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1.
Environ Toxicol ; 39(6): 3537-3547, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38469959

RESUMO

The antioxidant properties of crocin are attracting interest, yet the underlying mechanisms by which crocin mitigates oxidative stress-induced intestinal damage have not been determined. This study aimed to elucidate the effects of crocin on oxidative stress, apoptosis, and intestinal epithelial injury in intestinal epithelial cells (IPEC-J2). Using an H2O2-induced oxidative stress model in IPEC-J2 cells, crocin was added to assess its effects. Cell viability and apoptosis were evaluated using methyl thiazolyl tetrazolium assays and flow cytometry. Additionally, oxidative stress markers, such as superoxide dismutase (SOD), catalase (CAT), reactive oxygen species (ROS), and malondialdehyde (MDA), were quantified. We investigated, in which cell oxidation and apoptosis were measured at the gene and protein levels and employed transcriptome analysis to probe the mechanism of action and validate relevant pathways. The results showed that crocin ameliorates H2O2-induced oxidative stress by reducing ROS and MDA levels and by countering the reductions in CAT, total antioxidant capacity, and SOD. Crocin also attenuates the upregulation of key targets in the Nrf2 pathway. Furthermore, it effectively mitigated IPEC-J2 cell apoptosis caused by oxidative stress, as evidenced by changes in cell cycle factor expression, apoptosis rate, mitochondrial membrane potential, and apoptosis pathway activity. In addition, crocin preserves the integrity of the intestinal barrier by protecting tight junction proteins against oxidative stress. Transcriptome sequencing analysis suggested that the mitochondrial pathway may be a crucial mechanism through which crocin exerts its protective effects. In summary, crocin decreases oxidative stress molecule formation, inhibits Nrf2 pathway activity, prevents apoptosis-induced damage, enhances oxidative stress resistance in IPEC-J2 cells, and maintains redox balance in the pig intestine.


Assuntos
Antioxidantes , Apoptose , Carotenoides , Peróxido de Hidrogênio , Estresse Oxidativo , Espécies Reativas de Oxigênio , Carotenoides/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Animais , Linhagem Celular , Peróxido de Hidrogênio/toxicidade , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Suínos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos
2.
J Appl Clin Med Phys ; 24(11): e14101, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37477628

RESUMO

PURPOSE: To investigate the dosimetric impact of the calculation boundaries and dose calculation algorithms of radiotherapy in head and neck cancer patients with an opened oral cavity connected to the exterior by a hollow intraoral positioning stent. METHODS AND MATERIALS: A homemade silicone phantom with an opened oral cavity was placed in a CIRS head phantom to model head and neck cancer patients with a hollow intraoral positioning stent. 3D-CRT plans were designed on CT images of the phantom in Monaco and Pinnacle3 treatment planning systems (TPSs) with the same beam parameters. The default boundary and manually extrapolated boundary were both adopted in these two TPSs to explore the dosimetric impact on treatment plans. The nanoDot™ optically stimulated luminescence dosimeters (OSLDs) were chosen to measure the planned dose surrounding the oral cavity of the head phantom after calibration. RESULT: The doses in the air cavity and two measuring points at the joint area were dramatically changed from 0.0, 92.4 and 148.8 cGy to 177.8, 244.2 and 244.1 cGy in Monaco after adopting the extrapolated boundary. While the calculated doses at the same place were changed from 61.2, 143.7 and 198.3 cGy to 175.4, 234.7 and 233.2 cGy in Pinnacle3 with a similar calculation boundary. For the Monaco TPS, the relative errors compared to the OSLD measured doses were 2.94 ± 1.93%, 0.53 ± 8.64%, 2.65 ± 1.87% and 3.93 ± 1.69% at 4 measuring positions. In contrast, the relative errors 4.03 ± 1.93%, 4.85 ± 8.64%, 7.61 ± 1.87% and 5.61 ± 1.69% were observed in Pinnacle3 . CONCLUSION: The boundary setting of an opened oral cavity in TPSs has a significant dosimetric impact on head and neck cancer radiotherapy. An extrapolated boundary should be manually set up to include the whole oral cavity in the dose calculation domain to avoid major dose deviations.


Assuntos
Neoplasias de Cabeça e Pescoço , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias de Cabeça e Pescoço/radioterapia , Radiometria/métodos , Imagens de Fantasmas , Radioterapia de Intensidade Modulada/métodos
3.
Sci Rep ; 14(1): 18628, 2024 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-39128912

RESUMO

Normal tissue complication probability (NTCP) models for radiation pneumonitis (RP) in lung cancer patients with stereotactic body radiation therapy (SBRT), which based on dosimetric data from treatment planning, are limited to patients who have already received radiation therapy (RT). This study aims to identify a novel predictive factor for lung dose distribution and RP probability before devising actionable SBRT plans for lung cancer patients. A comprehensive correlation analysis was performed on the clinical and dose parameters of lung cancer patients who underwent SBRT. Linear regression models were utilized to analyze the dosimetric data of lungs. The performance of the regression models was evaluated using mean squared error (MSE) and the coefficient of determination (R2). Correlational analysis revealed that most clinical data exhibited weak correlations with dosimetric data. However, nearly all dosimetric variables showed "strong" or "very strong" correlations with each other, particularly concerning the mean dose of the ipsilateral lung (MI) and the other dosimetric parameters. Further study verified that the lung tumor ratio (LTR) was a significant predictor for MI, which could predict the incidence of RP. As a result, LTR can predict the probability of RP without the need to design an elaborate treatment plan. This study, as the first to offer a comprehensive correlation analysis of dose parameters, explored the specific relationships among them. Significantly, it identified LTR as a novel predictor for both dose parameters and the incidence of RP, without the need to design an elaborate treatment plan.


Assuntos
Neoplasias Pulmonares , Pneumonite por Radiação , Radiometria , Radiocirurgia , Humanos , Pneumonite por Radiação/epidemiologia , Pneumonite por Radiação/etiologia , Neoplasias Pulmonares/radioterapia , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Incidência , Pulmão/efeitos da radiação , Dosagem Radioterapêutica , Idoso de 80 Anos ou mais , Planejamento da Radioterapia Assistida por Computador
4.
J Colloid Interface Sci ; 656: 68-79, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37984172

RESUMO

In CO2 cycloaddition reactions, hydrogen bond donor (HBD) groups are considered environmentally friendly substitutes for metals to promote epoxide ring-opening through interactions with nucleophilic anions. A core-shell structured ILs-based catalyst (mSiO2@MCM-NH2-OH) with dual hydrogen bond donors (-OH and -NH2) was synthesized by copolymerization strategy. Through in-depth characterization, it has been demonstrated that the catalyst (mSiO2@MCM-NH2-OH) possesses multiple catalytic active sites including -OH, -NH2, Br- groups, and the synergistic effect of double HBD groups (-OH and -NH2) and Lewis base (Br-) significantly improved the catalytic activity. Meanwhile, the core-shell structure of the catalyst effectively prevents the loss of active components, which makes the yield remain at about 94 % after 10 cycles. Based on Density Functional Theory (DFT) calculations, a synergistic catalytic mechanism, which involves dual hydrogen-bond donors (-OH and -NH2) and Lewis bases (Br-) was proposed. The cooperative interaction between -OH/-NH2 and Br- reduced the ring-opening barrier of epoxide from 58.6 to 32.0 kcal mol-1 significantly, and thereby facilitated the CO2 cycloaddition reaction.

5.
Front Physiol ; 14: 1261204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37920803

RESUMO

Adipose tissue is the most important energy storage organ in the body, maintaining its normal energy metabolism function and playing a vital role in keeping the energy balance of the body to avoid the harm caused by obesity and a series of related diseases resulting from abnormal energy metabolism. The dysfunction of adipose tissue is closely related to the occurrence of diseases related to obesity metabolism. Among various organelles, mitochondria are the main site of energy metabolism, and mitochondria maintain their quality through autophagy, biogenesis, transfer, and dynamics, which play an important role in maintaining metabolic homeostasis of adipocytes. On the other hand, mitochondria have mitochondrial genomes which are vulnerable to damage due to the lack of protective structures and their proximity to sites of reactive oxygen species generation, thus affecting mitochondrial function. Notably, mitochondria are closely related to other organelles in adipocytes, such as lipid droplets and the endoplasmic reticulum, which enhances the function of mitochondria and other organelles and regulates energy metabolism processes, thus reducing the occurrence of obesity-related diseases. This article introduces the structure and quality control of mitochondria in adipocytes and their interactions with other organelles in adipocytes, aiming to provide a new perspective on the regulation of mitochondrial homeostasis in adipocytes on the occurrence of obesity-related diseases, and to provide theoretical reference for further revealing the molecular mechanism of mitochondrial homeostasis in adipocytes on the occurrence of obesity-related diseases.

6.
Chemosphere ; 307(Pt 1): 135784, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35870609

RESUMO

Using co-substrates to enhance the metabolic activity of microbes is an effective way for high-molecular-weight polycyclic aromatic hydrocarbons removal in petroleum-contaminated environments. However, the long degradation period and exhausting substrates limit the enhancement of metabolic activity. In this study, Altererythrobacter sp. N1 was screened from petroleum-contaminated soil in Shengli Oilfield, China, which could utilize pyrene as the sole carbon source and energy source. Saturated aromatic fractions and crude oils were used as in-situ co-substrates to enhance pyrene degradation. Enzyme activity was influenced by the different co-substrates. The highest degradation rate (75.98%) was achieved when crude oil was used as the substrate because strain N1 could utilize saturated and aromatic hydrocarbons from crude oil simultaneously to enhance the degrading enzyme activity. Moreover, the phthalate pathway was dominant, while the salicylate pathway was secondary. Furthermore, the Rieske-type aromatic cyclo-dioxygenase gene was annotated in the Altererythrobacter sp. N1 genome for the first time. Therefore, the co-metabolism of pyrene was sustained to achieve a long degradation period without the addition of exogenous substrates. This study is valuable as a potential method for the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons.


Assuntos
Dioxigenases , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Carbono , Genômica , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pirenos/metabolismo , Salicilatos , Solo , Poluentes do Solo/análise
7.
Electrophoresis ; 32(15): 2004-12, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21739463

RESUMO

Hepatitis B virus (HBV) infection is the leading cause of liver cirrhosis and hepatocellular carcinoma worldwide. In recent decades, significant progress toward understanding the molecular virology and pathogenesis of HBV infection has been made. In addition, multiple treatment modalities have been developed for persons with HBV infection. In the present study, we demonstrated that IL-4 inhibits the expression of hepatitis B surface antigen and hepatitis B e antigen in a HBV stably transfected hepatocellular carcinoma cell line (HepG2.2.15). To reveal the anti-HBV mechanism of IL-4 by proteomics, 2-DE and MS technology were utilized to profile global changes in protein expression in HepG2.2.15 cells after IL-4 treatment. A total of 56 differentially expressed proteins were identified in IL-4-treated HepG2.2.15 cells. To find out the interaction of these changed proteins by bioinformatics, signaling network analysis with the STRING tool showed that the identified proteins are primarily involved in transcription and proteolysis. Taken together, these results offer valuable clues for understanding the molecular mechanisms of the IL-4-mediated anti-HBV response.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/imunologia , Interleucina-4/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/virologia , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Análise por Conglomerados , Eletroforese em Gel Bidimensional , Hepatite B/tratamento farmacológico , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/biossíntese , Antígenos E da Hepatite B/biossíntese , Interações Hospedeiro-Patógeno , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteômica/métodos , Reprodutibilidade dos Testes , Transdução de Sinais , Espectrometria de Massas em Tandem
8.
Chemosphere ; 269: 129436, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33385667

RESUMO

P-cresol is a highly toxic phenolic pollutant in coal chemical wastewater. The effective removal of p-cresol is of great significance to the ecological environment. In this study, the degradation of p-cresol by the Fe(III)-EDDS/H2O2 Fenton-like reaction modified by Mn2+ was investigated. The results showed that the removal rate of p-cresol could be significantly increased by the addition of Mn2+ under neutral and weakly alkaline conditions (pH 6.5-8.5). Acidic conditions (pH 3.5) were not conducive to the Fenton-like reaction. This is because a neutral or weakly alkaline environment is conducive to Mn2+-EDDS complex formation, which can produce O2·- to accelerate the reduction of Fe(III), and the efficiency of p-cresol degradation through a Fenton-like reaction catalyzed by the Fe(III)-EDDS complex is significantly improved. In addition, the degradation of EDDS through ·OH was reduced by O2·-, which maintained and stabilized the Mn2+-EDDS complex and Fe(III)-EDDS complex. Under neutral conditions, the optimal dosage of Fe(III) is 0.7 mM, and the optimal molar ratios are EDDS/Fe(III) = 1: 1, Mn2+/Fe(III) = 1: 1, and H2O2/Fe(III) = 15: 1. The addition of free radical clearance isopropanol and CHCl3 proved that ·OH was the main active substance in the p-cresol degradation process.


Assuntos
Peróxido de Hidrogênio , Manganês , Cresóis , Compostos Férricos , Concentração de Íons de Hidrogênio , Oxirredução
9.
Bioresour Technol ; 281: 296-302, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30826515

RESUMO

To investigate the potential application of Chlorella vulgaris in the treatment of coal gasification wastewater, the characteristics of phenol and p-cresol cometabolism by Chlorella vulgaris were studied, including phenol degradation, ammonia nitrogen removal, antioxidant enzyme activities, and phenol hydroxylase activity. The results showed that the highest tolerable concentrations of phenol and p-cresol for Chlorella vulgaris were 800 and 400 mg/L, respectively. During cometabolism, phenol at low concentrations (100 mg/L) significantly promoted the degradation of p-cresol. Meanwhile, the removal efficiency of ammonia nitrogen was approximately 60% and was not affected by variations in phenol concentration. Furthermore, the cometabolism of phenol and p-cresol was enhanced by improvement of phenol hydroxylase activity of Chlorella vulgaris after the addition of NaHCO3 as an exogenous nutrient. Therefore, Chlorella vulgaris has a great potential for the biochemical treatment of coal gasification wastewater.


Assuntos
Chlorella vulgaris/metabolismo , Cresóis/metabolismo , Fenol/metabolismo , Amônia/metabolismo , Carvão Mineral , Especificidade por Substrato , Águas Residuárias/química
10.
Bioresour Technol ; 273: 56-62, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30408644

RESUMO

Cometabolic degradation is an effective method to remove the polycyclic aromatic hydrocarbons (PAHs) with phenol as growth substrate from coal chemical wastewater (CCW). Unfortunately, the toxicity and low solubility of PAHs always restrict their degradation. In this study, Chryseobacterium sp. H202 was firstly isolated from the aerobic segment of CCW. Then, to improve the cometabolic degradation of PAHs, the effects of hydroxypropyl-ß-cyclodextrin (HPCD) were investigated. Phenanthrene removal was accelerated in the presence of phenol; however, the degradation of phenol was inhibited because of the toxicity of phenanthrene. Addition of 50 mg/L HPCD accelerated the degradation of phenol and effectively improved the phenanthrene removal rate by about 55%. Inclusion of HPCD appeared to increase the apparent solubility and reduce the toxicity of phenanthrene, thereby improving the cometabolic degradation of phenol and phenanthrene. Therefore, HPCD can enhance the degradation of phenanthrene with phenol as the growth substrate during CCW treatment.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/metabolismo , Chryseobacterium/metabolismo , Fenantrenos/metabolismo , Fenóis/metabolismo , Solubilidade
11.
Front Chem ; 7: 458, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316968

RESUMO

Introducing electron-rich nitrogen atoms to ordered mesoporous carbons (OMC) as supports for noble metal catalysts, not only improves the hydrophilic properties of a mesoporous carbon surface, but also enhances the coordination and binding abilities of metal ion. In the present work, nitrogen-doped ordered mesoporous carbons (NOMCs) were successfully fabricated via a facile hydrothermal self-assembly. The prepared NOMCs were characterized through powder X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption isotherm. The analyses demonstrated that the NOMCs prepared at a pyrolysis temperature of 750°C possessed an ordered 2D hexagonal mesoporous structure, a high graphitization degree, large surface area, and a well-distributed pore size. In particular, NOMCs could anchor Pd nanoparticles uniformly because of the introducing N atoms with strong electronegativity, which were selected as efficient catalysts for the partial oxidation of benzyl alcohol to benzaldehyde. Approximately 24.63% conversion with 85.71% selectivity to benzaldehyde was obtained without using any solvent by molecular O2 oxidation. Most importantly, the TOF value of the catalyst in the reaction system was up to 8698 h-1. After five runs reaction, TOF and selectivity of the catalyst remained essentially same. Hence, the proposed catalyst has a potential engineering application value.

12.
Environ Health Prev Med ; 7(1): 19-21, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21432286

RESUMO

Shaanxi Province located at Midwest inland of China was a typical iodine deficient disorders region. To investigate iodine and selenium levels of neonates in the Shaanxi sub-clinical cretinism region of China after supplement of iodine salt for nearly twenty years. We collected 56 umbilical cord blood samples from cretinous regions of Yijun County (a selenium deficient region) north of Shaanxi Province and Ziyang County (a selenium-enriched region) south of the province and from Lintong in Xi'an (a non-cretinous region for control). Among these samples 17 were collected from Ziyang, 20 from Lintong and 19 from Yijun. Seven trace elements of iodine, selenium, zinc, copper, iron, calcium and magnesium in the umbilical cord blood samples were measured and the results were processed statistically. There were no significant differences in the levels of iodine among all three counties. However, the level of selenium in Ziyang was the highest and in Yijun it was the lowest. The other trace elements such as Cu Zn Fe and Mg showed no significant difference among the three counties except for the Ca level which was lower in Yijun.The regression equation was established with the backward method of multiple regression was: Se=0.180+0.00006654 Fe-0.006 Cu-0.005956 Mg+0.1.

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