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2.
Heliyon ; 10(3): e24674, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38314274

RESUMO

Addressing the measurement of corporate sustainable development performance (SDP) in economic, social, and environmental dimensions is a pressing global challenge. This study investigates the intrinsic impact mechanisms of the top management team's transactive memory system (TMT TMS) on SDP within Chinese manufacturing firms. It extends the analysis by introducing opportunity alertness (OA) as a moderating variable and organizational resilience (OR) as a mediating variable. Notably, OA was found to have a moderating mediation effect on the TMT TMS-OR-SDP pathway. Data from 294 executives was collected through non-probability convenience sampling. Initially, exploratory factor analysis was conducted utilizing SPSS; confirmatory factor analysis was performed with the aid of AMOS. Additionally, hierarchical regression and the SPSS PROCESS macro were employed to test the hypothesized models and paths of influence. The results illuminate the positive impact of TMT TMS on SDP through the enhancement of OR, a relationship further strengthened by OA. This study adds to the theoretical understanding and offers practical insights for optimizing TMT TMS and OA to achieve corporate sustainable development.

3.
World Neurosurg ; 179: e348-e358, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37634669

RESUMO

BACKGROUND: Accurately predicting the risk of lower extremity (LE) radiating pain after surgery is an important endeavor for spinal surgeons. Our study aimed to identify risk factors for LE radiating pain after decompression with full-endoscopic lumbar discectomy (FELD) and develop a nomogram. METHODS: We retrospectively reviewed the medical data of patients with lumbar disc herniation who underwent FELD. Two hundred thirty-five patients diagnosed at our hospital from January 2015 to December 2020 were used for model development. The independent risk factors for LE radiating pain after surgery were determined by least absolute shrinkage and selection operator logistic regression and multivariate logistic regression analysis. A nomogram was developed to predict the risk of LE radiating pain based on independent risk factors. Receiver operating characteristic curve, calibration curve, and decision curve analyses were used to evaluate the predictive performance. The nomogram was further verified by an independent cohort. RESULTS: Three hundred seventy-five patients were enrolled in this study, with 102 patients in the training cohort reporting LE radiating pain after FELD, while 133 patients did not. In the validation cohort, 57 patients reported LE radiating pain after FELD, while 83 patients did not. The model was established by multivariate logistic regression analysis. The risk factors included a higher Michigan State University classification of herniated discs, increased disease course, increased time of surgery, reduced lateral recess width, and an interlaminar surgical approach, compared to transforaminal approach. The C-indices and the area under the receiver operating characteristic curve of the predictive model demonstrated good discrimination. Good predictive performance and accuracy were also observed in the validation cohort. CONCLUSIONS: A novel nomogram for predicting recurrent LE radiating pain within 1 week after FELD was established and validated. More aggressive pain management strategies should be considered for patients at high risk of LE radiating pain after surgery, as predicted by this model.


Assuntos
Deslocamento do Disco Intervertebral , Nomogramas , Humanos , Estudos Retrospectivos , Discotomia/efeitos adversos , Deslocamento do Disco Intervertebral/complicações , Dor/etiologia , Extremidade Inferior/cirurgia , Vértebras Lombares/cirurgia
4.
Clin Immunol ; 250: 109320, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019423

RESUMO

Interleukin (IL)-22 regulates host defense. This study investigated the predominant IL-22-producing cell subsets under HBV associated immune stages. We found circulating IL-22-producing CD3 + CD8- T cells were significantly increased in immune active (IA) stage than those in immunotolerant stage, inactive carrier and healthy controls (HCs). The plasma IL-22 level was higher in IA and HBeAg-negative CHB compared to HCs. Importantly, CD3 + CD8- T cells were identified as the predominant source of plasma IL-22 production. Up-regulated IL-22-producing CD3 + CD8- T cells obviously correlated with the grade of intrahepatic inflammation. The proportions of IL-22-producing CD3 + CD8- T cells were significantly down-regulated after 48 weeks of Peg-interferon treatment, and the differences were of great significance in patients with normalize ALT levels at 48 weeks, rather than those with elevated ALT levels. In conclusion, IL-22 might play a proinflammatory function in. chronic HBV infected patients with active inflammation and Peg-interferon treatment could attenuate the degree of liver inflammation through down-regulating IL-22-producing CD3 + CD8- T cells.


Assuntos
Vírus da Hepatite B , Interferons , Humanos , Linfócitos T CD8-Positivos , Inflamação , Complexo CD3/imunologia , Interleucina 22
5.
ACS Appl Mater Interfaces ; 15(13): 17364-17376, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36973948

RESUMO

Two-dimensional (2D) materials have potential application and wide development prospects in photoelectron and spintronic devices. However, the properties of different growth conditions are challenging to study in the future. This, in turn, hinders further research into 2D materials and the manufacture of high-quality devices. A comprehensive understanding of the ultrafast laser spectroscopy and dynamics that take into account the substrate-transition metal dichalcogenide (TMD) interaction is lacking. Here, the strain effect is elucidated by systematically investigating the interfacial interaction between different substrates and MoS2. The strain and interface engineering of MoS2/seeds layer heterointerface and light-matter coupling are discussed in the Raman and photoluminescence spectra. The dramatic enhanced PL originates from the phase transition of MoS2 on different substrates and electron-hole pairs dissociated by exciton screening effect. Finite-difference time-domain simulation confirmed that the electric field, magnetic field, and polarization field of the heterojunction system changed after the strain was applied. In addition, based on the dependence of physical parameters of MoS2, the relative numerical changes of physical parameters of MoS2 films on different substrates as well as the photoelectric transfer, strain, and charge doping levels on the surface or interface will provide a direction for optimizing the selection of various devices.

6.
Biomed Environ Sci ; 35(8): 688-698, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127781

RESUMO

Objective: This study optimizes three-dimensional (3D) culture conditions of HepG2 using response surface methodology (RSM) based on the VitroGel system to facilitate the cell model in vitro for liver tissues. Method: HepG2 cell was 3D cultured on the VitroGel system. Cell viability was detected using Cell Counting Kit-8 (CCK-8) assay of HepG2 lived cell numbers. The proliferation of HepG2 cell and clustering performance was measured via fluorescence staining test. Albumin concentration in the culture medium supernatant as an index of HepG2 cell biological function was measured with ELISA kit. Independent factor tests were conducted with three key factors: inoculated cell concentration, cultured time, and dilution degree of the hydrogel. The preliminary results of independent factor tests were used to determine the levels of factors for RSM. Result: The selected optimal culture conditions are as follows: concentration of inoculated cells was 4.44 × 10 5/mL, culture time was 4.86 days, and hydrogel dilution degree was 1:2.23. The result shows that under optimal conditions, the predicted optical density (OD) value of cell viability was 3.10 and measured 2.978 with a relative error of 3.94%. Conclusion: This study serves as a reference for the 3D HepG2 culture and constructs liver tissues in vitro. Additionally, it provides the foundation for repeated dose high-throughput toxicity studies and other scientific research work.


Assuntos
Técnicas de Cultura de Células , Albuminas , Técnicas de Cultura de Células/métodos , Células Hep G2 , Humanos , Hidrogéis
7.
Nanoscale ; 14(39): 14670-14682, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36165101

RESUMO

Two-dimensional lateral group-VIB transition metal dichalcogenides (TMDs) have attracted much attention in the fast evolving field of advanced photoelectric functional materials, but their controllable fabrication is challenging. Herein, an emerging synthetic route for sulfurization of tungsten oxide was developed. During the hydrothermal reaction, the optimization of the precursor selection and synthesis parameters led to the tunable properties of WO3-WSxOy-WS2 nanostructures. The vulcanization was thermodynamically favorably at low temperatures and in an environment with a sufficient S source, wherein WO3 was reduced by H atoms to WO3-x, and S atoms were preferentially adsorbed on O vacancies. The WSxOy nanostructures have a narrow band-gap attributed to the effect of S on the valence band top and electronic density of states by density functional theory. The photocurrent response and charge transfer properties of WSxOy were improved due to the charge transport between WS2 and WO3. Understanding the formation and transformation of WS2 nanostructures in solution contributes to the discovery of the important structure-efficiency relationship, which may be extended to other TMDs systems. Hence, extensive research efforts are still needed to develop safer and more efficient synthesis and modification methods to fully utilize the distinctive advantageous properties of TMDs in the photoelectric field.

8.
Phys Chem Chem Phys ; 24(31): 18523-18528, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35894826

RESUMO

Electrodes can adsorb different reaction intermediates under electrochemical conditions, which in turn significantly affect their electrochemical performance. This complex phenomenon attracts continuous interest in both science and industry for understanding the co-electrosorbed structure and activity under electrochemical conditions. Here, we report the first theoretical attempt by combining the machine-learning-based global optimization (SSW-NN method) and modified Poisson-Boltzmann continuum solvation (CM-MPB) based on first-principles calculations to elucidate the potential-dependent co-electrosorbed species on the Pd(110) surface. We reveal the potential-dependence adsorption/absorption hydrogen phases, the phase transition of α-Hri/Pd to ß-Hri/Pd, and the co-electrosorbed Hri-NHy surface structures. In particular, we found that Hri-NH2 and Hri-NH3 are favorable intermediates for the N2 reduction reaction, and the subsurface H is the key species responsible for NH2 hydrogenation on the Pd(110) electrode.

9.
J Clin Hypertens (Greenwich) ; 24(7): 908-917, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35739356

RESUMO

This study aims to investigate the relationship between waist circumference and hypertension risk in normal-weight/overweight individuals with normal cardiometabolic profiles. The authors included 7217 normal-weight and overweight individuals with normal cardiometabolic profiles from the 2001 to 2014 US National Health and Nutrition Examination Survey. The authors summarized demographic characteristics, cardiometabolic profiles, and behavioral factors across waist circumference quartiles. Then, in the logistic regression analysis, the authors observed a positive and significant association between waist circumference (as a continuous variable) and the prevalence of hypertension in all three models (nonadjusted, minimally adjusted, and fully adjusted), with odds ratios (95% confidence intervals) of 1.76 (1.65-1.86), 1.29 (1.20-1.39), and 1.24 (1.09-1.40), respectively. When analyzed as a categorical variable, individuals in the highest waist circumference group had a 1.48-fold increased risk of hypertension than the lowest group in the fully adjusted model. Moreover, the Cox regression analysis revealed a positive and significant association between waist circumference and all-cause mortality in individuals with hypertension in the nonadjusted model (HR, 1.27; 95% CI, 1.10-1.47) and the fully adjusted model (HR, 1.59; 95% CI, 1.22-2.06). In conclusions, our results showed that, even in those with normal metabolic profiles, high waist circumference was significantly associated with the increased prevalence of hypertension. And once hypertension has been established, patients with high waist circumference showed elevated all-cause mortality. Therefore, waist circumference should be routinely measured and controlled regardless of metabolic profiles.


Assuntos
Hipertensão , Índice de Massa Corporal , Humanos , Hipertensão/diagnóstico , Metaboloma , Inquéritos Nutricionais , Sobrepeso/complicações , Sobrepeso/epidemiologia , Fatores de Risco , Circunferência da Cintura
10.
RSC Adv ; 12(5): 3013-3026, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35425285

RESUMO

In this paper, plasma silver (Ag) modified zinc oxide (ZnO) (AZO) was used to form AZO nanomaterials (including AZO nanofilms (NFm), AZO nanowires (NWs) and AZO nanoflowers (NFw)) in a two-step-controlled manner to investigate the effect of compounding different contents of Ag on the linear optical aspects of ZnO materials. The growth mechanism of the AZO nanomaterials with different strategies is discussed. If Ag nanoparticles (NPs) grow on the ZnO NFm surface, they first grow with ZnO as the core and then self-core into islands, which are undoubtedly influenced by factors such as the growth mechanism of ZnO as well as Ag. If Ag is grown on the surface of the ZnO NWs and ZnO NFw, it is more likely to self-core owing to factors such as the roughness of the ZnO NWs and ZnO NFw surfaces. The AZO nanomaterials have excellent optical properties based on the surface plasmon resonance, local electromagnetic field and charge transfer mechanism between Ag and ZnO. With the increase in Ag content, the absorption edges of AZO NFm are red-shifted, and the absorption edges of AZO NWs and AZO NFw are first blue-shifted and then red-shifted. The results show that AZO nanomaterials prepared using different methods not only have different growth morphologies, but also have different optical properties with potential for the preparation of optical devices.

11.
Food Chem ; 387: 132823, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398680

RESUMO

The current study analysed concentrations of furan and its derivatives in coffee products commercially available in China based on an improved headspace gas chromatography-mass spectrometry (HS-GC-MS) method and estimated health risks. A total of 101 samples of coffee products on the Chinese market was analysed. Furan (98%, ND-6569 µg/kg) and 2-methylfuran (100%, 2-29639 µg/kg) were the compounds with the highest concentrations and detection rates in coffee products. The mean dietary exposure of Chinese consumers to furan and the sum of furan, 2-methylfuran and 3-methylfuran in coffee products was 0.09 and 0.46 µg/kg bw/day, respectively. For the neoplastic effects of furan, the margin of exposure (MOE) was 14,556 for the mean dietary exposure of consumers. For the non-neoplastic effects of furan, MOEs were 711 and 139 for furan and the sum of furan, 2-methylfuran and 3-methylfuran, respectively. Overall, a health concern is indicated for coffee consumers with MOEs below 10000.


Assuntos
Café , Furanos , China , Café/química , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos
12.
Zhongguo Zhen Jiu ; 42(2): 162-6, 2022 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-35152580

RESUMO

OBJECTIVE: To compare the curative effect of Tiaoshen acupuncture combined with artificial tears and artificial tears alone for dry eye syndrome with yin deficiency of liver and kidney. METHODS: A total of 70 patients of dry eye syndrome with yin deficiency of liver and kidney were randomized into an acupuncture combined with medication group (35 cases, 2 cases dropped off) and a medication group (35 cases, 3 cases dropped off). In the medication group, 0.1% sodium hyaluronate eye drop was applied, 3 times a day, 1 drop each time. On the basis of the treatment as the medication group, Tiaoshen acupuncture was applied at Shenting (GV 24), Shenmen (HT 7), Benshen (GB 13), Taixi (KI 3), Taichong (LR 3), Guangming (GB 37), Fengchi (GB 20), Tongziliao (GB 1), Yuyao (EX-HN 4) in the acupuncture combined with medication group, Tongziliao (GB 1) and Yuyao (EX-HN 4) were connect with electroacupuncture, the needles were retained for 30 min, once a day, 6 times a week. Both groups were treated for 2 weeks. Before and after treatment, the clinical symptom score, SchirmerⅠtest (SⅠT), break-up time (BUT), corneal fluorescein staining (FL) score and Hamilton anxiety scale (HAMA) score were observed in the two groups, and the clinical efficacy was compared in the two groups. RESULTS: Compared before treatment, the clinical symptom scores, corneal FL and HAMA scores were decreased (P<0.05), the levels of SⅠT and BUT were increased after treatment in the two groups (P<0.05). After the treatment, the clinical symptom score, FL and HAMA scores in the acupuncture combined with medication group were lower than the medication group (P<0.05), the levels of SⅠT and BUT in the acupuncture combined with medication group were higher than the medication group (P<0.05). The total effective rate in the acupuncture combined with medication group was 90.9% (30/33), which was higher than 71.9% (23/32) in the medication group (P<0.05). CONCLUSION: Tiaoshen acupuncture combined with artificial tears could promote the secretion of tears for patients of dry eye syndrome with yin deficiency of liver and kidney, repair corneal defect and prolong tear film break-up time, and alleviate anxiety state, its curative effect is better than simple artificial tears.


Assuntos
Terapia por Acupuntura , Síndromes do Olho Seco , Pontos de Acupuntura , Síndromes do Olho Seco/terapia , Humanos , Rim , Fígado , Resultado do Tratamento , Deficiência da Energia Yin/terapia
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(3): 881-886, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34105488

RESUMO

OBJECTIVE: To explore the influencing factors in children with chronicity immune thrombocytopenia (ITP), and to provide basis for judging the prognosis and treatment in children with ITP. METHODS: The clinical data of children with ITP admitted to The Second Affiliated Hospital of Anhui Medical University in the past 5 years were retrospectively analyzed and followed up for more than 1 year. According to the inclusion criteria, the eligible cases (328 cases in total) were selected and collected through medical record system retrieval, outpatient clinic and telephone follow-up. Independent influencing factors affecting the prognosis of children with ITP were obtained through single-factor and multi-factor logistic analysis, and their predictive value for the prognosis of ITP in children were evaluated. RESULTS: Of 328 children with ITP, 208 were newly diagnosed with ITP (64%), 54 were persistent ITP (16%), 66 were chronic ITP (20%), and the remission rate within 1 year was 79.9%. The results of univariate analysis showed that, age, pre-morbidity history of infection and vaccination, antinuclear antibodies, initial absolute lymphocyte count(ALC) and treatment options were related to the prognosis of the children (P<0.05). Multivariate analysis showed that the history of infection and vaccination before onset, initial treatment options, and ALC at the time of initial diagnosis were independent factors affecting the prognosis of children with ITP (P<0.05). The time for platelet recovery to 100×109/L in the initial treatment group combined with intravenous immunoglobulin (IVIG) was shorter than that in the single corticosteroids group (P<0.01). The receivers operating characteristic (ROC) was drawn with the development of chronic disease (course >12 months) as state variable and ALC or ALC combined with preceding infection or vaccination history as test variable. The results showed that when the absolute value of lymphocytes was 3.80×109/L, the area under the curve was the largest (0.787), the sensitivity was 80.6%, and the specificity was 65.53% (P<0.01), the combined results showed that the maximum area under the curve was 0.859, the sensitivity was 77.61%, and the specificity was 78.41%. CONCLUSION: The initial treatment plan combined with IVIG can reduce the occurrence of chronicity in children with ITP, and its efficacy is better than that of the single corticosteroids group (the platelet recovery time is shorter); history of preceding infection or vaccination, ALC at the time of initial diagnosis are independent factors affecting the prognosis of children with ITP, and the combination of the two shows a better predictive value for the prognosis.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Criança , Humanos , Imunoglobulinas Intravenosas , Prognóstico , Estudos Retrospectivos
14.
BMC Pediatr ; 21(1): 126, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33722205

RESUMO

BACKGROUND: Phenylketonuria (PKU) is a genetic metabolic disorder in which patients have no ability to convert phenylalanine to tyrosine. Several autoimmune diseases have been reported to combine with PKU, co-existent of PKU and Juvenile Idiopathic Arthritis (JIA) has not been presented. CASE PRESENTATION: The girl was diagnosed with PKU at the age of 1 month confirmed by molecular data. At the age of 3.5 years, she presented with pain and swelling of her right ankle, right knee, and right hip joint. After a serial of examinations, she was diagnosed with JIA and treated with a nonsteroidal anti-inflammatory drug. CONCLUSIONS: We report a rare case of a 4-year-old girl with PKU and JIA, which supports a possible interaction between PKU and JIA. Long-term metabolic disturbance may increase the susceptibility to JIA. Further chronic inflammation could alter the metabolism of tryptophan and tyrosine to increase blood Phe concentration. In addition, corticosteroid and methotrexate therapy for JIA may increase blood Phe concentration.


Assuntos
Artrite Juvenil , Fenilcetonúrias , Corticosteroides/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Juvenil/complicações , Artrite Juvenil/diagnóstico , Artrite Juvenil/tratamento farmacológico , Pré-Escolar , Feminino , Humanos , Fenilalanina , Fenilcetonúrias/complicações , Fenilcetonúrias/diagnóstico
15.
Medicine (Baltimore) ; 99(35): e21920, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871927

RESUMO

INTRODUCTION: Collagen colitis (CC) is a microscopic colitis diagnosed by mucosal biopsy and is extremely rare in children. PATIENT CONCERNS: We reported a child with severe persistent diarrhea that could not be relieved with traditional diarrheal treatment. No abnormalities were found after multiple colonoscopies. DIAGNOSES: A significant increase in total IgE levels was found in the patient's blood. He had a history of mild chronic allergic rhinitis and slightly intermittent wheezing. However, we found that the child had a hyperallergic reaction to multiple respiratory antigens and had mild pulmonary dysfunction. Finally, colonoscopy with biopsy identified the diagnosis of CC. INTERVENTION: Considering that a respiratory allergic reaction was one of the causes of diarrhea, anti-allergic treatment was given to the child, and his severe diarrhea was soon relieved. Corticosteroid treatment was suggested to the patient, but his parents firmly refused steroid therapy. According to the patient's specific allergic reaction to mites, desensitization treatment was finally chosen for him. OUTCOMES: After 1 year of desensitization for dust mites, the patient's respiratory symptoms improved, total IgE levels decreased, autoantibodies declined, and diarrhea did not reoccur. Colonoscopy with biopsy showed a significant improvement in pathology. CONCLUSION: CC in children is rare, and childhood CC induced by a respiratory allergic reaction has not been previously reported. Therefore, this is a special case of CC in a patient who was cured with anti-allergy treatments and desensitization instead of steroid therapy.


Assuntos
Colite Colagenosa/diagnóstico , Colite Colagenosa/etiologia , Diarreia/etiologia , Hipersensibilidade Respiratória/complicações , Antialérgicos/uso terapêutico , Biópsia , Criança , Doença Crônica , Colite Colagenosa/terapia , Colonoscopia , Dessensibilização Imunológica , Diarreia/terapia , Humanos , Masculino , Hipersensibilidade Respiratória/terapia
16.
Korean J Physiol Pharmacol ; 24(1): 19-26, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31908571

RESUMO

Medium- and long-chain triglyceride (MCT/LCT) propofol is widely used as an intravenous anesthetic, especially in the intensive care unit. The present study aimed to assess whether MCT/LCT propofol is safe in the hyperlipidemic population for long-term use. Free fatty acids (FFAs) were used to establish high-fat stimulation of HepG2 and Huh7 cells. Subsequently, these cells were treated with propofol at the concentration of 0, 4, or 8 µg/ml for 24 and 48 h. The results indicated that the cell viability was notably decreased when the cells were stimulated with 2 mmol/L FFAs and treated with 12 µg/ml MCT/LCT propofol. Accordingly, we chose 2 mmol/L FFAs along with 4 and 8 µg/ml MCT/LCT propofol for the subsequent experiments. Four and 8 µg/ml MCT/LCT propofol inhibited FFA-induced lipid accumulation in the cells and significantly reversed acetyl coenzyme A carboxylase (ACC) activity. In addition, MCT/LCT propofol not only significantly promoted the phosphorylation of AMPK and ACC, but also reversed the FFA-induced decreased phosphorylation of AMPK and ACC. In conclusion, MCT/LCT propofol reverses the negative effects caused by FFAs in HepG2 and Huh7 cells, indicating that MCT/LCT propofol might positively regulate lipid metabolism.

17.
Journal of Preventive Medicine ; (12): 1200-1203, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-875774

RESUMO

Objective@#To establish a method for the determination of furans in tea by headspace-gas chromatographic mass spectrometry. @*Methods@#The 20% sodium chloride solution and isotope internal standards were added to the crushed and weighed tea sample. Furan, 2-methylfuran, 3-methylfuran, 2,5-dimethylfuran were separated by HP-PLOT Q capillary column and then determined by gas chromatography mass spectrometry with electron impact ionization mode.@*Results@# In the range of 5-400 ng, good linear relationships were observed in the four furan compounds, with the correlation coefficients ranging from 0.999 2 to 0.999 6. The detection limits ranged from 0.2 to 1.9 μg/kg, the quantification limit ranged from 0.4 to 3.1 μg/kg. The recovery rates of furans ranged from 95.4% to 128.2% when spiked at 5.0, 20.0 and 100.0 μg/kg, and the relative standard deviations ranged from 0.8% to 11.3%. Eighty-one tea samples were determined, the concentration of four furan compounds was highest in black tea, followed by dark tea, oolong tea, green tea and scented tea. @*Conclusion@# Headspace-gas chromatography-mass spectrometry can reduce the matrix interference of tea, and meet the requirements in the linear range, recovery and precision, which is suitable for simultaneous determination of four furan compounds in tea.

18.
Front Aging Neurosci ; 11: 316, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849636

RESUMO

The degeneration of dopaminergic (DA) neurons in Parkinson's disease (PD) is related to inflammation and oxidative stress. Anti-inflammatory agents could reduce the risk or slow the progression of PD. Catalpol, an iridoid glycoside extracted from the roots of Rehmannia radix, has been reported to reduce the release of inflammatory factors and exert neuroprotective effects. 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP)-treated mice were used as the PD model and the roles of catalpol on DA neurons and its potential mechanism were investigated in this study. We found that catalpol administration mitigated the loss of DA neurons induced by MPTP and increased exploratory behavior along with tyrosine hydroxylase (TH) expression, which was accompanied by astrocyte and microglia activation. Importantly, catalpol administration significantly inhibited MPTP-triggered oxidative stress, restored growth-associated protein 43 (GAP43) and vascular endothelial growth factor (VEGF) levels. Further, we found that catalpol suppressed the activation of MKK4/JNK/c-Jun signaling, and reduced the pro-inflammatory factors and inflammasome in the mouse model of PD. Our results suggest that catalpol relieves MPTP-triggered oxidative stress, which may benefit to avoid the occurrence of chronic inflammatory reaction. Catalpol alleviates MPTP-triggered oxidative stress and thereby prevents neurodegenerative diseases-related inflammatory reaction, highlighting its therapeutic potential for the management of PD symptoms.

19.
Soft Matter ; 15(47): 9710-9720, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31729500

RESUMO

Poly(butylene succinate-co-propylene succinate) (PBSPS) was polymerized using succinic acid, 1,4-butanediol, 1,3-propanediol, and glycerol (GC). The PBSPS copolyester with a BS/PS ratio of 7/3 has a low melting point (Tm, 80 °C) and crystallization temperature (Tc, 20 °C) in addition to excellent thermal stability with a thermal degradation temperature (Td) above 300 °C. Isodimorphism was observed for 30-50 mol% PS, lowering Tm and Tc. The featured crystalline lattices (021) and (110) of PBS at 2θ = 21.5° and 22.5° gradually disappeared with PS content greater than 50 mol% and transformed into a PPS crystalline lattice at 2θ = 22.3°. Young's modulus decreased with increasing PS content due to crystallinity loss. Wide-angle X-ray diffraction demonstrated that the chain movement regularity was affected by the GC content, reducing the crystallinity. The PBSPS copolyesters were elastic with 0.001 mol% GC but became rigid with GC content greater than 0.01 mol%. The chain conformation was flexible for 0.001-0.01 mol% GC and exhibited an irregular steric architecture for 0.02-0.03 mol% GC due to more GC acting as nodes. Thus, the thermal and mechanical properties of the synthesized bio-based PBSPS copolyesters can be controlled by adjusting the GC content; therefore, such copolyesters are suitable for medical support, coating, and phase-change material applications.


Assuntos
Butileno Glicóis/química , Glicerol/química , Polímeros/química , Succinatos/química , Cristalização , Elasticidade , Temperatura
20.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2266-2273, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359652

RESUMO

A high-content GABA was found in Sojae Semen Praeparatum(SSP), which is a famous traditional Chinese medicine and officially listed in Chinese Pharmacopoeia. To screen out and identify GABA-producing microbes from samples at different time points during the fermenting process of SSP, traditional microbiological methods combined with molecular biological methods were used to study the predominant GABA-producing microorganisms existing in the fermenting process of SSP. This study would lay a foundation for further studying the processing mechanism of SSP. The fermenting process of SSP was based on Chinese Pharmacopoeia(2010 edition), and samples were taken at different time points during the fermenting process of SSP. The bacteria and fungi from samples at different time points in the fermenting process of SSP were cultured, isolated and purified by selective medium, and dominant strains were selected. The dominant bacteria were cultured in the designated liquid medium to prepare the fermentation broths, and GABA in the fermentation broth was qualitatively screened out by thin-layer chromatography. The microbial fermentation broth with GABA spots in the primary screening was quantitatively detected by online pre-column derivatization and high performance liquid chromatography established in our laboratory. GABA-producing microorganisms were screened out from predominant strains, and their GABA contents in fermentation broth were determined. The DNA sequences of GABA-producing bacteria and fungi were amplified using 16S rDNA and 18S rDNA sequences by PCR respectively. The amplified products were sequenced, and the sequencing results were identified through NCBI homology comparison. Molecular biological identification was made by phylogenetic tree constructed by MEGA 7.0 software. Through the homology comparison of NCBI and the construction of phylogenetic tree by MEGA 7.0 software, nine GABA-producing microorganisms were screened out and identified in this study. They were Bacillus subtilis, Enterococcus faecium, E. avium, Aspergillus tamarii, A. flavus, A. niger, Cladosporium tenuissimum, Penicillium citrinum and Phanerochaete sordida respectively. For the first time, nine GABA-producing microorganisms were screened out and identified in the samples at different time points during the fermenting process of SSP in this study. The results indicated that multiple predominant GABA-producing microorganisms exist in the fermenting process of SSP and may play an important role in the formation of GABA.


Assuntos
Bactérias/classificação , Fermentação , Fungos/classificação , Glycine max/microbiologia , Ácido gama-Aminobutírico/biossíntese , Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão , Fungos/metabolismo , Filogenia
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