Biomedical subjects

Li Wang

Publications and source records attributed to Li Wang.

At least 379 records · Page 21Linked to original sources

PubMed2004

Clinical benefit of gemcitabine plus cisplatin 3-week regimen for patients with advanced non-small cell lung cancer: a prospective observational study.

BACKGROUND: Platinum-based chemotherapy has been proved effective in patients with advanced non-small cell lung cancer (NSCLC). This study evaluated the effectiveness and safety of first-line chemotherapy with gemcitabine plus cisplatin (GEM-Cis) 3-week regimen in routine care of Chinese patients with advanced NSCLC. METHODS: Two hundred and twenty-one patients with NSCLC stage IIIb or IV were enrolled and 209 were eligible for effectiveness and safety analysis. The median age was 58 (range 29 to 79) years. The percents of cases in stage IV and stage IIIb were 52.2% and 47.8%; of Karnofsky performance score (KPS) less than 80 and 80 - 100 were 37.3% and 62.7% and of adeno-cancer and non-adeno-cancer were 59.8% and 40.2%. The average number of completed chemotherapy cycles was three. Measures of effectiveness included clinical benefit, significant clinical response (SCR) and adverse effects of GEM-Cis in the treatment of NSCLC at stages IIIb/IV. RESULTS: KPS increased from 79 +/- 9 at baseline to 86 +/- 10 after chemotherapy (P < 0.01). Lung cancer symptom scale (LCSS) score of pain, dyspnea and cough increased from 77 +/- 24, 74 +/- 22 and 63 +/- 19 to 92 +/- 15, 90 +/- 14 and 86 +/- 15, respectively (P < 0.01). The clinical benefit rate was 85.2% [95% confidence interval (CI) 80.3% - 90.0%]. The SCR was 89.5% (95% CI 85.3% - 93.7%). Median survival time was 7.8 months (95% CI 7.1 months-9.1 months). Sixty-four patients (30.6%) experienced an adverse effect that was deemed clinically significant. Only one patient (0.5%) was hospitalized due to chemotherapy related adverse effects. Life-threatening toxicity was observed in two patients (1.0%). CONCLUSION: First-line chemotherapy with GEM-Cis in the routine care of Chinese patients with advanced NSCLC is effective and safe.

Adult↗

PubMed2004

[Diagnosis and therapy of pneumocystosis complicated after renal transplantation].

OBJECTIVE: To investigate the early diagnosis, treatment and prevention of pneumocystosis complicated after renal transplantation. METHODS: Data from 12 cases of kidney transplant recipients who developed pneumocystosis were analyzed by clinical symptoms and signs, results of laboratory examination, imaging, bronchoscopy and biopsy. Combined TMP/SMZ was used for the prevention and treatment. RESULTS: Pneumocystis carinii (Pc) detection rate was 16.7% from alveolar douche, 66.7% with bronchoscopy and biopsy. Two cases was diagnosed by PCR method with sputum. Plain chest film showed 58.3% of lung cirrhosis. CT showed 50% frosted glass-like change in lungs and 25% with lung consolidation. Eleven cases were cured but one died. CONCLUSION: Pc detection by bronchoscopy and biopsy, and PCR are most helpful in the diagnosis of pneumocystosis complicated with renal transplantation, in addition to plain chest film and CT scaning. Combined TMP/SMZ is effective in the prevention and treatment of pneumocystosis.

Adolescent↗

PubMed2004

[Role of protein tyrosine phosphatase 1B in the type 2 diabetes and obesity].

PTP1B is a ubiquitously expressed intracellular protein tyrosine phosphatase. Several lines of evidence support an important role for protein tyrosine phosphatase 1B(PTP1B) in metabolism, and specially in type 2 diabetes and obesity. Overexpression of PTP1B protein has been observed in insulin-resistant states associated with obesity. PTP1B is a negative regulator of insulin and leptin signaling, PTP1B inhibitors might be efficacious in the treatment of type 2 diabetes and obesity by increasing insulin and leptin sensitivity.

Animals↗

PubMed2004

[A new ST segment analysis scheme for Holter system].

A new ST segment analysis scheme is developed for helping the doctors to browse the electrocardiogram (ECG) signals rapidly and then give a correct diagnosis. The preprocessing consists of baseline wander attenuation using median filter, high frequency noise rejection using order statistic filter, and then QRS complexes detection using wavelet analysis. In this paper, after the beginnings and the ends of the ST segments are mutually chosen by doctor, we compute the total deviations between ST segments and the modified baselines using mean value, and then plot the whole trend of the deviations. Doctors can browse the original ECG signals handily by our browsing system, and then give a diagnosis colligating other clinic features of the patient.

Electrocardiography, Ambulatory↗

PubMed2004

[Determination of orientin and vitexin in Trollius chinesis preparation by HPLC].

OBJECTIVE: To establish a HPLC method for determining orientin and vitexin in Trollius chinesis preparation. METHOD: The separation was carried out on Hypersil ODS column with a mixture of acetonitrile-1% acetic acid solution (15:85) as the mobile phase, at a flow rate of 1.0 mL x min(-1). The detection wavelength was set 340 nm. RESULT: Orientin showed a good linear relationship in the range of 8.42-84.2 microg x mL(-1) (r = 0.9999) and the average recovery is 98.3%, RSD is 0.8%. Vitexin showed a good linear relationship in the range of 8.07-80.7 microg x mL(-1) (r = 0.9999) and the average recovery is 102.4%. RSD is 1.7%. CONCLUSION: The method is sensitive, specific, and accurate with a good repeatability and can be used for the quality control of Trollius chinesis preparation.

Apigenin↗

PubMed2004

[Association between genetic factor and physical performance].

Correlation study between physical performance and gene has become a hot topic. Evidences have indicated that human capacity is partially influenced by genetic factors. Since 2000, the genetic studies of locomotion have progressed rapidly. More than 70 genetics markers associated with physical performance have been studied, such as VO(2max) (maximal oxygen uptake), muscle strength and lactate threshold. This research could be used to detect the special individual in spaceflight project and national defense project. Obviously, genetic detection of the special individual at early stage will save time and fund as compared with traditional training system. The present paper is to summarize some major international studies on aerobic exercise related genes and loci. We expect that the present article may provide helpful information to promote the project in China.

Humans↗

PubMed2004

Comparison of intraocular lens power calculation methods in eyes that have undergone laser-assisted in-situ keratomileusis.

PURPOSE: To compare methods of calculating intraocular lens (IOL) power for cataract surgery in eyes that have undergone myopic laser-assisted in-situ keratomileusis (LASIK). METHODS: Eleven eyes of eight patients who had previously undergone myopic LASIK (amount of LASIK correction, -5.50 +/- 2.61 D (SD); range, -8.78 to -2.38 D) and subsequently phacoemulsification with implantation of the SA60AT IOLs were included (refractive error after cataract surgery, -0.61 +/- 0.79 D; range, -2.0 to 1.0 D). We evaluated the accuracy of various combinations of (1) single-K versus double-K (in which pre-LASIK keratometry is used to estimate effective lens position) versions of the IOL formulas; the Feiz-Mannis method was also evaluated; (2) four methods for calculating corneal refractive power (clinical history, contact lens overrefraction, adjusted EffRP (EffRP(adj)), and Maloney methods); and (3) four IOL formulas (SRK/T, Hoffer Q, Holladay 1, and Holladay 2). The IOL prediction error was obtained by subtracting the IOL power calculated using various methods from the power of the implanted IOL, and the F test for variances was performed to assess the consistency of the prediction performance by different methods. RESULTS: Compared to double-K formulas, single-K formulas predicted lower IOL powers than the power implanted and would have left patients hyperopic in the majority of the cases; the Feiz-Mannis method had the largest variance. For the Hoffer Q and Holladay 1 formulas, the variances for EffRP(adj) were significantly smaller than those for the clinical history method (0.43 D2 vs 1.74 D2, P = .018 for Hoffer Q; 0.75 D2 vs 2.35 D2, P = .043 for Holladay 1). The Maloney method consistently underestimated the IOL power but had significantly smaller variances (0.19 to 0.55 D2) than those for the clinical history method (1.09 to 2.35 D2) (P < .015). There were no significant differences among the variances for the four formulas when using each corneal power calculation method. CONCLUSIONS: The most accurate method was the combination of a double-K formula and corneal values derived from EffRP(adj). The variances in IOL prediction error were smaller with the Maloney and EffRP(adj) methods, and we propose a modified Maloney method and second method using Humphrey data for further evaluation.

Adult↗

PubMed2004

[Measurement and analysis of optical constants of bulk ZnSe in THz region].

In the present paper the authors measured and analyzed the dispersion and absorption characteristics of the bulk ZnSe(110) in THz region using transmission THz time domain spectroscopy. After fitting the experiment data according to the Drude theory, the authors obtained the low-frequency dielectric constant and the high-frequency dielectric constant. The authors also observed the absorption by multi-phonon processes.

English Abstract↗

PubMed2004

[Photoluminescent and electroluminescent properties of a new rare earth terbium complex].

Pure green and narrowbandwidth emission from an organic electroluminescent device was presented by using arare earth terbium (III) complex as the emissive layer. The structure of the device was ITO/PVK/Tb/PBD/LiF/Al. It was proved that this new kind of rare earth complex has excellent photoluminescent and electroluminescent properties. The electroluminescent spectrum of the device was very similar to that of the terbium (III) complex film. The electroluminescent mechanism of the device was proposed by measuring and analyzing the spectra and electroluminescent property of the device. It is proposed that the excited carriers of PVK and PBD were captured by Tb3+ and light was emitted when the electrons and holes recombined at Tb3+.

Electrochemistry↗

PubMed2004

[Synthesis and spectroscopic analysis of complex alpha-Na7H[GaW9Fe3(H2O)3O37] x 16H2O].

Alpha-Na7H[GaW9Fe3(H2O)3O37] x 16H2O has been synthesized and it's IR, UV, ICP and XPS, have been studied. The IR spectrum exhibits nu(as)(w-o(a)-w), nu(as)(w-o(b)-w), nu(as)(w-o(c)-w) and nu(as)(w-o(d)-w) four peaks, which indicates that it has Keggin structure. The UV spectrum has two peaks, at 210 and 268 nm, corresponding to O(d)-W-->p pi-d pi and O(b)/O(c)-->p pi-d pi. O(b)/O(c)-->p pi-d pi is character peak. Both GaW9 and GaW9Fe3 have a 4 electrons reductive peaks, with E(1/2) of GaW9 minus even more, the GaW9Fe3 is alpha. Mössbauer spectrum has been studied. Effective magnetic moment is 6.00 x 10(-23) A x m2. The Mössbauer spectrum at 75 K shows an isomer shift delta = 0.43 mm x s(-1), within the range of 0.3 to 0.6 mm x s(-1) observed for high-spin iron(III) complexes. The authors found that title complex has antiferromagnetic properties. These kinds of heteropoly compounds have attracted our attention for the study of new materials.

English Abstract↗

PubMed2004

[Oil spill identification by near-infrared spectroscopy].

Petroleum oil spill happens occasionally at sea. It's important to differentiate the exact products in order to carry out following actions to decrease harmfulness. In the present study, a rapid oil spill identification method by near infrared spectroscopy coupled with pattern recognition techniques is proposed. 56 simulated spilled oils of gasoline, diesel fuel and lubricating oil in marine were chosen to develop the method. Organic reagent of CCl4 was used to extract the oil. Pattern recognition techniques were established by principal component analysis (PCA) coupled with Mahalanobis' distance with the multiplicative signal correction (MSC) and Norris first derivative pretreatment. The study shows that PCA technique is a useful method to extract the main characteristics, and Mahalanobis' distance is an ellipsoidal boundary that circumscribes a data cluster. And oil spill samples with concentration above 0.4 microL x mL(-1) can be successfully identified by the method. The developed technique could be further applied to the identification of spilled oil in marine.

Algorithms↗

PubMed2004

[Progress in type III secretion system].

Many Gram-negative bacteria use the type III secretion system (TTSS) to inject toxin proteins into host cells, then cause the plague disease, typhoid fever, diarrhea disease etc. Chaperone proteins is one of four components of MTSS and play an important role in helping the secretion of toxin proteins. Although these proteins had been found for almost ten years, the detailed function of chaperones is enigmatic. In this review, a brief introduction is given about the progress of classification, function of chaperones and characteristics of the interactions between chaperones and substrates.

Gram-Negative Bacteria↗

PubMed2003

A strategy for constructing a hybrid bilayer membrane based on a carbon substrate.

We construct a hybrid bilayer membrane (HBM) on a new substrate-carbon electrode. It is an extension of HBM based on other substrates. Primary alkylamine was chemically modified onto the surface of a carbon electrode by electrochemical scans; thus, a monolayer was formed on the electrode. Because the alkane chains section is toward the outside, a hydrophobic surface was constructed. Then a lipid monolayer was spread on the hydrophobic surface of the carbon electrode. The formed HBM was characterized by electrochemical and ATR-FT-IR methods. From ATR-FT-IR results, the lipid order parameter (S) of 0.73 was obtained. This kind of hybrid membrane has the advantages of a lipid/alkanethiol HBM. A potential application of this HBM as a biosensor (detecting K+) was given.

Journal Article↗

PubMed2003

Capillary array electrophoresis with confocal fluorescence rotary scanner.

A capillary array electrophoresis system with a rotary confocal fluorescence scanner is reported. A high speed direct current rotary motor, combined with a rotary encoder and a reflection mirror, has been designed to direct the excitation laser beam precisely to a round array of capillaries which are symmetrically distributed around the motor. The rotary encoder is introduced to accurately orientate the position of each capillary and its output signal triggers the data acquisition system to record the fluorescence signal corresponding to each capillary. Separation of enantiomers of glutamic acid, methionine and tryptophan with different additives are demonstrated by this system. The experimental results indicate that this setup can be used to optimize separation methods for capillary electrophoresis as quickly as possible.

Amino Acids↗

PubMed2003

A computational pipeline for protein structure prediction and analysis at genome scale.

MOTIVATION: Experimental techniques alone cannot keep up with the production rate of protein sequences, while computational techniques for protein structure predictions have matured to such a level to provide reliable structural characterization of proteins at large scale. Integration of multiple computational tools for protein structure prediction can complement experimental techniques. RESULTS: We present an automated pipeline for protein structure prediction. The centerpiece of the pipeline is our threading-based protein structure prediction system PROSPECT. The pipeline consists of a dozen tools for identification of protein domains and signal peptide, protein triage to determine the protein type (membrane or globular), protein fold recognition, generation of atomic structural models, prediction result validation, etc. Different processing and prediction branches are determined automatically by a prediction pipeline manager based on identified characteristics of the protein. The pipeline has been implemented to run in a heterogeneous computational environment as a client/server system with a web interface. Genome-scale applications on Caenorhabditis elegans, Pyrococcus furiosus and three cyanobacterial genomes are presented. AVAILABILITY: The pipeline is available at http://compbio.ornl.gov/proteinpipeline/

Algorithms↗

PubMed2003

Association study between late-onset Alzheimer's disease and the transferrin gene polymorphisms in Chinese.

To investigate the possible involvement of the transferrin (TF) gene polymorphism in the manifestation of Alzheimer's disease (AD), we analyzed the TF and apolipoprotein E (APOE) genotypes of 67 sporadic late-onset AD patients and 131 normal elderly controls in the Chinese population. Our data showed that the TF C1 homozygosity carriers had an increased risk of AD in subjects > or =75 years of age, showing that homozygosity for the TF C1 allele was associated with an approximately three-fold increased risk (OR=3.57, 95% CI, 1.24-10.27, P=0.014). No synergic effects were found between the APOE epsilon 4 allele and TF gene polymorphisms.

Age Factors↗

PubMed2003

Interaction of K7Fe3+P2W17O62H2 with supported bilayer lipid membranes on platinum electrode.

The influence of K(7)Fe(3+)P(2)W(17)O(62)H(2) on l-alpha-phosphatidylcholine/cholesterol bilayer lipid membrane on Pt electrode was studied by voltammetry and AC impedance spectroscopy. The interaction of the polyoxometalates with the BLM can promote the access of Ru(NH(3))(6)(3+) and [Fe(CN)(6)](3-/4-) to the electrode surface. It was found that some kind of pores had been formed on the BLM by AFM. The phenomenon is attributed to the interaction of K(7)Fe(3+)P(2)W(17)O(62)H(2) with phosphatidylcholine phosphate groups located in its outer leaflet. Experimental results are helpful to understand the biological activity of the polyoxometalates in vivo.

Animals↗

PubMed2003

EXCAVATOR: a computer program for efficiently mining gene expression data.

Massive amounts of gene expression data are generated using microarrays for functional studies of genes and gene expression data clustering is a useful tool for studying the functional relationship among genes in a biological process. We have developed a computer package EXCAVATOR for clustering gene expression profiles based on our new framework for representing gene expression data as a minimum spanning tree. EXCAVATOR uses a number of rigorous and efficient clustering algorithms. This program has a number of unique features, including capabilities for: (i) data- constrained clustering; (ii) identification of genes with similar expression profiles to pre-specified seed genes; (iii) cluster identification from a noisy background; (iv) computational comparison between different clustering results of the same data set. EXCAVATOR can be run from a Unix/Linux/DOS shell, from a Java interface or from a Web server. The clustering results can be visualized as colored figures and 2-dimensional plots. Moreover, EXCAVATOR provides a wide range of options for data formats, distance measures, objective functions, clustering algorithms, methods to choose number of clusters, etc. The effectiveness of EXCAVATOR has been demonstrated on several experimental data sets. Its performance compares favorably against the popular K-means clustering method in terms of clustering quality and computing time.

Algorithms↗