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1.
Mol Biol Rep ; 51(1): 950, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39222158

RESUMEN

BACKGROUND: Hepatic fibrosis, a prevalent chronic liver condition, involves excessive extracellular matrix production associated with aberrant wound healing. Hepatic stellate cells (HSCs) play a pivotal role in liver fibrosis, activated by inflammatory factors such as sphingosine 1-phosphate (S1P). Despite S1P's involvement in fibrosis, its specific role and downstream pathway in HSCs remain controversial. METHODS: In this study, we investigated the regulatory role of S1P/S1P receptor (S1PR) in Hippo-YAP activation in both LX-2 cell lines and primary HSCs. Real-time PCR, western blot, pharmacological inhibitors, siRNAs, and Rho activity assays were adopted to address the molecular mechanisms of S1P mediated YAP activation. RESULTS: Serum and exogenous S1P significantly increased the expression of YAP target genes in HSCs. Pharmacologic inhibitors and siRNA-mediated knockdowns of S1P receptors showed S1P receptor 2 (S1PR2) as the primary mediator for S1P-induced CTGF expression in HSCs. Results using siRNA-mediated knockdown, Verteporfin, and Phospho-Tag immunoblots showed that S1P-S1PR2 signaling effectively suppressed the Hippo kinases cascade, thereby activating YAP. Furthermore, S1P increased RhoA activities in cells and ROCK inhibitors effectively blocked CTGF induction. Cytoskeletal-perturbing reagents were shown to greatly modulate CTGF induction, suggesting the important role of actin cytoskeleton in S1P-induced YAP activation. Exogeneous S1P treatment was enough to increase the expression of COL1A1 and α-SMA, that were blocked by YAP specific inhibitor. CONCLUSIONS: Our data demonstrate that S1P/S1PR2-Src-RhoA-ROCK axis leads to Hippo-YAP activation, resulting in the up-regulation of CTGF, COL1A1 and α-SMA expression in HSCs. Therefore, S1PR2 may represent a potential therapeutic target for hepatic fibrosis.


Asunto(s)
Factor de Crecimiento del Tejido Conjuntivo , Células Estrelladas Hepáticas , Lisofosfolípidos , Transducción de Señal , Esfingosina , Factores de Transcripción , Proteínas Señalizadoras YAP , Quinasas Asociadas a rho , Proteína de Unión al GTP rhoA , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/efectos de los fármacos , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/genética , Lisofosfolípidos/metabolismo , Lisofosfolípidos/farmacología , Humanos , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/genética , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Proteínas Señalizadoras YAP/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Receptores de Esfingosina-1-Fosfato/metabolismo , Receptores de Esfingosina-1-Fosfato/genética , Línea Celular , Cirrosis Hepática/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Familia-src Quinasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Receptores de Lisoesfingolípidos/metabolismo , Receptores de Lisoesfingolípidos/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Vía de Señalización Hippo
2.
Curr Microbiol ; 81(10): 310, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39152363

RESUMEN

A Gram-stain-negative, strictly aerobic, non-motile, rod-shaped, designated strain CAU 1642 T, was isolated from a Salicornia herbacea collected from a tidal flat in the Yellow Sea. Strain CAU 1642 T grew optimally at pH 8.0 and 30 °C. The highest 16S rRNA gene sequence similarity was 97.25%, with Pseudomarinomonas arenosa CAU 1598 T, and phylogenetic analysis indicated that strain CAU 1642 T belongs to the genus Pseudomarinomonas. The major cellular fatty acids were iso-C15:0, iso-C16:0, and summed feature 9 (iso-C17:1ω9c and/or 10-methyl C16:0). Ubiquinone-8 was the major respiratory quinone. The draft genome of strain CAU 1642 T was 4.5 Mb, with 68.7 mol% of G + C content. The phylogenetic, phenotypic, and chemotaxonomic analysis data reveal strain CAU 1642 T to be of a novel genus in the family Lysobacteraceae, with the proposed name Pseudomarinomonas salicorniae sp. nov. with type strain CAU 1642 T (= KCTC 92084 T = MCCC 1K07085T).


Asunto(s)
Composición de Base , Chenopodiaceae , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S , Chenopodiaceae/microbiología , ARN Ribosómico 16S/genética , Ácidos Grasos/análisis , Ácidos Grasos/química , ADN Bacteriano/genética , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Quinonas/análisis , Ubiquinona/química , Ubiquinona/análogos & derivados , Genoma Bacteriano
3.
Gut Pathog ; 16(1): 44, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187879

RESUMEN

BACKGROUND: While significant research exists on gut microbiota changes after anti-tumor necrosis factor-alpha (anti TNF-α) therapy for ulcerative colitis, little is known about the longitudinal changes related to the effects of anti TNF-α. This study aimed to investigate the dynamics of gut microbiome changes during anti TNF-α (adalimumab) therapy in patients with ulcerative colitis (UC). RESULTS: The microbiota composition was affected by the disease severity and extent in patients with UC. Regardless of clinical remission status at each time point, patients with UC exhibited microbial community distinctions from healthy controls. Distinct amplicon sequence variants (ASVs) differences were identified throughout the course of Adalimumab (ADA) treatment at each time point. A notable reduction in gut microbiome dissimilarity was observed only in remitters. Remitters demonstrated a decrease in the relative abundances of Burkholderia-Caballeronia-Paraburkholderia and Staphylococcus as the treatment progressed. Additionally, there was an observed increase in the relative abundances of Bifidobacterium and Dorea. Given the distribution of the 48 ASVs with high or low relative abundances in the pre-treatment samples according to clinical remission at week 8, a clinical remission at week 8 with a sensitivity and specificity of 72.4% and 84.3%, respectively, was predicted on the receiver operating characteristic curve (area under the curve, 0.851). CONCLUSIONS: The gut microbiota undergoes diverse changes according to the treatment response during ADA treatment. These changes provide insights into predicting treatment responses to ADA and offer new therapeutic targets for UC.

4.
Carbohydr Polym ; 342: 122411, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048203

RESUMEN

We propose a closed-loop pretreatment process, wherein volatiles produced during steam explosion pretreatment were recovered and reintroduced as acid catalysts into the pretreatment system. The volatiles were separated through a drastic decompression process followed by a steam explosion process and recovered as a liquified catalyst (LFC) through a heat exchanger. The LFC effectively served as an acid catalyst for hemicellulose hydrolysis, significantly decreasing residence time from 90 min to 30 min to achieve 80 % conversion yield at 170 °C. Hydrolysates with high content of lower molecular weight oligomeric sugars were obtained using LFC, and were considered advantageous for application as prebiotics. These results are attributed to the complementary features of acetic acid and furfural contained within the LFC. Computational simulation using Aspen Plus was used to investigate the effects of recycling on LFC, and it demonstrated the feasibility of the catalyst-recirculating system. A validation study was conducted based on simulation results to predict the actual performance of the proposed pretreatment system. Based on these results, the recirculating system was predicted to improve the conversion yield and low-molecular weight oligomers yield by 1.5-fold and 1.6-fold, respectively.


Asunto(s)
Avena , Glucuronatos , Oligosacáridos , Vapor , Catálisis , Hidrólisis , Oligosacáridos/química , Avena/química , Glucuronatos/química , Polisacáridos/química
5.
Artículo en Inglés | MEDLINE | ID: mdl-38995165

RESUMEN

A Gram-negative, non-motile, and creamy-white coloured bacterium, designated CAU 1616T, was isolated from sea sand collected at Ayajin Beach, Goseong-gun, Republic of Korea. The bacterium was found to grow optimally at 37 °C, pH 8.0-8.5, and with 1-5 % (w/v) NaCl. Phylogenetic analyses based on the 16S rRNA gene sequences placed strain CAU 1616T within the order Rhodospirillales. The highest 16S rRNA gene sequence similarity was to Fodinicurvata fenggangensis YIM D812T (94.1 %), Fodinicurvata sediminis YIM D82T (93.7 %), Fodinicurvata halophila BA45ALT (93.6 %) and Algihabitans albus HHTR 118T (92.3 %). Comparing strain CAU 1616T with closely related species (Fodinicurvata fenggangensis YIM D812T and Fodinicurvata sediminis YIM D82T), the average nucleotide identity based on blast+ values were 69.7-69.8 %, the average amino acid identity values were 61.3-61.4 %, and the digital DNA-DNA hybridization values were 18.4-18.5 %. The assembled draft genome of strain CAU 1616T had 29 contigs with an N50 value of 385.8 kbp, a total length of 3 490 371 bp, and a DNA G+C content of 65.1 mol%. The predominant cellular fatty acids were C18 : 1 2-OH, C19 : 0 cyclo ω8c, and summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c). The major respiratory quinone was Q-10. Based on phenotypic, phylogenetic, and chemotaxonomic evidence, strain CAU 1616T represents a novel genus in the family Rhodovibrionaceae, for which the name Aquibaculum arenosum gen. nov., sp. nov. is proposed. The type strain is CAU 1616T (=KCTC 82428T=MCCC 1K06089T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S , Arena , Análisis de Secuencia de ADN , ARN Ribosómico 16S/genética , Ácidos Grasos/química , ADN Bacteriano/genética , República de Corea , Arena/microbiología , Agua de Mar/microbiología , Ubiquinona
6.
Artículo en Inglés | MEDLINE | ID: mdl-38779765

RESUMEN

LncRNA PRR34-AS1 overexpression promotes the proliferation and invasion of hepatocellular carcinoma (HCC) cells, but whether it affects HCC energy metabolism remains unclear. Mitochondrial division and glycolytic reprogramming play important roles in tumor development. In this study, the differential expression of PRR34-AS1 is explored via TCGA analysis, and higher levels of PRR34-AS1 are detected in patients with liver cancer than in healthy individuals. A series of experiments, such as CCK-8, PCR, and immunofluorescence staining, reveal that the proliferation, invasion, glycolysis, and mitochondrial division of PRR34-AS1-overexpressing hepatoma cells are significantly promoted. TCGA analysis and immunohistochemistry reveal high expression of the mitochondrial dynamin MIEF2 in liver cancer tissues. Dual-luciferase reporter assays confirm that miR-498 targets and binds to mitochondrial elongation factor 2 (MIEF2). In addition, we show that PRR34-AS1 can sponge miR-498. Therefore, we further investigate the effects of the lncRNA PRR34-AS1/miR-498/MIEF2 axis on the growth, glucose metabolism, and mitochondrial division in hepatocellular carcinoma cells. A series of experiments are performed on hepatocellular carcinoma cells after different treatments. The results show that the proliferative activity, invasive ability, and glycolytic level of hepatocellular carcinoma cells are decreased in HCC cells with low PRR34-AS1 expression, and the miR-498 expression level is increased in these cells. Inhibition of miR-498 or overexpression of MIEF2 restored the proliferative activity, invasive ability, glycolysis, and mitochondrial division in hepatocellular carcinoma cells. Thus, PRR34-AS1 regulates MIEF2 by sponging miR-498, thereby promoting mitochondrial division, mediating glycolytic reprogramming and ultimately driving the growth and invasion of HCC cells. Furthermore, in vivo mouse experiments yield results similar to those of the in vitro experiments, verifying the above results.

7.
Curr Microbiol ; 81(6): 150, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647555

RESUMEN

A Gram-stain-negative, aerobic, rod-shaped, motile, flagellated bacterial strain, designated as CAU 1639T, was isolated from the tidal flat sediment on the Yellow Sea in the Republic of Korea. Growth of the isolate was observed at 20-37 °C, at pH 5.0-10.5 and with 0-7% (w/v) NaCl. The genomic DNA G + C content was 60.8%. Phylogenetic analysis, grounded on 16S rRNA gene sequencing, revealed that strain CAU 1639T was closely related to species within the genus Roseibium. It shared the highest similarity with Roseibium album CECT 5095T, followed by Roseibium aggregatum IAM 12614T and Roseibium salinum Cs25T, with 16S rRNA gene sequence similarity ranging from 98.0-98.4%. It was observed that the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values ranged between 72.5-79.5 and 20.0-22.9%, respectively. The polyphasic taxonomic analysis reveals that strain CAU 1639T represents a novel species in the genus Roseibium with the proposed name Roseibium sediminicola sp. nov. The type strain is CAU 1639T (= KCTC 82430T = MCCC 1K06081T).


Asunto(s)
Composición de Base , ADN Bacteriano , Sedimentos Geológicos , Filogenia , ARN Ribosómico 16S , Agua de Mar , Sedimentos Geológicos/microbiología , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , República de Corea , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Rhodobacteraceae/clasificación , Rhodobacteraceae/genética , Rhodobacteraceae/aislamiento & purificación , Análisis de Secuencia de ADN , Hibridación de Ácido Nucleico , Ácidos Grasos/análisis , Ácidos Grasos/química , ADN Ribosómico/genética
8.
ACS Omega ; 9(8): 9432-9442, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38434861

RESUMEN

In this study, production and isolation of glucaric acid from lignocellulosic biomass were performed via potassium cation-based TEMPO-mediated oxidation for the ease of glucaric acid isolation. To optimize the oxidation conditions, response surface methodology (RSM) was adopted using standard glucose as the raw material. Among the oxidation conditions, the dosage of oxidant and pH of reaction affected the glucaric acid production, and the optimum conditions were suggested by RSM analysis: 5 °C of reaction temperature, 4.23 equiv dosage of KClO per mole of glucose, and pH of 12. Furthermore, glucaric acid was produced from lignocellulosic biomass-derived enzymatic hydrolysate from Miscanthus under optimum conditions. The impurities such as xylose and lignin in enzymatic hydrolysate inhibited the efficiency of glucose oxidation. As a result, more oxidant was required to produce sufficient glucaric acid from the enzymatic hydrolysate compared to standard glucose. The produced glucaric acid was simply isolated by controlling the pH in the form of glucaric acid monopotassium salt, which showed lower solubility in water, and the purity of isolated glucaric acid was over 99%. The overall mass balance of feedstock to glucaric acid was analyzed, suggesting that 86.38% (w/w) glucaric acid could be produced from initial glucan in feedstock.

9.
Carbohydr Polym ; 334: 122036, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38553234

RESUMEN

Nanocellulose, owing to its environmentally friendly and unique attributes, is gaining traction in various industries. However, commercialization of nanocellulose faces challenges due to structural alterations during drying process, leading to irreversible aggregation. This study, inspired by wood's natural structure, introduces a cellulose nanofibril (CNF) drying system using hemicellulose hydrolysate (HH) as a capping agent. The addition of only 1 wt% of HH to the CNF suspension not only prevents aggregation among CNFs during dehydration and drying but also dramatically enhances the redispersion rate and dispersion stability of the dried CNFs. The redispersed CNF/HH suspension exhibits physicochemical properties comparable to the original CNF suspension before drying. This confirms that HH inhibits irreversible hydrogen bonding among CNFs, leading to the restoration of the nanostructure during redispersion. Moreover, HH in the CNF suspension after redispersion can be easily removed through a simple water rinsing process, highlighting HH as a highly suitable candidate for preventing aggregation of CNFs.

10.
J Med Virol ; 96(2): e29477, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38376942

RESUMEN

Human parechovirus A (HPeV-A) is a causative agent of respiratory and gastrointestinal illnesses, acute flaccid paralysis encephalitis, meningitis, and neonatal sepsis. To clarify the characteristics of HPeV-A infection in children, 391 fecal specimens were collected from January 2014 to October 2015 from patients with acute gastroenteritis in Seoul, South Korea. Of these, 221/391 (56.5%) HPeV-A positive samples were found in children less than 2 years old. Three HPeV-A genotypes HPeV-A1 (117/221; 52.94%), HPeV-A3 (100/221; 45.25%), and HPeV-A6 (4/221; 1.81%) were detected, among which HPeV-A3 was predominant with the highest recorded value of 58.6% in 2015. Moreover, recombination events in the Korean HPeV-A3 strains were detected. Phylogenetic analysis revealed that the capsid-encoding regions and noncapsid gene 2A of the four Korean HPeV-A3 strains are closely related to the HPeV-A3 strains isolated in Canada in 2007 (Can82853-01), Japan in 2008 (A308/99), and Taiwan in 2011 (TW-03067-2011) while noncapsid genes P2 (2B-2C) and P3 (3A-3D) are closely related to those of HPeV-A1 strains BNI-788St (Germany in 2008) and TW-71594-2010 (Taiwan in 2010). This first report on the whole-genome analysis of HPeV-A3 in Korea provides insight into the evolving status and pathogenesis of HPeVs in children.


Asunto(s)
Parechovirus , Niño , Recién Nacido , Humanos , Preescolar , Filogenia , Parechovirus/genética , República de Corea/epidemiología , Evolución Biológica , Recombinación Genética
11.
J Microbiol Biotechnol ; 34(4): 911-919, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38379292

RESUMEN

Solar UVB irradiation cause skin photoaging by inducing the high expression of matrix metalloproteinase (MMPs) to inhibit the expression of Type1 procollagen synthesis. 1-Kestose, a natural trisaccharide, has been indicated to show a cytoprotective role in UVB radiation-induced-HaCaT cells. However, few studies have confirmed the anti-aging effects. In the present study, we evaluated the anti-photoaging and pathological mechanism of 1-kestose using Human keratinocytes (HaCaT) cells. The results found that 1-kestose pretreatment remarkably reduced UVB-generated reactive oxygen species (ROS) accumulation in HaCaT cells. 1-Kestose suppressed UVB radiation-induced MMPs expressions by blocking MAPK/AP-1 and NF-κB p65 translocation. 1-Kestose pretreatment increased Type 1 procollagen gene expression levels by activating TGF-ß/Smad signaling pathway. Taken together, our results demonstrate that 1-kestose may serve as a potent natural trisaccharide for inflammation and photoaging prevention.


Asunto(s)
Colágeno Tipo I , Transducción de Señal , Envejecimiento de la Piel , Trisacáridos , Rayos Ultravioleta , Humanos , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Células HaCaT , Inflamación/metabolismo , Queratinocitos/metabolismo , Queratinocitos/efectos de los fármacos , Metaloproteinasas de la Matriz/metabolismo , Metaloproteinasas de la Matriz/genética , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Piel/metabolismo , Piel/efectos de los fármacos , Piel/efectos de la radiación , Envejecimiento de la Piel/efectos de los fármacos , Envejecimiento de la Piel/efectos de la radiación , Proteínas Smad/metabolismo , Factor de Transcripción AP-1/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Rayos Ultravioleta/efectos adversos , Trisacáridos/farmacología
12.
Curr Microbiol ; 81(3): 73, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38253726

RESUMEN

A Gram-staining-positive, aerobic, non-spore-forming bacterium was isolated from coastal sand samples from Incheon in the Republic of Korea and designated as strain CAU 1645T. The optimum conditions for growth were observed at 30 °C in growth media containing 1% (w/v) NaCl at pH 9.0. The predominant respiratory quinone was MK-9 and the major fatty acids were C16:0, C17:1 w7c, and summed feature 7. Similarly, the 16S rRNA gene sequence exhibited the highest similarity with Mycolicibacterium bacteremicum DSM 45578T and Mycolicibacterium neoaurum JCM 6365T, both of which exhibited similarity rates of 97.2%. The genomic DNA G+C content was 68.2%. The whole genome of strain CAU 1645T was obtained and annotated with annotation using RAST server. The pan-genome analysis was determined using Prokka, Roary, and Phandango. In the pan-genome analysis, the strain CAU 1645T shared 40 core genes with closely related Mycolicibacterium species, including the AcpM gene, the meromycolate extension acyl carrier protein involved in forming impermeable cell walls in mycobacteria. Therefore, our findings demonstrated that the isolate represents a novel species of the genus Mycolicibacterium, for which we propose the name Mycolicibacterium arenosum sp. nov. The type strain is CAU 1645T (= KCTC 49724T = MCCC 1K07087T).


Asunto(s)
Proteína Transportadora de Acilo , Arena , ARN Ribosómico 16S/genética , Pared Celular , Medios de Cultivo
13.
Int J Biol Macromol ; 257(Pt 2): 128810, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38101680

RESUMEN

In this study, a lignin-based hydrogel for wastewater treatment was prepared by incorporating kraft lignin (KL) into a poly (vinyl alcohol) (PVA) matrix. The underwater structural stability of the KL-PVA hydrogel was guaranteed through physicochemical crosslinking, involving freeze-thaw process and chemical crosslinking reaction. The KL-PVA hydrogel displayed superior compressive characteristics compared to the original PVA hydrogel. This improvement was attributed to the chemical crosslinking and the reinforcing effect of the incorporated KL microparticles. The incorporation of anionic KL microparticles into the PVA three-dimensional network structure enhanced the cationic methylene blue (MB) and crystal violet (CV) adsorption efficiency of the prepared KL-PVA hydrogel. The MB adsorption results were well explained by pseudo-2nd order kinetics model and Langmuir isotherm model. Electrostatic forces, hydrogen bonding and π-π stacking interactions were the main adsorption mechanisms between cationic dyes and KL surfaces, indicating the potential of KL-PVA hydrogel as an effective adsorption material. Moreover, regulating the molecular weight of PVA not only prevented lignin leakage from the KL-PVA hydrogel but also elevated the KL content within the hydrogel, consequently improving its dye removal performance. For KL-PVA hydrogel with high molecular weight PVA, the MB and CV adsorption capacities were 193.8 mg/g and 190.0 mg/g, respectively.


Asunto(s)
Hidrogeles , Contaminantes Químicos del Agua , Hidrogeles/química , Lignina/química , Colorantes/química , Concentración de Iones de Hidrógeno , Cloruro de Polivinilo , Adsorción , Cinética , Azul de Metileno/química , Cationes , Contaminantes Químicos del Agua/química
14.
Int J Biol Macromol ; 253(Pt 6): 127293, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37806424

RESUMEN

In this study, the intrinsic brittleness of poly(lactic acid) (PLA) was overcome by chemical modification using ethyl acetate-extracted lignin (EL) via cationic ring-opening polymerization (CROP). The CROP was conducted to promote homopolymerization under starvation of the initiator (oxyrane). This method resulted in the formation of lignin-based polyether (LPE). LPE exhibited enhanced interfacial compatibility with nonpolar and hydrophobic PLA owing to the fewer hydrophilic hydroxyl groups and a long polyether chain. In addition, because of the UV-protecting and radical-scavenging abilities of lignin, LPE/PLA exhibited multifunctional properties, resulting in improved chemical properties compared with the neat PLA film. Notably, one of the LPE/PLA films (EL_MCF) exhibited excellent elongation at break of 297.7 % and toughness of 39.92 MJ/m3. Furthermore, the EL_MCF film showed superior UV-protective properties of 99.52 % in UVA and 88.95 % in UVB ranges, both significantly higher than those of the PLA film, without sacrificing significant transparency in 515 nm. In addition, the radical scavenging activity improved after adding LPE to the PLA film. These results suggest that LPEs can be used as plasticizing additives in LPE/PLA composite films, offering improved physicochemical properties.


Asunto(s)
Lignina , Poliésteres , Lignina/química , Polimerizacion , Poliésteres/química
15.
Int J Biol Macromol ; 253(Pt 7): 127472, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37858649

RESUMEN

Acetylated lignin (AL) can improve compatibility with commercial plastic polymers compared to existing lignin and can be used as an effective additive for eco-friendly biocomposites. For this reason, AL can be effectively incorporated into polylactic acid (PLA)-based biocomposites, but its biodegradation properties have not been investigated. In this study, biodegradation experiments were performed under mesophilic and thermophilic conditions to determine the effect of AL addition on the biodegradation characteristics of PLA-based biocomposites. As a result, the PLA-based biocomposite showed a faster biodegradation rate in a thermophilic composting environment, which is higher than the glass transition temperature of PLA, compared to a mesophilic environment. 16S rDNA sequencing results showed that differences in microbial communities depending on mesophilic and thermophilic environments strongly affected the biodegradation rate of lignin/PLA biocomposites. Importantly, the addition of AL can effectively delay the thermophilic biodegradation of PLA biocomposites. As a result of tracking the changes in physicochemical properties according to the biodegradation period in a thermophilic composting environment, the main biodegradation mechanism of AL/PLA biocomposite hydrolysis. It proceeded with cleavage of the PLA molecular chain, preferential biodegradation of the amorphous region, and additional biodegradation of the crystalline region. Above all, adding AL can be proposed as an effective additive because it can minimize the decline in the mechanical properties of PLA and delay the biodegradation rate more effectively compared to existing kraft lignin (KL).


Asunto(s)
Compostaje , Lignina , Lignina/química , Poliésteres/química , Temperatura
16.
Invest Ophthalmol Vis Sci ; 64(12): 30, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721740

RESUMEN

Purpose: We hypothesized that antioxidative enzymes supplementation could be a treatment option for dry eye. We investigated the efficacy of oral administration of Bacillus-derived superoxide dismutase (Bd-SOD) in a murine experimental dry eye (EDE). Methods: In part I, mice were randomly assigned to normal control, EDE, and mice groups that were treated with oral Bd-SOD after induction of EDE (EDE + Bd-SOD group; four mice in each group). Expression of SOD2, a major antioxidant enzyme with manganese as a cofactor, was assessed by immunofluorescence staining. In part II, mice were divided into seven groups (six mice in each group): normal control, EDE, vehicle-treated, topical 0.05% cyclosporin A (CsA)-treated, and oral Bd-SOD-treated (2.5, 5.0, and 10.0 mg/kg Bd-SOD) groups. Tear volume, tear-film break-up time (TBUT), and corneal fluorescein-staining scores (CFS) were measured at zero, five, and 10 days after treatment. Ten days after treatment, 2',7'-dichlorodihydrofluorescein diacetate for reactive oxygen species (ROS), enzyme-linked immunosorbent for malondialdehyde, and TUNEL assays for corneal apoptosis, flow cytometry inflammatory T cells, and histological assessment were performed. Results: Compared to the normal control group in part I, the EDE group showed significantly decreased SOD2 expression by immunofluorescence staining. However, the EDE + Bd-SOD group recovered similar to the normal control group. In part II, ROS, malondialdehyde, and corneal apoptosis were decreased in CsA and all Bd-SOD-treated groups. Corneal and conjunctival inflammatory T cells decreased, and conjunctival goblet cell density increased in CsA-treated and Bd-SOD-treated groups. Compared to the CsA-treated group, the 2.5 mg/kg Bd-SOD-treated group showed increased TBUT and decreased inflammatory T cells, and the 5.0 mg/kg Bd-SOD-treated group showed decreased CFS and increased conjunctival goblet cells. Conclusions: Oral Bd-SOD administration might increase autogenous SOD2 expression in ocular surface tissue in EDE and could be developed as a complementary treatment for DE in the future.


Asunto(s)
Bacillus , Síndromes de Ojo Seco , Animales , Ratones , Especies Reactivas de Oxígeno , Superóxido Dismutasa , Estrés Oxidativo , Antioxidantes , Síndromes de Ojo Seco/tratamiento farmacológico , Apoptosis , Ciclosporina
17.
Int J Biol Macromol ; 245: 125545, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37355075

RESUMEN

Ecofriendly multifunctional films with only biomass-based components have gathered significant interest from researchers as next-generation materials. Following this trend, a TEMPO-oxidized cellulose nanofibril (TOCNF) film containing hydrophilic lignin (CL) was fabricated. To produce the lignin, peracetic acid oxidation was carried out, leading to the introduction of carboxyl groups into the lignin structure. By adding hydrophilic lignin, various characteristics (e.g., surface smoothness, UV protection, antimicrobial activity, and barrier properties) of the TOCNF film were enhanced. In particular, the shrinkage of CNF was successfully prevented by the addition of CL, which is attributed to the lower surface roughness (Ra) from 18.93 nm to 4.99 nm. As a result, the smooth surface of the TOCNF/CL film was shown compared to neat TOCNF film and TOCNF/Kraft lignin composite film. In addition, the TOCNF/CL film showed a superior UV blocking ability of 99.9 % with high transparency of 78.4 %, which is higher than that of CNF-lignin composite films in other research. Also, water vapor transmission rate was reduced after adding CL to TOCNF film. Consequently, the developed TOCNF/CL film can be potentially utilized in various applications, such as food packaging.


Asunto(s)
Celulosa Oxidada , Nanofibras , Celulosa/química , Lignina/química , Nanofibras/química , Vapor
18.
Artículo en Inglés | MEDLINE | ID: mdl-37252862

RESUMEN

A Gram-stain-negative, aerobic, rod-shaped bacterium, designated as strain CAU 1638T, was isolated from seaweed sediment collected in the Republic of Korea. The cells of strain CAU 1638T grew at 25-37 °C (optimum, 30 °C), at pH 6.0-7.0 (optimum, pH 6.5) and in the presence of 0-10% NaCl (optimum, 2 %). The cells were positive for catalase and oxidase and did not hydrolyse starch and casein. Strain CAU 1638T was most closely related to Gracilimonas amylolytica KCTC 52885T (97.7 %), followed by Gracilimonas halophila KCTC 52042T (97.4 %), Gracilimonas rosea KCCM 90206T (97.2 %), Gracilimonas tropica KCCM 90063T and Gracilimonas mengyeensis DSM 21985T (97.1 %), as revealed by 16S rRNA gene sequencing. MK-7 was the major isoprenoid quinone, and iso-C15  : 0 and C15  : 1 ω6c were the major fatty acids. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, two unidentified lipids, two unidentified glycolipids and three unidentified phospholipids. The G+C content of the genome was 44.2 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain CAU 1638T and the reference strains were 73.1-73.9 % and 18.9-21.5  %, respectively. Based on its phylogenetic, phenotypic and chemotaxonomic features, strain CAU 1638T represents a novel species of the genus Gracilimonas, for which the name Gracilimonas sediminicola sp. nov. is proposed. The type strain is CAU 1638T (=KCTC 82454T=MCCC 1K06087T).


Asunto(s)
Ácidos Grasos , Flavobacteriaceae , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Fosfolípidos/química , República de Corea
19.
FEMS Microbiol Lett ; 3702023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-37248047

RESUMEN

A Gram-negative, non-motile, and reddish-orange colored bacterium, designated CAU 1643T, was isolated from a mudflat collected in Ganghwa Island, Republic of Korea. The bacterium was found to grow optimally at 30°C, pH 9.0-9.5, and with 0%-1% (w/v) NaCl. The highest 16S rRNA gene sequence similarities to the bacterium were Algoriphagus kandeliae XY-J91T (97.9%), A. aquimaris F21T (97.1%), A. formosus XAY3209T (97.0%), and A. marincola DSM 16067T (96.2%). The DNA G + C content of the type strain was 40.35 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain CAU 1643T and the reference strains were below the threshold value for species demarcation. The predominant cellular fatty acids were iso-C15:0, iso-C17:0 3-OH, and Summed Feature 9. The major respiratory quinone was menaquinone-7. The genome showed three putative biosynthetic gene clusters that are responsible for different secondary metabolites. Moreover, CAU 1643T contains 72 genes that encode carbohydrate-active enzymes. Based on phenotypic, phylogenetic, and chemotaxonomic evidence, strain CAU 1643T represents novel species in the genus Algoriphagus, for which the name A. limi sp. nov. is proposed. The type strain is CAU 1643T ( = KCTC 92080T, = MCCC 1K07150T).


Asunto(s)
Bacteroidetes , Agua de Mar , Agua de Mar/microbiología , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Genómica
20.
Therap Adv Gastroenterol ; 16: 17562848231168199, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37153496

RESUMEN

Background: Therapeutic targets for ulcerative colitis (UC) and prediction models of antitumor necrosis factor (TNF) therapy outcomes have not been fully reported. Objective: Investigate the characteristic metabolite and lipid profiles of fecal samples of UC patients before and after adalimumab treatment and develop a prediction model of clinical remission following adalimumab treatment. Design: Prospective, observational, multicenter study was conducted on moderate-to-severe UC patients (n = 116). Methods: Fecal samples were collected from UC patients at 8 and 56 weeks of adalimumab treatment and from healthy controls (HC, n = 37). Clinical remission was assessed using the Mayo score. Metabolomic and lipidomic analyses were performed using gas chromatography mass spectrometry and nano electrospray ionization mass spectrometry, respectively. Orthogonal partial least squares discriminant analysis was performed to establish a remission prediction model. Results: Fecal metabolites in UC patients markedly differed from those in HC at baseline and were changed similarly to those in HC during treatment; however, lipid profiles did not show these patterns. After treatment, the fecal characteristics of remitters (RM) were closer to those of HC than to those of non-remitters (NRM). At 8 and 56 weeks, amino acid levels in RM were lower than those in NRM and similar to those in HC. After 56 weeks, levels of 3-hydroxybutyrate, lysine, and phenethylamine decreased, and dodecanoate level increased in RM similarly to those in HC. The prediction model of long-term remission in male patients based on lipid biomarkers showed a higher performance than clinical markers. Conclusion: Fecal metabolites in UC patients markedly differ from those in HC, and the levels in RM are changed similarly to those in HC after anti-TNF therapy. Moreover, 3-hydroxybutyrate, lysine, phenethylamine, and dodecanoate are suggested as potential therapeutic targets for UC. A prediction model of long-term remission based on lipid biomarkers may help implement personalized treatment.

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