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1.
Article in Chinese | MEDLINE | ID: mdl-36882274

ABSTRACT

Objective: To investigate the effect of oxidative stress caused by heat exposure on the blood pressure increase of treadmill rats and the intervention of antioxidants. Methods: In June 2021, Twenty-four healthy SD male rats were randomly divided into four groups: normal temperature feeding, normal temperature treadmill, high temperature treadmill and high temperature treadmill supplementation with vitamin C groups, 6 rats in each group. The rats run on the platform in normal temperature or heat exposure environment for 30 min in the morning and in the afternoon daily, 6 days per week. The daily vitamin C supplement dose of high temperature treadmill supplementation with vitamin C group was 10 mg/kg. BP recordings were done at the end of the week. The rat vascular lipofuscin (LF) was detected by ELISA, the rat serum nitric oxide (NO) was detected by nitrate reductase method, the serum malondialdehyde (MDA) was detected by thibabituric acid method, the serum glutathione peroxidase (GPx) and superoxide dismutase (SOD) were detected by chemiluminescence method, and the serum catalase (CAT) was detected by ammonium molybdate method. The total antioxidant capacity (T-AOC) of serum was measured by iron reduction/antioxidant capacity method, and the content of nuclear erythroid 2-related factor 2 (Nrf2) in vascular tissue was measured by Western blot. The intra-group mean was compared by repeated measurement analysis of variance, and the inter-group mean was compared by single-factor analysis of variance and post-event LSD-t test. Results: Compared with the previous time point, the systolic BP and diastolic BP of the high temperature treadmill group were significantly increased at 7, 14 and 21 d, and decreased at 28 d which were higher than the initial level (P<0.05), and the systolic BP and diastolic BP values at each experimental time point were significantly higher than those of normal temperature treadmill group (P<0.001). The changes of thickening of the artery wall, no smoothing of the endodermis and irregular arrangement of muscle cells in high temperature treadmill group were observed. Compared with the normal temperature treadmill group, the content of MDA in serum, and LF in vascular tissue were significantly increased, the activities of SOD, CAT, T-AOC, the content of NO in serum, and the expression of Nrf2 in vascular tissue were significantly decreased in high temperature treadmill group (P<0.05). Compared with the high temperature treadmill group, the systolic BP and diastolic BP values at 7, 14, 21 and 28 d, the content of serum MDA and LF in vascular tissue were significantly decreased, the activities of CAT and T-AOC, and the expression of Nrf2 in vascular tissue significantly increased (P<0.05), the histopathological changes of the artery wall improved in high temperature treadmill supplementation with vitamin C group. Conclusion: Heat exposure has effect on oxidative stress, which may be related to the increase of BP. Vitamin C as an anti-oxidative enhancer can prevent those negative effects, which could alleviate the pathological changes of vessel intima in heat-exposed rats. And the Nrf2 may be a regulated factor to vascular protection.


Subject(s)
Antioxidants , Ascorbic Acid , Animals , Male , Rats , Antioxidants/pharmacology , Blood Pressure , Hot Temperature , NF-E2-Related Factor 2 , Oxidative Stress
2.
Clin Radiol ; 76(6): 471.e17-471.e25, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33663913

ABSTRACT

AIM: To investigate the value of motion-corrected (MOCO) phase-sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) compared with single-shot balanced steady-state gradient echo ("TrueFISP", Siemens) PSIR in free breathing paediatric patients. MATERIALS AND METHODS: In this retrospective study, 238 paediatric patients underwent clinical contrast-enhanced cardiovascular magnetic resonance imaging (CMRI). Both the single-shot TrueFISP PSIR and MOCO PSIR sequences were performed on each child. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Two radiologists rated the quality of the images on a scale of 1-5 (1 = poor, 5 = very good). Bland-Altman, linear regression, and intraclass correlation coefficient were used to compared the extent of LGE of the single-shot TrueFISP PSIR and MOCO PSIR. Imaging artefacts were described and compared. RESULTS: Children ranged in age from 60 days to 17 years with an average age of 8.1 ± 3.8 years. MOCO PSIR had higher SNR and CNR than the single-shot TrueFISP PSIR (p<0.001). Mean quality ratings for short-axis imaging were 4 (interquartile range, 3-4) for single-shot TrueFISP PSIR and 4 (interquartile range, 4-5) for MOCO PSIR (p<0.001). The scan time was faster for single-shot TrueFISP PSIR than for MOCO PSIR. The myocardial LGE results were similar with high agreement between the single-shot TrueFISP PSIR and MOCO PSIR (ICC = 0.955-0.986). CONCLUSION: The MOCO PSIR sequence is feasible in children. MOCO PSIR is robust at high heart rates and can be performed without breath-holding with higher image-quality ratings than the single-shot TrueFISP PSIR.


Subject(s)
Contrast Media , Gadolinium , Heart Diseases/diagnostic imaging , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Adolescent , Child , Child, Preschool , Female , Heart/diagnostic imaging , Humans , Infant , Male , Respiration , Retrospective Studies
3.
BJOG ; 128(10): 1635-1644, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33586324

ABSTRACT

OBJECTIVE: To determine the optimal total serum bile acid (TSBA) threshold and sampling time for accurate intrahepatic cholestasis of pregnancy (ICP) diagnosis. DESIGN: Case-control, retrospective cohort studies. SETTING: Antenatal clinics, clinical research facilities. POPULATION: Women with ICP or uncomplicated pregnancies. METHODS: Serial TSBA measurements were performed pre-/postprandially in 42 women with ICP or uncomplicated pregnancy. Third-trimester non-fasting TSBA reference ranges were calculated from 561 women of black, south Asian and white ethnicity. Rates of adverse perinatal outcomes for women with ICP but peak non-fasting TSBA below the upper reference range limit were compared with those in healthy populations. MAIN OUTCOME MEASURES: Sensitivity and specificity of common TSBA thresholds for ICP diagnosis, using fasting and postprandial TSBA. Calculation of normal reference ranges of non-fasting TSBA. RESULTS: Concentrations of TSBA increased markedly postprandially in all groups, with overlap between healthy pregnancy and mild ICP (TSBA <40 µmol/l). The specificity of ICP diagnosis was higher when fasting, but corresponded to <30% sensitivity for diagnosis of mild disease. Using TSBA ≥40 µmol/l to define severe ICP, fasting measurements identified 9% (1/11), whereas non-fasting measurements detected over 91% with severe ICP. The highest upper limit of the non-fasting TSBA reference range was 18.3 µmol/l (95% confidence interval: 15.0-35.6 µmol/l). A re-evaluation of published ICP meta-analysis data demonstrated no increase in spontaneous preterm birth or stillbirth in women with TSBA <19 µmol/l. CONCLUSIONS: Postprandial TSBA levels are required to identify high-risk ICP pregnancies (TSBA ≥40 µmol/l). The postprandial rise in TSBA in normal pregnancy indicates that a non-fasting threshold of ≥19 µmol/l would improve diagnostic accuracy. TWEETABLE ABSTRACT: Non-fasting bile acids improve the diagnostic accuracy of intrahepatic cholestasis of pregnancy diagnosis.


Subject(s)
Bile Acids and Salts/blood , Cholestasis, Intrahepatic/diagnosis , Pregnancy Complications/diagnosis , Prenatal Diagnosis , Adult , Biomarkers/blood , Case-Control Studies , Cholestasis, Intrahepatic/blood , Cohort Studies , Female , Humans , Pregnancy , Pregnancy Complications/blood , Retrospective Studies , Sensitivity and Specificity
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(11): 1836-1842, 2020 Nov 10.
Article in Chinese | MEDLINE | ID: mdl-33297648

ABSTRACT

Objective: To investigate the effect of occupational factor exposures on carotid atherosclerosis (CAS) in steel workers. Methods: A frequency matched case-control study was conducted by age and factory proportion. A total of 1 033 workers with carotid atherosclerosis diagnosed by ultrasonography examination from February to June 2017 were selected as case group, and 1 033 workers without carotid atherosclerosis indicated by physical examination at the same time were selected as control group. The basic information of the workers, such as diet pattern, lifestyle, serum biochemical index and occupation history, were collected. The effects of occupational hazards on carotid atherosclerosis were analyzed by univariate and multivariate logistic regression analyses. The combined effects of various occupational hazards on carotid atherosclerosis were evaluated by environmental risk score (ERS). Results: High temperature, noise, occupational stress and night shift days increased the risk of CAS. With the increase of cumulative high temperature and noise exposure, occupational stress and night shift days, the risk of CAS increased (trend text: χ(2)=37.53, P<0.01; χ(2)=16.98, P<0.01; χ(2)=13.93, P<0.01; χ(2)=5.59, P<0.05). After adjustment of covariates, compared with P(20) group, the risk of carotid artery in P(40), P(60), P(80) and P(100) groups were as follows: high temperature 1.61 (1.19-2.18), 1.69 (1.25-2.30), 1.84 (1.36-2.49), 2.43 (1.77-3.34); noise 1.70 (1.15-2.52), 1.68 (1.20-2.35), 1.80 (1.34-2.42), 2.23 (1.53-3.26); occupational stress 1.39 (1.04- 1.86), 1.41 (1.06-1.89), 1.45(1.09-1.95), 1.48 (1.10-1.98); night shift days 1.58 (1.08-2.33), 1.66 (1.12-2.47), 1.55 (1.04-2.31), 1.76 (1.17-2.64). The results of the environmental risk score showed that the risk of carotid atherosclerosis increased with the increase of ERS (ERS trend text χ(2)=51.61, P<0.01); RCS results showed that there was a linear relationship between ERS and CAS in steel workers(P<0.01). Linear dose-response relationship existed between ERS and CAS (nonlinear test P>0.05). Conclusions: High temperature, noise, occupational stress and night shift days were related to carotid atherosclerosis. Linear dose-response relationship existed between ERS and CAS in steel workers.


Subject(s)
Carotid Artery Diseases , Metal Workers , Occupational Diseases , Occupational Exposure , Carotid Artery Diseases/epidemiology , Case-Control Studies , Humans , Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Risk Factors
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(6): 929-933, 2020 Jun 10.
Article in Chinese | MEDLINE | ID: mdl-32564562

ABSTRACT

Objective: To investigate the prevalence of pre-diabetes mellitus (PDM) and the impact of occupation-related factors on PDM, among workers from a steel company in Tangshan city, Hebei province. Methods: Clustering sampling method was used to select a steel company and to carry out occupational health-related physical checkup programs for eligible workers who had working in this company for longer than one year. The study began in February and ended up in June, 2017. Workers who were with FPG level as ≤6.9 mmol/L, and free from diabetes, were selected as the subjects for this study. Questionnaires were used and physical examinations and FPG testing conducted. Results: The total number of subjects in this study was 4 173, of which 2 648 appeared as pre-diabetic, with the prevalence rate as 63.4%. Increase of the PDM prevalence was in parallel with the length of service, among the workers. The risk for the pre-diabetes in those who worked more than 8 hours per day was 1.696 times higher than those who worked less than or equal to 8 h/d (95%CI:1.517-1.937). Compared with those workers without exposures to heat, noise or carbon monoxides, the proportion of pre-diabetes appeared higher in workers exposed to heat, noise or CO with OR=1.782 (95%CI: 1.205-2.636), 1.815 (95%CI: 1.209-2.794) and 1.653 (95%CI: 1.158-2.361), respectively. Risks for those who were exposed to heat or noise were higher than those who were free from exposure to any occupational hazards (OR=2.098, 95%CI: 1.296-3.397). Prevalence rates of pre-diabetes in those who were exposed to heat, noise or CO, were higher than that those who were not. Conclusion: Working hours and exposures to heat, noise or CO appeared as influential factors on PDM.


Subject(s)
Metallurgy , Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Prediabetic State/epidemiology , China/epidemiology , Humans , Iron , Steel
6.
Zhonghua Yi Xue Za Zhi ; 99(6): 447-452, 2019 Feb 12.
Article in Chinese | MEDLINE | ID: mdl-30786340

ABSTRACT

Objective: To evaluate the changes of rat renal function and cardiac function after transabdominal subtotal nephrectomy (STNx) and provide an ideal animal model for the study of chronic kidney disease (CKD) and cardiorenal syndrome (CRS). Methods: The SD rats (male, 5-6 weeks) were randomly divided into Sham group (n=10) and STNx group (n=10). The rats from Sham group underwent sham surgery, and the right nephrectomy plus the 2/3 left kidney artery ligation through abdominal incision were performed in the rats from STNx group. Twelve weeks after operation, the rat serum creatinine and renal pathology were examined, the size and fibrosis of cardiac cells were also observed, after the changes of cardiac function being detected by echocardiography. Results: Twelve weeks after the operation, STNx group rats were generally in poor condition, with a emaciated body, absorption of the renal infarct tissue, uneven surface, and residual renal tissue compensatory hypertrophy. The serum creatinine in Sham group and STNx group was (22.10±1.64) µmol/L and (52.80±3.34) µmol/L, respectively, and there was a statistically significant difference between the two groups (P<0.001). Compared with Sham group, the echocardiography results demonstrated that the thickness of left ventricular wall of rats from STNx group increased, the left ventricular volume decreased, and the diastolic and systolic function of left ventricular descended. The HE staining showed that the glomerulus, tubules and interstitial renal morphology were normal in Sham group, and glomerular sclerosis was observed in STNx group. And the Masson staining declared that the renal fibrous tissue distribution was normal in Sham group, and severe renal interstitial fibrosis was observed in STNx group. The wheat germ agglutinin (WGA) staining of myocardial tissue showed that myocardial cells in STNx group were larger than those in Sham group (1.293±0.060 vs 1.000±0.059, P<0.001). Moreover, the HE staining showed that there was partial myocardial tissue necrosis and fibrosis in STNx group, and severe myocardial fibrosis was observed in STNx group by Masson staining. Conclusion: Similar pathophysiological changes in human CKD were observed in the rats CKD model by transabdominal STNx, and the cardiac effects of this model make it an ideal choice to study CRS.


Subject(s)
Cardio-Renal Syndrome , Animals , Kidney , Male , Myocardium , Nephrectomy , Rats , Rats, Sprague-Dawley
7.
Zhonghua Gan Zang Bing Za Zhi ; 26(10): 756-764, 2018 Oct 20.
Article in Chinese | MEDLINE | ID: mdl-30481882

ABSTRACT

Objective: Hepatitis B surface antigen (HBsAg) loss is seldom achieved with nucleos(t)ide analog (NA) therapy in chronic hepatitis B patients but may be enhanced by switching to finite pegylated-interferon (Peg-IFN) alfa-2a. We assessed HBsAg loss with 48- and 96-week Peg-IFN alfa-2a in chronic hepatitis B patients with partial response to a previous NA. Methods: Hepatitis B e antigen (HBeAg)-positive patients who achieved HBeAg loss and hepatitis B virus DNA < 200 IU/mL with previous adefovir, lamivudine or entecavir treatment were randomized 1:1 to receive Peg-IFN alfa-2a for 48 (n = 153) or 96 weeks (n = 150). The primary endpoint of this study was HBsAg loss at end of treatment. The ClinicalTrials.gov identifier is NCT01464281. Results: At the end of 48 and 96 weeks' treatment, 14.4% (22/153) and 20.7% (31/150) of patients, respectively, who switched from NA to Peg-IFN alfa-2a cleared HBsAg. Rates were similar irrespective of prior NA or baseline HBeAg seroconversion. Among those who cleared HBsAg by the end of 48 and 96 weeks' treatment, 77.8% (14/18) and 71.4% (20/28), respectively, sustained HBsAg loss for a further 48 weeks. Baseline HBsAg < 1 500 IU/mL and week 24 HBsAg < 200 IU/mL were associated with the highest rates of HBsAg loss at the end of both 48- and 96-week treatment (51.4% and 58.7%, respectively). Importantly, extending treatment from 48 to 96 weeks enabled 48.3% (14/29) more patients to achieve HBsAg loss. Conclusion: Patients on long-term NA who are unlikely to meet therapeutic goals can achieve high rates of HBsAg loss by switching to Peg-IFN alfa-2a. HBsAg loss rates may be improved for some patients by extending treatment from 48 to 96 weeks, although the differences in our study cohort were not statistically significant. Baseline and on-treatment HBsAg may predict HBsAg loss with Peg-IFN alfa-2a.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis B Surface Antigens/immunology , Hepatitis B e Antigens/immunology , Hepatitis B, Chronic/drug therapy , Interferon alpha-2 , Interferon-alpha/therapeutic use , Polyethylene Glycols/therapeutic use , DNA, Viral , Hepatitis B, Chronic/immunology , Hepatitis B, Chronic/virology , Humans , Recombinant Proteins , Treatment Outcome
8.
Eur Rev Med Pharmacol Sci ; 21(11): 2725-2733, 2017 06.
Article in English | MEDLINE | ID: mdl-28678312

ABSTRACT

OBJECTIVE: Mounting evidence suggests the role of microRNAs (miRNAs) in regulating inflammatory responses in various vascular diseases. Inflammation is the key mechanism leading to atherosclerosis (AS) and various miRNAs are aberrantly expressed in response to AS pathophysiology. However, there are very limited studies that serve to elucidate the role of specific miRNA in in vivo or in vitro AS models. MATERIALS AND METHODS: Microarray analysis of blood plasma of apolipoprotein deficient (apoE-/-) mice was performed followed by the confirmation using qPCR. Bone marrow mononuclear cells (BMMCs), plasma, and vessel tissue were obtained from apoE-/- mice that were induced with miR-126 mimic or inhibitor. Ox-LDL-induced THP-1 macrophages served as in vitro AS model. The release of inflammatory cytokines was detected using ELISA. The regulatory effect of miR-126 on MAP3K10 was confirmed by luciferase reporter activity and immunohistochemical analyses. RESULTS: The results showed that the miR-126 exhibited a greater fold change of expression in AS mice. Further, the functional role of miR-126 in atherosclerosis pathophysiology was demonstrated both in vivo and in vitro. miR-126 reduced the cytokine release and also decreased the AS progression. miR-126 was also found to be involved in mitogen-associated protein kinase (MAPK) signaling pathway. MAP3K10 was identified to be a direct target. CONCLUSIONS: miR-126 might serve as a biomarker of AS and its over-expression might prevent the AS progression and development.


Subject(s)
Atherosclerosis/blood , MicroRNAs/blood , Mitogen-Activated Protein Kinases/metabolism , Animals , Apolipoproteins E/genetics , Atherosclerosis/genetics , Atherosclerosis/immunology , Biomarkers/blood , Cell Line, Tumor , Cytokines/metabolism , Disease Progression , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , MicroRNAs/genetics , Signal Transduction
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(11): 1468-1472, 2016 Nov 10.
Article in Chinese | MEDLINE | ID: mdl-28057136

ABSTRACT

Objective: To investigate the relationship between shift work and overweight/obesity in male steel workers. Methods: A questionnaire survey was conducted among the male steel workers selected during health examination in Tangshan Steel Company from March 2015 to March 2016. The relationship between shift work and overweight/obesity in the male steel workers were analyzed by using logistic regression model and restricted cubic splinemodel. Results: A total of 7 262 male steel workers were surveyed, the overall prevalence of overweight/obesitywas 64.5% (4 686/7 262), the overweight rate was 34.3% and the obesity rate was 30.2%, respectively. After adjusting for age, educational level and average family income level per month by multivariable logistic regression analysis, shift work was associated with overweight/obesity and obesity in the male steel workers. The OR was 1.19(95% CI: 1.05-1.35) and 1.15(95% CI: 1.00-1.32). Restricted cubic spline model analysis showed that the relationship between shift work years and overweight/obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ2=7.43, P<0.05). Restricted cubic spline model analysis showed that the relationship between shift work years and obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ2=10.48, P<0.05). Conclusion: Shift work was associated with overweight and obesity in the male steel workers, and shift work years and overweight/obesity had a nonlinear relationship.


Subject(s)
Obesity , Overweight , Cross-Sectional Studies , Humans , Logistic Models , Male , Prevalence , Risk Factors , Steel , Surveys and Questionnaires , Work Schedule Tolerance
10.
Genet Mol Res ; 14(4): 19309-16, 2015 Dec 29.
Article in English | MEDLINE | ID: mdl-26782583

ABSTRACT

The aim of this study was to provide the experimental basis for effective prevention and treatment of obliterative bronchiolitis (OB) by studying the changes on the microRNA (miRNA) expression profile after an orthotopic tracheal transplantation (OTT) simulating lung transplantation (LT). The OTT was performed on inbred rats to establish an OB animal model simulating LT, which was confirmed successful through pathological examination after 4 weeks. A miRNA microarray was used to screen for the most significantly differentially expressed miRNA in the OB tissues of donor transplanted trachea and real-time quantitative PCR was then used to validate the reliability of the microarray results. The microarray detection obtained 29 OB-related miRNAs, composed of 15 and 14 significantly up- and down-regulated miRNAs, respectively, among which miR-146a, miR-155, and miR-451, whose function is involved in the immune and inflammatory reactions, were subjected to relative quantitation research. The LT-simulated OTT-induced OB showed significantly differential expressions of multiple miRNAs, among which miR-146a and miR-155 were highly expressed, while miR-451 was lowly expressed, suggesting that these miRNAs may play an important regulatory role in the OB pathological process after LT.


Subject(s)
Bronchiolitis Obliterans/genetics , MicroRNAs/genetics , Trachea/transplantation , Animals , Bronchiolitis Obliterans/metabolism , Bronchiolitis Obliterans/pathology , Disease Models, Animal , Gene Expression Profiling , Gene Expression Regulation , Genetic Testing , Lung Transplantation , Male , MicroRNAs/metabolism , Oligonucleotide Array Sequence Analysis , Rats , Rats, Inbred Lew
11.
Eur Rev Med Pharmacol Sci ; 17(18): 2441-8, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24089221

ABSTRACT

OBJECTIVES: Heart failure is a major public health problem worldwide. However, the molecular mechanism is still unclear. This study aims to discover differentially expressed genes (DEGs) between non-ischemic or ischemic heart failure samples and healthy control, which may be used for diagnosis and treatment of heart failure. MATERIALS AND METHODS: Gene expression profile GSE9128 was downloaded from Gene Expression Omnibus, including 3 normal samples, 4 non-ischemic heart failure samples and 4 ischemic samples. Data processing and differential analysis were carried out with packages of R. Cluster analysis was also performed for all the samples to globally observe the difference among the three groups of samples. Interactors of the DEGs were retrieved with Osprey and then networks were constructed. The overlapping part of the network was selected out using Cytoscape, for which functional enrichment analysis was applied with DAVID tools. RESULTS: A total of 293 and 133 DEGs were obtained for non-ischemic and ischemic heart failure, respectively. Two networks were established and then functional enrichment analysis revealed that "regulation of programmed cell death" was most significantly over-represented in common DEGs. CONCLUSIONS: Genes differentially expressed in non-ischemic and ischemic heart failure can be biomarkers to distinguish the two types of heart failure. Besides, these genes can be targets to develop treatments.


Subject(s)
Computational Biology , Heart Failure/genetics , Oligonucleotide Array Sequence Analysis , Apoptosis Regulatory Proteins/genetics , Cluster Analysis , Humans , Membrane Proteins/genetics
12.
Nanoscale ; 4(9): 2958-61, 2012 Apr 28.
Article in English | MEDLINE | ID: mdl-22441701

ABSTRACT

We present a facile approach for the fabrication of a nanocomposite comprising α-Fe(2)O(3) nanotubes (NTs) anchored on reduced graphene oxide (rGO) for electrochemical capacitors (ECs). The hollow tubular structure of the α-Fe(2)O(3) NTs presents a high surface area for reaction, while the incorporation of rGO provides an efficient two-dimensional conductive pathway to allow fast, reversible redox reaction. As a result, the nanocomposite materials exhibit a specific capacitance which is remarkably higher (~7 times) than α-Fe(2)O(3) NTs alone. In addition, the nanocomposites show excellent cycling life and large negative potential window. These findings suggest that such nanocomposites are a promising candidate as negative electrodes in asymmetrical capacitors with neutral electrolytes.

13.
Phys Rev Lett ; 104(13): 137201, 2010 Apr 02.
Article in English | MEDLINE | ID: mdl-20481907

ABSTRACT

We demonstrate, both theoretically and experimentally, that cation vacancy can be the origin of ferromagnetism in intrinsic dilute magnetic semiconductors. The vacancies can be controlled to tune the ferromagnetism. Using Li-doped ZnO as an example, we found that while Li itself is nonmagnetic, it generates holes in ZnO, and its presence reduces the formation energy of Zn vacancy, and thereby stabilizes the zinc vacancy. Room temperature ferromagnetism with p type conduction was observed in pulsed laser deposited ZnO:Li films with certain doping concentration and oxygen partial pressure.

14.
J Phys Condens Matter ; 22(4): 046001, 2010 Feb 03.
Article in English | MEDLINE | ID: mdl-21386325

ABSTRACT

We address the room-temperature (RT) carbon ferromagnetism by considering the magnetic states of low-dimensional carbons linked by sp-hybridized carbon atoms. Based on the spin-polarized density functional theory calculations, we find that the sp(*) orbitals of carbon atoms can bring magnetic moments into different carbon allotropes which may eventually give rise to the long-range ferromagnetic ordering at room temperature through an indirect carrier-mediated coupling mechanism. The fact that this indirect coupling is Fermi-level-dependent predicts that the individual magnetism of diverse carbon materials is governed by their chemical environments. This mechanism may help to illuminate the RT magnetic properties of carbon-based materials and to explore the new magnetic applications of carbon materials.

15.
Nanotechnology ; 20(17): 175705, 2009 Apr 29.
Article in English | MEDLINE | ID: mdl-19420600

ABSTRACT

An effective surface-enhanced Raman scattering (SERS) template based on a 3D hybrid Ag nanocluster (NC)-decorated ZnO nanowire array was fabricated through a simple process of depositing Ag NCs on ZnO nanowire arrays. The effects of particle size and excitation energy on the Raman scattering in these hybrid systems have been investigated using rhodamine 6G as a standard analyte. The results indicate that the hybrid nanosystem with 150 nm Ag NCs produces a larger SERS enhancement factor of 3.2 x 10(8), which is much higher than that of 10 nm Ag NCs (6.0 x 10(6)) under 532 nm excitation energy. The hybrid nanowire arrays were further applied to obtain SERS spectra of the two-photon absorption (TPA) chromophore T7. Finite-difference time-domain simulations reveal the presence of an enhanced field associated with inter-wire plasmon coupling of the 150 nm Ag NCs on adjacent ZnO nanowires; such a field was absent in the case of the 10 nm Ag NC-coated ZnO nanowire. Such hybrid nanosystems could be used as SERS substrates more effectively than assembled Ag NC film due to the enhanced light-scattering local field and the inter-wire plasmon-enhanced electromagnetic field.

16.
Nano Lett ; 7(9): 2758-63, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17655269

ABSTRACT

We have clearly discriminated the single-, bilayer-, and multiple-layer graphene (<10 layers) on Si substrate with a 285 nm SiO2 capping layer by using contrast spectra, which were generated from the reflection light of a white light source. Calculations based on Fresnel's law are in excellent agreement with the experimental results (deviation 2%). The contrast image shows the reliability and efficiency of this new technique. The contrast spectrum is a fast, nondestructive, easy to be carried out, and unambiguous way to identify the numbers of layers of graphene sheet. We provide two easy-to-use methods to determine the number of graphene layers based on contrast spectra: a graphic method and an analytical method. We also show that the refractive index of graphene is different from that of graphite. The results are compared with those obtained using Raman spectroscopy.


Subject(s)
Graphite/chemistry , Materials Testing/methods , Nanostructures/chemistry , Nanostructures/ultrastructure , Photometry/methods , Refractometry/methods , Spectrum Analysis/methods , Macromolecular Substances/chemistry , Molecular Conformation , Nanotechnology/methods , Particle Size , Reproducibility of Results , Sensitivity and Specificity , Surface Properties
17.
J Chem Phys ; 124(20): 204703, 2006 May 28.
Article in English | MEDLINE | ID: mdl-16774360

ABSTRACT

Two-dimensional carbon nanowalls (CNWs) were prepared by microwave plasma-enhanced chemical-vapor deposition and scanning electron microscopy was used to observe their morphologies. The Raman observations of different sample orientations and polarizations show that CNWs are well crystallized. Micro-Raman scattering measurements were also carried out with different excitation laser lines (325, 488, 514, 532, and 633 nm). The D band shows a very strong shift of 46.19 cm(-1)eV with excitation laser energy and this has been explained by the double resonance effect. The decreasing intensity ratios IDIG and ID'/IG with increasing laser excitation energy were detected and discussed.

18.
Kaohsiung J Med Sci ; 16(8): 414-21, 2000 Aug.
Article in English | MEDLINE | ID: mdl-11221545

ABSTRACT

The purpose of this study is to evaluate whether there are pathobiologic differences and differences in overall rates survival between familial and non-familial breast cancer patients in Taiwan. A retrospective study was performed evaluating 76 familial breast cancer patients in 69 families, which included two BRCA1 related cases and six BRCA2 related cases. Patients were compared with 425 non-familial sporadic cases. Familial breast cancer patients had similar ages and stages as non-familial patients (mean, 46.6 years vs 48.9 years, p = 0.306). However, the familial breast cancer patients with BRCA1 and BRCA2 related cases presented at lower stages (p = 0.034) and younger ages than non-familial patients (mean, 45.1 years vs 48.9 years P = 0.042). The occurrence of infiltrating ductal carcinoma and lobular carcinoma in situ was not significantly different in the two groups. Mucinous carcinoma was represented with 6.7% (4/76) and 1.3% (1/76) medullary carcinoma. The overall grade of familial breast cancer, including BRCA1 and BRCA2 related cases in 8 infiltrating ductal carcinoma, was significantly higher than that of controls. The mean follow up was 4.5 years for familial breast cancers. Five- and 10-year overall survival rates were 69% and 61% for those with a family history, compared with 86% and 64% for those in the control group (p = 0.644). There were no statistically significant differences in disease-free survival rates between the two groups at 5 or 10 years (69% vs 78% in 5 years; 48% vs 58% in 10 years) (p = 0.862). Despite the younger ages and earlier stages at presentation in familial breast cancer patients with BRCA1 and BRCA2 related cases, the familial breast cancer patients had higher grade patholobiologic characteristics, but similar prognoses when compared with sporadic breast cancer patients. Owing to the limited number of familial cases in this study, more cases and longer follow up are needed.


Subject(s)
Breast Neoplasms/genetics , BRCA2 Protein/genetics , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Female , Follow-Up Studies , Genes, BRCA1 , Humans , Neoplasm Staging , Survival Rate
19.
Chin Med J (Engl) ; 106(6): 433-6, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8222895

ABSTRACT

Microsurgical tubocanalization was done in 412 patients. 278 women had the operation before the end of December 1987 and were followed up. The overall intrauterine pregnancy rate was 81.3% (92.86% for isthmus-isthmus anastomosis and 87.5% for ampulla-ampulla anastomosis). Two patients had ectopic pregnancy which was followed by term pregnancy subsequently. The factors affecting operative results were analyzed.


Subject(s)
Fallopian Tubes/surgery , Microsurgery , Sterilization Reversal/methods , Adult , Anastomosis, Surgical , Female , Follow-Up Studies , Humans , Sterilization, Tubal
20.
Contraception ; 38(6): 675-83, 1988 Dec.
Article in English | MEDLINE | ID: mdl-3219854

ABSTRACT

In a multicenter study taking place in four centers in Beijing (People's Republic of China), pregnancies up to 49 days of amenorrhea (DA) were interrupted with RU 486 (RU 38486, mifepristone, 600 mg orally once), followed 36-60 hours later by administration of dl-15-methyl-PGF 2 alpha-methyl ester (PG05, 1 mg vaginal suppository). One-hundred-and-sixty women were included in the study, three of whom being excluded from efficacy assessment because of non-compliance to the protocol. Complete pregnancy interruption without additional surgical procedure (success) was obtained in 136 women (86.6%, 95% confidence interval: 81.3-91.9%). The success rate was significantly (P = 0.013) higher for pregnancies below (91.3%), than for pregnancies above 42 days of amenorrhea (DA) (76.6%). The time elapsed between RU 486 intake and complete expulsion was 2.8 +/- 1.5 (sd) days (range: 1-12 days). Expulsion took place at the latest 4 days after RU 486 in 125 women (94.7%), and in 107 of these women, it occurred 3.1 +/- 1.7 (sd) hours after PG05 administration. Uterine bleeding occurred in all women after RU 486 intake whatever the outcome of treatment and lasted 11.5 +/- 4.8 (sd) days (range: 3-36 days). It was judged more or much more abundant than usual periods in 6.15% of the women. It led to a slight but significant decrease in hemoglobin as measured eight and 14 days after RU 486 intake. In five women, hemoglobin decreased by 4 g/dl or more, but no patient required a blood transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)


PIP: In a multicenter study taking place across 4 centers in Beijing, People's Republic of China, pregnancies of up to 49 days of amenorrhea (DA) were interrupted with RU486 (RU 38486, mifepristone, 600 mg, orally once), followed 36-60 hours later by administration of dl-15-methyl-PGF2alpha-methyl ester (PGO5, 1 mg vaginal suppository). 166 women were included in this study; however, 3 were excluded from efficacy assessment because of noncompliance to the protocol. Complete pregnancy interruption without additional surgical procedure (success) was obtained in 136 women (86.6%, 95% confidence interval; 81.3-91.9%). The success rate was significantly (P=0.013) higher for pregnancies below 91.3%), than for pregnancies greater than 42 DA (76.6%). The time elapsed between RU486 intake and complete expulsion was 2.8 +or- 1.5 SD days (range 1-12 days). Expulsion took place at the latest 4 days after RU486 in 125 women (94.7%), and in 107 of these women, it occurred 3.1 +or- 1.7 SD hours after PGO5 administration. Uterine bleeding occurred in all women after RU486 intake, whatever the outcome of treatment, and latest 11.5 +or- 4.8 SD days (range 3-36 days). It was considered that 6.15% of the women had more or much more abundant bleeding. It led to a slight but significant decrease in hemoglobin as measured both 8 and 14 days after RU486 intake. In 5 women, hemoglobin decreased by 4 g/dl or more, but no patient required a blood transfusion. The clinical and biological tolerance of the treatment was otherwise very satisfactory--mild to moderate pain was reported in approximately 80% of the women after PGO5 administration, and in approximately 20% of the patients, nausea, vomiting, and diarrhea were observed. These were usually moderate, although in 1 case, severe vomiting occurred after RU486 intake and necessitated vacuum aspiration before PGO5 administration. A moderate and transient increase in SGPT (to less than 1.5 times the upper normal limit) was noted in 3 women after RU486 and before PGO5, and in 5 women after both.


Subject(s)
Arbaprostil/pharmacology , Estrenes/pharmacology , Pregnancy, Unwanted , Pregnancy , Prostaglandins E, Synthetic/pharmacology , Adult , Amenorrhea , China , Drug Evaluation , Drug Synergism , Female , Humans , Mifepristone
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