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1.
Sci Rep ; 13(1): 14744, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679399

RESUMO

Patients narratives are being recorded increasingly frequently and spontaneously in short user produced content (UGC) films, which may have an impact on the vlogger's health as well as the public's comprehension of the relevant health concerns. This paper addressed three research questions regarding the population characteristics of UGC video publishers, the narrative theme of the videos, and the emotional orientation of the commenters. This study aimed to deepen our understanding of COVID-19 patients' narrative intentions and emotional needs through the theoretical frameworks of theory of planned behavior (TPB) and negative dominance theory (NDT). We collected 335 videos from 28 COVID-19 patients and 572,052 comments as samples on Douyin platform, the largest short-video website in China. Using Latent Semantic Analysis, we analyzed the descriptive information of the video blogs, the narrative textual information of the videos, and the emotional orientation of the comments. Our findings revealled seven categories of narrative themes, with 52.1% of video comments exhibiting a positive emotional orientation. Within a framework integrating TPB and NDT theories, we analyzed the behavioral intentions of vloggers and viewers during COVID-19 epidemic, and interpreted the persistent posting of videos and the active posting of comments as positive actions that counteracted the multiple effects of negative messages. This study contributes to the understanding of individual narratives in macro-risk communication, both theoretically and empirically, and offers policy recommendations in relevant fields.


Assuntos
COVID-19 , Humanos , Narração , Comunicação , Blogging , China/epidemiologia
2.
Lasers Med Sci ; 37(3): 1605-1614, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34480664

RESUMO

It had been suggested, after facilitating the hatching process, improved pregnancy outcomes could be attained in embryos with thick and hard zona. This study aimed to determine the effect of zona thinning on pregnancy outcomes in poor-quality frozen-thawed blastocysts. This retrospective study included 230 women (≤ 40 years) who underwent frozen embryo transfer of poor-quality blastocysts (scored < 3BB). In total, 105 patients were in the assisted hatching group in which the zona was thinned by laser before transfer and 125 patients were in the control group in which the blastocysts were non-manipulated. Patients' demographics, cycle characteristics, and pregnancy outcomes were compared between the assisted hatching group and the control group. Further, regression analysis was applied to test the correlation between assisted hatching and live birth. All parameters in the patients' demographic characteristics and the cycle's characteristics were not significantly different between two groups. As for pregnancy outcomes, the second trimester pregnancy loss was significantly higher in the assisted hatching group (P = 0.035). Other pregnancy outcomes, including implantation rate, clinical pregnancy rate, biochemical miscarriage rate, the first trimester pregnancy loss, ongoing pregnancy rate, and live birth rate were comparable between two groups. The logistic regression analysis demonstrated no association between live birth and assisted hatching (univariate, OR = 0.787, P > 0.05; multivariate, OR = 0.652, P > 0.05), and the area under the receiver operating characteristic curve of the regression model was almost 0.7. It suggested that zona thinning may not be supposed to perform on poor-quality, frozen-thawed blastocysts. The indications of assisted hatching were still needed to further investigate.


Assuntos
Criopreservação , Resultado da Gravidez , Blastocisto , Transferência Embrionária , Feminino , Humanos , Lasers , Gravidez , Estudos Retrospectivos
3.
Front Endocrinol (Lausanne) ; 12: 686054, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248847

RESUMO

Background: rs13405728 was identified as one of the most prevalent susceptibility loci for polycystic ovary syndrome (PCOS) in Han Chinese and Caucasian women. However, the target genes and potential mechanisms of the rs13405728 locus remain to be determined. Methods: Three-dimensional (3D) genome interactions from the ovary tissue were characterized via high-through chromosome conformation capture (Hi-C) and Capture Hi-C technologies to identify putative targets at the rs13405728 locus. Combined analyses of eQTL, RNA-Seq, DNase-Seq, ChIP-Seq, and sing-cell sequencing were performed to explore the molecular roles of these target genes in PCOS. PCOS-like mice were applied to verify the expression patterns. Results: Generally, STON1 and FSHR were identified as potential targets of the rs13405728 locus in 3D genomic interactions with epigenomic regulatory peaks, with STON1 (P=0.0423) and FSHR (P=0.0013) being highly expressed in PCOS patients. STON1 co-expressed genes were associated with metabolic processes (P=0.0008) in adipocytes (P=0.0001), which was validated in the fat tissue (P<0.0001) and ovary (P=0.0035) from fat-diet mice. The immune system process (GO:0002376) was enriched in FSHR co-expressed genes (P=0.0002) and PCOS patients (P=0.0002), with CD4 high expression in PCOS patients (P=0.0316) and PCOS-like models (P=0.0079). Meanwhile, FSHR expression was positively correlated with CD4 expression in PCOS patients (P=0.0252) and PCOS-like models (P=0.0178). Furthermore, androgen receptor (AR) was identified as the common transcription factor for STON1 and FSHR and positively correlated with the expression of STON1 (P=0.039) and FSHR (P=4e-06) in ovary tissues and PCOS-like mice. Conclusion: Overall, we identified STON1 and FSHR as potential targets for the rs13405728 locus and their roles in the processes of adipocyte metabolism and CD4 immune expression in PCOS, which provides 3D genomic insight into the pathogenesis of PCOS.


Assuntos
Proteínas de Membrana/genética , Síndrome do Ovário Policístico/genética , Receptores do FSH/genética , Fatores Genéricos de Transcrição/genética , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Antígenos CD4/imunologia , Feminino , Expressão Gênica , Loci Gênicos , Genoma , Humanos , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Ovário/metabolismo , Síndrome do Ovário Policístico/imunologia , Síndrome do Ovário Policístico/metabolismo , Receptores Androgênicos/genética , Receptores do FSH/imunologia , Fatores Genéricos de Transcrição/metabolismo
4.
Int J Biol Sci ; 17(7): 1744-1756, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994859

RESUMO

Human papillomavirus (HPV) infection and gene mutations were reputed as key factors in cervical carcinoma (CC) and head and neck squamous cell carcinoma (HNSCC). However, the associations of HPV status and gene mutations remain to be determined. This study aims to identify molecular patterns of LRP1B mutation and HPV status via rewiring tumor samples of HNSCC (n=1478) and CC (n=178) from the TCGA dataset. Here, we found that LRP1B mutation was associated with HPV status in CC (P=0.040) and HNSCC (P=0.044), especially in HPV 16 integrated CC (P=0.036). Cancer survival analysis demonstrated that samples with LRP1B mutation showed poor disease outcomes in CC (P=0.013) and HNSCC (P=0.0124). In addition, the expression status of LPR1B was more favorable for prediction than TP53 or RB1 in CC and HNSCC. Mutation clustering analysis showed that samples with LRP1B mutation showed higher mutation count in CC (P=1.76e-67) and HNSCC (P<10e-10). Further analysis identified 289 co-occurrence genes in these two cancer types, which were enriched in PI3K signaling, cell division process, and chromosome segregation process, et al. The 289-co-occurrence gene signature identified a cluster of patients with a higher portion of copy number variation (CNV) lost in the genome, different tumor HPV status (P<10e-10), higher mutation count (P<10e-10), higher fraction genome altered value (P=2.078e-4), higher aneuploidy score (P=3.362e-4), and earlier started the smoking year (P=2.572e-4), which were associated with shorter overall survival (P=0.0103) in CC and HNSCC samples. Overall, LRP1B mutation was associated with tumor HPV status and was an unfavorable prognostic biomarker for CC and HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço/genética , Mutação , Papillomaviridae , Infecções por Papillomavirus/genética , Receptores de LDL/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias do Colo do Útero/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Feminino , Perfilação da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Receptores de LDL/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
5.
Hypertens Res ; 43(6): 511-517, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32042143

RESUMO

MicroRNAs are key molecules involved in the regulation of endothelial function. They are important risk factors and biomarkers for the development of hypertension related to endothelial dysfunction. However, the gene expression patterns associated with hypertension development related to endothelial dysfunction have not been fully elucidated. We conducted a case-control study of 65 patients with essential hypertension (EH) and 61 controls without EH. Plasma levels of miR-122 and its target protein high-affinity cationic amino acid transporter 1 (CAT-1) were measured by qRT-PCR and ELISA, respectively. miR-122 expression in plasma of patients with EH was significantly higher than that of the control group (p = 0.001), while CAT-1 expression in patients with EH was significantly lower than that in the control group (p = 0.018). miR-122 expression in plasma of young patients with EH was significantly higher than that in young people without EH (p = 0.0004), and CAT-1 expression in plasma of young patients with EH was also significantly lower than that of the control group (p = 0.002). CAT-1 expression in the plasma of young participants was significantly higher than that of individuals aged ≥40 years (p = 0.003), whereas miR-122 expression was significantly lower (p = 0.001). We showed that among patients with EH, the high expression of miR-122 contributed to endothelial dysfunction by suppressing the expression of the CAT-1 protein, which led to a decrease in CAT-1 expression in plasma. Therefore, high expression of miR-122 appears to be a risk factor for endothelial dysfunction in EH, especially in younger patients.


Assuntos
Endotélio Vascular/fisiopatologia , Hipertensão Essencial/sangue , MicroRNAs/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Hipertensão Essencial/fisiopatologia , Feminino , Proteínas Ativadoras de GTPase/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
Huan Jing Ke Xue ; 40(11): 5124-5132, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854582

RESUMO

To obtain a mild Fenton pre-oxidation method, which could promote the efficient degradation of total petroleum hydrocarbons (TPH) in subsequent bioremediation, the differences in the characteristics of the hydroxyl radical (·OH), nutrient consumption, activity of indigenous bacteria (CO2), and TPH removal were investigated during subsequent bioremediation after different Fenton pre-oxidation treatments. The results showed that high biodegradation of TPH was observed after mild Fenton pre-oxidation (·OH existence time:73 h; H2O2 concentration:225 mmol·L-1), because of the high activity of residual bacteria. Moreover, the same TPH removal with the addition of bacteria could be achieved without adding bacteria (the TPH removal rate 38%) because the activity of the residual bacteria was strong after mild Fenton pre-oxidation. Under the condition of no additional bacteria source, mild Fenton pre-oxidation TPH removal (approximately 38%) was higher than that after ordinary Fenton pre-oxidation (15.32%-33.15%). Further analysis of the removal efficiency of each chain of hydrocarbons revealed that the mild pre-oxidation group could reduce the inhibition of the chain hydrocarbon components (C17-C21) in the subsequent bioremediation stage. Comparing the activity of the indigenous bacteria in each group, revealed that mild pre-oxidation could appropriately stimulate the growth and increase the activity of indigenous microorganisms, all of which are beneficial to the removal of TPH.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Hidrocarbonetos , Peróxido de Hidrogênio , Solo , Microbiologia do Solo
7.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 34(2): 154-158, 2018 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29926681

RESUMO

OBJECTIVES: Investigate the influence of benazepril and amlodipine on the expression of secretin (PZ) and somatostatin (SS) in spontaneously hypertensive rats (SHR). METHODS: Forty-five SHRs (14 weeks old, male) were randomly assigned into 3 groups (n=15):SHR group, Benazepril group (which was given benazepril 0.90 mg·kg-1·d-1) and Amlodipine group (SHRs were given amlodipine 0.45 mg· kg-1·d-1), taking WistarKyoto(WKY) as normal control (n=15), meanwhile, rats in SHR group and WKY group were given the same volume of distilled water. After 8 weeks of intervention, the expression of protein and mRNA of PZ in duodenum and SS in sinuses ventriculi was detected by enzyme-linked immunoassay and RT-PCR. RESULTS: After 8 weeks of intervention, compared with the WKY group, the expression of protein and mRNA of PZ in duodenum and SS in sinuses ventriculi was increased significantly in SHR group (P<0. 05). Compared with SHR group, the expression of PZ in duodenum and SS in sinuses ventriculi was decreased significantly in Benazepril group and Amlodipine group (P<0.05). Compared with Benazepril group, in Amlodipine group the expression of PZ mRNA in duodenum and SS mRNA in sinuses ventriculi was decreased more significantly (P<0.05). CONCLUSIONS: The regulation disorder of PZ in duodenum and SS in sinuses ventriculi exists in SHR. The antihypertensive effect of benazepril and amlodipine may be realized by regulating the expression of PZ and SS, while the regulation of amlodipine is more obvious than benazepril.


Assuntos
Anlodipino/farmacologia , Anti-Hipertensivos/farmacologia , Benzazepinas/farmacologia , Hipertensão/tratamento farmacológico , Secretina/metabolismo , Somatostatina/metabolismo , Animais , Pressão Sanguínea , Masculino , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2879-83, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-30084619

RESUMO

The interaction between colistin sulfate (CS) with bovine serum albumin in physiological buffer (pH 7.4) was investigated with resonance light scattering spectroscopy at 298, 310, and 318 K. The analysis of data indicated that quenching mechanism of BSA-CS was probably static. The value of n was approximately 1, indicating there was only a single class of binding sites on BSA for CS compounds. The thermodynamic parameters were calculated at different temperatures, implying that the interaction was spontaneous and electrostatic force played major role in the binding between CS and BSA. The values of nH were equal to 1 at different temperatures, indicating there was non-cooperative reaction between BSA and CS. The feasibility of resonance light scattering spectroscopy was verified by fluorescence quenching spectroscopy. The quenching reactive parameters (KSV,Kq,n,Ka) from two methods were similar, suggesting resonance light scattering spectroscopy could be used to study the binding interaction between protein and drugs. Resonance light scattering spectroscopy can be used to explore the substance without intrinsic fluorescence, suggesting that the application of resonance light scattering spectroscopy broadens the understanding of the interaction between small molecules and protein.

9.
Chin J Integr Med ; 22(7): 532-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26264572

RESUMO

OBJECTIVE: To investigate the effect of direct moxibustion at Ganshu (BL18) on the serum concentrations of tumor specific growth factor (TSGF) and tumor necrosis factor α (TNF-α) in a rat model with precancerous lesion of primary hepatocellular carcinoma (HCC), so as to explore the mechanism of moxibustion underlying improvement of HCC. METHODS: Sixty male Wistar rats were randomly divided into control group (n=10), model group (n=20), prevention group 1 (n=15) and prevention group 2 (n=15). The normal rats were injected with physiological saline as blank control. At the same time, the rats of other three groups were injected with diethylnitrosamine to establish the HCC model. Direct moxibustion with grain-sized moxa was applied to bilateral Ganshu acupoint of the rats in the prevention group 1 (1 treatment course, 20 days) and prevention group 2 (2 treatment courses, 40 days), 5 doses for each acupoint, 0.5 mg/dose, once every other day. At each time point (before model establishment, the end of 1st course prevention, the end of 2nd course prevention and the end of model establishment), serum levels of TSGF and TNF-α were detected using enzyme-linked immunosorbent assay. RESULTS: Compared with the control group, there was a remarkably increase of serum TSGF and TNF-α contents in the model group at the end of the experiment (P<0.05). At the end of the 1st course of direct moxibustion, the contents of serum TSGF and TNF-α of rats in the prevention group 1 were significantly increased compared with that of the model group (P<0.05). At the end of the 2nd course of direct moxibustion, serum TSGF and TNF-α levels of rats in the model group were higher than the normal group with significantly difference (P<0.05), and the levels of TSGF and TNF-α in the prevention group 2 were significantly reduced in comparison with the model group (P<0.05). CONCLUSION: It was possible that direct moxibustion could inhibit precancerous lesion and postpone hepatocarcinogenesis, and the therapeutic effect of two courses were better than one course.


Assuntos
Pontos de Acupuntura , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Moxibustão , Proteínas de Neoplasias/sangue , Lesões Pré-Cancerosas/sangue , Fator de Necrose Tumoral alfa/sangue , Animais , Masculino , Ratos Wistar
10.
Luminescence ; 31(5): 1109-14, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26663583

RESUMO

At different temperatures (298, 310 and 318 K), the interaction between gliclazide and bovine serum albumin (BSA) was investigated using fluorescence quenching spectroscopy, resonance light scattering spectroscopy and UV/vis absorption spectroscopy. The first method studied changes in the fluorescence of BSA on addition of gliclazide, and the latter two methods studied the spectral change in gliclazide while BSA was being added. The results indicated that the quenching mechanism between BSA and gliclazide was static. The binding constant (Ka ), number of binding sites (n), thermodynamic parameters, binding forces and Hill's coefficient were calculated at three temperatures. Values for the binding constant obtained using resonance light scattering and UV/vis absorption spectroscopy were much greater than those obtained from fluorescence quenching spectroscopy, indicating that methods monitoring gliclazide were more accurate and reasonable. In addition, the results suggest that other residues are involved in the reaction and the mode 'point to surface' existed in the interaction between BSA and gliclazide. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Gliclazida/química , Espalhamento de Radiação , Soroalbumina Bovina/química , Animais , Bovinos , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
12.
Int J Clin Exp Pathol ; 7(8): 5324-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25197418

RESUMO

The study aims to find a new biomarker in hypertension. Our study is the first time to demonstrate that the CD62P small microparticle (diameter is <0.5 um) was a new microparticle population and a new biomarker in hypertension.


Assuntos
Biomarcadores/sangue , Micropartículas Derivadas de Células/metabolismo , Hipertensão/sangue , Selectina-P/sangue , Adulto , Idoso , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade
13.
PLoS One ; 9(8): e104528, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25116867

RESUMO

OBJECTIVES: Several recent lines of evidence indicate that endothelial microparticles are a new biomarker that can be used to monitor endothelial dysfunction in coronary artery disease (CAD). However, data concerning the detection of small microparticles (diameter <0.5 µm) are lacking. The aim of this study was to detect small-size endothelial microparticles (SEMPs) in CAD patients to monitor endothelial dysfunction. METHODS: In total, 19 CAD patients and 14 healthy subjects were recruited. The absolute numbers and percentages of CD31(+)/CD42b- SEMPs and CD62E(+) SEMPs were determined by flow cytometry. Clinical parameters were also recorded. RESULTS: The mean percentage of CD62E(+) SEMPs was higher in the CAD patient group than in the healthy subject group. The area under the receiver operating characteristic curve of the percentage of CD62E(+) SEMPs was 0.795, and the cut-off value was 1.35. There was no correlation between the percentage of CD62E(+) SEMPs and various clinical parameters. CONCLUSION: The percentage of CD62E(+) SEMPs is a potential biomarker for monitoring endothelial function in CAD.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Doença da Artéria Coronariana/metabolismo , Células Endoteliais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Casos e Controles , Micropartículas Derivadas de Células/química , Doença da Artéria Coronariana/sangue , Selectina E/metabolismo , Endotélio Vascular/metabolismo , Feminino , Citometria de Fluxo , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco
14.
Zhen Ci Yan Jiu ; 39(3): 211-5, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25069198

RESUMO

OBJECTIVE: To observe the effect of moxibustion at "Ganshu" (BL18) on levels of Livin (a novel member of the inhibitors of apoptosis family and plays crucial roles in apoptosis, cell proliferation, and cell cycle control) in the liver tissue in rats with precancerous lesion of primary hepatocellular carcinoma (HCC), so as to explore its mechanism underlying improvement of HCC. METHODS: Sixty male Wistar rats were randomly divided into control group (n = 10), model group (n = 20), moxibustion-20 d group (n = 15) and moxibustion-40 d group (n = 15). HCC model was established by intraperitoneal injection of diethylnitrosamine (DEN, 50 mg/kg), once every 3 days for 12 weeks. Moxibustion was applied to bilateral "Ganshu" (BL 18), once every other day for 10 times (moxibustion-20 d group) and 20 times (moxibustion-40 d group), respectively. Serum alpha-fetoprotein (AFP) content was detected with ELISA and Livin immunoactivity of the liver tissue detected using immunohistochemistry. RESULTS: After modeling, serum AFP content and liver Livin immunoactivity of the model group were significantly increased in comparison with the control group (P < 0.01). After moxibustion treatment, serum AFP content in the moxibustion-20 d group and liver Livin immunoactivity in both moxibustion-20 d and moxibustion-40 d groups were remarkably down-regulated in comparison with the model group (P < 0.05). No significant differences were found between the moxibustion-40 d group and the model group in serum AFP content (P > 0.05). CONCLUSION: Moxibustion can down-regulate liver Livin protein expression, which probably has a role in promoting hepatocellular apoptosis to inhibit precancerous lesion and to postpone hepatocarcinogenesis.


Assuntos
Pontos de Acupuntura , Carcinoma Hepatocelular/terapia , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Hepáticas/terapia , Fígado/metabolismo , Moxibustão , alfa-Fetoproteínas/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Wistar
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(12): 3262-6, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25881420

RESUMO

The purpose of the present paper is to determine calcium and magnesium in tobacco using NIR combined with least squares-support vector machine (LS-SVM). Five hundred ground and dried tobacco samples from Qujing city, Yunnan province, China, were surveyed by a MATRIX-I spectrometer (Bruker Optics, Bremen, Germany). At the beginning of data processing, outliers of samples were eliminated for stability of the model. The rest 487 samples were divided into several calibration sets and validation sets according to a hybrid modeling strategy. Monte-Carlo cross validation was used to choose the best spectral preprocess method from multiplicative scatter correction (MSC), standard normal variate transformation (SNV), S-G smoothing, 1st derivative, etc., and their combinations. To optimize parameters of LS-SVM model, the multilayer grid search and 10-fold cross validation were applied. The final LS-SVM models with the optimizing parameters were trained by the calibration set and accessed by 287 validation samples picked by Kennard-Stone method. For the quantitative model of calcium in tobacco, Savitzky-Golay FIR smoothing with frame size 21 showed the best performance. The regularization parameter λ of LS-SVM was e16.11, while the bandwidth of the RBF kernel σ2 was e8.42. The determination coefficient for prediction (Rc(2)) was 0.9755 and the determination coefficient for prediction (Rp(2)) was 0.9422, better than the performance of PLS model (Rc(2)=0.9593, Rp(2)=0.9344). For the quantitative analysis of magnesium, SNV made the regression model more precise than other preprocess. The optimized λ was e15.25 and σ2 was e6.32. Rc(2) and Rp(2) were 0.9961 and 0.9301, respectively, better than PLS model (Rc(2)=0.9716, Rp(2)=0.8924). After modeling, the whole progress of NIR scan and data analysis for one sample was within tens of seconds. The overall results show that NIR spectroscopy combined with LS-SVM can be efficiently utilized for rapid and accurate analysis of calcium and magnesium in tobacco.


Assuntos
Cálcio/análise , Magnésio/análise , Nicotiana/química , Calibragem , China , Análise dos Mínimos Quadrados , Modelos Teóricos , Espectroscopia de Luz Próxima ao Infravermelho , Máquina de Vetores de Suporte
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 33(3): 306-12, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21718615

RESUMO

OBJECTIVE: To explore the effect of N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide(W7) on the differentiation from human adipose-derived mesenchymal stem cells (hADSCs) to endothelial cells. METHODS: hADSCs were cultured with serum-free differential medium containing 40 ng/ml vascular endothelial growth factor (VEGF) and 10ng/ml basic fibroblast growth factor (bFGF). Cells were divided into control group (differential medium without W7), high-dose group (containing 30 µmol/L W7), medium-dose group (containing 20 µmol/L W7), and low-dose group ( containing 10 µmol/L W7). The hADSCs were cultured for 8 days, and then the changes in the phenotypes of von Willebrand factor (vWF) and vessel-selective cadherin (VE-Cadherin) were detected by flow cytometry (FCM). The intracellular Ca(2+) labeled with Fluo-3 was detected by laser confocal microscopy. After hADSCs planting on Matrigel, their angiogenic potentials were observed under the inverted phase contrast microscope, and the expression of extracellular regulated kinase (ERK) and phosphorylated extracellular regulated kinase (p-ERK) were evaluated by Western blot. RESULTS: After the hADSCs were cultured for 8 days, compared with the control group, the expressions of vWF and VE-Cadherin significantly increased along with the decrease of W7 level and the intracellular Ca(2+) also significantly increased (Pü0.01). Lumina-like vascular structure was formed in W7 treatment groups, but not in the blank control group. Compared with the blank control group, the expression of ERK showed no significant in W7 treatment groups (high-, medium-, and low-dose groups)(P>0.05); however, along with the decrease of W7 levels, the expression of p-ERK significantly increased(P<0.05). CONCLUSION: W7 in proper levels can effectively induce the differentiation from hADSCs to endothelium by increasing the intracellular Ca(2+) level and thus activating the ERK/MAPK pathway.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular/efeitos dos fármacos , Células Endoteliais/citologia , Células-Tronco Mesenquimais/citologia , Sulfonamidas/farmacologia , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo
18.
Zhongguo Zhong Yao Za Zhi ; 30(8): 600-2, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16011285

RESUMO

OBJECTIVE: To establish the determination method for complanatoside A in seeds of Astragalus complanatus. METHOD: An HPLC method has been developed to separate complanatoside A on ZORBAX EXTEND-C18 (4.6 mm x 250 mm, 5 microm) column with acetonitrile-water-phosphoric acid (20:80:0.2) as mobile phase and UV detection at 267 nm. RESULT: The good linearity of complanatoside A ranged 0.086-0.430 microg, r = 0.9999. An average recovery of 99.8% (n = 5) was obtained with a RSD of 1.0%. CONCLUSION: The established method is proved to be stability, fast, accurate and can be used for quantification of Complanatoside A in Semen Astragali Complanati.


Assuntos
Astrágalo/química , Flavonóis/análise , Glucosídeos/análise , Plantas Medicinais/química , Cromatografia Líquida de Alta Pressão/métodos , Controle de Qualidade , Sementes/química
19.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 27(1): 81-6, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15782499

RESUMO

OBJECTIVE: To explore dysfunction mechanism of rat alveolar type II (AT-II) injured by bleomycin (BLM). METHODS: SD rats were injected with a single intratracheal dose of bleomycin or control saline. On day 7, 14, and 28 following intratracheal bleomycin or saline instillation, animals were killed under overdose of 1.5% sodium pentobarbital (0.25 ml/100 g, i.p.) and bronchoalveolar lavage fluid (BALF) from the lung was tested for the activity of pulmonary surfactant (PS) by the Whihelmy Film Balance. Several concentrations of bleomycin stimulated the culture of rat AT-II cells, and surfactant protein (SP) A, B, and aquaporin-1 (AQP) mRNA were analyzed by fluorescent quantitative polymerase chain reaction (FQ-PCR). RESULTS: The activity of PS and hypoxemia significantly decreased on day 7 and improved on day 14 and completely recovered to normal status on day 28. SP-A, B, and AQP-1 mRNA expression in BLM-stimulated group were significantly lower than those in the control group (P<0.001). CONCLUSION: BLM-injured AT-II cells decrease the levels of SP-A, B, and AQP-1 mRNA and cause PS dysfunction, resulting in hypoxemia and pneumonedema.


Assuntos
Aquaporina 1/biossíntese , Bleomicina/toxicidade , Alvéolos Pulmonares/citologia , Proteína A Associada a Surfactante Pulmonar/biossíntese , Proteína B Associada a Surfactante Pulmonar/biossíntese , Animais , Aquaporina 1/genética , Bleomicina/administração & dosagem , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Hipóxia/induzido quimicamente , Hipóxia/metabolismo , Hipóxia/patologia , Masculino , Alvéolos Pulmonares/efeitos dos fármacos , Proteína A Associada a Surfactante Pulmonar/genética , Proteína B Associada a Surfactante Pulmonar/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
20.
J Environ Sci (China) ; 16(3): 436-42, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15272719

RESUMO

The purpose of this article is to identify the effect of land-use pattern on rainfall-runoff and runoff-sediment relations in Zichang Watershed of the Loess Plateau. From 1986 to 1997, many farmlands changed into grassland or woodland, especially the farmland in steep slope positions or far away from the river. The change of land-use pattern altered the rainfall-runoff and runoff-sediment relationships, and led to higher slope of trend curves (STCs) of annual rainfall-runoff mass curve and runoff-sediment mass curve in 1990s than that in 1980s. It is implied that more soil and water loss yielded in 1990s. In order to reduce soil loss, more attentions should be paid to land-use pattern and some grass or other herbaceous filter strips should be built along rivers.


Assuntos
Conservação dos Recursos Naturais , Sedimentos Geológicos/análise , Chuva , Solo , Movimentos da Água , Agricultura , China , Ecossistema , Monitoramento Ambiental , Filtração
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