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1.
Genome Res ; 32(1): 55-70, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34903527

RESUMO

Human papillomavirus (HPV) causes 5% of all cancers and frequently integrates into host chromosomes. The HPV oncoproteins E6 and E7 are necessary but insufficient for cancer formation, indicating that additional secondary genetic events are required. Here, we investigate potential oncogenic impacts of virus integration. Analysis of 105 HPV-positive oropharyngeal cancers by whole-genome sequencing detects virus integration in 77%, revealing five statistically significant sites of recurrent integration near genes that regulate epithelial stem cell maintenance (i.e., SOX2, TP63, FGFR, MYC) and immune evasion (i.e., CD274). Genomic copy number hyperamplification is enriched 16-fold near HPV integrants, and the extent of focal host genomic instability increases with their local density. The frequency of genes expressed at extreme outlier levels is increased 86-fold within ±150 kb of integrants. Across 95% of tumors with integration, host gene transcription is disrupted via intragenic integrants, chimeric transcription, outlier expression, gene breaking, and/or de novo expression of noncoding or imprinted genes. We conclude that virus integration can contribute to carcinogenesis in a large majority of HPV-positive oropharyngeal cancers by inducing extensive disruption of host genome structure and gene expression.


Assuntos
Alphapapillomavirus , Proteínas Oncogênicas Virais , Neoplasias Orofaríngeas , Alphapapillomavirus/metabolismo , Carcinogênese , Humanos , Proteínas Oncogênicas Virais/genética , Neoplasias Orofaríngeas/genética , Papillomaviridae/genética , Papillomaviridae/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Integração Viral/genética
2.
J Exp Bot ; 75(11): 3452-3466, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38497815

RESUMO

The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible for the fragrance and pharmacological properties of agarwood. O-Methyltransferases (OMTs) are necessary for the biosynthesis of methylated PECs, but there is little known about OMTs in Aquilaria sinensis. In this study, we identified 29 OMT genes from the A. sinensis genome. Expression analysis showed they were differentially expressed in different tissues and responded to drill wounding. Comprehensive analysis of the gene expression and methylated PEC content revealed that AsOMT2, AsOMT8, AsOMT11, AsOMT16, and AsOMT28 could potentially be involved in methylated PECs biosynthesis. In vitro enzyme assays and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 6-methoxy-2-(2-phenylethyl)chromone. A transient overexpression experiment in the variety 'Qi-Nan' revealed that AsOMT11 and AsOMT16 could significantly promote the accumulation of three major methylated PECs. Our results provide candidate genes for the mass production of methylated PECs using synthetic biology.


Assuntos
Metiltransferases , Proteínas de Plantas , Thymelaeaceae , Thymelaeaceae/genética , Thymelaeaceae/metabolismo , Thymelaeaceae/enzimologia , Metiltransferases/metabolismo , Metiltransferases/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Cromonas/metabolismo , Madeira/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Metilação , Regulação da Expressão Gênica de Plantas , Flavonoides
3.
BMC Public Health ; 24(1): 1823, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38977991

RESUMO

BACKGROUND: Medical disputes, which are prevalent in China, are a growing global public health problem. The Chinese government has proposed third-party mediation (TPM) to resolve this issue. However, the characteristics, efficiency, and influencing factors of TPM in resolving medical disputes in public hospitals in China have yet to be determined. METHODS: We conducted a systematic study using TPM records from medical disputes in Gansu Province in China from 2014 to 2019. A χ2 test was used to compare differences between groups, and binary logistic analysis was performed to determine the factors influencing the choice of TPM for resolving medical disputes. RESULTS: We analyzed 5,948 TPM records of medical disputes in Gansu Province in China. The number of medical disputes and the amount of compensation awarded in public hospitals in the Gansu Province increased annually from 2014 to 2019, with most of the disputes occurring in secondary and tertiary hospitals. Approximately 89.01% of the medical disputes were handled by TPM; the average compensation amount with TPM was Chinese Yuan (CNY) 48,688.73, significantly less than that awarded via court judgment and judicial mediation. TPM was more likely to succeed in settling medical disputes in the < CNY10,000 compensation group than in the no-compensation group (odds ratio [OR] = 3.14, 95% confidence interval [CI] 1.53-6.45). However, as the compensation amount increased, the likelihood of choosing TPM decreased significantly. Moreover, TPM was less likely to be chosen when medical disputes did not involve death (OR = 0.49, 95% CI 0.36-0.45) or when no-fault liability was determined (vs. medical accidents; OR = 0.37, 95% CI 0.20-0.67). CONCLUSION: Our findings demonstrate that TPM mechanisms play a positive role in efficiently reducing compensation amounts and increasing medical dispute resolution rates which was the main settlement method in resolving medical disputes in public hospitals of Gansu Province in China. TPM could help greatly reduce conflicts between doctors and patients, avoid litigation, and save time and costs for both parties. Moreover, compensation amounts, non-fatal outcomes, and no-fault liability determinations influence the choice of TPM for settling medical disputes.


Assuntos
Dissidências e Disputas , Hospitais Públicos , Negociação , Humanos , Hospitais Públicos/estatística & dados numéricos , China , Masculino , Feminino
4.
Psychol Health Med ; 29(3): 492-504, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36916209

RESUMO

As the mainstay of healthcare, the job satisfaction of medical staff deserves attention. This study aimed to explore the correlation between the perception of the high-performance work system (P-HPWS) and job satisfaction of medical staff in public hospitals and to further investigate the mediating effect of self-efficacy. From November 2019 to January 2020, a cross-sectional survey on working doctors and nurses was conducted in five tertiary public hospitals in China. A total of 520 participants were surveyed. The P-HPWS, job satisfaction, and self-efficacy were assessed using the 25-item self-administered scale, six-item job satisfaction questionnaire, and the General Self-Efficacy Scale, respectively. Linear regression and mediation effects models were used to identify the associations between primary variables. The results showed a significant positive correlation between P-HPWS and job satisfaction (P < 0.01), while self-efficacy played a mediating role between P-HPWS and job satisfaction. This finding reveals the benefits of improving employees' P-HPWS and self-efficacy on their job satisfaction, and that hospitals can improve their management systems by implementing and refining HPWS.


Assuntos
Atenção à Saúde , Autoeficácia , Humanos , Estudos Transversais , Inquéritos e Questionários , Corpo Clínico , Hospitais Públicos , Satisfação no Emprego
5.
Artigo em Inglês | MEDLINE | ID: mdl-37499852

RESUMO

OBJECTIVE: To determine the effectiveness of non-pharmacologic interventions and the additional benefits of their combination in patients with heart failure with reduced ejection fraction (HFrEF). DATA SOURCES: We searched PubMed, Embase, and the Cochrane Clinical Trials Register from the date of database inception to April 22, 2023. STUDY SELECTION: Randomized controlled trials involving non-pharmacologic interventions conducted in patients with HFrEF were included. DATA EXTRACTION: Data were extracted by 2 independent reviewers based on a pre-tested data extraction form. The quality of evidence was assessed using the Cochrane Risk of Bias tool and the Grading of Recommendations Assessment, Development, and Evaluation method. DATA SYNTHESIS: A total of 82 eligible studies (4574 participants) were included. We performed a random-effects model within a Bayesian framework to calculate weighted mean differences (WMDs) and 95% credibility intervals. High or moderate certainty evidence indicated that high-intensity aerobic interval training (HIAIT) was best on improving 6-minute walk distance (6MWD; 68.55 m [36.41, 100.47]) and left ventricular ejection fraction (6.28% [3.88, 8.77]), while high-intensity aerobic continuous training (HIACT) is best on improving peak oxygen consumption (Peak VO2; 3.48 mL/kg•min [2.84, 4.12]), quality of life (QOL; -17.26 [-29.99, -7.80]), resting heart rate (-8.20 bpm [-13.32, -3.05]), and N-terminal pro-B-type natriuretic peptide (-600.96 pg/mL [-902.93, -404.52]). Moderate certainty evidence supported the effectiveness of inspiratory muscle training to improve peak oxygen consumption and functional electrical stimulation to improve QOL. Moderate-intensity aerobic continuous training (MIACT) plus moderate-intensity resistance training (MIRT) had additional benefits in Peak VO2, 6MWD, and QOL. This review did not provide a comprehensive evaluation of adverse events. CONCLUSIONS: Both HIAIT and HIACT are the most effective single non-pharmacologic interventions for HFrEF. MIACT plus MIRT had additional benefits in improving peak oxygen consumption, 6MWD, and QOL.

6.
Geriatr Nurs ; 47: 71-80, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35850034

RESUMO

OBJECTIVE: To determine the most effective non-pharmacological interventions to control the blood pressure variation in older hypertensive patients. METHODS: Primary endpoints were office systolic blood pressure (SBP) and diastolic blood pressure (DBP). The quality of evidence was assessed using the "risk of bias 2″ tool and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method. We performed a Bayesian network meta-analysis using R-4.0.2 software to compare the efficacy of interventions. RESULTS: 36 eligible studies (3,531 patients) with a median follow-up of 12 weeks, assessing 18 non-pharmacological interventions, were included. The percentages of high, moderate, low, and very low certainty evidence were 16.7%, 38.9%, 33.3%, and 11.1%, respectively. CONCLUSION: High certainty evidence suggests that self-management education is most effective in lowering SBP and DBP in older patients with hypertension, followed by moderate-intensity aerobic exercise. Moderate-intensity resistance training is the most effective exercise for lowering SBP. REGISTRATION: PROSPERO, #CRD42020209850.


Assuntos
Hipertensão , Idoso , Teorema de Bayes , Pressão Sanguínea/fisiologia , Exercício Físico , Humanos , Hipertensão/terapia , Metanálise em Rede
7.
BMC Ophthalmol ; 20(1): 256, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600279

RESUMO

BACKGROUND: To describe the clinical characteristics and analyze the predictive factors associated with improved visual acuity of 359 patients with infectious endophthalmitis. METHODS: This study retrospectively analyzed 359 eyes of 359 patients with infectious endophthalmitis from January 2014 to December 2018. The findings summarized some epidemiological characteristics of these patients, including age, sex, occupation, patient visit time, etiology, causative organisms, therapy, and best-corrected visual acuity. Multivariate logistic regression was performed to predict the relative factors of improved visual acuity (VA). RESULTS: Overall, 283 (78.83%) patients were male. The mean age was 48.0 ± 18.27 years. Ocular trauma, especially open globe injuries (246, 68.5%) was the most common etiology of infectious endophthalmitis in this study. The etiologies of infectious endophthalmitis were open globe injuries (68.5%), intraocular surgery (22.6%), and corneal ulcer-associated (6.7%) and endogenous causes (2.2%). In the etiology classification and visual acuity improvement group, had statistically significant differences in factors such as age, sex, patient visit time, pre-therapy visual acuity, etc. The average Logarithm of the Minimum Angle of Resolution (logMAR) best-corrected visual acuity on pre-therapy was 2.28 ± 0.60, and it had significantly improved to 1.67 ± 0.83 post-therapy (P < 0.05). Logistic regression analysis showed that visit time > 7 day (P = 0.034, OR = 0.522, 95% CI: 0.286-0.953), pre-therapy VA ≦logMAR 2.3 (P = 0.032, OR = 1.809, 95% CI: 1.052-3.110), post-surgical (vs. posttraumatic; P = 0.023, OR = 2.100, 95% CI: 1.109-3.974), and corneal ulcer-associated etiologies (vs. posttraumatic; P = 0.005, OR = 0.202, 95%CI: 0.066-0.621) were significantly associated with improved visual acuity after adjusting for possible confounding factors. CONCLUSIONS: Among the patients with infectious endophthalmitis, middle-aged male, especially farmers and workers, accounted for a large proportion. Open globe injuries were the main cause and the gram-positive bacteria were the major causative organisms. The final visual outcomes seemed to vary according to the type of endophthalmitis, but early treatment and good initial visual acuity were important factors for visual acuity improvement.


Assuntos
Úlcera da Córnea , Endoftalmite , Infecções Oculares Bacterianas , Ferimentos Oculares Penetrantes , Adulto , Idoso , Endoftalmite/epidemiologia , Endoftalmite/terapia , Infecções Oculares Bacterianas/epidemiologia , Infecções Oculares Bacterianas/terapia , Ferimentos Oculares Penetrantes/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acuidade Visual , Vitrectomia
8.
Hepatology ; 67(1): 56-70, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28749559

RESUMO

Covalently closed circular DNA of hepatitis B virus (HBV) is critical for viral persistence in vivo. We recently reported a technique involving recombinant covalently closed circular DNA (rcccDNA) of HBV by site-specific DNA recombination. Using hydrodynamic injection, rcccDNA induces a temporarily prolonged HBV antigenemia in immunocompetent mice, similar to acute resolving HBV infection. In this study, we simulated the pathophysiological impact of chronic hepatitis to reproduce rcccDNA persistence in mouse models. We showed that rcccDNA achieved long-lasting persistence in the presence of a compromised immune response or when transcriptional activity was repressed. To closely mimic chronic hepatitis, we used a replication-defective recombinant adenoviral vector to deliver rcccDNA to the liver, which led to prominent HBV persistence throughout the experiment duration (>62 weeks) in transgenic mice expressing Cre recombinase under the albumin promoter. A sustained necroinflammatory response and fibrosis were identified in mouse livers, with dysplastic lesions commonly seen during the late stage of viral persistence, analogous to the progressive pathology of clinical chronic hepatitis. CONCLUSION: rcccDNA was intrinsically stable in vivo, enabling long-term persistence in the context of chronic hepatitis, and viral persistence, in turn, may promote progression of chronic liver disease; our study also presented a surrogate model of HBV cccDNA persistence in mice that could advance our understanding of the pathogenesis of chronic hepatitis B. (Hepatology 2018;67:56-70).


Assuntos
Replicação do DNA/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/patologia , Replicação Viral/genética , Animais , Biópsia por Agulha , DNA Circular/genética , DNA Recombinante/genética , DNA Viral , Modelos Animais de Doenças , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
9.
Molecules ; 24(10)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31137603

RESUMO

Agarwood is the resinous wood produced in some Aquilaria species and is highly valued for wide usages in medicine, incense, and perfume. To protect the threatened Aquilaria species, the cultivation of Aquilaria sinensis and artificial agarwood induction techniques have been effectively established in China. To evaluate the quality of agarwood induced by different techniques, patterns of chemical constituents in artificial agarwood by four methods (wounding using an axe, burning-chisel-drilling, chemical inducer, and biological inoculation) were analyzed and compared by UPLC-ESI-MS/MS and GC-EI-MS in this study. Results of GC-MS gave a panorama of chemical constituents in agarwood, including aromatic compounds, steroids, fatty acids, sesquiterpenoids, and 2-(2-phenlyethyl)-chromones (PECs). Sesquiterpenoids were dominant in agarwood induced by wounding using an axe. PEC comprised over 60% of components in agarwood produced by biological inoculation and chemical inducers. PECs were identified by UPLC-ESI-MS/MS in all artificial agarwood and the relative contents varied in different groups. Tetrahydro-2-(2-phenylethyl)-chromones (THPECs) in wounding by axes induced agarwood were lower while 2-(2-phenylethyl)-chromones (FPECs) were higher than other groups. The results showed that methods used for inducing agarwood formation in Aquilaria sinensis affect the chemical constituents of agarwood.


Assuntos
Thymelaeaceae/química , Madeira/química , Madeira/crescimento & desenvolvimento , Algoritmos , Flavonoides/química , Cromatografia Gasosa-Espectrometria de Massas , Análise Multivariada , Análise de Componente Principal
10.
J Virol ; 89(4): 2041-51, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25428880

RESUMO

UNLABELLED: Hepatitis B, which caused by hepatitis B virus (HBV) infection, remains a major health threat worldwide. Hepatic injury and regeneration from chronic inflammation are the main driving factors of liver fibrosis and cirrhosis in chronic hepatitis B. Proinflammatory tumor necrosis factor alpha (TNF-α) has been implicated as a major inducer of liver cell death during viral hepatitis. Here, we report that in hepatoma cell lines and in primary mouse and human hepatocytes, expression of hepatitis B virus core (HBc) protein made cells susceptible to TNF-α-induced apoptosis. We found by tandem affinity purification and mass spectrometry that receptor of activated protein kinase C 1 (RACK1) interacted with HBc. RACK1 was recently reported as a scaffold protein that facilitates the phosphorylation of mitogen-activated protein kinase kinase 7 (MKK7) by its upstream activators. Our study showed that HBc abrogated the interaction between MKK7 and RACK1 by competitively binding to RACK1, thereby downregulating TNF-α-induced phosphorylation of MKK7 and the activation of c-Jun N-terminal kinase (JNK). In line with this finding, specific knockdown of MKK7 increased the sensitivity of hepatocytes to TNF-α-induced apoptosis, while overexpression of RACK1 counteracted the proapoptotic activity of HBc. Capsid particle formation was not obligatory for HBc proapoptotic activity, as analyzed using an assembly-defective HBc mutant. In conclusion, the expression of HBc sensitized hepatocytes to TNF-α-induced apoptosis by disrupting the interaction between MKK7 and RACK1. Our study is thus the first indication of the pathogenic effects of HBc in liver injury during hepatitis B. IMPORTANCE: Our study revealed a previously unappreciated role of HBc in TNF-α-mediated apoptosis. The proapoptotic activity of HBc is important for understanding hepatitis B pathogenesis. In particular, HBV variants associated with severe hepatitis may upregulate apoptosis of hepatocytes through enhanced HBc expression. Our study also found that MKK7 is centrally involved in TNF-α-induced hepatocyte apoptosis and revealed a multifaceted role for JNK signaling in this process.


Assuntos
Apoptose , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , Hepatócitos/virologia , Interações Hospedeiro-Patógeno , Fator de Necrose Tumoral alfa/imunologia , Animais , Células Cultivadas , Proteínas de Ligação ao GTP/metabolismo , Hepatócitos/fisiologia , Humanos , MAP Quinase Quinase 7/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Receptores de Quinase C Ativada , Receptores de Superfície Celular/metabolismo
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 55-9, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-27228740

RESUMO

The biomass to plastic ratio in wood plastic composites (WPCs) greatly affects the physical and mechanical properties and price. Fast and accurate evaluation of the biomass to plastic ratio is important for the further development of WPCs. Quantitative analysis of the WPC main composition currently relies primarily on thermo-analytical methods. However, these methods have some inherent disadvantages, including time-consuming, high analytical errors and sophisticated, which severely limits the applications of these techniques. Therefore, in this study, Fourier Transform Infrared (FTIR) spectroscopy in combination with partial least square (PLS) has been used for rapid prediction of bamboo and polypropylene (PP) content in bamboo/PP composites. The bamboo powders were used as filler after being dried at 105 degrees C for 24 h. PP was used as matrix materials, and some chemical regents were used as additives. Then 42 WPC samples with different ratios of bamboo and PP were prepared by the methods of extrusion. FTIR spectral data of 42 WPC samples were collected by means of KBr pellets technique. The model for bamboo and PP content prediction was developed by PLS-2 and full cross validation. Results of internal cross validation showed that the first derivative spectra in the range of 1 800-800 cm(-1) corrected by standard normal variate (SNV) yielded the optimal model. For both bamboo and PP calibration, the coefficients of determination (R2) were 0.955. The standard errors of calibration (SEC) were 1.872 for bamboo content and 1.848 for PP content, respectively. For both bamboo and PP validation, the R2 values were 0.950. The standard errors of cross validation (SECV) were 1.927 for bamboo content and 1.950 for PP content, respectively. And the ratios of performance to deviation (RPD) were 4.45 for both biomass and PP examinations. The results of external validation showed that the relative prediction deviations for both biomass and PP contents were lower than ± 6%. FTIR combined with PLS can be used for rapid and accurate determination of bamboo and PP content in bamboo/PP composites.

12.
J Virol ; 88(14): 8045-56, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24807718

RESUMO

It remains crucial to develop a laboratory model for studying hepatitis B virus (HBV) chronic infection. We hereby produced a recombinant covalently closed circular DNA (rcccDNA) in view of the key role of cccDNA in HBV persistence. A loxP-chimeric intron was engineered into a monomeric HBV genome in a precursor plasmid (prcccDNA), which was excised using Cre/loxP-mediated DNA recombination into a 3.3-kb rcccDNA in the nuclei of hepatocytes. The chimeric intron was spliced from RNA transcripts without interrupting the HBV life cycle. In cultured hepatoma cells, cotransfection of prcccDNA and pCMV-Cre (encoding Cre recombinase) resulted in accumulation of nuclear rcccDNA that was heat stable and epigenetically organized as a minichromosome. A mouse model of HBV infection was developed by hydrodynamic injection of prcccDNA. In the presence of Cre recombinase, rcccDNA was induced in the mouse liver with effective viral replication and expression, triggering a compromised T-cell response against HBV. Significant T-cell hyporesponsiveness occurred in mice receiving 4 µg prcccDNA, resulting in prolonged HBV antigenemia for up to 9 weeks. Persistent liver injury was observed as elevated alanine transaminase activity in serum and sustained inflammatory infiltration in the liver. Although a T-cell dysfunction was induced similarly, mice injected with a plasmid containing a linear HBV replicon showed rapid viral clearance within 2 weeks. Collectively, our study provides an innovative approach for producing a cccDNA surrogate that established HBV persistence in immunocompetent mice. It also represents a useful model system in vitro and in vivo for evaluating antiviral treatments against HBV cccDNA. Importance: (i) Unlike plasmids that contain a linear HBV replicon, rcccDNA established HBV persistence with sustained liver injury in immunocompetent mice. This method could be a prototype for developing a mouse model of chronic HBV infection. (ii) An exogenous intron was engineered into the HBV genome for functionally seamless DNA recombination. This original approach could be also extended to other viral studies. (iii) rcccDNA was substantially induced in the nuclei of hepatocytes and could be easily distinguished by its exogenous intron using PCR. This convenient model system affords the opportunity to test antivirals directly targeting HBV cccDNA.


Assuntos
DNA Circular/genética , DNA Viral/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/genética , Alanina Transaminase/sangue , Animais , Núcleo Celular/virologia , Células Cultivadas , Modelos Animais de Doenças , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Hepatócitos/virologia , Humanos , Fígado/patologia , Camundongos , Camundongos Transgênicos
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1546-50, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26601364

RESUMO

The ratio of wood and plastic in Wood Plastic Composites (WPCss) influences quality and price, but traditional thermochemical methods cannot rapidly and accurately quantify the ratio of wood/PP in WPCss. This paper was addressed to investigate the feasibility of quantifying the wood flour content and plastic content in WPCss by Fourier Transform Infrared (FTIR) spectroscopy. With Chinese fir, polypropylene (PP) and other additives as raw materials, 13 WPCs samples with different wood flour contents, ranging from 9.8% to 61.5%, were prepared by modifying wood flour, mixing materials and extrusion pelletizing. The samples were analyzed by FTIR with the KBr pellets technique. The absorption peaks of WPCss at 1059, 1 033 and 1 740 cm(-1) are considered as characteristic of Chinese fir, and the absorption peaks at 1 377, 2 839 and 841 cm(-1) are typical of PP by comparing the spectra of WPCss with that of Chinese fir, PP and other additives. The relationship between the wood flour content, PP content in WPCss and their characteristic IR peaks height ratio was established. The results show that there is a strong linear correlation between the wood flour content in WPCss and I1 059/l 1 377/I1 033, /I1377, R2 are 0.992 and 0.993 respectively; there is a high linear correlation between the PP content in WPCss and I1 377/I1 740, I2 839 /I1 740 R2 are 0.985 and 0.981, respectively. Quantitative methods of the wood flour content and PP content in WPCss by FTIR were developed, the predictive equations of the wood flour content in WPCss are y = 53.297x-9. 107 and y = 55.922x-10.238, the predictive equations of the PP content in WPCss are y = 6.828 5x+5.403 6 and y = 8.719 7x+3.295 8. The results of the accuracy test and precision test show that the method has strong repeatability and high accuracy. The average prediction relative deviations of the wood flour content and PP content in WPCss are about 5%. The prediction accuracy has been improved remarkably, compared to thermochemical methods. More importantly, FTIR is more easy-handing. This experiment may provide a simple, rapid and accurate method for quantification of wood flour and PP in Chinese fir/PP composites.

14.
J Biol Chem ; 288(3): 1785-94, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23212909

RESUMO

Arkadia is a RING-based ubiquitin ligase that positively regulates TGF-ß signaling by targeting several pathway components for ubiquitination and degradation. However, little is known about the mechanisms controlling Arkadia activity. Here we show that the LIM-only protein FHL2 binds and synergistically cooperates with Arkadia to activate Smad3/Smad4-dependent transcription. Knockdown of FHL2 by RNA interference decreases Arkadia level and restricts the amplitude of Arkadia-induced TGF-ß target gene responses. We found that Arkadia is ubiquitinated via K63- and K27-linked polyubiquitination. A single mutation at the RING domain that abolishes the E3 activity diminishes Arkadia ubiquitination, indicating that this modification partly involves autocatalytic process. Mutation of seven lysines at the C-terminal region of Arkadia severely impairs ubiquitination through the K27 but not the K63 linkage and slows down the turnover of Arkadia, suggesting that K27-linked polyubiquitination might promote proteolysis-dependent regulation of Arkadia. We show that FHL2 increases the half-life of Arkadia through inhibition of ubiquitin chain assembly on the protein, which provides a molecular basis for functional cooperation between Arkadia and FHL2 in enhancing TGF-ß signaling. Our study uncovers a novel regulatory mechanism of Arkadia by ubiquitination and identifies FHL2 as important regulator of Arkadia ubiquitination and TGF-ß signal transduction.


Assuntos
Proteínas com Homeodomínio LIM/genética , Proteínas Musculares/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina/genética , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Meia-Vida , Humanos , Proteínas com Homeodomínio LIM/metabolismo , Luciferases , Camundongos , Proteínas Musculares/metabolismo , Mutação , Proteínas Nucleares/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transfecção , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
15.
Fitoterapia ; 176: 106012, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38744381

RESUMO

One of the primary applications for agarwood lies in the extracts, instead, there are obvious differences in the demands for agarwood components with different application fields. To obtain the rough separation and clarify each part's activity, four extracts of essential oil, hydrolat, extractum, and ethanol precipitation from traditional agarwood (TraA) and "Qinan" agarwood (QinA) were obtained by steam-solvent multistage extraction and ethanol precipitation. We investigated the chemistry and biological activity of multistage extracts using gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC), and in vitro activity testing. The results demonstrated that two kinds of agarwood essential oils contained mainly sesquiterpenoids, yet the sesquiterpene species were remarkably diverse in two kinds of agarwood essential oils. Then, the TraA and QinA hydrolat, all predominantly aromatic and sesquiterpene, but with differences from the essential oil ingredients. Additionally, the extractum chiefly contained chromones and the ethanol precipitation method worked well to separate the impurities in the TraA extract, however, it was ineffective for the QinA extract. Ultimately, essential oils and extractums all have antioxidant properties, with extractums outperforming essential oils. Moreover, both extractums and essential oils exhibited excellent broad-spectrum antimicrobial activity and anti-inflammatory activity. The findings pointed to the feasibility of separating the primary components from TraA and QinA using a multi-stage extraction technique, providing a scientific basis for the efficient utilization of all components of agarwood, as well as the functional product development and differentiated utilization of extract products in incense, fragrance, perfume, and daily chemicals.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis , Extratos Vegetais , Sesquiterpenos , Thymelaeaceae , Thymelaeaceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/química , Madeira/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/química , Cromonas/isolamento & purificação , Cromonas/farmacologia , Cromonas/química
16.
Int J Biol Macromol ; 254(Pt 3): 127948, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951432

RESUMO

Colloidal lignin particles (CLPs) have sparked various intriguing insights toward bio-polymeric materials and triggered many lignin-featured innovative applications. Here, we report a multi-solvent sequential fractionation methodology integrating green solvents of acetone, 1-butanol, and ethanol to fractionate industrial lignin for CLPs fabrication. Through a rationally designed fractionation strategy, multigrade lignin fractions with variable hydroxyl group contents, molecular weights, and high purity were obtained without altering their original chemical structures. CLPs with well-defined morphology, narrow size distribution, excellent thermal stability, and long-term colloidal stability can be obtained by rational selection of lignin fractions. We further elucidated that trace elements (S, N) were reorganized onto the near-surface area of CLPs from lignin fractions during the formation process in the form of -SO42- and -NH2. This work provides a sustainable and efficient strategy for refining industrial lignin into high-quality fractions and an in-depth insight into the CLPs formation process, holding great promise for enriching the existing libraries of colloidal materials.


Assuntos
Etanol , Lignina , Solventes/química , Lignina/química , Acetona , Fracionamento Químico/métodos
17.
Fitoterapia ; 175: 105901, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38467281

RESUMO

To compare the bioactive compounds in agarwood induced by different methods in Aquilaria sinensis(Lour.) Gilg trees, a two dimensional thin layer chromatograph(2D-TLC) combined with effect directive analysis(EDA) was developed. Three antioxidants were found by 2D-TLC-DPPH and further identified as 2-(2-phenylethyl) chromones(PECs) with LC-MS/MS. The 3 antioxidants decreased along agarwood formation and their compositions in drilling induced agarwood differed with those in microbe culture induced agarwood. Further study showed NaCl treatment promoted antioxidants accumulation in agarwood induced by drilling or hot drilling. Hot drilling combined with salty stimulation was most efficient in some chemicals accumulation, which were identified as PECs with antioxidant, tyrosinase or ß-glucosidase inhibiting activities by 2D-TLC-EDA-LC-MS/MS. This study provided a 2D-TLC-EDA-LC-MS/MS method for bioactive compounds screen and qualification of agarwood. Based on this method, non-conventional methods were found to accelerate the accumulation of some bioactive PECs in A. sinensis trees.


Assuntos
Antioxidantes , Espectrometria de Massas em Tandem , Thymelaeaceae , Thymelaeaceae/química , Antioxidantes/farmacologia , Cromatografia em Camada Fina , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Madeira/química , Cloreto de Sódio/farmacologia , Cloreto de Sódio/química , Cromatografia Líquida , Monofenol Mono-Oxigenase/antagonistas & inibidores , Estrutura Molecular , Flavonoides
18.
Front Plant Sci ; 15: 1320226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590741

RESUMO

Recently, some new Qi-Nan clones of Aquilaria sinensis (Lour.) Spreng which intensively produces high-quality agarwood have been identified and propagated through grafting techniques. Previous studies have primarily focused on ordinary A. sinensis and the differences in composition when compared to Qi-Nan and ordinary A. sinensis. There are few studies on the formation mechanism of Qi-Nan agarwood and the dynamic changes in components and endophytic fungi during the induction process. In this paper, the characteristics, chemical composition, and changes in endophytic fungi of Qi-Nan agarwood induced after 1 year, 2 years, and 3 years were studied, and Qi-Nan white wood was used as the control. The results showed that the yield of Qi-Nan agarwood continued to increase with the induction time over a period of 3 years, while the content of alcohol extract from Qi-Nan agarwood reached its peak at two years. During the formation of agarwood, starch and soluble sugars in xylem rays and interxylary phloem are consumed and reduced. Most of the oily substances in agarwood were filled in xylem ray cells and interxylary phloem, and a small amount was filled in xylem vessels. The main components of Qi-Nan agarwood are also chromones and sesquiterpenes. With an increasing induction time, the content of sesquiterpenes increased, while the content of chromones decreased. The most abundant chromones in Qi-Nan agarwood were 2-(2-Phenethyl) chromone, 2-[2-(3-Methoxy-4-hydroxyphenyl) ethyl] chromone, and2-[2-(4-Methoxyphenyl) ethyl] chromone. Significant differences were observed in the species of the endophytic fungi found in Qi-Nan agarwood at different induction times. A total of 4 phyla, 73 orders, and 448 genera were found in Qi-Nan agarwood dominated by Ascomycota and Basidiomycota. Different induction times had a significant effect on the diversity of the endophytic fungal community in Qi-Nan. After the induction of agarwood formation, the diversity of Qi-Nan endophytic fungi decreased. Correlation analysis showed that there was a significant positive correlation between endophytic fungi and the yield, alcohol extract content, sesquiterpene content, and chromone content of Qi-Nan agarwood, which indicated that endophytic fungi play a role in promoting the formation of Qi-Nan agarwood. Qi-Nan agarwood produced at different induction times exhibited strong antioxidant capacity. DPPH free radical scavenging activity and reactive oxygen species clearance activity were significantly positively correlated with the content of sesquiterpenes and chromones in Qi-Nan agarwood.

19.
J Healthc Eng ; 2023: 5816473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844949

RESUMO

Objective: To investigate anatomical and visual outcomes of macular hole (MH) after inverted internal limiting membrane (ILM) flap technique for idiopathic macular hole (IMH). Methods: A total of 13 IMH cases diagnosed in Shanxi Eye Hospital between January 2015 and June 2016 were included in the study. All patients underwent vitrectomy combined with indocyanine green-assisted inverted ILM flap technique. The MH closure rate, best-corrected visual acuity (BCVA), changes of ellipsoid zone (EZ), and external limiting membrane (ELM) were examined before operation and one, three, and six months after operation. Furthermore, 488 nm fundus autofluorescence (FAF) and spectral domain optical coherence tomography (SD-OCT) were used to observe the dynamic changes in function of macular area after surgery. Results: One month after the surgery, the MH closure rate was 100% and the visual acuity (VA) was stable, with no recurrence. Additionally, the average logMAR BCVA before operation was 1.208 ± 0.158, and this value became 0.877 ± 0.105 one month after the operation, showing a significant decrease. Three months after surgery, the average logMAR BCVA was 0.792 ± 0.103, which was significantly lower than the level one month after the surgery but much higher than that six months after surgery (0.708 ± 0.131). Besides, the diameter of the EZ defect of the postoperative one month, three months, and six months was (1377.46 ± 198.65) µm, (964.62 ± 336.26) µm, and (817.08 ± 442.99) µm, respectively. In postoperative one month, three months, and six months, the diameter of the ELM defect diameter was (969.62 ± 189.92) µm, (649.92 ± 413.15) µm, and (557.62 ± 412.50) µm, respectively. The diameter of both EZ and ELM defects was significantly reduced with the passage of time after surgery. Conclusion: Inverted ILM flap technique can reconstruct macular anatomical structure and improve VA. This technique is effective for the treatment of IMH with large MH minimum diameter and base diameter.


Assuntos
Perfurações Retinianas , Humanos , Perfurações Retinianas/cirurgia , Perfurações Retinianas/diagnóstico , Estudos Retrospectivos , Retina/diagnóstico por imagem , Retina/cirurgia , Acuidade Visual , Retalhos Cirúrgicos
20.
Exp Ther Med ; 21(4): 332, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33732305

RESUMO

The present study aimed to investigate the mechanisms of anti-VEGF treatment prior to eye surgery to reduce intraoperative bleeding. A total of 30 patients with proliferative vitreoretinopathy after clinical diagnosis were enrolled in the present study as the surgical group. Furthermore, 30 patients underwent intravitreal injection of the anti-VEGF drug conbercept and were considered the drug pretreatment group. The aqueous and vitreous humors from the eyes of patients in the surgical group were drawn during pars plana vitrectomy surgery. The aqueous humor in the eyes of patients in the drug pretreatment group was drawn prior to conbercept treatment and seven days after conbercept treatment immediately prior to surgery. The vitreous humor in this group was only taken during surgery. Furthermore, ELISA was used to detect the levels of VEGF-A and -B in the aqueous and vitreous humors. Semi-quantitative determination of VEGF-A and VEGF-B levels in fibrovascular proliferative membranes was performed using immunohistochemical staining. The results indicated that in the drug group, the levels of VEGF-A in the aqueous humor of patients prior to and after conbercept injection were 197.66±48.00 and 3.39±2.54 pg/ml, respectively. The levels of VEGF-A in the vitreous humor of patients in the surgical and drug groups were 267.53±179.60 and 21.43±5.81 pg/ml after injection, respectively. The levels of VEGF-B in the aqueous humor of patients prior to and after conbercept injection were 13.66±3.30 (before injection) and 2.17±0.94 pg/ml (after injection), respectively. The levels of VEGF-B in the vitreous humor of patients in the surgical and drug groups were 127.36±16.72 and 18.56±9.82 pg/ml after injection, respectively (P<0.05). Furthermore, in the drug group, the surgery time, bleeding and capillary formation were significantly reduced compared with those in the surgical group. Taken together, these results suggested that the levels of VEGF-A and -B decreased significantly in the aqueous humor of patients with PDR after conbercept injection. Furthermore, the levels of VEGF-A and -B in the vitreous humor of patients dropped significantly in the drug group compared with those in the surgical group. These results provide theoretical clinical support for the preoperative application of conbercept for patients with PDR.

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