25OHD) levels at baseline, 48 h, and 6 months post-TT. RESULTS: The incidence of symptomatic transient and permanent hypocalcemia post-TT was 33.5% and 7.9% respectively. In multivariate logistic regression analysis, the independent risk factors for transient hypocalcemia were IOP (odds ratio: 11.6), 48-h iPTH (4.8), IVF (2.9), hyperthyroidism (2.8), and percent calcium decline (1.07), while 25OHD deficiency increased the risk by 10.5 odds in subset with preoperative hypocalcemia. In receiver operating characteristic analysis, IOP, and IVF strongly predicted transient hypocalcemia with a threshold of 123 min and 1085 mL. Area under the curve, sensitivity, and specificity were 0.883 (95% CI: 0.838-0.928), 88.1%, and 74.4% and 0.883 (0.840-0.926; each P = 0.001), 84.4%, and 74.4% respectively. Serum 48-h calcium < 7.8 mg/dL was the only reliable predictor of permanent hypocalcemia. CONCLUSION: Operative duration > 123 min and IVF > 1085 mL increased the risk of transient hypocalcemia post-TT manyfold but not permanent hypocalcemia. Routine intraoperative identification, preservation of viable in situ parathyroid glands, and laryngeal nerves increased IOP and rates of transient hypocalcemia but improved long-term outcome.


Assuntos
Hipocalcemia , Cálcio , Pré-Escolar , Humanos , Hidrodinâmica , Hipocalcemia/epidemiologia , Hipocalcemia/etiologia , Hormônio Paratireóideo , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Tireoidectomia/efeitos adversos
18.
ACS Omega ; 5(44): 28767-28775, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33195930

RESUMO

Gellan gum-sodium carboxymethyl cellulose (GC)-based composite films with various concentrations of silicon dioxide (SiO2) nanoparticles and octadecyldimethyl-(3-triethoxy silylpropyl)ammonium chloride (ODDMAC) were successfully prepared by the traditional solution casting method to improve the antimicrobial and water repellent properties. Fourier transform infrared (FT-IR) spectra confirm the formation of hydrogen bonds between the GC and nano-SiO2. The microstructure and physicochemical properties were investigated by FT-IR, wide-angle X-ray diffraction, and scanning electron microscopy (SEM) analyses. The rheological properties of the GC-SiO2 hydrogel were also characterized. The results show that the inclusion of SiO2 nanoparticles significantly improved the viscosity and viscoelastic properties of the GC hydrogel. The GC-SiO2 hydrogel exhibited shear-thinning behavior and its viscosity decreased at high shear rates. The storage and loss moduli of the GC composites increased as the frequency and SiO2 concentration increased. The tensile strength and elongation at break of the GC composites increased by 75.9 and 62%, respectively, with the addition of SiO2 and ODDMAC. In addition, nano-SiO2 decreased the water vapor permeability and increased the hydrophobic properties of the GC-SiO2 composites. Thermogravimetric analysis showed that the T 5% loss was in the range of 99.4-128.6 °C and the char yield was in the range of 20.1-29.9%, which was significantly enhanced by the incorporation of SiO2 nanoparticles. The GC-SiO2 (ODDMAC) nanocomposites effectively shielded the UV light and exhibited high antimicrobial activity against six different pathogens. The simple and cost-effective GC-SiO2 (ODDMAC) nanocomposites gained importance in food packaging and biomedical applications.

19.
Int J Biol Macromol ; 153: 55-62, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32142841

RESUMO

Biopolymers of gellan gum (G), 2-hydroxyethyl cellulose (HEC), and lignin (L)-based binary and ternary sustainable composites were prepared for food packaging and biomedical application. The composite films were flexible and transparent or translucent with slight brown in color. The incorporation of lignin considerably improved the thermal and mechanical and hydrophobic properties of the composite films. The addition of 10 wt% of lignin to the composites increased the tensile strength by 54.3% and 59.2% respectively. The prepared lignin-based composite films showed high ultraviolet (UV) protection, with almost 100% protection against UVB (280-320 nm) and 90% against UVA (320-400 nm). The surface hydrophobicity of the composite films increased with the addition of lignin. The binary and ternary composites containing 1, 5, and 10 wt% lignin exhibited excellent radical scavenging activities. The gellan gum/HEC/lignin based composite films achieved the best biocompatibility. The obtained composites showed efficient antioxidant and non-cytotoxic activities, although there was no remarkable antimicrobial activity.


Assuntos
Antioxidantes/química , Celulose/análogos & derivados , Embalagem de Alimentos , Lignina/química , Teste de Materiais , Polissacarídeos Bacterianos/química , Raios Ultravioleta , Celulose/química , Água/química
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