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Chen RJ, Zhang Y, Wang D, Dai H. Noncovalent sidewall functionalization of single-walled carbon nanotubes for protein immobilization. J Am Chem Soc 2001; 123:3838-9. [PMID: 11457124 DOI: 10.1021/ja010172b] [Citation(s) in RCA: 1347] [Impact Index Per Article: 58.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zhao S, Dai H, Shao D. [Predictive value of combined application of umbilical artery color Doppler velocimetry, nonstress testing and ultrasonography in monitoring umbilical cord entanglement]. ZHONGHUA YI XUE ZA ZHI 2001; 81:468-71. [PMID: 11798920] [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 explore the predictive value of combined application of umbilical artery color Doppler flow monitoring (CDFI), nonstress testing (NST) and ultrasonography in monitoring umbilical cord entanglement. METHODS 1 860 cases of pregnant women between gestational ages of 37 approximately 42 weeks were studied 1 approximately 2 weeks before delivery by CDFI, nonstress testing (NST) and ultrasonography to monitor umbilical cord entanglement. RESULTS The prevalence rate of umbilical cord entanglement was 23.23% (432/1 860). Positive predictive value and negative predictive value were 95.4 % (412/432) and 98.6% (1 408/1 428) respectively. The rate of accuracy was 97.8% (1 820/1 860). The rate of fetal distress among the fetuses with umbilical cord round the body or four limbs was 85.29% (23/34) and the incidence of cesarean section in this group was 88.28% (30/34). The rate of fetal distress among the fetuses with umbilical cord round the neck was 13.06% (52/398) and the incidence of cesarean section in this group was 44.94% (178/398). The rates of fetal distress and cesarean section were significantly higher in the group with umbilical cord around the body or four limbs than in the group with umbilical cord around the neck (chi(2) = 107.27 and 23.76 respectively, P < 0.001). The systolic/diastolic (S/D) ratio was basically in normal ranges in the group with the umbilical cord round the neck. In cardiotopography (CTG), umbilical cord entanglement mainly showed variable deceleration (VD), early deceleration (ED), nonreaction on NST, and late deceleration (LD) on oxytocin challenge test (OCT). Prolonged fetal heart rate deceleration (PD) could be seen in the group with umbilical cord around the body or four limbs. CONCLUSION The combined application of umbilical artery color Doppler velocimetry, nonstress testing and ultrasonography have an important auxiliary value in monitoring umbilical cord entanglement. It remarkably increases the positive predictive rate as a valuable reference for the choice of delivery form.
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Hughes TR, Mao M, Jones AR, Burchard J, Marton MJ, Shannon KW, Lefkowitz SM, Ziman M, Schelter JM, Meyer MR, Kobayashi S, Davis C, Dai H, He YD, Stephaniants SB, Cavet G, Walker WL, West A, Coffey E, Shoemaker DD, Stoughton R, Blanchard AP, Friend SH, Linsley PS. Expression profiling using microarrays fabricated by an ink-jet oligonucleotide synthesizer. Nat Biotechnol 2001; 19:342-7. [PMID: 11283592 DOI: 10.1038/86730] [Citation(s) in RCA: 829] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We describe a flexible system for gene expression profiling using arrays of tens of thousands of oligonucleotides synthesized in situ by an ink-jet printing method employing standard phosphoramidite chemistry. We have characterized the dependence of hybridization specificity and sensitivity on parameters including oligonucleotide length, hybridization stringency, sequence identity, sample abundance, and sample preparation method. We find that 60-mer oligonucleotides reliably detect transcript ratios at one copy per cell in complex biological samples, and that ink-jet arrays are compatible with several different sample amplification and labeling techniques. Furthermore, results using only a single carefully selected oligonucleotide per gene correlate closely with those obtained using complementary DNA (cDNA) arrays. Most of the genes for which measurements differ are members of gene families that can only be distinguished by oligonucleotides. Because different oligonucleotide sequences can be specified for each array, we anticipate that ink-jet oligonucleotide array technology will be useful in a wide variety of DNA microarray applications.
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Christiani DC, Wang XR, Pan LD, Zhang HX, Sun BX, Dai H, Eisen EA, Wegman DH, Olenchock SA. Longitudinal changes in pulmonary function and respiratory symptoms in cotton textile workers. A 15-yr follow-up study. Am J Respir Crit Care Med 2001; 163:847-53. [PMID: 11282755 DOI: 10.1164/ajrccm.163.4.2006063] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
To evaluate the chronic effects of exposure to cotton dust, a 15-yr follow-up study in cotton textile workers was performed in Shanghai, China from 1981 to 1996. Testing occurred four times during the 15-yr period. The achieved follow-up rates were 76-88% of the original 447 cotton textile workers, and 70-85% of the original 472 silk textile workers (as a control group). Identical questionnaires, equipment, and methods were used throughout the study. The prevalence of byssinosis increased over time in cotton workers, with 15.3% at the last survey versus 7.6% at the baseline, whereas no byssinosis was found in silk workers. More workers in the cotton group consistently reported symptoms than in the silk group, although symptom reporting varied considerably from survey to survey. Cotton workers had small, but significantly greater, adjusted annual declines in FEV(1) and FVC than did the silk workers. Years worked in cotton mills, high level of exposure to endotoxin, and across-shift drops in FEV(1) were found to be significant determinants for longitudinal change in FEV(1), after controlling for appropriate confounders. Furthermore, there were statistically significant associations between excessive loss of FEV(1) and byssinosis, chest tightness at work, and chronic bronchitis in cotton workers. Workers who consistently (three or four of the surveys) reported byssinosis or chest tightness at work had a significantly greater 15-yr loss of FEV(1). We conclude that long-term exposure to cotton dust is associated with chronic or permanent obstructive impairments. Consistent reporting of respiratory symptoms, including byssinosis and chest tightness at work, is of value to predict the magnitude and severity of chronic impairments in textile workers.
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Shoemaker DD, Schadt EE, Armour CD, He YD, Garrett-Engele P, McDonagh PD, Loerch PM, Leonardson A, Lum PY, Cavet G, Wu LF, Altschuler SJ, Edwards S, King J, Tsang JS, Schimmack G, Schelter JM, Koch J, Ziman M, Marton MJ, Li B, Cundiff P, Ward T, Castle J, Krolewski M, Meyer MR, Mao M, Burchard J, Kidd MJ, Dai H, Phillips JW, Linsley PS, Stoughton R, Scherer S, Boguski MS. Experimental annotation of the human genome using microarray technology. Nature 2001; 409:922-7. [PMID: 11237012 DOI: 10.1038/35057141] [Citation(s) in RCA: 332] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The most important product of the sequencing of a genome is a complete, accurate catalogue of genes and their products, primarily messenger RNA transcripts and their cognate proteins. Such a catalogue cannot be constructed by computational annotation alone; it requires experimental validation on a genome scale. Using 'exon' and 'tiling' arrays fabricated by ink-jet oligonucleotide synthesis, we devised an experimental approach to validate and refine computational gene predictions and define full-length transcripts on the basis of co-regulated expression of their exons. These methods can provide more accurate gene numbers and allow the detection of mRNA splice variants and identification of the tissue- and disease-specific conditions under which genes are expressed. We apply our technique to chromosome 22q under 69 experimental condition pairs, and to the entire human genome under two experimental conditions. We discuss implications for more comprehensive, consistent and reliable genome annotation, more efficient, full-length complementary DNA cloning strategies and application to complex diseases.
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Fukushima H, Hao Q, Wu K, Hu X, Chen J, Guo Z, Dai H, Qin C, Lu S, Gomyoda M. Yersinia enterocolitica O9 as a possible barrier against Y. pestis in natural plague foci in Ningxia, China. Curr Microbiol 2001; 42:1-7. [PMID: 11116388 DOI: 10.1007/s002840010168] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A survey of Yersinia spp, as related to plague control, was made in Haiyuan of Ganning loess plateau plague focus, Yanchi of Inner Mongolia plateau plague focus, and Yinchuan city, as a control area, in Ningxia, China. In Haiyuan, where the main plague reservoir was Mongolian ground squirrel (Citellus alaschanicus) living in the prairie, Y. enterocolitica O9 was frequently isolated from pigs, dogs, rodents living in and around houses, but only rarely from hare and Mongolian ground squirrel. In Yanchi, where the main plague reservoir was Mongolian gerbil (Meriones unguiculatus) living in the prairie and Y. pestis, which was isolated from rodents up to 1991, Y. enterocolitica O9 was sometimes isolated from pigs and rodents. In all areas, some strains of Y. enterocolitica O3 and Y. pseudotuberculosis serotypes 3 and 4b were also isolated from pigs, dogs, and from rodents. We propose that an epidemiological link exists between the prevalence of Y. pestis and Y. enterocolitica O9 in domestic and rodents living in these areas in China. The residential area in Haiyuan may be protected against Y. pestis by the domestic animals and rodents which acquired cross-protection against Y. pestis by infection with Y. enterocolitica O9, but this is not the case in the Yanchi district.
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Abstract
Modulation doping of a semiconducting single-walled carbon nanotube along its length leads to an intramolecular wire electronic device. The nanotube is doped n-type for half of its length and p-type for the other half. Electrostatic gating can tune the system into p-n junctions, causing it to exhibit rectifying characteristics or negative differential conductance. The system can also be tuned into n-type, exhibiting single-electron charging and negative differential conductance at low temperatures. The low-temperature behavior is manifested by a quantum dot formed by chemical inhomogeneity along the tube.
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Dai H, Hogan C, Gopalakrishnan B, Torres-Vazquez J, Nguyen M, Park S, Raftery LA, Warrior R, Arora K. The zinc finger protein schnurri acts as a Smad partner in mediating the transcriptional response to decapentaplegic. Dev Biol 2000; 227:373-87. [PMID: 11071761 DOI: 10.1006/dbio.2000.9901] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In Drosophila, a BMP-related ligand Decapentaplegic (Dpp) is essential for cell fate specification during embryogenesis and in imaginal disc development. Dpp signaling culminates in the phosphorylation and nuclear translocation of Mothers against dpp (Mad), a receptor-specific Smad that can bind DNA and regulate the transcription of Dpp-responsive genes. Genetic analysis has implicated Schnurri (Shn), a zinc finger protein that shares homology with mammalian transcription factors, in the Dpp signal transduction pathway. However, a direct role for Shn in regulating the transcriptional response to Dpp has not been demonstrated. In this study we show that Shn acts as a DNA-binding Mad cofactor in the nuclear response to Dpp. Shn can bind DNA in a sequence-specific manner and recognizes sites within a well-characterized Dpp-responsive promoter element, the B enhancer of the Ultrabithorax (Ubx) gene. The Shn-binding sites are relevant for in vivo expression, since mutations in these sites affect the ability of the enhancer to respond to Dpp. Furthermore we find that Shn and Mad can interact directly through discrete domains. To examine the relative contribution of the two proteins in the regulation of endogenous Dpp target genes we developed a cell culture assay and show that Shn and Mad act synergistically to induce transcription. Our results suggest that cooperative interactions between these two transcription factors could play an important role in the regulation of Dpp target genes. This is the first evidence that Dpp/BMP signaling in flies requires the direct interaction of Mad with a partner transcription factor.
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Ma S, Dai H, Chen X, Feng J. [The effect of HCPT combined with radiation on cell proliferation of human lung adenocarcinoma cell line (D₆) in vitro]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2000; 3:344-7. [PMID: 20979718 DOI: 10.3779/j.issn.1009-3419.2000.05.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND To study the adjuvant effects of HCPT and radiation on cell proliferation of human lung adenocarcinoma cell line (D₆) in vitro. METHODS Suppression rate of cell growth,apoptosis and cell cycle of human pulmonary adenocarcinoma cell line were detected by MTT assay,DNA agrose electrophoresis and flow-cytometry respectively. RESULTS The suppression effects of HCPT on cell proliferation were dose and time dependent.The cells were significantly blocked at S stage by HCPT.Apoptosis peak appeared at 24 and 48 hours after treatment with high concentration (50μg/ml) and low concentration of HCPT (1μg/ml) respectively.DNA "Ladder" started to appear at 48 hours by radiation alone,but DNA "Ladder" and apoptosis peak both appeared at 24-72 hours and 0-72 hours after treatment with HCPT alone and HCPT combined with radiation respectively. CONCLUSIONS HCPT combined with radiation may show the synergistic killing effect on human lung adenocarcinoma cell line (D₆) in vitro.
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Dai H, Bai C. [The meridian flowing and ancient Chinese philosophy]. ZHONGHUA YI SHI ZA ZHI (BEIJING, CHINA : 1980) 2000; 30:219-21. [PMID: 11871432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
The theories of Yin - Yang and Five - Evolutive phase were extensively applied after pre - Qin and both Han dynasties. In the Song - Ming dynasties, the background of New Confucianism, the achievements of art of Yi(Changes) advocated by the "School of Configuration - Arithmatic" were applied, in which the method of "Adopting of Jia" was almost entirely derived from the above school, mixing the theories of heavenly stems - earthly branches, Five - evolutive phases and Yin - Yang as a whole. An ancient system of Chronological treatment was thus established creatively by integrating clinical experience together. The system is a tight system of grafting medicine and philosophy formed on the basis of successfully utilizing the philosophical framework, thinking proposed by ancient physicians with keen observation and deep ponderation. The system is, by then, an advanced one, which is also an inevitable one.
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Wu J, Zhou Z, Ye S, Dai H, Ma L, Xu X, Li X. [Detection of soluble endothelial protein C receptor (sEPCR) in patients with CHD, DM and SLE]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2000; 21:472-4. [PMID: 11877022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To evaluate the clinical significance of plasma soluble endothelial protein C receptor (sEPCR) level in patients with coronary heart disease (CHD), diabetes mellitus (DM) and systemic lupus erythematosus (SLE). METHODS ELISA of antibody-sandwiched principle was used to detect sEPCR in 34 patients with CHD, 42 with DM-II, 63 with SLE and 20 normal controls (NC). RESULTS The plasma level of sEPCR in patients with DM was higher than that in NC group (P < 0.05). The sEPCR level in SLE patients with thrombosis and non-thrombosis are higher than that in NC group (P < 0.005 and P < 0.001, respectively). There is no significant difference between the two groups of SLE (P > 0.05), and between the CHD and NC groups. CONCLUSION sEPCR level increased in DM and SLE, it seems related to the process of inflammatory reaction and damage of endothelial cell.
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Hughes TR, Marton MJ, Jones AR, Roberts CJ, Stoughton R, Armour CD, Bennett HA, Coffey E, Dai H, He YD, Kidd MJ, King AM, Meyer MR, Slade D, Lum PY, Stepaniants SB, Shoemaker DD, Gachotte D, Chakraburtty K, Simon J, Bard M, Friend SH. Functional discovery via a compendium of expression profiles. Cell 2000; 102:109-26. [PMID: 10929718 DOI: 10.1016/s0092-8674(00)00015-5] [Citation(s) in RCA: 1631] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Ascertaining the impact of uncharacterized perturbations on the cell is a fundamental problem in biology. Here, we describe how a single assay can be used to monitor hundreds of different cellular functions simultaneously. We constructed a reference database or "compendium" of expression profiles corresponding to 300 diverse mutations and chemical treatments in S. cerevisiae, and we show that the cellular pathways affected can be determined by pattern matching, even among very subtle profiles. The utility of this approach is validated by examining profiles caused by deletions of uncharacterized genes: we identify and experimentally confirm that eight uncharacterized open reading frames encode proteins required for sterol metabolism, cell wall function, mitochondrial respiration, or protein synthesis. We also show that the compendium can be used to characterize pharmacological perturbations by identifying a novel target of the commonly used drug dyclonine.
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138
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Wang W, Wu S, Cheng X, Dai H, Ross K, Du X, Yin W. Prevalence of Alzheimer's disease and other dementing disorders in an urban community of Beijing, China. Neuroepidemiology 2000; 19:194-200. [PMID: 10859498 DOI: 10.1159/000026255] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A door-to-door two-phase study was used to investigate the prevalence of senile dementia in an urban community of Beijing. In the study population, 5,003 individuals aged 60 years and older (>/=65 years, n = 3,728) were screened at home with the Chinese version of the MMSE. Persons who screened positive for dementia, using different cutoff scores based on degree of literacy, were further evaluated using the criteria of DSM-III-R and ICD-10. Among subjects who screened positive in phase I, 134 were diagnosed as having dementia in phase II. The prevalence ratios of dementia were 2.68% in the population aged 60 years and older, and 3.49% in the population aged 65 years and older. The prevalence rates among those aged 65 years and older were 1.85% for Alzheimer's disease, 1.37% for vascular dementia and 0.27% for other dementia (including mixed dementia). The prevalence of all dementia and AD increased steeply with advancing age and was consistently higher in women, but it was not obviously higher for VaD in women. Alzheimer's disease was the commonest type of dementia. Our prevalence figures for dementia and AD are similar to those previously reported for China.
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Hughes TR, Roberts CJ, Dai H, Jones AR, Meyer MR, Slade D, Burchard J, Dow S, Ward TR, Kidd MJ, Friend SH, Marton MJ. Widespread aneuploidy revealed by DNA microarray expression profiling. Nat Genet 2000; 25:333-7. [PMID: 10888885 DOI: 10.1038/77116] [Citation(s) in RCA: 348] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Expression profiling using DNA microarrays holds great promise for a variety of research applications, including the systematic characterization of genes discovered by sequencing projects. To demonstrate the general usefulness of this approach, we recently obtained expression profiles for nearly 300 Saccharomyces cerevisiae deletion mutants. Approximately 8% of the mutants profiled exhibited chromosome-wide expression biases, leading to spurious correlations among profiles. Competitive hybridization of genomic DNA from the mutant strains and their isogenic parental wild-type strains showed they were aneuploid for whole chromosomes or chromosomal segments. Expression profile data published by several other laboratories also suggest the use of aneuploid strains. In five separate cases, the extra chromosome harboured a close homologue of the deleted gene; in two cases, a clear growth advantage for cells acquiring the extra chromosome was demonstrated. Our results have implications for interpreting whole-genome expression data, particularly from cells known to suffer genomic instability, such as malignant or immortalized cells.
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Zhou C, Kong J, Dai H. Intrinsic electrical properties of individual single-walled carbon nanotubes with small band gaps. PHYSICAL REVIEW LETTERS 2000; 84:5604-5607. [PMID: 10991005 DOI: 10.1103/physrevlett.84.5604] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/1999] [Indexed: 05/23/2023]
Abstract
Individual single-walled carbon nanotubes (SWNT) exhibiting small band gaps on the order of 10 meV are observed for the first time in electron transport measurements. Transport through the valence or conduction band of a small-gap semiconducting SWNT (SGS-SWNT) can be tuned by a nearby gate voltage. Intrinsic electrical properties of the Ohmically contacted SGS-SWNT are elucidated. An SGS-SWNT exhibits metal- or semiconductorlike characteristics depending on the Fermi level position in the band structure.
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141
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Liu L, Jayanthi CS, Tang M, Wu SY, Tombler TW, Zhou C, Alexseyev L, Kong J, Dai H. Controllable reversibility of an sp(2) to sp(3) transition of a single wall nanotube under the manipulation of an AFM tip: A nanoscale electromechanical switch? PHYSICAL REVIEW LETTERS 2000; 84:4950-4953. [PMID: 10990839 DOI: 10.1103/physrevlett.84.4950] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/1999] [Indexed: 05/23/2023]
Abstract
A simulation of the deflection of a single wall nanotube under the manipulation of an atomic force microscope tip revealed the key feature characterizing the deformation at relatively small bending angles to be a reversible transition from sp(2) to sp(3) bonding configurations in the bending region, leading to a 2 orders of magnitude reduction in conductance consistent with our most recent experimental observation. A local analysis elucidating the underlying physics of the findings is also discussed.
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Dai H, Mao Q, Yang H, Huang S, Chang Z. Probing the roles of the only universally conserved leucine residue (Leu122) in the oligomerization and chaperone-like activity of Mycobacterium tuberculosis small heat shock protein Hsp16.3. JOURNAL OF PROTEIN CHEMISTRY 2000; 19:319-26. [PMID: 11043937 DOI: 10.1023/a:1007003631120] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To understand the role of the only universally conserved hydrophobic residue among all the members of the sHsp family, this extremely well conserved Leu122 residue in Hsp16.3 was replaced by valine, alanine, asparigine, or aspartate residues. Only very small amounts of the L122D and L122N mutant Hsp16.3 proteins were expressed in the transformed E. coli; however, both the L122V and L122A were readily expressed. The L122V and L122A mutant proteins had similar oligomeric structures to the wild-type protein at room temperature. Examination of the L122A mutant protein by native pore gradient PAGE and CD spectroscopy, however, revealed a smaller oligomeric size and different secondary structure at 37 degrees C. Both L122V and L122A mutant proteins exhibited significantly lowered chaperone activities. Observations reported here suggest a very important role of this only universally conserved Leu residue in both the formation of specific oligomeric structures and the molecular chaperone activities of Hsp16.3.
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Huang L, Ruan Q, Dai H, Xu L, Deng H, Xia J. [Application of microdissection, PCR, and microcloning technique on human chromosomal study]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:115-9. [PMID: 10681819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Xu X, Dai H, Xia H, Zhu H, Wu J, Cui W. [Expression of telomerase activity in human lung cancer.]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2000; 3:91-93. [PMID: 20939961 DOI: 10.3779/j.issn.1009-3419.2000.02.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
BACKGROUND To investigate the expression of telomerase activity in lung cancer tissue and the correlation with the oncogenesis , progression and metastasis of lung cancer. METHODS Telomerase activity in specimens obtained by fiberbrochoscopy from 29 patients with suspected lung cancer was detected by polymerase chain reaction-ELISA. RESULTS The telomerase activity was positive in 18 cases of primary lung cancer and the positive rate was 81. 81 %(18/ 22) . Two of other seven specimens were positive for telomerase activity. Twelve lung cancer cases with lymph node metastasis showed positive expression , whereas only 6 of 10 cases without lymph node metastasis showed positive expression. CONCLUSIONS Telomerase activity may be useful both as a diagnostic marker to detect the existence of lung cancer and as a potential of high risk for lymph node metastasis.
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Hou WC, Wang YT, Lin YH, Hsiao LJ, Chen TE, Wang CW, Dai H. A complex containing both trypsin inhibitor and dehydroascorbate reductase activities isolated from mitochondria of etiolated mung bean (Vigna radiata L. (Wilczek) cv. Tainan no. 5) seedlings. JOURNAL OF EXPERIMENTAL BOTANY 2000; 51:713-719. [PMID: 10938863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A complex containing trypsin inhibitor (TI) activity was extracted with 0.1 M TRIS buffer (pH 7.9) from trypsin-treated mitochondria of etiolated mung bean seedlings, and further purified with a Superdex 200 FPLC column. This partially purified complex with an M(r) about 820 kDa exhibited additional dehydroascorbate (DHA) reductase activity with specific activities of 0.21, 1.53 and 1.54 mumol ascorbate formed min-1 mg-1 protein at pH 6.0, 6.5 and 7.0, respectively, when glutathione was added. Much lower DHA reductase activity (0.013 and 0.026 mumol ascorbate formed min-1 mg-1 protein at pH 6.5 and 7.0, respectively) was found when glutathione was omitted. The isolated complex gave positive results when it was tested by TI activity staining after SDS-PAGE, and could be recognized by a polyclonal antibody which was raised against 38 kDa sweet potato Kunitz-type TI, one of the root storage proteins of sweet potato. The possible physiological functions of this complex with both TI and DHA reductase activities were discussed.
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Tang B, Liu C, Shen L, Dai H, Pan Q, Jing L, Ouyang S, Xia J. Frequency of SCA1, SCA2, SCA3/MJD, SCA6, SCA7, and DRPLA CAG trinucleotide repeat expansion in patients with hereditary spinocerebellar ataxia from Chinese kindreds. ARCHIVES OF NEUROLOGY 2000; 57:540-4. [PMID: 10768629 DOI: 10.1001/archneur.57.4.540] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To assess the frequency of SCA1 (spinocerebellar ataxia type 1), SCA2, SCA3/MJD (spinocerebellar ataxia type 3/Machado-Joseph disease), SCA6, SCA7, and DRPLA (dentatorubropallidoluysian atrophy) CAG trinucleotide repeat expansions [(CAG)n] among persons diagnosed with hereditary SCA from Chinese families. PATIENTS AND METHODS Spinocerebellar ataxia type 1, SCA2, SCA3/MJD, SCA6, SCA7, and DRPLA (CAG)n mutation were detected with the polymerase chain reaction, highly denaturing polyacrylamide gel electrophoresis, and silver staining technique in 167 patients with autosomal dominant SCA from 85 Chinese families and 37 patients with sporadic SCA. RESULTS Spinocerebellar ataxia type 1 (CAG)n mutation in 7 patients from 4 kindreds (4.70%) was expanded to 53 to 62 repeats. Spinocerebellar ataxia type 2 (CAG)n mutation in 12 patients from 5 kindreds (5.88%) was expanded to 42 to 47 repeats. Spinocerebellar ataxia type 3/Machado-Joseph disease (CAG)n mutation in 83 patients from 41 kindreds (48.23%) was expanded to 68 to 83 repeats. Sixty-five patients from 35 kindreds (41.19%) and 37 patients with sporadic SCA did not test positive for SCA1, SCA2, SCA3/MJD, SCA6, SCA7, or DRPLA. There was a predictable inverse relationship between the number of CAG repeats and the age at onset for SCA3/MJD and SCA2. Clinically, dementia and hyporeflexia were more frequent in patients with SCA2, while spasticity, hyperreflexia, and Babinski signs were more frequent in patients with SCA3/ MJD, and those might be helpful in clinical work to primarily distinguish patients with SCA3/MJD and SCA2 from others with different types of SCA. CONCLUSIONS The frequency of SCA3/MJD is substantially higher than that of SCA1 and SCA2 in patients with autosomal dominant SCA from Chinese kindreds, who are non-Portuguese. Clinical expressions of the various types of SCAs overlap one another; therefore, for clinical study it is important to make a gene diagnosis and genetic classification for patients with SCA.
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Yu P, Zhang L, Dai H, Cha G, Sun Y, Shu M. [Research in the relationship between Chlamydia and ureaplasma and infertility]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:67-9. [PMID: 10681801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Samples taken from cervix and male urethra of 768 infertilitas patients were studied, and samples taken from 226 normal fertile males and females served as control. The fluorescent monoclonal antibody technique and cell culture method were used for Chlamydia trachomatis (Ct) and microbiological culture method was used for Ureaplasma urealyticum (Uu) detection. The positive rates of Ct and Uu infections were 28.64% (220/768) and 36.59% (281/768) in infertilitas group, 5.2% (14/266) and 14.28% (38/266) in control group respectively. There was significant difference between the 2 groups (P < 0.01). The results suggest that infection with Ct or Uu is one of the factors causing infertility.
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148
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Dai H, Chen T, Wang Z, Shi Z, Zhao B. [Vitrectomy for pseudophakic retinal detachment]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2000; 36:104-6. [PMID: 11853594] [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 the method of vitrectomy for treatment of pseudophakic retinal detachment. METHODS 32 pseudophakic retinal detachment eyes were treated with vitrectomy, primary vitrectomy in 11 eyes (34.4%), vitrectomy after conventional buckling failure in 21 eyes (65.6%), combined with silicone oil 10 eyes (31.3%), removal of intraocular lens 12 eyes (37.5%). All eyes had passed the 6 months to 5 years of follow-up examination. RESULTS Intra-operative new retinal breaks were identified in 7 eyes (21.9%). The retinal total reattachment was in 25 eyes (78.1%); part reattachment was in 4 eyes (12.5%), and their visual acuity was improved than that before the operation. Due to severe proliferative vitreoretinopathy (PVR), failure occurred in 3 eyes. CONCLUSIONS The main advantage of vitrectomy is the better intra-operative sight to the peripheral retinal breaks, removal of retinal traction and the low rate of PVR after vitrectomy. Vitrectomy for complicated type of pseudophakic retinal detachment can improve the success rate of the retinal detachment surgery and the visual acuity outcome.
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149
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Dai H, Zhao J, Tan WS, Yang YZ. [Adaptation of insect cells(BTI-Tn-5B1-4) to serum-free culture]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2000; 16:232-4. [PMID: 10976335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The insect cells(BTI-Tn-5B1-4) were adapted, from the medium supplemented with 5% FBS, via 3%, 2%, 1% FBS, to grow in serum-free medium by sequential adaptation for about three months. After adaptation, the cells could successfully grow in the specifically designed serum-free medium with the viability above 90%. In addition, the effect of FBS concentrations and inoculum sizes on the insect cell growth was also investigated.
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150
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Roberts CJ, Nelson B, Marton MJ, Stoughton R, Meyer MR, Bennett HA, He YD, Dai H, Walker WL, Hughes TR, Tyers M, Boone C, Friend SH. Signaling and circuitry of multiple MAPK pathways revealed by a matrix of global gene expression profiles. Science 2000; 287:873-80. [PMID: 10657304 DOI: 10.1126/science.287.5454.873] [Citation(s) in RCA: 726] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Genome-wide transcript profiling was used to monitor signal transduction during yeast pheromone response. Genetic manipulations allowed analysis of changes in gene expression underlying pheromone signaling, cell cycle control, and polarized morphogenesis. A two-dimensional hierarchical clustered matrix, covering 383 of the most highly regulated genes, was constructed from 46 diverse experimental conditions. Diagnostic subsets of coexpressed genes reflected signaling activity, cross talk, and overlap of multiple mitogen-activated protein kinase (MAPK) pathways. Analysis of the profiles specified by two different MAPKs-Fus3p and Kss1p-revealed functional overlap of the filamentous growth and mating responses. Global transcript analysis reflects biological responses associated with the activation and perturbation of signal transduction pathways.
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