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1.
Chemistry ; 30(23): e202304266, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38369590

RESUMEN

The exploration of stable, efficient, and low-cost catalysts toward ammonia borane hydrolysis is of vital significance for the practical implementation of this hydrogen production technology. Integrating interface engineering and nano-architecture engineering is a favorable strategy to elevate catalytic performance, as it can modify the electronic structure and provide sufficient active sites simultaneously. In this work, urchin-like NiCoP/CoP heterostructures are prepared via a three-step hydrothermal-oxidation-phosphorization synthesis route. It is demonstrated that the original Ni/Co molar ratio and the amount of phosphorus are crucial for adjusting the morphology, enhancing the exposed surface area, facilitating charge transfer, and modulating the adsorption and activation of H2O molecules. Consequently, the optimal Ni1Co2P heterostructure displays remarkable catalytic properties in the hydrolysis of ammonia borane with a turnover frequency (TOF) value of 30.3 molH2 ⋅ min-1 ⋅ molmetal -1, a low apparent activation energy of 25.89 kJ ⋅ mol-1, and good stability. Furthermore, by combining infrared spectroscopy and isotope kinetics experiments, a possible mechanism for the hydrolysis of ammonia borane was proposed.

2.
Environ Sci Technol ; 58(8): 3908-3918, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38329000

RESUMEN

The heterogeneous photodegradation behavior of liquid crystal monomers (LCMs) in standard dust (standard reference material, SRM 2583) and environmental dust was investigated. The measured photodegradation ratios for 23 LCMs in SRM and environmental dust in 12 h were 11.1 ± 1.8 to 23.2 ± 1.1% and 8.7 ± 0.5 to 24.0 ± 2.8%, respectively. The degradation behavior of different LCM compounds varied depending on their structural properties. A quantitative structure-activity relationship model for predicting the degradation ratio of LCMs in SRM dust was established, which revealed that the molecular descriptors related to molecular polarizability, electronegativity, and molecular mass were closely associated with LCMs' photodegradation. The photodegradation products of the LCM compound 4'-propoxy-4-biphenylcarbonitrile (PBIPHCN) in dust, including •OH oxidation, C-O bond cleavage, and ring-opening products, were identified by nontarget analysis, and the corresponding degradation pathways were suggested. Some of the identified products, such as 4'-hydroxyethoxy-4-biphenylcarbonitrile, showed predicted toxicity (with an oral rat lethal dose of 50%) comparable to that of PBIPHCN. The half-lives of the studied LCMs in SRM dust were estimated at 32.2-82.5 h by fitting an exponential decay curve to the observed photodegradation data. The photodegradation mechanisms of LCMs in dust were revealed for the first time, enhancing the understanding of LCMs' environmental behavior and risks.


Asunto(s)
Polvo , Cristales Líquidos , Animales , Ratas , Relación Estructura-Actividad Cuantitativa , Fotólisis
3.
Mar Drugs ; 22(6)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38921598

RESUMEN

To promote the bioconversion of marine chitin waste into value-added products, we expressed a novel pH-stable Micromonospora aurantiaca-derived chitinase, MaChi1, in Escherichia coli and subsequently purified, characterized, and evaluated it for its chitin-converting capacity. Our results indicated that MaChi1 is of the glycoside hydrolase (GH) family 18 with a molecular weight of approximately 57 kDa, consisting of a GH18 catalytic domain and a cellulose-binding domain. We recorded its optimal activity at pH 5.0 and 55 °C. It exhibited excellent stability in a wide pH range of 3.0-10.0. Mg2+ (5 mM), and dithiothreitol (10 mM) significantly promoted MaChi1 activity. MaChi1 exhibited broad substrate specificity and hydrolyzed chitin, chitosan, cellulose, soluble starch, and N-acetyl chitooligosaccharides with polymerization degrees ranging from three to six. Moreover, MaChi1 exhibited an endo-type cleavage pattern, and it could efficiently convert colloidal chitin into N-acetyl-D-glucosamine (GlcNAc) and (GlcNAc)2 with yields of 227.2 and 505.9 mg/g chitin, respectively. Its high chitin-degrading capacity and exceptional pH tolerance makes it a promising tool with potential applications in chitin waste treatment and bioactive oligosaccharide production.


Asunto(s)
Quitina , Quitinasas , Micromonospora , Quitinasas/metabolismo , Quitinasas/química , Quitinasas/aislamiento & purificación , Quitinasas/genética , Quitina/análogos & derivados , Quitina/metabolismo , Quitina/química , Concentración de Iones de Hidrógeno , Especificidad por Sustrato , Micromonospora/enzimología , Micromonospora/genética , Hidrólisis , Escherichia coli/genética , Quitosano/química , Estabilidad de Enzimas
4.
Environ Sci Technol ; 57(10): 4187-4198, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36848063

RESUMEN

A large-scale survey was conducted by measuring five organophosphite antioxidants (OPAs) and three novel organophosphate esters (NOPEs) in 139 dust samples across China. The median summed concentrations of OPAs and NOPEs in outdoor dust were 33.8 ng/g (range: 0.12-53,400 ng/g) and 7990 ng/g (2390-27,600 ng/g), respectively. The dust concentrations of OPAs associated with the increasing economic development and population density from western to eastern China, whereas the NOPE concentration in Northeast China (median, 11,900 ng/g; range, 4360-16,400 ng/g) was the highest. Geographically, the distribution of NOPEs was significantly associated with annual sunshine duration and precipitation at each sampling site. Results of laboratory experiments further revealed that the simulated sunlight irradiation promoted the heterogeneous phototransformation of OPAs in dust, and this process was accelerated with the existence of reactive oxygen species and enhanced relative humidity. Importantly, during this phototransformation, the hydroxylated, hydrolyzed, dealkylated, and methylated products, e.g., bis(2,4-di-tert-butylphenyl) methyl phosphate, were identified by nontargeted analysis, part of which were estimated to be more toxic than their parent compounds. The heterogeneous phototransformation pathway of OPAs was suggested accordingly. For the first time, the large-scale distribution of OPAs and NOPEs and the phototransformation of these "new chemicals" in dust were revealed.


Asunto(s)
Contaminación del Aire Interior , Retardadores de Llama , Monitoreo del Ambiente , Antioxidantes , Polvo/análisis , Ésteres/análisis , Retardadores de Llama/análisis , Organofosfatos/análisis , China , Contaminación del Aire Interior/análisis
5.
Ecotoxicol Environ Saf ; 248: 114297, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36423371

RESUMEN

The alarming increase in soil contamination by heavy metals, such as cadmium and zinc demands immediate attention. The dioecious tree Populus cathayana, a phytoremediation plant, plays an important role in rehabilitating heavy metal contaminated areas. In this study, male and female P. cathayana plants were treated with Cd (20 mg kg-1) and different levels of Zn (25, 50, or 100 mg kg-1) to study their physiological responses. The results showed that Cd exposure alone caused stress by inhibiting the growth of both male and female plants. In both males and females, photosynthesis and antioxidant enzymes activities decreased substantially under Cd stress alone. Cd was largely located in the roots, but Zn was present in the shoots of both sexes. Zn supplementation considerably increased the photosynthetic rate from 14.62 % to 60.45 % and also enhanced the antioxidant enzymes activities from 24.11 % to 86.21 %. Zn treatment decreased the translocation ability of Cd compared to the Cd-only treatment, alleviating Cd toxicity. In addition, when sufficient Zn was made available, males showed a high degree of Cd accumulation, low root-to-shoot translocation, elevated antioxidant defense abilities, and an increased photosynthetic rate, while females were less responsive to Cd stress than males. Thus, combined exposure to Cd and Zn caused differential responses in plant growth and physiological processes between males and females P. cathayana. Male plants exhibit better Cd tolerance and accumulation capacity under optimum Zn supplementation. This study increases the fundamental knowledge regarding P. cathayana plants, which can be applied to enhance their remediation capacity in Cd-contaminated soils.


Asunto(s)
Cadmio , Populus , Cadmio/toxicidad , Zinc/toxicidad , Antioxidantes , Fotosíntesis
6.
Ecotoxicol Environ Saf ; 242: 113909, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35999756

RESUMEN

Phthalates (PAEs) are widely used plasticizers drawing increasing concern due to reproductive toxicity. However, studies on serum PAEs metabolites (mPAEs) and their associations with human ovarian function remain very scarce. In this study, from April 2019 to August 2020, a total of 297 women of childbearing age were recruited in Tianjin, China. Eleven mPAEs were analyzed in serum samples and eight mPAEs were detected at frequencies > 65% with median concentrations of 0.43-15.3 ng/mL. In multinomial logistic analysis, an increase in serum mono (2-isobutyl) phthalate (miBP) was associated with decline in antral follicle count (AFC) (OR=1.26, 95% CI: 0.99, 1.61) and 5-mono-(2-ethyl-5-hydroxyhexyl) phthalate (mEHHP) was significantly associated with AFC increase (OR=1.43, 95% CI: 1.06, 1.92), which were aligned with the associations found between mPAEs and AMH through generalized linear regression. In multiple linear regression models, per 10% increase in serum mono (2-ethylhexyl) phthalate (mEHP), mono (2-ethyl-5-oxohexyl) phthalate (mEOHP) (oxo-mEHP), and principal component 1 featured for high concentrations of mono-n-butyl phthalate (mBP), miBP and mEHP were associated with 0.15 (95% CI: -0.29, -0.02), 0.01 (95% CI: -0.01, 0.00) and 0.01 (95% CI: -0.02, 0.00) ln-unit decrease in estradiol (E2) levels, respectively, while mono-[(2-carboxymethyl) hexyl] phthalate (mCMHP) (carboxymethyl-mEHP) was positively associated with 0.05 ln-unit increase of E2 (95% CI: 0.02, 0.08). The observed negative associations between mPAEs and the Anti-Müllerian hormone (AMH) also aligned with the change in AFC. Generalized linear regression also revealed nonlinear associations between mono-ethyl phthalate (mEP), mCMHP and follicle-stimulating hormone (FSH). Overall, serum mEHP and its metabolites were negatively associated with E2. miBP was negatively associated with AFC. The nonlinear associations between mPAEs and FSH, and AMH need further study.


Asunto(s)
Contaminantes Ambientales , Reserva Ovárica , Ácidos Ftálicos , Biomarcadores , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Femenino , Hormona Folículo Estimulante , Humanos , Ácidos Ftálicos/metabolismo , Plastificantes/análisis
7.
BMC Cancer ; 20(1): 1129, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-33225924

RESUMEN

BACKGROUND: The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for gallbladder carcinoma (GBC) came into force since 2018. However, the prognostic precision of this staging system has not been properly assessed. This study aimed to evaluate the latest staging system and suggest modifications to improve its prognostic precision. METHODS: Data of patients with GBC was included from the Surveillance, Epidemiology and End Results (SEER) database (2004-2015) and multicenter database (2010-2017). Baseline clinicopathologic characteristics were recorded including age, sex, race, grade, T category, N category, M category and stage. The Kaplan-Meier method was used to plot survival functions. The prediction power of the AJCC 8th edition and its modified version were evaluated using the concordance index (C-index). RESULTS: A total of 2779 GBC patients were included in the SEER database and 591 were collected from multicenter database. While no significant difference in survival of patients was observed between stages IVA and IVB using the 8th AJCC staging system (p > 0.05), the prognosis of stage IIIA showed a slightly better outcome than stage IIIB (p = 0.046) in the SEER database. In the multicenter database, there was no significant difference between stage IIIA and stage IIIB (p > 0.05). Similarly, no significant difference in the survival of patients between stages IIIA and IIIB was observed when M0 patients with at least 6 lymph nodes (LNs) were analyzed (p > 0.05) for both SEER and multicenter database. On the other hand, a modified staging system was able to stratify patients from stage IIIA, stage IIIB and stage IV (p < 0.001). For the SEER database, the C-indexes of 8th AJCC staging system and that of its modified version were 0.709 and 0.742, respectively. For the multicenter database, the C-index of 8th AJCC staging system and that of our modified version were 0.635 and 0.679, respectively. CONCLUSIONS: The modified 8th staging system proposed in this study can improve the prognostic precision of the 8th AJCC staging system for GBC. We therefore suggest including these modifications in the next update of AJCC staging system for GBC.


Asunto(s)
Neoplasias de la Vesícula Biliar/epidemiología , Femenino , Humanos , Masculino , Estadificación de Neoplasias , Pronóstico , Estados Unidos
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(3): 218-222, 2019 Mar.
Artículo en Zh | MEDLINE | ID: mdl-30907343

RESUMEN

The pertussis surveillance system has been established since 2009 in Tianjin, and continuously improved over the past 10 years. This system determines the definition and classification of pertussis, establishes simple and feasible sampling methods and laboratory detection methods in clinical practice, standardizes the report management of pertussis cases and the treatment of epidemic situations. After the implementation of the surveillance system, the number of reported pertussis cases increased from 26 in 2009 to 802 in 2017, the number of diagnosed cases increased from 19 in 2009 to 662 in 2017, the reported incidence rate of pertussis increased from 0.16/100 000 in 2009 to 4.28/100 000 in 2017, and the number of medical institutions of reporting perutssis cases increased from 2 in 2009 to 53 in 2017. The specimen collection rate of the reported cases reached up to 93.66%. These results show that the sensitivity of pertussis surveillance has been improved and show that the data from the surveillance system may reflect more precisely the epidemical characteristics of perutssis in Tianjin.


Asunto(s)
Tos Ferina , Humanos , Incidencia , Lactante , Vacuna contra la Tos Ferina
9.
Opt Express ; 23(15): 20158-75, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26367673

RESUMEN

We apply an adaptive forward error correction (FEC) allocation strategy to an Elastic Optical Network (EON) operated with shared backup path protection (SBPP). To maximize the protected network capacity that can be carried, an Integer Linear Programing (ILP) model and a spectrum window plane (SWP)-based heuristic algorithm are developed. Simulation results show that the FEC coding overhead required by the adaptive FEC scheme is significantly lower than that needed by a fixed FEC allocation strategy resulting in higher network capacity for the adaptive strategy. The adaptive FEC allocation strategy can also significantly outperform the fixed FEC allocation strategy both in terms of the spare capacity redundancy and the average FEC coding overhead needed per optical channel. The proposed heuristic algorithm is efficient and not only performs closer to the ILP model but also does much better than the shortest-path algorithm.

10.
Lancet ; 381(9881): 1916-25, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23623390

RESUMEN

BACKGROUND: Human infection with avian influenza A H7N9 virus emerged in eastern China in February, 2013, and has been associated with exposure to poultry. We report the clinical and microbiological features of patients infected with influenza A H7N9 virus and compare genomic features of the human virus with those of the virus in market poultry in Zhejiang, China. METHODS: Between March 7 and April 8, 2013, we included hospital inpatients if they had new-onset respiratory symptoms, unexplained radiographic infiltrate, and laboratory-confirmed H7N9 virus infection. We recorded histories and results of haematological, biochemical, radiological, and microbiological investigations. We took throat and sputum samples, used RT-PCR to detect M, H7, and N9 genes, and cultured samples in Madin-Darby canine kidney cells. We tested for co-infections and monitored serum concentrations of six cytokines and chemokines. We collected cloacal swabs from 86 birds from epidemiologically linked wet markets and inoculated embryonated chicken eggs with the samples. We identified and subtyped isolates by RT-PCR sequencing. RNA extraction, complementary DNA synthesis, and PCR sequencing were done for one human and one chicken isolate. We characterised and phylogenetically analysed the eight gene segments of the viruses in the patient's and the chicken's isolates, and constructed phylogenetic trees of H, N, PB2, and NS genes. FINDINGS: We identified four patients (mean age 56 years), all of whom had contact with poultry 3-8 days before disease onset. They presented with fever and rapidly progressive pneumonia that did not respond to antibiotics. Patients were leucopenic and lymphopenic, and had impaired liver or renal function, substantially increased serum cytokine or chemokine concentrations, and disseminated intravascular coagulation with disease progression. Two patients died. Sputum specimens were more likely to test positive for the H7N9 virus than were samples from throat swabs. The viral isolate from the patient was closely similar to that from an epidemiologically linked market chicken. All viral gene segments were of avian origin. The H7 of the isolated viruses was closest to that of the H7N3 virus from domestic ducks in Zhejiang, whereas the N9 was closest to that of the wild bird H7N9 virus in South Korea. We noted Gln226Leu and Gly186Val substitutions in human virus H7 (associated with increased affinity for α-2,6-linked sialic acid receptors) and the PB2 Asp701Asn mutation (associated with mammalian adaptation). Ser31Asn mutation, which is associated with adamantane resistance, was noted in viral M2. INTERPRETATION: Cross species poultry-to-person transmission of this new reassortant H7N9 virus is associated with severe pneumonia and multiorgan dysfunction in human beings. Monitoring of the viral evolution and further study of disease pathogenesis will improve disease management, epidemic control, and pandemic preparedness. FUNDING: Larry Chi-Kin Yung, National Key Program for Infectious Diseases of China.


Asunto(s)
Enfermedades Transmisibles Emergentes/virología , Genoma Viral/genética , Virus de la Influenza A/genética , Gripe Aviar/genética , Gripe Humana/virología , Zoonosis/transmisión , Animales , China , Enfermedades Transmisibles Emergentes/tratamiento farmacológico , Enfermedades Transmisibles Emergentes/transmisión , Femenino , Humanos , Virus de la Influenza A/clasificación , Gripe Aviar/transmisión , Gripe Humana/tratamiento farmacológico , Gripe Humana/transmisión , Masculino , Persona de Mediana Edad , Aves de Corral , Tomografía Computarizada por Rayos X , Zoonosis/virología
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(7): 1973-7, 2014 Jul.
Artículo en Zh | MEDLINE | ID: mdl-25269319

RESUMEN

Extraction method for dynamic spectrum (DS) with a high signal to noise ratio is a key to achieving high-precision noninvasive detection of blood components. In order to further improve the accuracy and speed of DS extraction, linear similarity between photoelectric plethysmographys (PPG) at each two different wavelengths was analyzed in principle, and an experimental verification was conducted. Based on this property, the method of compensation-fitting extraction was proposed. Firstly, the baseline of PPG at each wavelength is estimated and compensated using single-period sampling average, which would remove the effect of baseline drift caused by motion artifact. Secondly, the slope of least squares fitting between each single-wavelength PPG and full-wavelength averaged PPG is acquired to construct DS, which would significantly suppress random noise. Contrast experiments were conducted on 25 samples in NIR wave band and Vis wave band respectively. Flatness and processing time of DS using compensation-fitting extraction were compared with that using single-trial estimation. In NIR band, the average variance using compensation-fitting estimation was 69.0% of that using single-trial estimation, and in Vis band it was 57.4%, which shows that the flatness of DS is steadily improved. In NIR band, the data processing time using compensation-fitting extraction could be reduced to 10% of that using single-trial estimation, and in Vis band it was 20%, which shows that the time for data processing is significantly reduced. Experimental results show that, compared with single-trial estimation method, dynamic spectrum compensation-fitting extraction could steadily improve the signal to noise ratio of DS, significantly improve estimation quality, reduce data processing time, and simplify procedure. Therefore, this new method is expected to promote the development of noninvasive blood components measurement.


Asunto(s)
Análisis Químico de la Sangre/métodos , Espectroscopía Infrarroja Corta , Análisis de los Mínimos Cuadrados , Pletismografía , Relación Señal-Ruido
12.
Foods ; 13(15)2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39123655

RESUMEN

The purpose of this work was to construct liver-targeted nanoparticles based on the redox response to effectively deliver cannabidiol (CBD) for the prevention of acute liver injury (ALI). CBD-loaded nanoparticles (CBD NPs) with a particle size of 126.5 ± 1.56 nm were prepared using the polymer DA-PP-LA obtained by grafting pullulan polysaccharide with deoxycholic acid (DA) and α-lipoic acid (α-LA). CBD NPs showed typical redox-response release behavior. Interestingly, CBD NPs exhibited admirable liver targeting ability, significantly accumulated in the liver, and effectively promoted the internalization of CBD in liver cells, thus effectively reducing the H2O2-induced oxidative damage of HepG2 cells and avoiding apoptosis. More importantly, CBD NPs effectively prevented CCl4-induced ALI by protecting liver function, ameliorating oxidative stress levels, inhibiting the production of inflammatory factors, and protecting the liver from histological damage. This study provides a promising strategy for achieving targeted delivery of CBD NPs in the liver, thereby effectively preventing ALI.

13.
Carbohydr Res ; 540: 109144, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38733729

RESUMEN

Chitooligosaccharides, the hydrolysis products of chitin, have superior biological activities and application value to those of chitin itself; however, the ordered and highly crystalline structure of chitin renders its degradation by chitinase difficult. Herein, the effects of plasma-activated water (PAW) pre-treatment on the physicochemical properties, crystal structure, and enzymatic hydrolysis of chitin were investigated. The hydrolysis of PAW-pre-treated chitin (PAW activation time of 5 min) using chitinase from Vibrio harveyi (VhChit2) yielded 71 % more reducing sugar, compared with that from untreated chitin, with the degree of chitin hydrolysis increasing from 13 % without pre-treatment to 23 % post-treatment. Moreover, the amount of VhChit2 adsorbed by chitin increased from 41.7 to 58.2 mg/g. Fourier transform infrared spectrometry revealed that PAW could break the ß-1,4-glycosidic bonds of chitin (but had no effects on the hydrogen and amido bonds), thereby decreasing the molecular weight and crystallinity of the polysaccharide, which caused its structural damage and enhanced its enzymatic hydrolysis by chitinase. Consequently, PAW pre-treatment can be considered a simple, effective, and environmentally-friendly method for the biotransformation of chitin as its easier hydrolysis yields high-value products.


Asunto(s)
Quitina , Quitinasas , Peso Molecular , Vibrio , Agua , Quitinasas/química , Quitinasas/metabolismo , Quitina/química , Quitina/metabolismo , Quitina/análogos & derivados , Agua/química , Hidrólisis , Vibrio/enzimología
14.
Sleep ; 47(7)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38695327

RESUMEN

Although rapid eye movement (REM) sleep is conventionally treated as a unified state, it comprises two distinct microstates: phasic and tonic REM. Recent research emphasizes the importance of understanding the interplay between these microstates, hypothesizing their role in transient shifts between sensory detachment and external awareness. Previous studies primarily employed linear metrics to probe cognitive states, such as oscillatory power, while in this study, we adopt Lempel-Ziv Complexity (LZC), to examine the nonlinear features of electroencephalographic (EEG) data from the REM microstates and to gain complementary insights into neural dynamics during REM sleep. Our findings demonstrate a noteworthy reduction in LZC during phasic REM compared to tonic REM states, signifying diminished EEG complexity in the former. Additionally, we noted a negative correlation between decreased LZC and delta band power, along with a positive correlation with alpha band power. This study highlights the potential of nonlinear EEG metrics, particularly LZC, in elucidating the distinct features of REM microstates. Overall, this research contributes to advancing our understanding of the complex dynamics within REM sleep and opens new avenues for exploring its implications in both clinical and nonclinical contexts.


Asunto(s)
Electroencefalografía , Sueño REM , Humanos , Sueño REM/fisiología , Electroencefalografía/métodos , Masculino , Femenino , Adulto , Polisomnografía , Adulto Joven , Dinámicas no Lineales , Encéfalo/fisiología
15.
Mater Today Bio ; 25: 100965, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38318477

RESUMEN

The pathogenesis of ulcerative colitis (UC) is closely related to severe inflammation, damaged colonic mucosal barrier, increased oxidative stress and intestinal ecological imbalance. However, due to the nonspecific distribution and poor bioavailability of drugs, UC treatment is still a serious challenge. Here, a mitochondria/colon dual targeted nanoparticles based on redox response was developed to effectively alleviate UC. Cannabidiol nanoparticles (CBD NPs) with a particle size of 143.2 ± 3.11 nm were prepared by self-assembly using polymers (TPP-IN-LA) obtained by modifying inulin with (5-carboxypentyl) triphenyl phosphonium bromide (TPP) and α-lipoic acid (α-LA). Excitingly, the constructed CBD NPs showed excellent mitochondrial targeting, with a Pearson correlation coefficient of 0.76 at 12 h. The results of animal imaging in vivo showed that CBD NPs could be effectively accumulated in colon tissue. Not only that, CBD showed significant glutathione stimulated release in the presence of 10 mM glutathione at pH 7.4. The results of in vivo animal experiments showed that CBD NPs significantly ameliorated DSS-induced colonic inflammation by modulating the TLR4-NF-κB signaling pathway. Moreover, CBD NPs significantly improved the histological damage of colon in UC mice, increased the expression level of tight junction protein ZO-1, and effectively restored the intestinal mucosal barrier function and intestinal mucosal permeability. More importantly, CBD NPs significantly improved the species composition, abundance and amount of short chain fatty acids of intestinal flora in UC mice, thus effectively maintaining the balance of intestinal flora. The dual-targeted and glutathione-responsive nanoparticles prepared in this study provide a promising idea for achieving targeted delivery of CBD for effective treatment of UC.

16.
J Food Sci ; 89(3): 1554-1566, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38317380

RESUMEN

The Maillard reaction (MR) of tilapia byproduct protein hydrolysates was investigated for the use of byproduct protein as a food ingredient and to mask its fishy odor and bitter flavor. The flavor differences in tilapia byproduct hydrolysates before and after the MR were analyzed to explore the key flavor precursor peptides and amino acids involved in MR. The results suggested that eight key volatile substances, including 2,5-dimethylpyrazine, 2-pentylfuran, hexanal, octanal, nonanal, (E)-2-decenal, decanal, and 1-octen-3-ol contributed most to the MR products group (ROAV > 1). Ten volatile compounds, including 1-octen-3-ol, hexanal, 2-pentylfuran, 2,5-dimethylpyrazine, methyl decanoate, and 2-octylfuran, were the flavor markers that distinguished the different samples (VIP > 1). The four most consumed peptides were VAPEEHPTL, GPIGPRGPAG, KSADDIKKAF, and VWEGQNIVK. Umami peptides and bitter free amino acids (FAAs) were the key flavor precursor peptide and FAAs, respectively. Overall, the hydrolysates of tilapia byproducts with flavor improved by MR are a promising strategy for the production of flavorings.


Asunto(s)
Aldehídos , Reacción de Maillard , Octanoles , Tilapia , Animales , Cromatografía de Gases y Espectrometría de Masas , Aminoácidos , Péptidos
17.
Int Immunopharmacol ; 126: 111135, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37977065

RESUMEN

The limited efficacy of immune checkpoint inhibitors (ICIs) in the treatment of advanced Esophageal Squamous Cell Carcinoma (ESCC) poses a challenge. Recent evidence suggests that tumor cells' insensitivity to cytotoxic T lymphocytes (CTLs) contributes to drug resistance against ICIs. Here, a particular tRNA-derived fragment called tRF-3024b has been identified as playing a significant role in tumor cell resistance to CTLs. Through tRF sequencing (tRF-seq), we observed a high expression of tRF-3024b in ESCC cells that survived co-culture with CTLs. Further in vitro studies demonstrated that tRF-3024b reduced the apoptosis of tumor cells when co-cultured with CTLs. The mechanism behind this resistance involves tRF-3024b promoting the expression of B-cell lymphoma-2 (BCL-2) by sequestering miR-192-5p, a microRNA that would normally inhibit BCL-2 expression. This means that tRF-3024b indirectly enhances the protective effects of BCL-2, reducing apoptosis in tumor cells. Rescue assays confirmed that the suppressive function of tRF-3024b relies on BCL-2. In summary, the tRF-3024b/miR-192-5p/BCL-2 axis sheds light on the crucial role of tRF-3024b in regulating BCL-2 expression. These findings offer valuable insights into strategies to enhance the response of ESCC to CTLs and improve the effectiveness of immunotherapy approaches in treating ESCC.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , MicroARNs , Humanos , Carcinoma de Células Escamosas de Esófago/genética , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/genética , Linfocitos T Citotóxicos/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Movimiento Celular
18.
Food Chem ; 446: 138810, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38402769

RESUMEN

The effect of a high internal phase emulsion (HIPE) on three-dimensional-printed surimi gel inks was studied. Increasing the concentration of collagen peptide decreased the particle size of HIPE droplets and improved the viscoelasticity and stability. For example, when the collagen peptide concentration was 5 wt%, the viscoelasticity of the HIPE was high, as indicated by the presence of small and uniform particles, which formed a monolayer in the outer layer of the oil droplets to form stable a HIPE. A HIPE was used as the filling material to fill the surimi gel network, which reduced the porosity of the network. Surimi protein and peptides have dual emulsifying effects on the stabilization of oil. After adding the emulsion, the texture, gel properties and rheological properties of the surimi were reduced, and its printing adaptability was improved. This study provides new ideas for the production of surimi and its application in 3D printing.


Asunto(s)
Aceites de Pescado , Tinta , Emulsiones/química , Geles/química , Péptidos , Impresión Tridimensional , Colágeno
19.
Carbohydr Polym ; 307: 120640, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36781282

RESUMEN

In this study, two chitinases (VhChit2 and VhChit6) from Vibrio harveyi possessed specific activity of 36.5 and 20.8 U/mg, respectively. Structure analysis indicates that their amino acid composition of active sites is similar, but the substrate binding cleft of VhChit2 is deeper than that of VhChit6. They were shown to have a synergistic effect on chitin degradation, and the optimized degree of synergy and the degradation ratio of chitin reached 1.75 and 23.6 %, respectively. The saturated adsorption capacity of VhChit2 and VhChit6 adsorbed in 1 g of chitin was 48.5 and 33.4 mg. It was found that VhChit2 and VhChit6 had different adsorption sites on chitin, making more enzymes absorbed by chitin. Furthermore, the combined use of VhChit2 and VhChit6 increased their binding force of chitinases with the substrate. The synergistic action of VhChit2 and VhChit6 may be attributed to their different adsorption sites on chitin and the increased binding force with chitin.


Asunto(s)
Quitinasas , Vibrio , Quitinasas/química , Quitina/farmacología , Quitina/metabolismo , Dominio Catalítico
20.
Food Chem ; 401: 134112, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36099819

RESUMEN

Drying is an important process that can impart a different flavor to dried fish. The differences and sources of flavor of semi-dried golden pompano at different drying temperatures (40, 48, and 56 °C) were investigated, and the sensory quality, flavor substances, nonenzymatic reactions, and protein degradation were analyzed. Significant flavor differences were observed among different drying temperatures (P < 0.05), with several sensory properties showing superior results in the 40 °C group. Thirteen volatile compounds that contributed to the overall aroma were screened according to the relative odor activity value. Glu (umami taste) and Ala (sweet taste) were identified as key flavor substances based on the taste activity value. Nonanal, hexanal, heptanal, acetoin, pentadecane, and octanal represented the flavor markers. The flavor sources at higher drying temperatures included the joint action of lipid oxidation and the Maillard reaction, while those at lower temperature were lipid oxidation and protein degradation, which increased the aldehyde and free amino acid levels in the product, thus leading to the best flavor.


Asunto(s)
Manipulación de Alimentos , Compuestos Orgánicos Volátiles , Animales , Temperatura , Manipulación de Alimentos/métodos , Compuestos Orgánicos Volátiles/análisis , Acetoína , Aldehídos/análisis , Gusto , Odorantes/análisis , Peces , Aminoácidos , Lípidos
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