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Objective To investigate the impact of microvascular obstruction (MVO) on the global and regional myocardial function by cardiac magnetic resonance feature-tracking (CMR-FT) in ST-segment-elevation myocardial infarction (STEMI) patients after percutaneous coronary intervention.Methods Consecutive acute STEMI patients who underwent cardiac magnetic resonance imaging 1 - 7 days after successful reperfusion by percutaneous coronary intervention treatment were included in this retrospective study. Based on the presence or absence of MVO on late gadolinium enhancement images, patients were divided into groups with MVO and without MVO. The infarct zone, adjacent zone, and remote zone were determined based on a myocardial 16-segment model. The radial strain (RS), circumferential strain (CS), and longitudinal strain (LS) of the global left ventricle (LV) and the infarct, adjacent, and remote zones were measured by CMR-FT from cine images and compared between patients with and without MVO using independent-samples t-test. Logistic regression analysis was used to assess the association of MVO with the impaired LV function.Results A total of 157 STEMI patients (mean age 56.66 ± 11.38 years) were enrolled. MVO was detected in 37.58% (59/157) of STEMI patients, and the mean size of MVO was 3.00 ±3.76 mL. Compared with patients without MVO (n =98 ), the MVO group had significantly reduced LV global RS (t= -4.30, P < 0.001), global CS (t= 4.99, P < 0.001), and global LS ( t= 3.51, P = 0.001). The RS and CS of the infarct zone in patients with MVO were significantly reduced (t= -3.38, P = 0.001; t= 2.64, P = 0.01; respectively) and the infarct size was significantly larger (t= 8.37, P < 0.001) than that of patients without MVO. The presence of LV MVO [OR= 4.10, 95%CI: 2.05 - 8.19, P<0.001) and its size [OR=1.38, 95%CI: 1.10-1.72, P=0.01], along with the heart rate and LV infarct size were significantly associated with impaired LV global CS in univariable Logistic regression analysis, while only heart rate (OR=1.08, 95%CI: 1.03 - 1.13, P=0.001) and LV infarct size (OR=1.10, 95%CI: 1.03 - 1.16, P=0.003) were independent influencing factors for the impaired LV global CS in multivariable Logistic regression analysis.Conclusion The infarct size was larger in STEMI patients with MVO, and MVO deteriorates the global and regional LV myocardial function.
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Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Pessoa de Meia-Idade , Idoso , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Meios de Contraste , Estudos Retrospectivos , Gadolínio , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância MagnéticaRESUMO
BACKGROUND: Fertility desire for a second child has been a lively topic since the implementation of the two-child policy in China. Chinese researchers have explored various factors influencing the fertility desire for a second child. However, there have not been studies on the individual differences in the relative fertility costs and fertility benefits and their effects on fertility desire for a second child. METHODS: A total of 396 participants rated four kinds of relative fertility costs, four kinds of fertility benefits and their fertility desire for a second child. Latent profile analysis (LPA) was used to explore the individual differences in the relative fertility costs and fertility benefits and their effects on fertility desire for a second child. RESULTS: Stepwise regression analysis showed that parenting joy, health risks, mutual care among siblings, the flourishing of family, and time pressure and opportunity cost significantly predicted the fertility desire for the second child. According to the latent profile analysis, the participants were classified into four classes. Participants in the lowest-cost/lowest-benefit and high-cost/medium-benefit classes had low fertility desire for a second child, while those in the low-cost/high-benefit and highest-cost/highest-benefit classes had high fertility desire. CONCLUSION: Fertility benefits have a stronger effect on the fertility desire for a second child than relative fertility costs. Fertility benefits should be paid more attention to than relative fertility costs.
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Análise Custo-Benefício , Política de Planejamento Familiar/legislação & jurisprudência , Fertilidade , Individualidade , Gravidez/psicologia , Adulto , China , Características da Família , Feminino , Humanos , Dinâmica PopulacionalRESUMO
Objective To observe the effect of Fuzheng Kang'ai Recipe (FKR) combined ge- fitinib on the proliferation and apoptosis of lung cancer A549 cells , and to study its potential synergistic mechanish with gefitinib. Methods The effects of FKR (0. 211, 0. 316, 0. 474, 0. 711, 1. 067, 1. 600, 2. 400, 3. 600 mg/mL) combined gefitinib (3. 95, 5. 92, 8. 18, 13. 33, 20. 00, 30. 00, 45. 00, 67. 50 µmol/ L) on the proliferation of A549 cells were detected by MTT assay. The apoptosis of A549 cells in the control group (complete culture medium) , FKR (1. 6 mg/mL) , gefitinib (45 µmol/L) , and FKR plus gefitinib (1. 6 mg/mL +45 µmol/L) were detected by flow cytometry (FCM). Their expressions of epidermal growth factor receptor (EGFR) , phosphorylating epidermal growth factor receptor ( p-EGFR) , enhancer of zeste homolog 2 (EZH2), peroxisome proliferator-activated receptor-γ ( PPAR-γ) , and P53 protein in A549 cells were detected by Western blot. Results Both FKR and gefitinib could inhibit the proliferation of A549 cells. The apoptotic rate was 12. 6% ±4. 5% in the FKR combined gefitinib group, obviously higher than that of the FKR group (4. 6% ± 0. 7%) and the gefitinib group (7. 8% ± 2. 7%) , showing statistical difference (P <0. 05). Compared with the control group, the expressions of p-EGFR and EZH2 were sig- nificantly down-regulated (P <0. 05) , the expressions of PPAR-γ and P53 protein were up-regulated in the FKR combined gefitinib group (P <0. 05); the expression of EZH2 was down-regulated in the gefitinib group and the FKR group (P <0. 05) ; the expression of PPAR-y was up-regulated in the FKR group (P < 0. 05). Compared with the gefitinib group, the expression of p-EGFR was down-regulated, and the expression of PPAR-γ was up-regulated in the FKR combined gefitinib group (both P <0. 05). Compared with the FKR group, the expression of p-EGFR was down-regulated in the FKR combined gefitinib group (P < 0. 05). Conclusions Combination of FKR and gefitinib could significantly inhibit the proliferation and growth of A549 cells,and induce cell apoptosis. Its potential synergistic mechanism of anti-tumor activities might be associated with down-regulating mRNA expressions of p-EGFR and EZH2, and up-regulating protein expressions of PPAR-y and P53.
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Antineoplásicos , Apoptose , Carcinoma Pulmonar de Células não Pequenas , Medicamentos de Ervas Chinesas , Gefitinibe , Neoplasias Pulmonares , Células A549 , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Medicamentos de Ervas Chinesas/uso terapêutico , Receptores ErbB , Gefitinibe/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , QuinazolinasRESUMO
OBJECTIVE: To evaluate the associations of lipid indicators and mortality in Beijing Elderly Comprehensive Health Cohort Study. METHODS: A prospective cohort was conducted based on Beijing Elderly Comprehensive Health Cohort Study with 4499 community older adults. After the baseline survey, the last follow-up was March 31, 2021 with an average 8.13 years of follow-up. Cox proportional hazard model was used to estimate the hazard ratios (HR) with 95% CI for cardiovascular disease (CVD) death and all-cause death in associations with baseline lipid indicators. RESULTS: A total of 4499 participants were recruited, and the mean levels of uric acid, body mass index, systolic blood pressure, diastolic blood pressure, fasting plasma glucose, total cholesterol (TC), triglyceride, and low-density lipoprotein cholesterol (LDL-C) showed an upward trend with the increasing remnant cholesterol (RC) quarters (Ptrend < 0.05), while the downward trend was found in high-density lipoprotein cholesterol (HDL-C). During the total 36,596 person-years follow-up, the CVD mortality and all-cause mortality during an average 8.13 years of follow-up was 3.87% (95% CI: 3.30%-4.43%) and 14.83% (95% CI: 13.79%-15.86%) with 174 CVD death participants and 667 all-cause death participants. After adjusting for confounders, the higher level of TC (HR = 0.854, 95% CI: 0.730-0.997), LDL-C (HR = 0.817, 95% CI: 0.680-0.982) and HDL-C (HR = 0.443, 95% CI: 0.271-0.724) were associated with lower risk of CVD death, and the higher level of HDL-C (HR = 0.637, 95% CI: 0.501-0.810) were associated with lower risk of all-cause death. The higher level of RC (HR = 1.276, 95% CI: 1.010-1.613) increase the risk of CVD death. Compared with the normal lipid group, TC ≥ 6.20 mmol/L group and LDL-C ≥ 4.10 mmol/L group were no longer associated with lower risk of CVD death, while RC ≥ 0.80 mmol/L group was still associated with higher risk of CVD death. In normal lipid group, the higher levels of TC, LDL-C and HDL-C were related with lower CVD death. CONCLUSIONS: In community older adults, higher levels of TC and HDL-C were associated with lower CVD mortality in normal lipid reference range. Higher RC was associated with higher CVD mortality, which may be a better lipid indicator for estimating the CVD death risk in older adults.
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The rhizome of Alpinia officinarum is a widely used Chinese herbal medicine. The essential oil in A. officinarum rhizome is mainly composed of 1, 8-cineole and other monoterpenes, as the major bioactive ingredients. In plants, monoterpenes are synthesized through the methylerythritol phosphate (MEP) pathway in the plastids, and 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) is an enzyme catalyzing a committed step of the MEP pathway. In the present study, the full-length cDNA encoding DXR was cloned from the rhizome of A. officinarum, using homology-based RT-PCR and rapid amplification of cDNA ends (RACE) techniques. The new cDNA was designated as AoDXR and submitted to GenBank to be assigned with an accession number HQ874658. The full-length cDNA of AoDXR was 1 670 bp containing a 1 419 bp open reading frame encoding a polypeptide of 472 amino acids with a calculated molecular mass of 51.48 kDa and an isoelectric point of 6.15. Bioinformatic analyses revealed that AoDXR showed extensive homology with DXRs from other plant species and contained a conserved plastids transit peptide, a Pro-rich region and two highly conserved NADPH-binding motifs in its N-terminal region characterized by all plant DXRs. The phylogenetic analysis revealed that AoDXR belonged to angiosperm DXRs. The structural modeling of AoDXR showed that AoDXR had the typical V-shaped structure of DXR proteins. The tissue expression pattern analysis indicated that AoDXR expressed strongly in leaves, weak in rhizomes of A. officinarum. Exogenous methyl jasmonate (MeJA) could enhance the expression of AoDXR and the production of 1, 8-cineole in A. officinarum rhizomes. The cloning and characterization of AoDXR will be helpful to reveal the molecular regulation mechanism of monoterpene biosynthesis in A. officinarum and provides a candidate gene for metabolic engineering in improving the medicinal quality of A. officinarum rhizome.
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Aldose-Cetose Isomerases/genética , Alpinia/enzimologia , DNA Complementar/genética , Alpinia/química , Alpinia/genética , Sequência de Aminoácidos , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Monoterpenos/metabolismo , FilogeniaRESUMO
Ornithine decarboxylase (ODC), the first rate-limiting enzyme of polyamine biosynthesis, was found to be associated with cell growth, proliferation and transformation. ODC gene expression in gastric cancer was increased and its level was positively correlated with the degree of malignity of gastric mucosa and development of gastric lesions. In order to evaluate the therapeutic effects of antisense RNA of ODC on gastric cancer, an antisense RNA of ODC expressing plasmid pcDNA-ODCr which delivered a 120 bp fragment complementary to the initiation codon of ODC gene was constructed and transfected to gastric cancer cells SGC7901 and MGC803. Expression of ODC in gastric cancer cells was determined by western blot. Cell proliferation was assessed by MTS assay. Cell cycle was analyzed by flow cytometry and Matrigel assay was performed to assess the ability of gastric cancer cell invasiveness. The results showed that the ODC gene expression in gastric cancer cells transfected with the pcDNA-ODCr was downregulated efficiently. Tumor cell proliferation was suppressed significantly, and cell cycle was arrested at G1 phase. Gastric cancer cells had reduced invasiveness after gene transfer. Our study suggested that antisense RNA of ODC expressing plasmid pcDNA-ODCr had antitumor activity by inhibiting the expression of ODC, and downregulation of ODC expression using a gene therapy approach might be a novel therapeutic strategy for gastric cancer.
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Regulação Neoplásica da Expressão Gênica , Ornitina Descarboxilase/biossíntese , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/terapia , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Colágeno/química , Combinação de Medicamentos , Citometria de Fluxo/métodos , Perfilação da Expressão Gênica , Técnicas de Transferência de Genes , Terapia Genética/métodos , Humanos , Laminina/química , Oligonucleotídeos Antissenso/genética , Plasmídeos/metabolismo , Proteoglicanas/química , RNA/metabolismoRESUMO
RNA interference (RNAi) techniques have emerged as powerful tools that facilitate development of novel management strategies for insect pests, such as Henosepilachna vigintioctopunctata (Coleoptera: Coccinellidae), which is a major pest of solanaceous plants in Asia. In this study, the potential of oral delivery of in vitro-synthesized and bacterially expressed double-stranded H. vigintioctopunctata lesswright (lwr) gene (dsHvlwr) to manage of H. vigintioctopunctata was investigated. Our results showed that the gene Hvlwr had a 480-bp open reading frame and encoded a 160-amino acid protein. Hvlwr expression levels were greater in the fat body than other tissue types. Hvlwr silencing led to greater H. vigintioctopunctata mortality rates and appeared to be time- and partially dose-dependent, likely as a result of the number of hemocytes increasing with dsRNA concentration, but decreasing with time. Bacterially expressed dsHvlwr that was applied to leaf discs caused 88%, 66%, and 36% mortality in 1st instars, 3rd instars, and adults after 10, 10, and 14 d, respectively; when applied to living plants, there was greater mortality in 1st and 3rd instars, but there was no effect on adults. Furthermore, dsHvlwr led to improved plant protection against H. vigintioctopunctata. Our study shows an effective dietary RNAi response in H. vigintioctopunctata and that Hvlwr is a promising RNAi target gene for control of this pest species.
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Besouros/fisiologia , Controle de Insetos/métodos , Proteínas de Insetos/genética , Interferência de RNA , Animais , Besouros/genética , Besouros/crescimento & desenvolvimento , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/fisiologia , Pupa/crescimento & desenvolvimento , Pupa/fisiologiaRESUMO
Tumstatin is the 28 kDa NC1 domain of the alpha3 chain of type IV collagen that inhibits pathological angiogenesis and suppresses endothelial cell proliferation and tumor growth. In the present paper, we expressed and purified recombinant human tumstatin protein and then prepared the anti-tumstatin polyclonal antibody. To investigate the expression of tumstatin in renal carcinoma, tumstatin protein was detected by western blotting using the prepared anti-tumstatin antibody and tumstatin mRNA levels were assayed by RT-PCR. The results showed that the expression of tumstatin gene was down-regulated in renal carcinoma tissues and cells. Our study suggests that as a novel endogenous angiogenesis inhibitor, tumstatin gene expression may be a marker for diagnosis, therapy and prognosis of renal carcinoma.
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Autoantígenos/genética , Colágeno Tipo IV/genética , Regulação para Baixo/genética , Neoplasias Renais/genética , Anticorpos Antineoplásicos/biossíntese , Autoantígenos/imunologia , Autoantígenos/isolamento & purificação , Autoantígenos/metabolismo , Clonagem Molecular , Colágeno Tipo IV/imunologia , Colágeno Tipo IV/isolamento & purificação , Colágeno Tipo IV/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Rim/metabolismo , Rim/patologia , Neoplasias Renais/imunologia , Neoplasias Renais/patologiaRESUMO
1. UbcH10 is the cancer-related E2 ubiquitin-conjugating enzyme, and its overexpression has been demonstrated in a variety of malignancies. The aim of the present study is to silence UbcH10 gene by RNA interference (RNAi) and to observe its inhibitory effect on the colorectal cancer cell growth in vitro and in vivo. 2. We constructed the expression vector pGPU6/GFP/Neo/UbcH10-RNAi (pUbcH10-RNAi), which contained a UbcH10 short hairpin RNA expression cassette. Then the UbcH10 gene silencing cell lines LoVo/UbcH10-RNAi and HT-29/UbcH10-RNAi were established. Reverse transcription-polymerase chain reaction and western blot analysis were used to evaluate the expression of the UbcH10 gene. Cell Counting Kit-8 was used to assess properties of tumour cell growth in vitro. Flow cytometry was used to detect the effect of pUbcH10-RNAi on the cell cycle of colorectal cancer cells. Furthermore, the anti-tumour effects of pUbcH10-RNAi were evaluated in vivo in a nude mouse xenografts model. 3. Results demonstrated that UbcH10 gene expression was significantly decreased in pUbcH10-RNAi treated cells. Colorectal cancer cells growth was markedly suppressed in the pUbcH10-RNAi group compared with control conditions and colorectal cancer cells were arrested in the G2-M phase. In vivo, the downregulation of UbcH10 gene expression by pUbcH10-RNAi also inhibited tumour growth in a nude mice xenograft model. 4. Our study suggests that RNA interference-mediated silencing of UbcH10 gene has anti-tumour activity on colorectal cancer and might have therapeutic potential for the treatment of colorectal cancer.
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Neoplasias Colorretais/terapia , Interferência de RNA , Enzimas de Conjugação de Ubiquitina/genética , Animais , Western Blotting , Divisão Celular/genética , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Regulação para Baixo , Fase G2/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Previous experimental studies have regarded distraction, an emotional regulation strategy, as an attentional disengagement strategy and considered it to be maladaptive in the long term. This study intends to further examine the relationship between distraction and negative emotions by using a questionnaire and a multiple mediation model. A total of 723 college students completed the distraction, cognitive reappraisal and problem-solving subscales of the Measurement of Affect Regulation Styles, the Needs Satisfaction Questionnaire, the Meaningful Life Measure, and the Emotional Experience Questionnaire of Well-being. Structural equation modeling (SEM) was performed, and mediation effects were tested. The results showed that (1) distraction was used significantly more frequently than problem-solving and cognitive reappraisal, with a large effect size (partial η2 = 0.321 > 0.138), and (2) distraction had an effect on negative emotions through two multiple mediation paths, i.e., positive emotion-cognitive reappraisal-meaning in life, and positive emotion-problem-solving-needs satisfaction. Distraction reduces negative emotions by enhancing positive emotions and facilitating cognitive reappraisal, problem-solving, meaning in life and needs satisfaction. It is not a kind of avoidance but a temporary rest to strive for a better life.
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Regulação Emocional , Resolução de Problemas , Estudantes , Adulto , Atenção , China , Cognição , Emoções , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Spermidine/spermine N(1)-acetyltransferase (SSAT) is the rate-limiting step in polyamine catabolism. In a previous study, we constructed a recombinant adenovirus, Ad-SSAT, which can express human SSAT. In the present study, we investigated the effect of upregulated and downregulated SSAT on gastric cancer cells. We found that upregulated SSAT could inhibit the growth of MGC803 and SGC7901 cells, whereas adverse results were found with downregulated SSAT. We further analyzed cell cycle profiles and the expression levels of the major cell cycle regulatory proteins of S phase. The results showed that the growth inhibition was caused by S phase arrest. Ad-SSAT suppressed the expression of cyclin A and nuclear factor E2F1 in MGC803 and SGC7901 cells. We observed the E2F promoter activity caused by Ad-SSAT using a reporter gene assay. We also investigated the antitumorigenicity of upregulated SSAT by Ad-SSAT using a SGC7901 xenograft model in nude mice. Our results suggest that the upregulation of SSAT by Ad-SSAT infection inhibited the growth of gastric cancer in vitro and in vivo. Ad-SSAT arrested gastric cancer cells in S phase, which was mediated through downregulation of the cyclin A-E2F signaling pathway.
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Acetiltransferases/fisiologia , Adenoviridae/genética , Neoplasias Gástricas/prevenção & controle , Acetiltransferases/genética , Animais , Poliaminas Biogênicas/análise , Linhagem Celular Tumoral , Ciclina A/antagonistas & inibidores , Fator de Transcrição E2F1/antagonistas & inibidores , Vetores Genéticos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fase S , Neoplasias Gástricas/química , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia , Regulação para CimaRESUMO
The adult employees suffer from various pressure and their mental health has been paid more and more attention to. This study has two purposes, namely, (1) to investigate the gender differences in the stressors and utilization frequency of problem-focused coping among adult employees and (2) to explore the gender differences in the interaction effect of cumulative risk and problem-focused coping on depression among adult employees. The cumulative risk of employees was assessed in the following six ways: health pressure, family economic pressure, love and marriage problems, conflicts among family members, work stress and friend support. Problem-focused coping was measured by the three dimensions of active coping, planning, and using instrumental support from the Brief COPE scale, and depression was assessed by the Self-rating Depression Scale. The participants consisted of 406 Chinese employees. The results showed that (1) the cumulative risk of male employees was marginally significantly higher than that of female employees; (2) there was no significant difference in the utilization frequency of problem-focused coping between male and female employees; and (3) problem-focused coping moderated the relationship between cumulative risk and depression for male employees but not for female employees. This study indicates that problem-focused coping has a stronger effect on depression for male employees than for female employees.
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Adaptação Psicológica , Depressão/psicologia , Adolescente , Adulto , Depressão/patologia , Feminino , Humanos , Masculino , Razão de Chances , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Estresse Psicológico , Inquéritos e Questionários , Adulto JovemRESUMO
Carbon dots capped with polyethyleneimine (CD-PEI) were synthesized and applied in selective separation and preconcentration of trace Cr(VI). Dispersed particle extraction (DPE) slurry sampling with flame atomic absorption spectrometry (FAAS) was used to selectively and sensitively determine Cr(VI) in water samples. The as-synthesized CD-PEI was confirmed by Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy, elemental analysis, fluorescence and zeta potential measurement. The adsorption of Cr(VI) on CD-PEI was evaluated. Its isothermal adsorption was studied and fitted in the Langmuir model. Nearly 85% of Cr(VI) was adsorbed within 10 min showed that the CD-PEI exhibited fairly fast kinetics for the sorption of Cr(VI). Experimental conditions, including the content and size of CD-PEI, sample pH, adsorption time, sample volume, slurry volume and interfering ions, were further optimized to obtain efficient preconcentration and high-precision determination of Cr(VI). CD-PEI with small size turned to be a good candidate for the preparation of slurry. CD-PEI served not only as a promising adsorbent for separation and preconcentration of Cr, but also a signal-enhancing agent in FAAS. The method achieved an enhancement factor of 30 and a detection limit (S/N=3) of 0.21 µg L(-1) Cr(VI) with a consumption of 14.0 mL sample and an adsorption time of 5 min, which provided two times of signal enhancement. The RSD for 11 replicate measurements of 5.0 µg L(-1) Cr(VI) was 2.8%. The possible signal enhancement mechanism was proposed. The developed method has been applied to determine trace Cr(VI) in a variety of water samples.
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The PCR technique has been set up for nearly twenty years and is becoming more and more ripe. But because of the multiple influencing factors and complicated reaction procedures,no mathematical method that can describe the PCR reaction has been given. On the basis of its elementary principle,we suggested a kinetic equation to describe the reaction procedure,Wamp=[Ntarg x (1+P)n1+0.5 x Cenz x U x P x Ceactive x (n-nl)-Ntarg x (1+n x P)] x Cu x M. This equation can describe correctly the accumulation rule of PCR product and thus build up the kinetic-mathematical model of PCR reaction. The predicted CT value of PE 7700 by the kinetic-mathematical model was in accordance with the real value detected by the machine. This kinetic-mathematical model accompanied by proper detecting equipment and computer could make an automatic PCR instrument, which would produce much better result. A laboratory can predict the amount of PCR product by this model and provide accurate information for further handling of PCR product according to its own condition. In this model,the molecular basis that PCR reaction is doomed to change from exponential amplification to linear amplification had been clarified.
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Today standard PCR can't satisfy the need of biotechnique development and clinical research any more. After numerous dynamic research, PE company found there is a linear relation between initial template number and cycling time when the accumulating fluorescent product is detectable.Therefore,they developed a quantitative PCR technique to be used in PE7700 and PE5700. But the error of this technique is too great to satisfy the need of biotechnique development and clinical research. A better quantitative PCR technique is needed. The mathematical model submitted here is combined with the achievement of relative science,and based on the PCR principle and careful analysis of molecular relationship of main members in PCR reaction system. This model describes the function relation between product quantity or fluorescence intensity and initial template number and other reaction conditions, and can reflect the accumulating rule of PCR product molecule accurately. Accurate quantitative PCR analysis can be made use this function relation. Accumulated PCR product quantity can be obtained from initial template number. Using this model to do quantitative PCR analysis,result error is only related to the accuracy of fluorescence intensity or the instrument used. For an example, when the fluorescence intensity is accurate to 6 digits and the template size is between 100 to 1,000,000, the quantitative result accuracy will be more than 99%. The difference of result error is distinct using same condition,same instrument but different analysis method. Moreover,if the PCR quantitative analysis system is used to process data, it will get result 80 times of accuracy than using CT method.
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AIM: To investigate the antihepatocellular carcinoma effects of chi-shen extract (CSE) from the water-soluble compounds of Salvia miltiorrhiza and Paeoniae radix. METHODS: The effect of CSE on the growth of HepG2 cells (hepatocellular carcinoma cell line) was studied by 3-(4,5)-2,5-diphenyltetrazolium bromide assay. Apoptosis were detected through acridine orange (AO) and ethylene dibromide (EB) staining and DNA fragmentation assay. The effect of CSE on the cell cycle of HepG2 cells was studied by the propidium iodide staining method. The activation of caspases-3, -8 and -9 was examined by immunoassay kits. The transcription of the Bcl-2 family and p53 was detected by RT-PCR. RESULTS: Our data revealed that CSE strongly induced HepG2 cell death in a dose- and time-dependent manner. CSE-induced cell death was considered to be apoptotic by observing the typical apoptotic morphological change by AO/EB staining and DNA fragmentation assay. The induction of HepG2 cell death was caused by an induction of apoptosis for the sub-G1 proportion increase, the downregulation of Bcl-2, the upregulation of Bax and p53, and the activation of the caspases-3 and -9 pathways. CONCLUSION: These results clearly demonstrated that CSE was able to inhibit the proliferation of HepG2 cells and cause apoptosis. Moreover, the anticancer effects of CSE were related to the Bcl-2 family pathway and the activation of caspases-3 and -9 in HepG2 cells.