901
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Ye Y, Zhou K, Zhang B, Wang D, Wang J. High-Performance Repetitive Control of PWM DC-AC Converters With Real-Time Phase-Lead FIR Filter. ACTA ACUST UNITED AC 2006. [DOI: 10.1109/tcsii.2006.875383] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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902
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Zhao M, Wu PH, Zeng YX, Xia JC, Zhang FJ, Xian LJ, Zhang YP, Zhou K, Fan WJ, Zhang L, Gao F, Zhou QM. [Cytokine-induced killer cell fusion to lower recurrence of hepatocellular carcinoma after transcatheter arterial chemoembolization sequentially combined with radiofrequency ablation: a randomized trial]. ZHONGHUA YI XUE ZA ZHI 2006; 86:1823-8. [PMID: 17054858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
OBJECTIVE To ed evaluate the clinical effects of autologous cytokine-induced killer cell (CIK) fusion to lower recurrence of primary hepatocellular carcinoma (HCC) and the anti-hepatitis B virus (HBV) effect after transcatheter arterial chemoembolization (TACE) sequentially combined with radiofrequency ablation (RFA). METHODS Sixty-four HCC patients underwent TACE sequentially combined with RFA without residual tumor or extrahepatic metastasis were randomly divided into 2 groups: study group (n = 33), receiving autologous CIK fusion of the dose of (1.1 - 1.5) x 10(10) via the peripheral vein or hepatic artery, firstly once every 3 - 4 weeks for 4 times, and then once every 4 weeks for 4 times; and control group (n = 31). All patients were followed up for 1 year. RESULTS In the study group, 29 patients (29/33) were recurrence-free during the 1 year follow-up, 3 had recurrence in the liver 5, 6, and 7 months later respectively, and 1 patient had lymphoadenopathy in the hepatic portal 9 months later. In the control group, 23 patients (68.01%) were recurrence-free, 7 had recurrence in the liver within 1 year, and 1 had lung metastasis 11 months later. In the study group, the number of the patients with the HBV DNA content < 1 x 10(3) before treatment was 19, and increased to 29 after the treatment; 2 of the 19 patients who were HBsAg positive before the treatment became HBsAg negative after the treatment, and number of the patients with the HBV DNA content of 10(3) - 10(4) was 3 before the treatment, and became 13 after the treatment among which 1 patient had his HBV DNA content dropping from 1.6 x 10(7) to 1.6 x 10(4). In the control group, only 1 patient showed his HBV DNA content dropping from 1.1 x 10(5) to below 10(3). CONCLUSION Capable of reducing recurrence, prolonging the recurrence-free span, and attacking HBV, autologous CIK fusion after TACE sequentially combined with RFA is an effective novel therapeutic strategy for HCC.
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903
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Lambert-Falls R, Deutsch MA, Desch C, Zhou K, Perez E. Phase III adjuvant trial of concurrent epirubicin/taxane vs. sequential epirubicin/cyclophosphamide followed by taxane for node positive breast cancer. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.573] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
573 Background: This study evaluates whether concurrent epirubicin/taxane (ET) improves disease-free survival (DFS) at 3 yrs compared to the sequential combination of epirubicin/cyclophosphamide followed by a taxane (EC>T) in pts with operable node (+) breast cancer. Methods: Eligible pts were randomized to receive either ET (E 75 mg/m 2) for 8 cycles q21 days or EC>T (E 90 mg/m 2, C 600 mg/m2) for 4 cycles, followed by 4 cycles of a taxane q21 days. Choice of T (paclitaxel 175 mg/m2 or docetaxel 75 mg/m 2) was at the physician’s discretion. The primary endpoint is DFS. A 0.10 increase in the probability of DFS at 3 yrs for the ET arm would be considered clinically relevant. To detect 82 events, 300 subjects per arm are required to provide 90% power at 5% significance level. Results: 617 pts were enrolled from Nov 2000 to June 2003; 308 pts received ET and 309 pts received EC>T. Both treatment arms were well balanced with respect to age, nodal+, ER status, Her-2+ and PS; median age 52.5 (42%<50 years old); 70% ER+; 61% LN (1–3); 16% Her-2+; 87% PS 0. Total of 2206 cycles of treatment were given to ET compared 2314 cycles of treatment to EC>T. At 30 months of median follow-up there were DFS 102 events occurred; 47 events in ET arm (16%) and 55 events in EC>T arm (18%); 63 total deaths; 29 deaths in ET arm and 34 deaths in EC>T arm. The most common toxicities include alopecia (50%), fatigue (31%), nausea and vomiting (30%), dyspepsia (27%), febrile neutropenia (15%), constipation (12%), diarrhea (10%), arthralgia (11%), stomatitis (10%). In cardiac safety f/u, only one pt in ET arm remained LVEF drop >15. Conclusions: Epirubicin can be combined with taxanes in both sequential and concurrent therapies and both regimens are effective and well tolerated. The study is sponsored by Pfizer Inc. No significant financial relationships to disclose.
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904
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Yang XQ, Zhou K, Qiu K, Zhao YM. Segregation of large granules from close-packed cluster of small granules due to buoyancy. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 73:031305. [PMID: 16605515 DOI: 10.1103/physreve.73.031305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Indexed: 05/08/2023]
Abstract
Segregation of large granules in a vibrofluidized granular bed with inhomogeneous granular number density distribution is studied by an event-driven algorithm. Simulation results show that the mean vertical position of large granules decreases with the increase of the density ration of the large granules to the small ones. This conclusion is consistent with the explanation that the net pressure due to the small surrounding particle impacts balances the large granular weight, and indict that the upward movement of the large granules is driven by the buoyancy. The values of temperature, density, and pressure of the systems are also computed by changing the conditions such as heating temperature on the bottom and restitution coefficient of particles. These results indicate that the segregation of large granules also happen in the systems with density inversion or even close-packed cluster of particles floating on a low-density fluid, due to the buoyancy. An equation of state is proposed to explain the buoyancy.
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905
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Zhou K, Du P, Wang L, Matsushita Y, Shi J, Guo B, Shum HY. Decorating surfaces with bidirectional texture functions. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2005; 11:519-28. [PMID: 16144249 DOI: 10.1109/tvcg.2005.78] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We present a system for decorating arbitrary surfaces with bidirectional texture functions (BTF). Our system generates BTFs in two steps. First, we automatically synthesize a BTF over the target surface from a given BTF sample. Then, we let the user interactively paint BTF patches onto the surface such that the painted patches seamlessly integrate with the background patterns. Our system is based on a patch-based texture synthesis approach known as quilting. We present a graphcut algorithm for BTF synthesis on surfaces and the algorithm works well for a wide variety of BTF samples, including those which present problems for existing algorithms. We also describe a graphcut texture painting algorithm for creating new surface imperfections (e.g., dirt, cracks, scratches) from existing imperfections found in input BTF samples. Using these algorithms, we can decorate surfaces with real-world textures that have spatially-variant reflectance, fine-scale geometry details, and surfaces imperfections. A particularly attractive feature of BTF painting is that it allows us to capture imperfections of real materials and paint them onto geometry models. We demonstrate the effectiveness of our system with examples.
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906
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Doudna JA, MacRae IJ, Zhou K. Structural basis for RNA-regulated gene expression. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305097485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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907
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Jia XL, Chen WZ, Zhou K, Wang ZB. Effects of low-intensity pulsed ultrasound in repairing injured articular cartilage. Chin J Traumatol 2005; 8:175-8. [PMID: 15896276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To investigate the effects of low-intensity pulsed ultrasound in repairing injured articular cartilage. METHODS Ten adult New Zealand rabbits with bilateral full-thickness osteochondral defects on the cartilage surface of intercondylar fossas were used in this study. The wounds in the left knees were treated with low-intensity pulsed ultrasound as the experimental group. The right knees received no treatment as the control group. All the animals were killed at 8 weeks after injury and the tissues in the wounds were collected for gross appearance grading, histological grading and proteoglycan quantity. RESULTS The scores of the gross appearance grades, histological grades and the optical density of toluidine blue of the tissues in the experimental group were significantly higher than those of the controls at 8 weeks after injury (P < 0.05). CONCLUSIONS Low-intensity pulsed ultrasound can accelerate the repair of injured articular cartilage.
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908
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Yang G, Yan J, Zhou K, Wei F. Sequence variation and gene duplication at MHC DQB loci of baiji (Lipotes vexillifer), a Chinese river dolphin. ACTA ACUST UNITED AC 2005; 96:310-7. [PMID: 15843636 DOI: 10.1093/jhered/esi055] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The major histocompatibility complex (MHC) is a fundamental part of the vertebrate immune system, and the high variability in many MHC genes is thought to play an important role in the recognition of parasites. Baiji (Lipotes vexillifer) is one of the most endangered species in the world. Its wild population has declined to fewer than 100 individuals and has a very high risk of becoming extinct in the near future. In this study we present a first step in the molecular characterization of a DQB-like locus of baiji by nucleotide sequence analysis of the polymorphic exon 2 segments. In the examined 172 bp sequences from a group of 18 incidentally captured or stranded individuals, 48 variable sites were determined and 43 alleles were identified, many of which were represented by only one clone. Three to seven alleles were found in each individual, suggesting gene duplications. No deletion, insertion, or exceptional stop codon was detected, suggesting these alleles function in vivo. Phylogenetic reconstruction using neighbor joining grouped the 43 alleles into two distinct lineages, differing by seven nucleotides and four amino acids. Substitutions of amino acids tend to be clustered around sites postulated to be responsible for selective peptide recognition. In the peptide-binding region (PBR) of the DQB locus, the average number of nonsynonymous substitutions per site is greater than that of synonymous substitutions per site (0.1962 versus 0.0256, respectively). Nucleotide and amino acid sequences both showed a relatively high level of similarity (nucleotides 90.6%; amino acids 80.6%) to those of beluga whale (Delphinapterus leucas) and narwhal (Monodon monoceros). The high level of baiji MHC polymorphism revealed in the present study has not been reported in other cetaceans and could be a consequence of the small baiji population adapting to freshwater with a relatively high level of pathogens.
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909
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Wang H, Hao B, Zhou K, Chen X, Wu S, Zhou G, Zhu Y, He F. Linkage Disequilibrium and Haplotype Architecture for two ABC Transporter Genes (ABCC1 and ABCG2) in Chinese Population: Implications for Pharmacogenomic Association Studies. Ann Hum Genet 2004; 68:563-73. [PMID: 15598215 DOI: 10.1046/j.1529-8817.2003.00124.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Information about linkage disequilibrium (LD) patterns and haplotype structures for candidate genes is instructive for the design and analysis of genetic association studies for complex diseases and drug response. ABCC1 and ABCG2 are genes coding for two multidrug resistance (MDR) associated transporters; they are also related to some pathophysiological traits. To pinpoint the LD profiles of these MDR genes in Chinese, we systemically screened 27 unrelated individuals for single nucleotide polymorphisms (SNPs) in the coding and regulatory regions of these genes, and thereby characterized their haplotype structures. Despite marked variations in haplotype diversity, LD pattern and intragenic recombination intensity between the two genes, both loci could be partitioned into several LD blocks, in which a modest number of haplotypes accounted for a high fraction of the sampled chromosomes. We concluded that each locus has its own genomic LD profile, but that they still share a common segmental LD architecture with low haplotype diversity. Our data will benefit genetic association studies of complex traits and drug response possibly related to these genes.
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910
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Zhou K, Chen WZ. [Inhalation chemotherapy for metastatic cancer in the lung]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 2004; 27:427-9. [PMID: 15256103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
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911
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912
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Dedes H, Zhou K, Moore AA. 89 IS DRINKING ASSOCIATED WITH DEVELOPMENT OF LESS DISABILITY IN OLDER PERSONS? J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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913
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Parker T, Adams D, Zhou K, Harris M, Yu L. Fatty Acid Composition and Oxidative Stability of Cold-pressed Edible Seed Oils. J Food Sci 2003. [DOI: 10.1111/j.1365-2621.2003.tb09632.x] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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914
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Bai WY, Shi WM, Zhou K. [Nutrition support of severe illness patients of general surgery during peroperation period]. ZHONGGUO WEI ZHONG BING JI JIU YI XUE = CHINESE CRITICAL CARE MEDICINE = ZHONGGUO WEIZHONGBING JIJIUYIXUE 2003; 15:117-9. [PMID: 12857477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
OBJECTIVE To study the clinical effect of the nutrition support of severe illness patients of general surgery during peroperation period. METHODS To analyse application of the nutrition support applied to 147 cases with severe illness of general surgery in peroperation period since 1995. In 147 cases, there were abdominal operations(n=138, 93.9%) and cervical operations(n=9, 6.1%) and emergency operations (n=63, 42.8%). Total parenteral nutrition (TPN) was used by venous canal ways including internal jugular vein (n=132, 89.8%), axillary vein (n=11, 7.5%), femoral vein (n=4, 2.7%), used unicameral catheter (n=127, 86.4%), double catheter (n=20, 13.6%), 41 cases were used enteral nutrition. Two different nutritional support treatments were employed, one was TPN-->parenteral nutrition(PN)+oral diet-->oral diet (n=106, 72.1%) and another was TPN-->PN+enteral nutrition(EN)-->EN-->EN+oral diet-->oral diet (n=41, 27.9%). RESULTS There were not complications of catheterization and metabolism in the nutrition support, 142 cases (96.6%) had been cured and 5 cases (3.4%) died of primary diseases after operation. CONCLUSION The nutrition support of patients with severe illness of general surgery in peroperation period is an important adjuvant treatment that can assure operative safety and promote recovery on postoperation.
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915
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Wu P, Zhou K, Zhang Z, Xu L. [Molecular genetic marker identification of traditional Chinese drug hippocampus]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2002; 33:226-33. [PMID: 11938969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Ancient DNA technique was used to extract DNA from 5 species of Chinese traditional drugs Hippocampus. The 12S rRNA gene fragment and cytochrome b gene fragment were amplified from DNA extract using Polymerase Chain Reaction (PCR) method. Restriction Fragment Length Polymorphism (RFLP) analysis and DNA sequence analysis were performed. The RFLP analysis method can identify 2 species of Hippocampus. The molecular genetic markers produced by DNA sequence method can identify all 5 species of Hippocampus. This method will be valuable for the identification of other animal drugs.
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916
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917
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Wu P, Zhou K, Xu L, Teng J. [Molecular identification of the Chinese drug turtle shells]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2002; 33:304-9. [PMID: 11939073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
This paper reports a new method to identify the Chinese drug turtle shells using PCR product direct sequencing method. DNA was extracted from tissues of the Chinese three-keeled pond turtle Chinemys reevesii and 20 other species of turtles occurring in China and Southeast Asian countries. One hundred and ten base pairs of mitochondrial 12S rRNA gene fragment were amplified from the extract using PCR technique and obtained sequences. These sequences were used to construct 12S rRNA gene fragment sequence database for the 21 turtle species. Comparison of these sequences indicated that the sequence from the Chinese three-keeled pond turtle is different from that of all the other 20 turtle species. The sequence divergence is 3.7-15.7%. DNA was extracted from 0.1-0.5 g of shell from 19 turtle shells provided by the Jiangsu Institute for Drug Control and 12S rRNA gene fragment was amplified and sequenced. Comparison of the sequences from the 19 turtle shells and 12S rRNA gene fragment sequence database indicated that only 3 samples are shells of the Chinese three-keeled pond turtle specified in the Phamacopoeia of the People's Republic of China and the others are substitutes. The technique used in the present paper was found to be effective and reliable for the identification of turtle shells.
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918
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Xie Q, Liu KD, Hu MY, Zhou K. SF/HGF-c-Met autocrine and paracrine promote metastasis of hepatocellular carcinoma. World J Gastroenterol 2001; 7:816-20. [PMID: 11854908 PMCID: PMC4695601 DOI: 10.3748/wjg.v7.i6.816] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the role of SF/HGF-Met autocrine and paracrine in met astasis of hepatocellular carcinoma (HCC).
METHODS: SF/HGF and c-met transcri ption and protein expression in HCC were examined by RT-PCR and Western Blot in 4 HCC cell lines, including HepG2, Hep3B, SMMC7721 and MHCC-1, the last cell line had a higher potential of metastasis. sf/hgf cDNA was transfected by the method of Lipofectin into SMMC7721. SF/HGF and c-met antibody were used to stimulate and block SF/HGF-c-met signal transduction. Cell morphology, mobility, and proliferation were respectively compared by microscopic observation, wound healing assay and cell growth curve.
RESULTS: HCC malignancy appeared to be relative to its met-SF/HGF expression. In MHCC-1, c-met expression was much stronger than that in other cell lines with lower potential of metastasis and only SF/HG F autocrine existed in MHCC-1. After sf/hgf cDNA transfection or conditioned medium of MHCC-1 stimulation, SMMC7721 changed into elongated morphology, and the abilities of proliferation (P < 0.05) and mobility increased. Such bio-activity could be blocked by c-met antibody (P < 0.05).
CONCLUSION: The system of SF/HGF-c- met autocrine and paracrine played an important role in development and metastas is potential of HCC. Inhibition of SF/HGF-c-met signal transduction system may reduce the growth and metastasis of HCC.
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919
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Zhao D, Dai Z, Zhou K, Zhang L. [Expression of the artificial cecropin CMIV-like gene of Chinese silkworm Bombyx mori in Laphygma exigua larvae]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 2001; 41:680-5. [PMID: 12552823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The synthesized CMIV-like Gene was linked with the signal peptide gene of nature silkworm antibacterial peptide and was inserted into baculovirus expression vector pFastBac 1, construcing a recombinant transposing vector. The vector was transformed into DH10Bac competent E. coli cells. The recombinant Bacmid was obtained. The recombinant Bacmid was transfected into sf21 cells to get the recombinant virus. Laphygma exigua larvae were infected with the recombinant virus to express the antibacterial peptide. The hemolymph were tested to have antibacterial activity. The active antibacterial peptide was purified by acid polyacrylamide electrophoresis. The specific expression of mRNA of CMIV-like Gene was tested using Northern blotting.
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920
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Gong Q, Zhou K. [Study on relationship between the reflux laryngitis and gastroesophageal reflux disease]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2001; 15:548-9. [PMID: 12541725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To investigate the relationship between reflux laryngitis and gastroesophageal reflux disease (GRED). METHOD 130 Patients of refractory chronic laryngitis with upper endoscopy and ambulatory 24-hr esophageal pH-metry. The patients of gastroesophageal reflux disease were divided into two groups. Group A was treated with antacids and motile medications. Group B was control. RESULT 45 (34.6%) gastroesophageal reflux disease were found in 130 cases. 21 cases(91.3%) were healed in group A. 3 of 22 cases (13.6%) were healed in control (P < 0.01). CONCLUSION The gastroesophageal reflux disease was an important cause of the reflux laryngitis which symptoms and signs can be healed by antacids and motile medications.
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921
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Zeng HH, Tu PF, Zhou K, Wang H, Wang BH, Lu JF. Antioxidant properties of phenolic diterpenes from Rosmarinus officinalis. Acta Pharmacol Sin 2001; 22:1094-8. [PMID: 11749806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
AIM To investigate the inhibition capacities of carnosol, rosmanol, and epirosmanol, which are phenolic diterpenes from Rosmarinus officinalis, to oxidized low-density lipoprotein (LDL) formation in human blood and detect their scavenging activities to lipid free radical and superoxide anion in vitro. METHODS The antioxidant activities which were expressed with the inhibilities to lipid free radicals in the membrane lipid of cell and oxidized LDL formation were evaluated by TBARS assay and ESR method. The inhibition on the Cu2+-mediated oxidization of apo B formation in LDL was investigated by fluorescence spectroscopy. RESULTS Carnosol, rosmanol, and epirosmanol had an inhibitory activity to lipid peroxidation and oxidized apo B formation in human bloods LDL. The IC50 were 7-10 micromol/L. The antioxidant mechanism was related to the scavenging activities to lipid free radical. CONCLUSION carnosol, rosmanol, and epirosmanol showed the activity in inhibiting LDL oxidation.
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922
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Lupták A, Ferré-D'Amaré AR, Zhou K, Zilm KW, Doudna JA. Direct pK(a) measurement of the active-site cytosine in a genomic hepatitis delta virus ribozyme. J Am Chem Soc 2001; 123:8447-52. [PMID: 11525650 DOI: 10.1021/ja016091x] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hepatitis delta virus ribozymes have been proposed to perform self-cleavage via a general acid/base mechanism involving an active-site cytosine, based on evidence from both a crystal structure of the cleavage product and kinetic measurements. To determine whether this cytosine (C75) in the genomic ribozyme has an altered pK(a) consistent with its role as a general acid or base, we used (13)C NMR to determine its microscopic pK(a) in the product form of the ribozyme. The measured pK(a) is moderately shifted from that of a free nucleoside or a base-paired cytosine and has the same divalent metal ion dependence as the apparent reaction pK(a)'s measured kinetically. However, under all conditions tested, the microscopic pK(a) is lower than the apparent reaction pK(a), supporting a model in which C75 is deprotonated in the product form of the ribozyme at physiological pH. While additional results suggest that the pK(a) is not shifted in the reactant state of the ribozyme, these data cannot rule out elevation of the C75 pK(a) in an intermediate state of the transesterification reaction.
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923
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Yan F, Zhou K, Shen J. [Comparison of enhancement patterns of multi-phase scan of dynamic MRI and dynamic CT in small hepatocellular carcinoma]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2001; 23:413-6. [PMID: 11810775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To study prospectively the enhancement features of multi-phase scan of dynamic MRI and spiral CT in the diagnosis of small hepatocellular carcinoma (SHCC) and to discuss the cause of dynamic MRI being superior to spiral CT. METHODS Multi-phase contrast scanning of dynamic MR and spiral CT were done in 53 SHCC patients. The lesions were proved by surgery and pathology. The arterial-phase, portal venous-phase and delayed phase scan of spiral CT were carried out after the pre-contrast scanning of the entire liver. MRI was performed with SE sequence and FMPSPGR sequence dynamic multi-phase contrast scans. RESULTS Seventy-six lesions were found in 53 patients. Sixty-nine lesions and 54 lesions were enhanced obviously in MR and spiral CT arterial-phase scans. The typical enhancement patterns of SHCC in the arterial-phase, portal venous-phase and delayed phase scan of MRI and spiral CT were hyper-hypo-hypointense (dense) and hyperintense (hyperdense), -isointense (isodense) and -hypointense (hypodense). Atypical enhancement patterns were hyperintense (hyperdense), -hyperintense (hyperdense), -hyperintense (hyperdense), -hyperintense (hyperdense), -isointense (isodense), -isointense (isodense) and -hypointense- (hypodense), -hypointense (hypodense) and -hypointense (hypodense). CONCLUSION Both dynamic MRI and spiral CT multi-phase contrast scanning are able to demonstrate the enhancement features of SHCC, with arterial-phase scan of MRI being superior to spiral CT in reflecting the hypervascular characterization of SHCC. Combined with SE sequence in characterizing the SHCC, MRI is better than spiral CT.
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924
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Yu Y, Zhang C, Zhou G, Wu S, Qu X, Wei H, Xing G, Dong C, Zhai Y, Wan J, Ouyang S, Li L, Zhang S, Zhou K, Zhang Y, Wu C, He F. Gene expression profiling in human fetal liver and identification of tissue- and developmental-stage-specific genes through compiled expression profiles and efficient cloning of full-length cDNAs. Genome Res 2001; 11:1392-403. [PMID: 11483580 PMCID: PMC311073 DOI: 10.1101/gr.175501] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Fetal liver intriguingly consists of hepatic parenchymal cells and hematopoietic stem/progenitor cells. Human fetal liver aged 22 wk of gestation (HFL22w) corresponds to the turning point between immigration and emigration of the hematopoietic system. To gain further molecular insight into its developmental and functional characteristics, HFL22w was studied by generating expressed sequence tags (ESTs) and by analyzing the compiled expression profiles of liver at different developmental stages. A total of 13,077 ESTs were sequenced from a 3'-directed cDNA library of HFL22w, and classified as follows: 5819 (44.5%) matched to known genes; 5460 (41.8%) exhibited no significant homology to known genes; and the remaining 1798 (13.7%) were genomic sequences of unknown function, mitochondrial genomic sequences, or repetitive sequences. Integration of ESTs of known human genes generated a profile including 1660 genes that could be divided into 15 gene categories according to their functions. Genes related to general housekeeping, ESTs associated with hematopoiesis, and liver-specific genes were highly expressed. Genes for signal transduction and those associated with diseases, abnormalities, or transcription regulation were also noticeably active. By comparing the expression profiles, we identified six gene groups that were associated with different developmental stages of human fetal liver, tumorigenesis, different physiological functions of Itoh cells against the other types of hepatic cells, and fetal hematopoiesis. The gene expression profile therefore reflected the unique functional characteristics of HFL22w remarkably. Meanwhile, 110 full-length cDNAs of novel genes were cloned and sequenced. These novel genes might contribute to our understanding of the unique functional characteristics of the human fetal liver at 22 wk.
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925
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Zhang Y, Liu H, Zhou K. Lack of correlation of vacA genotype, cagA gene of Helicobacter pylori and their expression products with various gastroduodenal diseases. Chin Med J (Engl) 2001; 114:703-6. [PMID: 11780331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To investigate the correlation among vacA genotypes, cagA gene, VacA, serum CagA antibodies of Helicobacter pylori (H. pylori) and gastroduodenal diseases. METHODS vacA genotypes and cagA gene of 62 H. pylori strains isolated from patients with chronic gastritis, peptic ulcer and gastric cancer were tested by polymerase chain reaction, and Hela cell assay for VacA activity in vitro. Serum CagA antibodies were measured by EIA method in the same patients. RESULTS All 62 H. pylori strains possessed the vacA gene and vacA genotypes of all strains were type s1a/m2. Total positive rate of cagA gene was 56.45%; the positive rates of cagA gene of H. pylori strains isolated from patients with chronic gastritis, peptic ulcer and gastric cancer were 55.56%, 54.17% and 63.64%, respectively (P > 0.05). The total positive rate of VacA was 37.10%; the positive rates of VacA produced by H. pylori strains isolated from patients with chronic gastritis, peptic ulcer and gastric cancer were 33.33%, 29.17% and 63.64%, respectively (P > 0.05). The positive rates of CagA antibodies in patients with chronic gastritis, peptic ulcer and gastric cancer were 70.37%, 79.17% and 40.00%, respectively (P > 0.05). The total positive rate of CagA antibodies was 68.85%. CONCLUSION There was no correlation among cagA gene and vacA genotypes of H. pylori, VacA, serum CagA antibodies and various gastroduodenal diseases.
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926
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Zhang Y, Chen Y, Zhou K, Cai K. [Mitochondrial mechanisms of CPT-induced apoptosis in nasopharyngeal carcinoma cells]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2001; 15:309-10. [PMID: 12541789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To understand whether CPT-induced apoptosis is related to the alteration of mitochondrial transmembrane potentials (delta psi m). METHOD A low differentiation human nasopharyngeal carcinoma (NPC) cell line of CNE-2Z cells were used as in vitro model. After treatment with 2 mumol/L CPT for 24 h, the delta psi m was detected by the staining of rhodamine 123 (Rh123), while apoptosis was confirmed by sub-G1 cell content and the double staining of hoechst33258 and propidium iodide (PI). RESULT CPT induced delta psi m collapse and apoptosis. With 2 mumol/L CPT treatment for 24 h, delta psi mlow cell was increased to (19.0 +/- 3.0)%, while in the DMSO control, delta psi mlow was (7.0 +/- 1.4)% P < 0.05. CONCLUSION The disruption of the delta psi m may be one of the mechanisms of CPT-induced apoptosis in CNE-2Z cells.
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927
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Padmanabhan S, Zhou K, Chu CY, Lim RW, Lim LW. Overexpression, biophysical characterization, and crystallization of ribonuclease I from Escherichia coli, a broad-specificity enzyme in the RNase T2 family. Arch Biochem Biophys 2001; 390:42-50. [PMID: 11368513 DOI: 10.1006/abbi.2001.2359] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have constructed a strain that overproduces ribonuclease I of Escherichia coli and we have purified large quantities of the enzyme. Data from fluorescence, CD, and DSC measurements showed that it was a very stable protein. The conformation energy determined from urea and guanidine hydrochloride denaturation experiments was 11.5 kcal mol(-1) at pH 7.5. Thermal denaturation studies indicated that it had a T(m) of 64 degrees C at pH 4.0. RNase I belongs to the RNase T2/S-RNase group of endoribonucleases, but near the amino terminus it has an unusually long hydrophilic segment. Part of this was removed in the deletion construct, RNase I Delta(26-38). We have obtained crystals of both RNase I and of an enzyme-G2'p5'G complex in the P2(1) space group and oligonucleotide complexes with both wild type and mutant enzymes. The current study lays the groundwork for extensive investigation into the structure, function, and physical properties of this widely distributed group of ribonucleases.
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928
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Yan F, Zhou K, Wu D, Yang J, Gong J, Shen J. [Evaluation of dynamic enhanced fast multiplanar spoiling gradient recalled(FMPSPGR) in the diagnosis of small hepatocellular carcinoma]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2001; 9:139-41. [PMID: 11412386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE To analyze the features of small hepotocellular carcinoma (SHCC) by spin echo (SE) sequence and dynamic enhanced FMPSPGR, and to compare the sensitivity for detecting and the accuracy for characterization, further to discuss the value of FMPSPGR in the diagnosis of SHCC. METHODS SE T(1)WI, T(2)WI and FMPSPGR dynamic imaging of the liver were performed for 58 patients with SHCC. The sensitivity for detecting and accuracy for characterization were statistically compared. RESULTS Seventy-two lesions were found in 58 patients. In the detection of SHCC, the order of the sensitivity was dynamic enhanced FMPSPGR>SE T(2)WI>no-enhanced FMPSPGR>SE T(1)WI. Dynamic enhanced FMPSPGR was significantly higher than any of the others. There was significant difference between no-enhanced FMPSPGR and SE T(2)WI, but not significant difference between T(2)WI and no-enhanced FMPSPGR. In the characterization of SHCC, the accuracy of pre- and post-contrast FMPSPGR was significantly higher than that of SE (T(1)WI+T(2)WI) with remarkable statistical difference. CONCLUSIONS FMPSPGR dynamic imaging is superior to SE in the detection and characterization of SHCC. The sensitivity for detecting and the accuracy for characterization will be improved when both FMPSPGR and SE are used.
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929
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Liu Z, Wang Y, Zhou K, Han D, Yang X, Liu X. Authentication of Chinese crude drug, Gecko, by allele-specific diagnostic PCR. PLANTA MEDICA 2001; 67:385-387. [PMID: 11458468 DOI: 10.1055/s-2001-14321] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Based on the sequences of the mitochondrial 12S rRNA gene fragment of 17 samples from Gekkonidae, Salamandridae, Agamidae and Hynobiidae, respectively, a pair of allele-specific primers was designed for differentiating the Chinese medicinal material Gecko from its adulterants by PCR. The results of amplification with the primers indicate that amplicons from the templates of Gekko gecko were clearly revealed by agarose gel electrophoresis, whereas no evident amplicons were found from other species. The primers were employed to identify crude drug samples from different sources. Among a total of 9 samples, 3 were diagnosed as genuine Gecko. This result is consistent with morphological identification and DNA sequence analyses.
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930
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Ju X, Wang J, Zhang W, Song X, Zhou K, Gong S. [A study on the relations of soluble interleukin-2 receptor and CD+25 cell with acute graft-versus-host disease]. ZHONGHUA NEI KE ZA ZHI 2001; 40:222-5. [PMID: 11798579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE Acute graft-versus-host disease (aGVHD) is one of the major complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Prediction of human aGVHD may be of help in its diagnosis and therapy. METHODS 22 patients undergoing HSCT were included in this study. After transplantation, serum concentrations of interleukin-6, interleukin-8, tumor necrosis factor-alpha, interferon-gamma and sIL-2R were measured periodically by using enzyme-linked immunosorbent assay. Immune reconstitution of CD(+)(3), CD(+)(4), CD(+)(8), CD(+)(25) and CD(+)(69) cells were analyzed with flow cytometry. RESULTS All the patients achieved engraftment. 6 patients developed grade I GVHD and 4 patients developed grade III-IV GVHD. Patients with aGVHD demonstrated significantly higher sIL-2R levels than those without. The peak levels of grade III-IV GVHD were (420.3 +/- 59.8) U/L,and the peak levels of grade I GVHD were (221.5 +/- 38.8) U/L. The increase of sIL-2R level in serum preceded the clinical signs of aGVHD. The maximum levels of sIL-2R correlated significantly with the severity of aGVHD. The increase of CD(+)(25) cells was in accordance with that of sIL-2R. CONCLUSIONS Analysis of serum cytokines and immune reconstitution after HSCT may provide predictive value for aGVHD.
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931
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Xie Q, Liu K, Hu M, Wu X, Zhou K. [Influence of scatter factor/hepatocyte growth factor on the growth and transmission of hepatocarcinoma SMMC 7721 cells]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2001; 9:95-7. [PMID: 11350688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
OBJECTIVE To explore the influence of scatter factor/hepatocyte growth factor (SF/HGF) on the growth and transmission of hepatocarcinoma SMMC 7721 cells by SF/HGF cDNA transfection. METHODS Gene transfection was operated by lipofectin method. In vitro, SF/HGF and c-met expression was tested by ELISA and Western blot. Cell proliferation and motility were compared by growth curves and wound healing assays. In vivo, cells before and after transfection were implanted subcutaneously into nude mice respectively to observe tumor growth and metastasis. RESULTS After transfection, the expression of SF/HGF reached 694 pg/ml, compared with 0.26 pg/ml before transfection; however the expression of c-met protein did not change obviously. Growth curves showed that cells after transfection proliferated more rapidly than those before transfection and had an increased capability of motility together with enlarged morphological changes. In vivo experiment, tumors originated from SF/HGF(+) cells grew faster than those from SF/HGF(-) cells and had embolism formed inside and metastasis in the corresponding lung tissues, whereas no such findings in SF/HGF(-) cell originated tumors. CONCLUSIONS High expression of SF/HGF can stimulate tumor cell proliferation and metastasis in hepatocellular carcinoma
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932
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Spahn CM, Kieft JS, Grassucci RA, Penczek PA, Zhou K, Doudna JA, Frank J. Hepatitis C virus IRES RNA-induced changes in the conformation of the 40s ribosomal subunit. Science 2001; 291:1959-62. [PMID: 11239155 DOI: 10.1126/science.1058409] [Citation(s) in RCA: 416] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Initiation of protein synthesis in eukaryotes requires recruitment of the 40S ribosomal subunit to the messenger RNA (mRNA). In most cases, this depends on recognition of a modified nucleotide cap on the 5' end of the mRNA. However, an alternate pathway uses a structured RNA element in the 5' untranslated region of the messenger or viral RNA called an internal ribosomal entry site (IRES). Here, we present a cryo-electron microscopy map of the hepatitis C virus (HCV) IRES bound to the 40S ribosomal subunit at about 20 A resolution. IRES binding induces a pronounced conformational change in the 40S subunit and closes the mRNA binding cleft, suggesting a mechanism for IRES-mediated positioning of mRNA in the ribosomal decoding center.
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933
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Kieft JS, Zhou K, Jubin R, Doudna JA. Mechanism of ribosome recruitment by hepatitis C IRES RNA. RNA (NEW YORK, N.Y.) 2001; 7:194-206. [PMID: 11233977 PMCID: PMC1370078 DOI: 10.1017/s1355838201001790] [Citation(s) in RCA: 278] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Many viruses and certain cellular mRNAs initiate protein synthesis from a highly structured RNA sequence in the 5' untranslated region, called the internal ribosome entry site (IRES). In hepatitis C virus (HCV), the IRES RNA functionally replaces several large initiation factor proteins by directly recruiting the 43S particle. Using quantitative binding assays, modification interference of binding, and chemical and enzymatic footprinting experiments, we show that three independently folded tertiary structural domains in the IRES RNA make intimate contacts to two purified components of the 43S particle: the 40S ribosomal subunit and eukaryotic initiation factor 3 (eIF3). We measure the affinity and demonstrate the specificity of these interactions for the first time and show that the high affinity interaction of IRES RNA with the 40S subunit drives formation of the IRES RNA-40S-eIF3 ternary complex. Thus, the HCV IRES RNA recruits 43S particles in a mode distinct from both eukaryotic cap-dependent and prokaryotic ribosome recruitment strategies, and is architecturally and functionally unique from other large folded RNAs that have been characterized to date.
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934
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Zhang S, Wang W, Zhou K, Liu H. Sequence variations of the hypervariable region of hepatitis C virus and their clinical significance. Chin Med J (Engl) 2000; 113:1075-9. [PMID: 11776139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To understand the clinical significance of sequence variations in the hypervariable region (HVR) of hepatitis C virus during infection. METHODS Eight patients with acute hepatitis C and 20 patients with chronic hepatitis C were followed up for two years. Blood samples were taken at intervals of six months for analysis of HCV-HVR sequences by reverse transcription-polymerase chain reaction (RT-PCR) and direct sequencing methods. RESULTS HCV-HVR sequences of the 28 patients changed in various degrees. 92% of these nucleotide substitutions led to changes of corresponding aminoacid sequences. Only 8% of changed nucleotide were synonymous substitutions. Of 27 amino acids variation of amino acid ranged from 1 to 20 (mean 8, 30%). The most common nucleotide substitution (62%) occurred in the first position of codon, 31% in the second and the rest in the third. HVR variation rate was 0.89 x 10(-1) per genome site per year in acute hepatitis C, compared with 2.31 x 10(-1) per genome site per year in chronic hepatitis C (P < 0.05), but had no relation to HCV subtype. Variation of HVR in the flare up type (ALT > 150 mu/L) was much more than that in the quiescent type (ALT < 100 mu/L). CONCLUSION Our results suggested that sequence variation of HVR during HCV chronic infection seems to be an adaptive response to HCV to evade the host immune pressure and might play a major role in the establishment of persistent infection as well as in the flare-up of hepatitis.
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935
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Greenstein S, Barnard J, Zhou K, Fong M, Hendey B. Fas activation reduces neutrophil adhesion to endothelial cells. J Leukoc Biol 2000; 68:715-22. [PMID: 11073112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Polymorphonuclear neutrophils (PMN) express apoptotic markers and lose effector functions including adhesion, chemotaxis, and phagocytosis when cultured overnight. Although the loss of function correlates with apoptosis, it is not clear if functions are lost before an early marker of apoptosis, the display of phosphatidylserine (PS), targets PMN for removal by phagocytic cells. To address this question, freshly isolated PMN were treated with Fas-activating antibodies to induce apoptosis rapidly. Early markers of apoptosis and PMA-stimulated adhesion to endothelial cells were measured. After 1 h of Fas exposure, only 16% PMN had externalized PS. In contrast, Fas activation reduced PMA-stimulated adhesion between 68 and 27% depending on PMA concentration. The loss of adhesion was accompanied by a reduction in beta2 integrin expression and receptor clustering. These results indicate that the Fas-induced loss of adhesion may precede PS externalization and could limit participation in the inflammatory response before PS externalization targets PMN for removal.
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936
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Wang Y, Zhou K, Xu L, Dong TT, Tsim KW. Authentication of an animal crude drug, Zaocys, by diagnostic PCR. Biol Pharm Bull 2000; 23:585-8. [PMID: 10823669 DOI: 10.1248/bpb.23.585] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A pair of diagnostic primers for distinguishing the Chinese crude drug Zaocys (Zaocys dhumandes) from its substitutes was designed based on the sequence data of the original animal of the drug and substitutes. Total DNAs were extracted from genuine crude drug and 5 of its substitutes, as well as from 12 species of original animal of the snake crude drug. Diagnostic PCRs were performed using the primers with these total DNAs as a template, annealing at 60-65 degrees C. Positive amplifications were obtained from all DNA templates of Zaocys, whereas negative amplifications were obtained from that of others. The results indicate that Zaocys samples could be definitely distinguished from its substitutes by diagnostic PCR, and no incorrect discrimination was found under the same reaction conditions. The advantages of the method in the authentication of crude drugs are also discussed in the present paper.
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937
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Zhou T, Rao H, Cai K, Zhou K, Zhou C, Zhuo Y, Chen L. The role of topological properties in apparent motion: A further fMRI mapping study. Neuroimage 2000. [DOI: 10.1016/s1053-8119(00)91682-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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938
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Bian Y, Li P, Gao Z, Wang Y, Zhou K, Tsim KW, Dong T. [Application of RAPD in the taxonomy of the genus Fritillaria]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 2000; 23:13-6. [PMID: 12575110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To provide the molecular data for the right application of the Chinese medicine "Beimu". METHOD Using the technology of RAPD, we studied the relationship among 12 samples of Beimu. RESULT The total genomic DNA of all the samples are about 21 Kb in size. Among 20 primers used, the five primers can reatedly generate a certain specified amplified band type, 27 bands were recored from all amplified products and 25 polymorphic fragments were found in it. The size of amplified fragments is between 450 bp and 1904 bp. CONCLUSION The similarity within species is higher than those between species. The relationship of Fritillaria anhuiensis and F. puqiensis is the farest, while F. thunbergii and F. puqiensis is the closest.
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939
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Zhou K, Zhu M, Feng Y. [Effects of synthetic peptides on ovarian cancer cells]. ZHONGHUA FU CHAN KE ZA ZHI 1999; 34:726-8. [PMID: 11479960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE To observe the effect of follicle-stimulating hormone(FSH) synthetic peptides(FSH binding Fragment), FSH and synthetic peptides on the proliferation of human epithelial ovarian cancer cell. METHODS Human epithelial ovarian cancer cells lines SKOV3, OVCAR, AO and 3AO were incubated with FSH, FSH binding fragment, FSH and the binding fragment respectively. The cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) technique. RESULTS The rate of proliferation in the cancer cell was increased apparently as increasing in the concentration of FSH and the rate of proliferation average value 28.0%, and was decreased apparently as increasing in the concentration of the synthetic peptides and the rate of inhibition average value 8.3%. When the cell was expressed in FSH, the proliferation was decreased apparently as increasing in the concentration of the peptides and the rate of inhibition average valve 3.1%. CONCLUSIONS It is suggested that FSH binding fragment can inhibit the proliferation of ovarian cancer cell. The FSH binding fragment could be used as a binding part of anticancerous complex for ovarian cancer.
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940
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Kieft JS, Zhou K, Jubin R, Murray MG, Lau JY, Doudna JA. The hepatitis C virus internal ribosome entry site adopts an ion-dependent tertiary fold. J Mol Biol 1999; 292:513-29. [PMID: 10497018 DOI: 10.1006/jmbi.1999.3095] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) contains an internal ribosome entry site (IRES) located in the 5' untranslated region of the genomic RNA that drives cap-independent initiation of translation of the viral message. The approximate secondary structure and minimum functional length of the HCV IRES are known, and extensive mutagenesis has established that nearly all secondary structural domains are critical for activity. However, the presence of an IRES RNA tertiary fold and its functional relevance have not been established. Using chemical and enzymatic probes of the HCV IRES RNA in solution, we show that the IRES adopts a unique three-dimensional structure at physiological salt concentrations in the absence of additional cofactors or the translation apparatus. Folding of the IRES involves cooperative uptake of magnesium and is driven primarily by charge neutralization. This tertiary structure contains at least two independently folded regions which closely correspond to putative binding sites for the 40 S ribosomal subunit and initiation factor 3 (eIF3). Point mutations that inhibit IRES folding also inhibit its function, suggesting that the IRES tertiary structure is essential for translation initiation activity. Chemical and enzymatic probing data and small-angle X-ray scattering (SAXS) experiments in solution show that upon folding, the IRES forms an extended structure in which functionally important loops are exposed. These results suggest that the 40 S ribosomal subunit and eIF3 bind an HCV IRES that is prefolded to spatially organize recognition domains.
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941
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Zhou K, Yan F, Tu B. [Evaluation of the arterial phase of biphase enhanced SCT in the diagnosis of small HCC]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 1999; 7:135-7. [PMID: 10572676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
OBJECTIVE To evaluate the value of the arterial phase (AP) of biphase enhanced SCT in the diagnosis of small HCC and investigate the criteria, initial time, ending time and duration of AP. METHODS From May 1995 to March 1999, patients with small HCC proved by surgicopathology including 49 cases (N = 53) in the 1st group, 148 cases (N = 186) in the 2nd group and 52 cases (N = 52)n in the 3rd group were collected. Biphase dynamic enhanced SCT scans were performed in all patients of three groups and additional single-level dynamic scans only done in the 3rd group. The detectability, diagnostic accuracy of the lesions and enhancement of the lesion in AP were analyzed statistically. In addition, the initial time, ending time and duration of AP were measured. RESULTS The results of the 1st group showed the detectability of small HCC was 88.68% in AP and 90.57% in both phases, higher than those by US. Markedly enhanced lesion in AP accounted for 76% and 78% in the 2nd and 3rd groups respectively. The initial, ending and duration times of AP measured on single-level dynamic scans were 16.9 s, 39.6 s and 22.7 s in average respectively. CONCLUSION The biphase dynamic SCT especially its arterial phase appears to be very valuable in diagnosing small HCCs. In light of short duration of AP, understanding and strict control of AP is obviously imperative.
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942
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Zhou K, Wang J, Liu B. [Clinical study on effect of shenqi fuzheng injection combined with chemotherapy in treating gastric cancer]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1999; 19:11-3. [PMID: 11783251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To assess the clinical effect of Shenqi Fuzheng Injection (SQFZI) combined with chemotherapy in treating gastric cancer. METHODS One hundred and twenty patients were randomly divided into 3 groups, the combined therapy group (Group A), the chemotherapy group (Group B) and the SQFZI group (Group C) and the effect on remission and stabilization of patients were observed. RESULTS The remission rate and stabilizing rate of Group A were 16.1% and 87.1%, those of Group B were 13.5% and 64.9%, the difference between the two groups was significant, P < 0.05. The symptom and living quality improving rate of Group A were 75.8% and 43.5% respectively, those of Group C were 61.9% and 57.1% and of Group B were 35.1% and 29.7% respectively. SQFZI showed good protective effect on hemopoietic system, 4.8% patients in Group A with WBC count lower than 4 x 10(9)/L, while the percentage reached 21.6% in Group B, the difference between the two groups was significant, P < 0.05. Moreover, SQFZI could raise activity of NK cell, macrophage and T-lymphocyte subgroups, without any injury on heart, liver and kidney function or other adverse reaction. CONCLUSION SQFZI combined with chemotherapy has certain effect of remission and stabilization on gastric cancer, the clinical effect is significant to patients with Qi-Deficiency, and is reliable and safe.
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943
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Wang Y, Zhou K, Xu L, Xu G. [Sequencing of Cyt b gene fragments and PCR identification of "jinqian baihuashe" (Bungarus parvus) and its adulterants]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1998; 33:941-7. [PMID: 12016862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
DNAs extracted from both "Jinqian Baihuashe" (Bungarus parvus) and its adulterants and original animals of the crude snake drugs were used as templates for Cyt b gene fragment amplification. The sequence data of the fragments showed that the differences of the sequence between Bungarus parvus and its adulterants were far greater than that between intraspecific variations of Bungarus parvus. Therefore, the Cyt b gene fragment was a good molecular genetic marker for the authentication of Bungarus parvus. On the basis of the sequence data, a pair of specialized primers, BuL-1 and BuH-1 was designed for the PCR identification of Bungarus parvus. The effectiveness of the primers were examined at a series of anneal temperatures. The results showed that Bungarus parvus samples could be absolutely distinguished when the anneal temperatures were 60 degrees C-65 degrees C, whereas no incorrect or missing discrimination was found at these temperatures. The results also showed that the powder of Bungarus parvus which was mixed with powders of three other crude snake drugs may be detected by the PCR identification. This indicates that PCR identification may be a new method for examining the compositions of Chinese patent medicine.
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944
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Chung CY, Reddy TB, Zhou K, Firtel RA. A novel, putative MEK kinase controls developmental timing and spatial patterning in Dictyostelium and is regulated by ubiquitin-mediated protein degradation. Genes Dev 1998; 12:3564-78. [PMID: 9832508 PMCID: PMC317245 DOI: 10.1101/gad.12.22.3564] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/1998] [Accepted: 09/22/1998] [Indexed: 11/25/2022]
Abstract
We have identified a developmentally regulated, putative MEK kinase (MEKKalpha) that contains an F-box and WD40 repeats and plays a complex role in regulating cell-type differentiation and spatial patterning. Cells deficient in MEKKalpha develop precociously and exhibit abnormal cell-type patterning with an increase in one of the prestalk compartments (pstO), a concomitant reduction in the prespore domain, and a loss of the sharp compartment boundaries, resulting in overlapping prestalk and prespore domains. Overexpression of MEKKalpha or MEKKalpha lacking the WD40 repeats results in very delayed development and a severe loss of compartment boundaries. Prespore and prestalk cells are interspersed throughout the slug. Analysis of chimeric organisms suggests that MEKKalpha function is required for the proper induction and maintenance of prespore cell differentiation. We show that the WD40 repeats target MEKKalpha to the cortical region of the cell, whereas the F-box/WD40 repeats direct ubiquitin-mediated MEKKalpha degradation. We identify a UBC and a UBP (ubiquitin hydrolase) that interact with the F-box/WD40 repeats. Our findings indicate that cells lacking the ubiquitin hydrolase have phenotypes similar to those of MEKKalpha null (mekkalpha-) cells, further supporting a direct genetic and biochemical interaction between MEKKalpha, the UBC, and the UBP. We demonstrate that UBC and UBP differentially control MEKKalpha ubiquitination/deubiquitination and degradation through the F-box/WD40 repeats in a cell-type-specific and temporally regulated manner. Our results represent a novel mechanism that includes targeted protein degradation by which MAP kinase cascade components can be controlled. More importantly, our findings suggest a new paradigm of spatial and temporal control of the kinase activity controlling spatial patterning during multicellular development, which parallels the temporally regulated degradation of proteins required for cell-cycle progression.
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945
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Abstract
The self-cleaving ribozyme of the hepatitis delta virus (HDV) is the only catalytic RNA known to be required for the viability of a human pathogen. We obtained crystals of a 72-nucleotide, self-cleaved form of the genomic HDV ribozyme that diffract X-rays to 2.3 A resolution by engineering the RNA to bind a small, basic protein without affecting ribozyme activity. The co-crystal structure shows that the compact catalytic core comprises five helical segments connected as an intricate nested double pseudoknot. The 5'-hydroxyl leaving group resulting from the self-scission reaction is buried deep within an active-site cleft produced by juxtaposition of the helices and five strand-crossovers, and is surrounded by biochemically important backbone and base functional groups in a manner reminiscent of protein enzymes.
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946
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Lin S, Liu J, Xin P, Fang Y, Zhang Z, Zhou K. [Effect of hyperbaric oxygen on cerebral microcirculation and tissue cells in animals with cerebral ischemic injury]. HANG TIAN YI XUE YU YI XUE GONG CHENG = SPACE MEDICINE & MEDICAL ENGINEERING 1998; 11:338-42. [PMID: 11543255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Changes of cerebral microcirculation and tissue cells after Hyperbaric Oxygen (HBO) exposure were observed in 136 gerbils with cerebral ischemia by observation of meningeal microcirculation pathological study in cerebral tissues and determination of Na, K-ATPase. It is indicated that HBO may be helpful in improving microcirculatory dynamics and other microcirculatory functions, and enhancing cerebral tissue cell activity and cell function, as well as increasing oxygen content. It is suggested that HBO (250 approximately 300kPa) may play a role in protecting vessel endothelial cells and nerve cells.
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Zhou K, Wang Y, Gorski JL, Nomura N, Collard J, Bokoch GM. Guanine nucleotide exchange factors regulate specificity of downstream signaling from Rac and Cdc42. J Biol Chem 1998; 273:16782-6. [PMID: 9642235 DOI: 10.1074/jbc.273.27.16782] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Rac and Cdc42 GTPases regulate diverse cellular behaviors involving the actin cytoskeleton, gene transcription, and the activity of multiple protein and lipid kinases. All of these pathways can potentially become activated when GTP-Rac or GTP-Cdc42 is formed in response to external cell signals, yet it is evident that each activity must also be able to be controlled individually. The mechanisms by which such specificity of GTPase signaling in response to upstream stimuli is achieved remains unclear. We investigated the action of several well characterized guanine nucleotide exchange factors (GEFRho) to activate Rac- and/or Cdc42-dependent kinase pathways. Coexpression studies in COS-7 cells revealed that the ability of individual guanine nucleotide exchange factors (GEFs) to activate the p21-activated kinase PAK1 could be dissociated from activation of c-Jun amino-terminal kinase, even though activation of both pathways requires the action of the GEFs on Rac and/or Cdc42. In contrast, expression of constitutively active forms of Rac or Cdc42 effectively stimulated both downstream kinases. We conclude that GEFs can be important determinants of downstream signaling specificity for members of the Rho GTPase family.
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Abstract
Crystallization of RNA molecules other than simple oligonucleotide duplexes remains a challenging step in structure determination by X-ray crystallography. Subjecting biochemically, covalently and conformationally homogeneous target molecules to an exhaustive array of crystallization conditions is often insufficient to yield crystals large enough for X-ray data collection. Even when large RNA crystals are obtained, they often do not diffract X-rays to resolutions that would lead to biochemically informative structures. We reasoned that a well-folded RNA molecule would typically present a largely undifferentiated molecular surface dominated by the phosphate backbone. During crystal nucleation and growth, this might result in neighboring molecules packing subtly out of register, leading to premature crystal growth cessation and disorder. To overcome this problem, we have developed a crystallization module consisting of a normally intramolecular RNA-RNA interaction that is recruited to make an intermolecular crystal contact. The target RNA molecule is engineered to contain this module at sites that do not affect biochemical activity. The presence of the crystallization module appears to drive crystal growth, in the course of which other, non-designed contacts are made. We have employed the GAAA tetraloop/tetraloop receptor interaction successfully to crystallize numerous group II intron domain 5-domain 6, and hepatitis delta virus (HDV) ribozyme RNA constructs. The use of the module allows facile growth of large crystals, making it practical to screen a large number of crystal forms for favorable diffraction properties. The method has led to group II intron domain crystals that diffract X-radiation to 3.5 A resolution.
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949
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Cheng M, Liang T, Zhou K, Ling G. [Rapid determination of creatinine in urine by capillary electrophoresis in a multiple injection mode]. Se Pu 1998; 16:149-51. [PMID: 11326983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
The level of urinary creatinine in clinic diagnosis is one of the useful index of renal function, and is often used as a reference of some biochemical substance determined in random urine. In this paper, a rapid multiple-injection capillary electrophoresis(CE) method for the determination of urinary creatinine is reported. A 36 cm x 50 microns coated capillary, a phosphoric acid buffer(0.1 mol/L, pH 2.5)and UV-detector at 200 nm wavelength were used in this method. In comparing with single injection for five samples, the analysis time of five successive injections can save 20 min. By use of pyridine as internal standard, the correlation between the concentrations of creatinine and the corresponding peak height ratios of creatinine and pyridine is good(r = 0.9996), and the assay precision is acceptable. We also compared the CE method with the bio-analyser(Jeffe' kinetic), and the results showed a satisfactory correlation (r = 0.9773, n = 12) and a shorter analysis time.
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950
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Zheng J, Jia Y, Zhou K. [A study on enzymatic activities of bronchoalveolar lavage fluid in patients with interstitial lung diseases]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1998; 21:91-3. [PMID: 11263392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To evaluate the relationship between enzymatic activities in bronchoalveolar lavage fluid(BALF) and interstitial lung diseases(ILDs). METHOD Cellular components and levels of superoxide dismutase (SOD), glutathione peroxidase(GSH-PX), angiotensin converting enzyme(ACE) and lactate dehydrogenase(LDH) in BALF in 30 cases of ILDs: including 18 patients with idiopathic pulmonary fibrosis (IPF) and 12 patients with sarcoidosis (Sarc) and 9 healthy controls were determined. RESULT (1) The levels of BALF-SOD, GSH-PX were significantly decreased(P < 0.01), and BALF-ACE, LDH were markedly increased (P < 0.05) in patients with IPF, and BALF-ACE were also increased in patients with Sarc(P < 0.05); (2) There were good correlation between ACE and percentage of lymphocyte (r1 = 0.6574, P < 0.05), and ratio of CD4+/CD8+ (r2 = 0.9544, P < 0.001) in BALF of Sarc group. CONCLUSION Determining enzymatic activities could be helpful to study pathogenesis and diagnosis of ILDs, BALF-ACE may be as a good marker of disease activity of Sarcoidosis.
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