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For a generic n-degree polynomial system which contains n+1 polynomials in n variables, there are two classical resultant matrices, Sylvester resultant matrix and Cayley resultant matrix, lie at the two ends of a gamut of n+1 resultant... more
For a generic n-degree polynomial system which contains n+1 polynomials in n variables, there are two classical resultant matrices, Sylvester resultant matrix and Cayley resultant matrix, lie at the two ends of a gamut of n+1 resultant matrices. This paper gives the construction of the n–1 resultant matrices which lie between the two pure resultant matrices by the combined method
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Research Interests: Adolescent, Humans, Female, Young Adult, Clinical Sciences, and 4 moreAged, Middle Aged, Adult, and Capsid Protein
Hydroxyapatite coating on metal implants is an effective method to enhance bioactive properties of the metal surface. We report here a method to coat the Ti-6Al-4V alloy with hydroxyapatite crystals. After alkaline/heat treatment, the... more
Hydroxyapatite coating on metal implants is an effective method to enhance bioactive properties of the metal surface. We report here a method to coat the Ti-6Al-4V alloy with hydroxyapatite crystals. After alkaline/heat treatment, the spontaneous growth of organoapatite on titanium alloy surface involves sequential preadsorption of titanium isopropoxide (TIPO) and the copolymer of acrylic acid and itaconic acid on the metal, followed by exposure to simulated body fluid (SBF). The organoapatite characterization of the coating was carried out by scanning electron microscopy, energy dispersive spectrometer, and X-ray diffraction. The copolymer of acrylic acid and itaconic acid overlayer which is rich of carboxylate groups can lead to the deposition of needle-like and homogeneous HA on the surface after immersion in SBF.
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Urban soil Pb contamination is a great human health risk. Lead distribution and source in topsoils from 14 parks in Shanghai, China were investigated along an urban–rural gradient. Topsoils were contaminated averagely with 65 mg Pb kg−1,... more
Urban soil Pb contamination is a great human health risk. Lead distribution and source in topsoils from 14 parks in Shanghai, China were investigated along an urban–rural gradient. Topsoils were contaminated averagely with 65 mg Pb kg−1, 2.5 times higher than local soil background concentrations. HCl-extracts contained more anthropogenic Pb signatures than total sample digests as revealed by the higher 207/206Pb and 208/206Pb
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Polyether-bridged dihydroxamic acids and their mono- and binuclear copper(II), and cobalt(II) complexes have been synthesized and employed as models to mimic hydrolase in the catalytic hydrolysis of p-nitrophenyl picolinate (PNPP). The... more
Polyether-bridged dihydroxamic acids and their mono- and binuclear copper(II), and cobalt(II) complexes have been synthesized and employed as models to mimic hydrolase in the catalytic hydrolysis of p-nitrophenyl picolinate (PNPP). The kinetics and the mechanism of PNPP hydrolysis have been investigated. The kinetic mathematical model of PNPP cleavage by the complexes has been proposed. The effects of the different central
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Spectroscopic and viscosity methods were applied to investigate the mechanism of interaction between Congo red (CR)–Sm(III) complex and herring sperm DNA by using acridine orange as a spectral probe in Tris-HCl buffer (pH 7.40). The... more
Spectroscopic and viscosity methods were applied to investigate the mechanism of interaction between Congo red (CR)–Sm(III) complex and herring sperm DNA by using acridine orange as a spectral probe in Tris-HCl buffer (pH 7.40). The binding ratio of Sm(III)(CR)3 : DNA is 5 : 1, the apparent molar absorptivity of ϵSm(III)(CR)3–DNA is 4.80 × 10 L (mol cm) and the bonding constant of Sm(III)(CR)3 interacting with DNA is = 1.11 × 10 L mol.
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Research Interests:
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The objective of this study is to detect the infection of human papillomavirus (HPV) and the expression of p16(INK4a) in cervical lesions and to investigate the interaction between hrHPV and p16(INK4a) for cervical lesions and its... more
The objective of this study is to detect the infection of human papillomavirus (HPV) and the expression of p16(INK4a) in cervical lesions and to investigate the interaction between hrHPV and p16(INK4a) for cervical lesions and its diagnostic efficiency. hrHPV-DNA was detected by the hybrid capture II (HC-II) system. Immunochemical method was used to detect the expression of p16(INK4a), and histopathologic test was performed to identify cervical lesions. χ(2) test and Spearman's rank correlation were used for statistical analysis. Additive effects model was used to analyze the interaction. The diagnostic sensitivity, specificity, positive predictive values, negative predictive values, accuracy, and the area under the receiver operating characteristic curve were calculated with SPSS 13.0. hrHPV and p16(INK4a) positive rate increased (P < 0.05) with histopathologic diagnosis increasing. The positive rates of hrHPV and p16(INK4a) in negative or chronic inflammation were statistic...
Research Interests: Statistical Analysis, Adolescent, HUMAN PAPILLOMAVIRUS, Humans, Medical Oncology, and 13 moreFemale, Squamous Cell Carcinoma, Young Adult, Middle Aged, Adult, Diagnostic Accuracy, Chronic Inflammation, Indexation, Protein Binding, Cervical Intraepithelial Neoplasia, Early Diagnosis, Positive predictive value, and Rank Correlation
This paper discusses two problems: one is some important theories and algorithms of affine bracket algebra; the other is about their applications in mechanical theorem proving. First we give some efficient algorithms including the... more
This paper discusses two problems: one is some important theories and algorithms of affine bracket algebra; the other is about their applications in mechanical theorem proving. First we give some efficient algorithms including the boundary expanding algorithm which is a key feature in application. We analyze the characteristics of the boundary operator and this is the base for the implementation
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To investigate the clinical and genetical characteristics of a Chinese family with an autosomal-dominant inherited high-frequency sensorineural hearing loss. Pedigree was drawn after investigation. Fifeteen family members were checked up,... more
To investigate the clinical and genetical characteristics of a Chinese family with an autosomal-dominant inherited high-frequency sensorineural hearing loss. Pedigree was drawn after investigation. Fifeteen family members were checked up, and detailed audiological examination was performed. The proband of the kindred had been diagnosed with senserineural hearing loss. A Chinese family SX-G087 with non-sysdromic hearing loss was ascertained. The inheritance pattern of this family is autosomal dominant based on the investigated information. The affected members showed postlingual, progressive, bilateral moderate to severe sensorineural hearing impairment. The age of onset varied from 20 to 35 years. The hearing loss began at high frequencies, and lower frequencies became involved with increasing age. Pedigree analysis suggested an autosomal-dominant inheritance pattern in this family. The information should facilitate linkage analysis and positional cloning for the causative gene of t...
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To analyze the clinical and genetic features of a patient with Treacher Collins syndrome (TCS), and identify the mutation in TCOF1 gene. The medical history was taken, and general physical examinations and otological examinations were... more
To analyze the clinical and genetic features of a patient with Treacher Collins syndrome (TCS), and identify the mutation in TCOF1 gene. The medical history was taken, and general physical examinations and otological examinations were conducted in this patient. Genomic DNA was extracted from this patient and his parents and complete TCOF1 gene coding exons were amplified by specific PCR primers. Direct sequencing was carried out to identify the mutations. The raw data was analyzed with GeneTool software and molecular biological website. We detected a heterozygous c. 1639 delAG mutation in exon 11 of TCOF1, which resulted in a truncated protein lacking normal function. This mutation is a novel mutation and the second case identified in exon 11 of in TCS. TCS patient reported in this study has unique clinical phenotype. TCOF1 gene mutation is the specific risk factor.
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Research Interests:
A series of novel hydroxamic acid complexes (ML21 ~ ML23, M=CoII, MnIIICl) containing benzo-15-crown-5 and their analogues, ML24were successfully synthesized starting from benzo-15-crown-5 (B15C5) or 1,2-dimethoxybenzene. Their structures... more
A series of novel hydroxamic acid complexes (ML21 ~ ML23, M=CoII, MnIIICl) containing benzo-15-crown-5 and their analogues, ML24were successfully synthesized starting from benzo-15-crown-5 (B15C5) or 1,2-dimethoxybenzene. Their structures were characterized by 1H-NMR, IR, and MS as well as by elemental analysis. Moreover, the saturated oxygen uptake of their cobalt(II) complexes,Col 21−Col24, in diethyleneglycol dimethyl ether was determined over the −5
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A hydroxamic acid (HL) containing benzo-15-crown-5 and their copper(II), zinc(II), cobalt(II) and manganese(II) complexes have been synthesized and studied as catalysts for the cleavage of bis(4-nitrophenyl)phosphate (BNPP). The catalytic... more
A hydroxamic acid (HL) containing benzo-15-crown-5 and their copper(II), zinc(II), cobalt(II) and manganese(II) complexes have been synthesized and studied as catalysts for the cleavage of bis(4-nitrophenyl)phosphate (BNPP). The catalytic properties of these complexes and the kinetics and mechanism of BNPP hydrolysis have been investigated. The kinetic mathematical model of BNPP cleavage catalyzed by these complexes has been proposed. The effects
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The aims of this study were to explore the dose-response relationship between high-risk human papillomavirus (hrHPV) load and cervical lesions; the relationship between hrHPV viral load and the severity of cervical lesions; and the... more
The aims of this study were to explore the dose-response relationship between high-risk human papillomavirus (hrHPV) load and cervical lesions; the relationship between hrHPV viral load and the severity of cervical lesions; and the clinical application of the hybrid capture II (HC-II) system in the secondary prevention of cervical cancer. HrHPV viral load was detected by the HC-II system and cervical lesions were diagnosed from biopsied tissue. Curve estimation and Mantel trend analysis were used to explore the dose-response relationship between hrHPV viral load and cervical lesions. Spearman&amp;amp;amp;amp;amp;amp;#39;s rank correlation analysis and ordinal regression model were used for the analysis of hrHPV viral load and the severity of cervical lesions. Curve estimation showed good correlation between cervical lesion rates and hrHPV viral load (r=0.775, P=0.008); the rate of cervical lesions increased with hrHPV viral load (chi(trend)=8.000, P&amp;amp;amp;amp;amp;amp;lt;0.001). Medium intensity rank correlation was found between hrHPV viral load grades and the severity of cervical lesions (r(s)=0.321, P&amp;amp;amp;amp;amp;amp;lt;0.001); a correlation appeared between hrHPV viral load and the severity of cervical lesions (P&amp;amp;amp;amp;amp;amp;lt;0.001). These results suggest a dose-response relationship between hrHPV viral load and the severity of cervical lesions. This dependence has important clinical applications and shows the potential value of the HC-II system in cervical cancer prevention.
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In this paper, atomic force microscopy (AFM) has been used to investigate the morphology of monolayers of the amphiphilic rod-coil diblock molecule (EO7OPV) containing oligo(phenylene vinylene) dimer (OPV) and poly(ethylene oxide) (PEO)... more
In this paper, atomic force microscopy (AFM) has been used to investigate the morphology of monolayers of the amphiphilic rod-coil diblock molecule (EO7OPV) containing oligo(phenylene vinylene) dimer (OPV) and poly(ethylene oxide) (PEO) as well as the morphology of mixed monolayers of EO7OPV and palmitic acid (PA) deposited onto mica by the Langmuir-Blodgett technique. At surface pressures higher than 3 mN/m, EO7OPV forms regular-shaped aggregates with a monomolecular layer structure, where the hydrophilic PEO blocks are adsorbed onto the mica substrate and the hydrophobic OPV blocks form an ordered crystalline OPV layer on the top of the PEO layer through the strong pi-pi stacking interaction. In the mixed LB monolayers of EO7OPV and PA, the phase separation occurs. At a certain mixed ratio, EO7OPV molecules form rodlike domains with regular shape and uniform size at surface pressures higher than 3 mN/m. With the increase of the molar fraction of PA, the rodlike domains consisting of EO7OPV are elongated. The length of the rodlike domains can be tuned easily in a large range by altering the molar ratio of EO7OPV and PA. In addition, the rodlike domains are oriented to specific directions, corresponding to the directions of the potassium ion array on the mica surface having 6-fold symmetry. We demonstrate the possible formation mechanism and the elongation origin of rodlike domains in mixed LB monolayers and propose the two-step formation process of oriented rodlike domains deposited onto the mica substrate.
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In February 1998 Sergey Markelov [71 from the Moscow Center for Continuous Mathjematics Education sent a set of five geometric theorems to Dongming Wang for testing the capability of his GEOTHER package [8], with the aim of presenting a... more
In February 1998 Sergey Markelov [71 from the Moscow Center for Continuous Mathjematics Education sent a set of five geometric theorems to Dongming Wang for testing the capability of his GEOTHER package [8], with the aim of presenting a challenge to computer provers to prove really hard theorems. These theorems have been
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Human interleukin-8 (hIL-8) is a member of interleukin family which functions as a chemotactic factor as well as an angiogenesis mediator. Previously, a study reported that hIL-8 could be purified from inclusion bodies using a prokaryotic... more
Human interleukin-8 (hIL-8) is a member of interleukin family which functions as a chemotactic factor as well as an angiogenesis mediator. Previously, a study reported that hIL-8 could be purified from inclusion bodies using a prokaryotic expression system, however, the required re-naturation step limits the recovery of fully active protein. In this study, soluble recombinant hIL-8 was expressed as a secreted protein at high level in Pichia pastoris under the control of AOX1 (alcohol oxidase 1) promoter. A simple purification strategy was established to recover rhIL-8 from the fermentation supernatant. The process includes precipitation with 80% saturation ammonium sulfate and CM Sepharose ion exchange chromatography, yielding 30 mg/L purified rhIL-8 at over 95% purity. The obtained rhIL-8 displays high specific activity, stimulating the migration of mouse neutrophils at concentrations as low as 0.25 ng/mL. Our results demonstrate that P. pastoris expression system is an efficient tool for large-scale manufacture of active recombinant hIL-8 for various applications.
Research Interests: Humans, Mice, Animals, Pichia pastoris, Affinity chromatography, and 15 moreIon Exchange Chromatography, Solubility, Fermentation, Inclusion Bodies, Neutrophils, Molecular cloning, Protein expression and purification, Specific Activity, Large Scale, Pilot Projects, Recombinant Protein, Recombinant Proteins, Ammonium Sulfate, Biochemistry and cell biology, and Interleukin
Platelet-derived growth factors (PDGFs) are important biochemical mediators regulating many physiological and pathophysiological processes, including promotion of the chemotactic recruitment and proliferation of cells involved in wound... more
Platelet-derived growth factors (PDGFs) are important biochemical mediators regulating many physiological and pathophysiological processes, including promotion of the chemotactic recruitment and proliferation of cells involved in wound repair. Previously, homodimers of rhPDGF-AA protein were purified from Escherichia coli. However, eukaryotic proteins often contain posttranslational modifications, such as glycosylation, that are required for biological functions. In this study, an efficient method was established to purify a glycosylated rhPDGF-AA dimer from P. pastoris culture media by one step CM Sepharose ion exchange chromatography yielding about 20mg/L of over 95% highly purified rhPDGF-AA. Mass spectrometry analysis of the purified rhPDGF-AA displayed a molecular weight (MW) of 27,825.513Da, composed of a subunit with MW of 15,042.945Da and a subunit with MW of 12,904.374Da. The size difference is accounted for by differential glycosylation of the monomers. Biological activity of the rhPDGF-AA was confirmed by its ability to induce NIH/3T3 cells proliferation. The experimental procedure we have developed facilitates production of an active glycosylated rhPDGF-AA in large amounts for further research and drug development.
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We report a straightforward two-step synthesis toward conjugated DAD-type triblock copolymers with both electron-donor (D) and electron-acceptor (A) blocks. Cyano-substituted poly(phenylenevinylene) (CN−PPV) prepolymers with two bromide... more
We report a straightforward two-step synthesis toward conjugated DAD-type triblock copolymers with both electron-donor (D) and electron-acceptor (A) blocks. Cyano-substituted poly(phenylenevinylene) (CN−PPV) prepolymers with two bromide end groups hereby ...
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... Remark 5. It is necessary to point that in Example 3.3 we reduce the coupled KdV system by letting v = iu ... The nonlinear telephone equation [20] reads u tt − u xx + ut + αu+ βu 3 = 0, (4.46) which becomes the following ODE ...... more
... Remark 5. It is necessary to point that in Example 3.3 we reduce the coupled KdV system by letting v = iu ... The nonlinear telephone equation [20] reads u tt − u xx + ut + αu+ βu 3 = 0, (4.46) which becomes the following ODE ... (4.47) has the following factorization bracketleftbigg ∂ ξ ...
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ABSTRACT Synthesis and electronic properties of three swivel-cruciform oligothiophene dimers—bis(terthiophene) (BT3), bis(pentathiophene) (BT5) and bis(heptathiophene) (BT7)—with increased solubility in organic solvents are reported. We... more
ABSTRACT Synthesis and electronic properties of three swivel-cruciform oligothiophene dimers—bis(terthiophene) (BT3), bis(pentathiophene) (BT5) and bis(heptathiophene) (BT7)—with increased solubility in organic solvents are reported. We obtained a field-effect mobility of 3.7 × 10−5 cm2 V−1 s−1 and a current on/off ratio of &gt;103 for a solution-processed OFET device with dimer BT5 as p-type semiconductor.
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Three surveys were carried out in anchovy spawning periods in southern Yellow Sea in May and June 2001, and June 2002. Chlorophyll a (Chl-a) concentration, bacterioplankton abundance, biomass and their variations along the zone of tidal... more
Three surveys were carried out in anchovy spawning periods in southern Yellow Sea in May and June 2001, and June 2002. Chlorophyll a (Chl-a) concentration, bacterioplankton abundance, biomass and their variations along the zone of tidal fronts were investigated. The results showed that (1) high Synechococcus abundance distributed more often in frontal area and middle-surface layer of a stratified zone;
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In this paper, in situ atomic force microscopy has been used to investigate the micellization and self-assembling structure of an amphiphilic rod-coil block oligomer (EO16OPV) containing a conjugated oligo(phenylene vinylene) dimer and... more
In this paper, in situ atomic force microscopy has been used to investigate the micellization and self-assembling structure of an amphiphilic rod-coil block oligomer (EO16OPV) containing a conjugated oligo(phenylene vinylene) dimer and poly(ethylene oxide) at the mica-water interface. It is found that EO16OPV molecules have strong adsorption and aggregation properties on mica. In the wide concentration range from above the critical micelle concentration (cmc) to far below the cmc, a closely packed layer of stripe-like micelles with two preferred orientations can be formed at the mica-water interface. A cylindrical micelle structure for the stripes is proposed. We demonstrate that the stripe-like micelles formed on mica originate from different micellization processes at solution concentrations above and below the cmc. The origins of the strong micellization properties and oriented arrangement of the stripes are also discussed.
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This paper examines the influences of solvent evaporation and atmosphere humidity on self-assembling structures and thin-film microscopic morphologies of amphiphilic rod-coil block oligomers (EOnOPV) containing conjugated oligo(phenylene... more
This paper examines the influences of solvent evaporation and atmosphere humidity on self-assembling structures and thin-film microscopic morphologies of amphiphilic rod-coil block oligomers (EOnOPV) containing conjugated oligo(phenylene vinylene) dimer (OPV) coupled to poly(ethylene oxide) (PEO; n, the average number of ethylene oxides, is 16, 12, 7, and 3, respectively) on hydrophilic substrates. Atomic force microscopy (AFM), UV-vis absorption, and small angle X-ray diffraction are employed to investigate the thin-film morphology and structure. Solvent evaporation and atmosphere humidity are found to exert a strong influence on thin-film morphology and structure. Under the condition of quick evaporation and dry atmosphere, all EOnOPV oligomers form the monolayer islands. Increasing the solute volume, both EO16OPV and EO12OPV oligomers can form the polar lamellas with a head-to-tail packing arrangement. Under the condition of slow evaporation and humid atmosphere, EO16OPV and EO12OPV may self-assembly into curvy nanoribbons with well-defined width and curvature radii on mica, while EO7OPV and EO3OPV with the shorter PEO coils do not form. A symmetric bilayer structure for the ribbons is proposed. Plausible reasons for the variation in thin-film morphology are discussed, based on the results obtained from investigation of PEO coil length, solvent evaporation, and atmosphere humidity effects.
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Interleukin-3 (IL-3) is a hematopoietic growth factor involved in the survival, proliferation and differentiation of multipotent hematopoietic cells. A DNA fragment containing the mature human IL-3 sequence was cloned into pPICZαA,... more
Interleukin-3 (IL-3) is a hematopoietic growth factor involved in the survival, proliferation and differentiation of multipotent hematopoietic cells. A DNA fragment containing the mature human IL-3 sequence was cloned into pPICZαA, generating a fusion protein with the alpha factor signal sequence in the N-terminus and 6×His as well as c-Myc tags in the C-terminus. The resulting plasmid was integrated into the genome of Pichia pastoris strain X-33. Recombinant yeast transformants with high-level rhIL-3 production were identified, secreting as much as 26mg/L rhIL-3 after 4days of induction by methanol in flask. The rhIL-3 was purified by Ni(+)-NTA affinity chromatography, followed by DEAE anion exchange, yielding over 95% highly purified rhIL-3 preparation at about 21mg/L. Mass spectrometry and MALDI-TOF-TOF analysis of the purified rIL-3 showed molecular weights of 18995.694Da and 22317.469Da, due to different degrees of N-linked glycosylation. The biological activity of the rhIL-3 p...
Research Interests: Mass Spectrometry, Humans, Mice, Animals, Genetic transformation, and 16 morePichia pastoris, Plasmids, Affinity chromatography, Glycosylation, Fermentation, Molecular cloning, Protein expression and purification, Protein Expression, Molecular weight, Cell Proliferation, Biological activity, Growth Factor, Sperm Dna Fragmentation, Fusion Protein, Biochemistry and cell biology, and Interleukin
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We describe a novel polymerase chain reaction (PCR)-based gene amplification method utilizing a circularizable oligodeoxyribonucleotide probe (C-probe). The C-probe contains two target complementary regions located at each terminus and an... more
We describe a novel polymerase chain reaction (PCR)-based gene amplification method utilizing a circularizable oligodeoxyribonucleotide probe (C-probe). The C-probe contains two target complementary regions located at each terminus and an interposed generic PCR primer binding region. The hybridization of C-probe to a target brings two termini in direct apposition as the complementary regions of C-probe wind around the target to form a double helix. Subsequent ligation of the two termini results in a covalently linked C-probe that becomes &#39;locked on to&#39; the target. The circular nature of the C-probe allows for the generation of a multimeric single-stranded DNA (ssDNA) via extension of the antisense primer by Taq DNA polymerase along the C-probe and displacement of downstream strand, analogous to &#39;rolling circle&#39; replication of bacteriophage in vivo. This multimeric ssDNA then serves as a template for multiple sense primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex. Subsequent thermocycling denatures the dsDNA and initiates the next round of primer extension and ramification. This model results in significantly improved amplification kinetics (super-exponential) as compared to conventional PCR. Our results show that the C-probe was 1000 times more sensitive than the corresponding linear hemiprobes for detecting Epstein-Barr virus early RNA. The C-probe not only increases the power of amplification but also offers a means for decontaminating carryover amplicons. As the ligated C-probes possess no free termini, they are resistant to exonuclease digestion, whereas contaminated linear amplicons are susceptible to digestion. Treatment of the ligation reaction mixture with exonuclease prior to amplification eliminated the amplicon contaminant, which could also have been co-amplified with the same PCR primers; only the ligated C-probes were amplified. The combined advantages of the C-probe and thermocycling have a broad applicability for the detection of both DNA and RNA. Finally, we described a novel isothermal amplification method, ramification extension amplification, utilizing circular nature of C-probe and displacement activity of DNA polymerase.
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A DNA fragment containing the mature human interleukin (IL)-6 sequence was cloned into pPICZαA, generating a fusion protein with the alpha factor from baker&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s... more
A DNA fragment containing the mature human interleukin (IL)-6 sequence was cloned into pPICZαA, generating a fusion protein with the alpha factor from baker&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s yeast and integrated into the genome of Pichia pastoris strain X-33. Recombinant yeast transformants with high-level rhIL-6 production were identified, secreting as much as 280 mg L(-1) rhIL-6 after 4 days of induction by methanol. The rhIL-6 was purified by PEG-8000 precipitation, followed by DEAE anion exchange and Sephadex G-75 gel filtration, yielding over 95% pure rhIL-6 at about 170 mg L(-1) . Mass spectrometry analysis showed that the rhIL-6 has a molecular weight of 20,908.85 Da, which is close to the mass calculated from the sequence of the protein. Functional analysis of the purified rhIL-6 using the lymphocyte proliferation assay by an MTT [3-(4,5-dimethylthiazolyl-2)-2,5-diphenyl-tetrazoliumbromide] method demonstrated a specific activity that is at least fivefold higher than the commercial rhIL-6 produced in Escherichia coli. In summary, the experimental procedure we have reported here allows us to obtain a large amount of rhIL-6 from P. pastoris suitable for subsequent biophysical studies.
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ABSTRACT Water-soluble CdTenanocrystals are ultrafast synthesized in less than 10 s via the chemical aerosol flow method.
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We synthesize composite systems of multi-wall carbon nanotubes (MWCNTs)/SiO2 by using the sol-gel method. The dielectric properties of the systems with different-concentration MWCNTs are studied. In our MWCNTs/SiO2 inorganic systems, the... more
We synthesize composite systems of multi-wall carbon nanotubes (MWCNTs)/SiO2 by using the sol-gel method. The dielectric properties of the systems with different-concentration MWCNTs are studied. In our MWCNTs/SiO2 inorganic systems, the twin-percolation phenomenon exists when the concentrations of MWCNTs are 5-10% and 15-20%. The permittivity and conductivity have jumping changes. The twin-percolation phenomenon is attributed to the special transfer mechanism
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ABSTRACT Coverage controlled monolayer nano-sheets with homogeneous height were fabricated by casting aqueous solution of amphiphilic rod-coil diblock molecule 1 on mica surface. The monolayer sheet was anisotropic, due to the asymmetric... more
ABSTRACT Coverage controlled monolayer nano-sheets with homogeneous height were fabricated by casting aqueous solution of amphiphilic rod-coil diblock molecule 1 on mica surface. The monolayer sheet was anisotropic, due to the asymmetric arrangement of the diblock molecule on Surface, confirmed by polarization-dependent fluorescence spectra.
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New sterically encumbered N-heterocyclic carbene catalysts were synthesized and used to polymerize rac-lactide to give highly isotactic polylactide or meso-lactide to give heterotactic polylactide.
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Investigations on the role of oxygen in μc-Si:H films deposited with and without load lock chamber by VHF-PECVD technique have been reported in this paper. From the results of in-situ optical emission spectroscopy (OES), X-ray... more
Investigations on the role of oxygen in μc-Si:H films deposited with and without load lock chamber by VHF-PECVD technique have been reported in this paper. From the results of in-situ optical emission spectroscopy (OES), X-ray photoelectron spectroscopy (XPS) and Fourier transformation infrared absorption (FTIR) measurements, it can be identified that oxygen existing in μc-Si:H film with different bonding modes, namely
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Transplantation of encapsulated living cells is a promising approach for the treatment of a wide variety of diseases, especially diabetes. Range-scale application of the technique, however, is hampered by insufficient stability of the... more
Transplantation of encapsulated living cells is a promising approach for the treatment of a wide variety of diseases, especially diabetes. Range-scale application of the technique, however, is hampered by insufficient stability of the capsules. It is difficult to find the optimal membrane to meet all the properties required for cell transplantation. To overcome these difficulties, it is necessary to compare characteristics such as mechanical strength, cell proliferation and biocompatibility of different membranes. We prepared Ca-alginate-poly-L-lysine-alginate (APA) and Ba-alginate-poly-L-lysine-alginate (BPA) microcapsules using the electrostatic droplet method. The integrity of the microcapsules was measured by suspending them in a saline buffer and shaking at 150 rpm for 48 h. The microcapsules were cultured in simulated body fluid to analyze the osmotic pressure stability and implanted in the leg muscle pouch of SD rats to test in vivo transplantation stability. The microcapsules were implanted in the intraperitoneal cavity; then the biocompatibility of microcapsules was identified through analyzing fibrosis formation of microcapsules. The proliferation of cells (Cos-7 and HL-60) cultured in the microcapsules was measured by MTT assay. After 48 h shaking at 150 rpm, the percentages of intact microcapsules of BPA and APA microcapsules were 98.5 +/- 0.248% and 95.7 +/- 0.221% (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05), respectively. The intact percentages of APA and BPA microcapsules were 96.9% and 97.7%, respectively, after being soaked in SBF at 37 degrees C for 15 days. The empty APA and BPA microcapsules were not adhered to the muscle and there was light cellular overgrowth. There is no difference on biocompatibility in implantation into peritoneal cavities. After the cells were cultured in microcapsules, A(490 nm) of the 8th week was significantly higher than that of 1 day, and the 4th week was at the peak of the cell proliferation curve. After culture for 2 to 6 weeks, spheroids started to develop gradually within the beads. The mechanical strength of BPA microcapsules was higher than that of APA microcapsules. However, there was no difference between the two kinds of capsules in biocompatibility. Microencapsulation did not affect cell proliferation or increase the quantity of cells. In conclusion, BPA microcapsules were more suitable for transplantation in vivo.
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A term infant with hydrops fetalis presented with hypotonia, massive splenomegaly, renal failure, and severe hyperferritinemia. Multiple organ failure, myoclonus, and opisthotonus ensued and she died at 15 days of age. High rounded... more
A term infant with hydrops fetalis presented with hypotonia, massive splenomegaly, renal failure, and severe hyperferritinemia. Multiple organ failure, myoclonus, and opisthotonus ensued and she died at 15 days of age. High rounded forehead, large open fontanel, and a small recessed chin led to initial premortem diagnosis of Zellweger syndrome, but her plasma profile of long chain fatty acid was normal. Her subsequent clinical course and findings of postmortem examinations were consistent with perinatal lethal form of Gaucher&amp;amp;#39;s disease (PLGD). The diagnosis was confirmed by deficiency of enzyme beta-glucocerebrosidase in white blood cells and in cultured fibroblasts. In addition to the crossover features of Zellweger phenotype, this infant exhibited a number of unusual features including, severe hyperferritinemia, rapid progression of splenomegaly, and absence of icthyosis.