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Liang J, Zhang H, Hua B, Wang H, Wang J, Han Z, Sun L. Allogeneic mesenchymal stem cells transplantation in treatment of multiple sclerosis. Mult Scler 2009; 15:644-6. [PMID: 19389752 DOI: 10.1177/1352458509104590] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Multiple sclerosis (MS) is a chronic autoimmune disorder of the central nervous system. Umbilical cord derived mesenchymal stem cells are immunosuppressive. We transplanted mesenchymal stem cells in a patient with refractory progressive MS, and the disease course was stabilized after the transplantation. We postulate that mesenchymal stem cells have a potent immunosuppressive effect in vivo.
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Ansell D, Radko IP, Han Z, Rodriguez FJ, Bozhevolnyi SI, Grigorenko AN. Hybrid graphene plasmonic waveguide modulators. Nat Commun 2015; 6:8846. [PMID: 26554944 PMCID: PMC5227092 DOI: 10.1038/ncomms9846] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 10/09/2015] [Indexed: 12/23/2022] Open
Abstract
The unique optical and electronic properties of graphene make possible the fabrication of novel optoelectronic devices. One of the most exciting graphene characteristics is the tunability by gating which allows one to realize active optical devices. While several types of graphene-based photonic modulators have already been demonstrated, the potential of combining the versatility of graphene with subwavelength field confinement of plasmonic waveguides remains largely unexplored. Here we report fabrication and study of hybrid graphene-plasmonic waveguide modulators. We consider several types of modulators and identify the most promising one for telecom applications. The modulator working at the telecom range is demonstrated, showing a modulation depth of >0.03 dB μm(-1) at low gating voltages for an active device area of just 10 μm(2), characteristics which are already comparable to those of silicon-based waveguide modulators while retaining the benefit of further device miniaturization. Our proof-of-concept results pave the way towards on-chip realization of efficient graphene-based active plasmonic waveguide devices for optical communications.
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Edwards WT, Ordway NR, Zheng Y, McCullen G, Han Z, Yuan HA. Peak stresses observed in the posterior lateral anulus. Spine (Phila Pa 1976) 2001; 26:1753-9. [PMID: 11493846 DOI: 10.1097/00007632-200108150-00005] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN The stress distributions within cadaveric lumbar intervertebral discs were measured for a range of loading conditions. OBJECTIVES To examine the distribution of stress across the area of the intervertebral disc and to compare regional variations in peak stress during compression loading with various flexion angles. SUMMARY OF BACKGROUND DATA The rate of disc degeneration and the occurrence of low back disorders increase with higher mechanical loading of the spine. The largest peak stresses occur in the anulus. METHODS Human lumbar L2--L3 and L4--L5 cadaver functional spinal units were obtained and tested. The distribution of disc stress was measured using a pressure probe with loads applied, pure compression and compression with 5 degrees of either flexion or extension. RESULTS Stress profiles were recorded across the intervertebral disc at a compressive force of 1000 N and each of the three flexion-extension angles. The highest values (2.99 +/- 1.31 MPa) were measured during extension-compression lateral to the midline of the disc in the posterior anulus. The pressure in the nucleus was relatively unchanged by flexion angle remaining about 1.00 MPa for a 1000-N compression. CONCLUSIONS Pressure measurements of the cadaveric nucleus have been used to validate models of lumbar spine loading and to evaluate the risk of low back injury and disc herniation. Previous observations limited to midsagittal measurements of the nucleus did not identify the regions of highest stress. The highest values observed here within the posterolateral anulus correspond to common sites of disc degeneration and herniation.
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Adachi S, Obaya AJ, Han Z, Ramos-Desimone N, Wyche JH, Sedivy JM. c-Myc is necessary for DNA damage-induced apoptosis in the G(2) phase of the cell cycle. Mol Cell Biol 2001; 21:4929-37. [PMID: 11438650 PMCID: PMC87219 DOI: 10.1128/mcb.21.15.4929-4937.2001] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The c-myc proto-oncogene encodes a transcription factor that participates in the regulation of cellular proliferation, differentiation, and apoptosis. Ectopic overexpression of c-Myc has been shown to sensitize cells to apoptosis. We report here that cells lacking c-Myc activity due to disruption of the c-myc gene by targeted homologous recombination are defective in DNA damage-initiated apoptosis in the G(2) phase of the cell cycle. The downstream effector of c-Myc is cyclin A, whose ectopic expression in c-myc(-/-) cells rescues the apoptosis defect. The kinetics of the G(2) response indicate that the induction of cyclin A and the concomitant activation of Cdk2 represent an early step during commitment to apoptosis. In contrast, expression of cyclins E and D1 does not rescue the apoptosis defect, and apoptotic processes in G(1) phase are not affected in c-myc(-/-) cells. These observations link DNA damage-induced apoptosis with cell cycle progression and implicate c-Myc in the functioning of a subset of these pathways.
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Han Z, Boyle DL, Shi Y, Green DR, Firestein GS. Dominant-negative p53 mutations in rheumatoid arthritis. ARTHRITIS AND RHEUMATISM 1999; 42:1088-92. [PMID: 10366100 DOI: 10.1002/1529-0131(199906)42:6<1088::aid-anr4>3.0.co;2-e] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Studies were performed to determine if p53 mutations identified in rheumatoid arthritis (RA) synovial tissue are dominant negative. METHODS Site-directed mutagenesis was used to produce 2 RA-derived mutants: asparagine-->serine at codon 239 (N239S) and arginine-->stop at codon 213 R213*). HS68 dermal fibroblasts were transfected with either empty vector, wild-type p53 cDNA (wt), or the N239S or R213* mutant p53 cDNA clones. Interleukin-6 (IL-6) and bax gene expression were determined by Northern blot analysis. Bax transcription was determined using a bax promoter/reporter gene construct (bax-luc). RESULTS Transfection of HS68 cells with wt increased bax mRNA levels. This process was blocked by cotransfection with either mutant. The mutant p53 genes also increased IL-6 gene expression. Low levels of bax promoter activity were detected in HS68 cells co-transfected with bax-luc and empty vector, N239S, or R213*, indicating that the RA mutants lacked transcriptional activity. Transfection with wt and bax-luc led to a 10-fold increase in luciferase expression. When the wt gene was cotransfected with either of the mutants, there was a dose-dependent inhibition of bax promoter activity. CONCLUSION These data indicate that at least 2 of the p53 mutants identified in RA joint samples are dominant negative and suppress endogenous wild-type p53 function.
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MESH Headings
- Arthritis, Rheumatoid/genetics
- Arthritis, Rheumatoid/pathology
- Blotting, Northern
- Blotting, Western
- Cells, Cultured
- DNA Primers/chemistry
- DNA, Complementary/genetics
- Epidermal Cells
- Epidermis/enzymology
- Fibroblasts/cytology
- Fibroblasts/enzymology
- Genes, Dominant/genetics
- Genes, p53/genetics
- Humans
- Luciferases/metabolism
- Mutagenesis, Site-Directed
- Point Mutation
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-bcl-2
- RNA, Messenger/biosynthesis
- Reverse Transcriptase Polymerase Chain Reaction
- Synovial Membrane/chemistry
- Synovial Membrane/pathology
- Transfection
- bcl-2-Associated X Protein
- beta-Galactosidase/metabolism
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Han Z, Chatterjee D, He DM, Early J, Pantazis P, Wyche JH, Hendrickson EA. Evidence for a G2 checkpoint in p53-independent apoptosis induction by X-irradiation. Mol Cell Biol 1995; 15:5849-57. [PMID: 7565737 PMCID: PMC230836 DOI: 10.1128/mcb.15.11.5849] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The p53 tumor suppressor gene is thought to be required for the induction of programmed cell death (apoptosis) initiated by DNA damage. We show here, however, that the human promyelocytic leukemia cell line HL-60, which is known to be deficient in p53 because of large deletions in the p53 gene, can be induced to undergo apoptosis following X-irradiation. We demonstrate that the decision to undergo apoptosis in this cell line appears to be made at a G2 checkpoint. In addition, we characterize an HL-60 variant, HCW-2, which is radioresistant. HCW-2 cells display DNA damage induction and repair capabilities identical to those of the parental HL-60 cell line. Thus, the difference between the two cell lines appears to be that X-irradiation induces apoptosis in HL-60, but not in HCW-2, cells. Paradoxically, HCW-2 cells display high levels of expression of bax, which enhances apoptosis, and no longer express bcl-2, which blocks apoptosis. HCW-2 cells' resistance to apoptosis may be due to the acquisition of expression of bcl-XL, a bcl-2-related inhibitor of apoptosis. In summary, apoptosis can be induced in X-irradiated HL-60 cells by a p53-independent mechanism at a G2 checkpoint, despite the presence of endogenous bcl-2. The resistance shown by HCW-2 cells suggests that bcl-XL can block this process.
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Wang Z, Han Z, Geng D, Zhang Z. Synthesis, characterization and microwave absorption of carbon-coated Sn nanorods. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.02.056] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sun H, Pu J, Chen F, Wang J, Han Z. Multiple ATP-binding cassette transporters are involved in insecticide resistance in the small brown planthopper, Laodelphax striatellus. INSECT MOLECULAR BIOLOGY 2017; 26:343-355. [PMID: 28299835 DOI: 10.1111/imb.12299] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
ATP-binding cassette (ABC) transporters are membrane-bound proteins involved in the movement of various substrates, including drugs and insecticides, across the lipid membrane. Demonstration of the role of human ABC transporters in multidrug resistance has led to speculation that they might be an important mechanism controlling the fate of insecticides in insects. However, the role of ABC transporters in insects remains largely unknown. The small brown planthopper, Laodelphax striatellus Fallén, has developed resistance to most of the insecticides used for its control. Our goals were to identify the ABC transporters in La. striatellus and to examine their involvement in resistance mechanisms, using related strains resistant to chlorpyrifos, deltamethrin and imidacloprid, compared with the susceptible strain. Based on the transcriptome of La. striatellus, 40 full-length ABC transporters belonging to the ABCA-ABCH subfamilies were identified. Quantitative PCR revealed that over 20% of genes were significantly up-regulated in different resistant strains, and eight genes from the ABCB/C/D/G subfamilies were up-regulated in all three resistant strains, compared with the susceptible strain. Furthermore, synergism studies showed verapamil significantly enhanced insecticide toxicity in various resistant strains but not in the susceptible strain. These results suggest that ABC transporters might be involved in resistance to multiple insecticides in La. striatellus.
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Yuan L, Han Z, Chang JK, Han JS. Accelerated release and production of orphanin FQ in brain of chronic morphine tolerant rats. Brain Res 1999; 826:330-4. [PMID: 10224316 DOI: 10.1016/s0006-8993(99)01337-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Orphanin FQ has been shown to possess anti-opioid activity at supraspinal level. Our previous work revealed that chronic morphine tolerance could be reversed by intracerebroventricular (i.c.v.) injection of OFQ IgG to rats. In this study, we used radioimmunoassay (RIA) to assess the changes of Orphanin FQ immunoreactivity (OFQ-ir) in cerebroventricular perfusate, periaqueductal gray (PAG) and amygdala of rats made tolerance to morphine (10-60 mg/kg, s.c., t.i.d., for 5 days). The results indicated that: (1) In rats administrated with morphine for 3 and 5 days, the content of OFQ-ir in cerebroventricular perfusate increased by 25% and 52% over the NS control group. (2) The content of OFQ-ir in PAG of rats receiving 1d, 3d and 5d injections of morphine showed an increase of 17%, 48% and 81% respectively over NS group. (3) The content of OFQ-ir in amygdala of rats given 3d and 5d of morphine showed a 36% and 55% increase compared with corresponding control group. It is suggested that continuous use of high doses of morphine accelerated the release and biosynthesis of OFQ in rat brain to antagonize the effect of opioids, which may play a role in the development of morphine tolerance, and that brain OFQ may serve as a delayed negative feedback control on opioid analgesia.
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Abstract
The molecular mechanisms for regulating water balance in many tissues are unknown. Like the kidney, the eye contains multiple water channel proteins (aquaporins) that transport water through membranes, including two (AQP1 and AQP4) in the ciliary body, the site of aqueous humor production. Previous results from our laboratory demonstrated that water channel activity of AQP1 was significantly increased by protein kinase A (PKA) activators such as cyclic-AMP (cAMP) and forskolin. The purpose of this study is to determine whether PKA-dependent protein phosphorylation is involved in the regulation of water channel activity of AQP1. Results presented here suggest that catalytic subunit of protein kinase A significantly increased the amount of phosphorylated AQP1 protein. In addition, these results indicated that cAMP-responsive redistribution of AQP1 may be regulated by phosphorylation of AQP1. Moreover, they provide new insights on the molecular mechanisms for regulating water balance in several tissues involving rapid water transport such as ciliary epithelium. In addition, they suggest important potential roles for AQP1 in several clinical disorders involving rapid water transport such as glaucoma.
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Jarde A, Lutsiv O, Park CK, Barrett J, Beyene J, Saito S, Dodd JM, Shah PS, Cook JL, Biringer AB, Giglia L, Han Z, Staub K, Mundle W, Vera C, Sabatino L, Liyanage SK, McDonald SD. Preterm birth prevention in twin pregnancies with progesterone, pessary, or cerclage: a systematic review and meta-analysis. BJOG 2017; 124:1163-1173. [DOI: 10.1111/1471-0528.14513] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/28/2016] [Indexed: 12/14/2022]
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Han Z, Bhalla K, Pantazis P, Hendrickson EA, Wyche JH. Cif (Cytochrome c efflux-inducing factor) activity is regulated by Bcl-2 and caspases and correlates with the activation of Bid. Mol Cell Biol 1999; 19:1381-9. [PMID: 9891071 PMCID: PMC116066 DOI: 10.1128/mcb.19.2.1381] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The cytosolic factor Cif (cytochrome c-efflux inducing factor) was activated by the apoptosis inducers staurosporine and anti-Fas antibodies and rapidly induced the efflux of cytochrome c from purified human mitochondria. HL-60 cells that stably overexpressed a bcl-2 cDNA transgene (Bcl-2:HL-60 cells) contained mitochondria and a cytosol that were resistant to exogenous Cif and that lacked detectable endogenous Cif activity, respectively. Therefore, Bcl-2 overexpression negated Cif activity and suggested that the requirement for Cif resides upstream of Bcl-2 on the apoptotic signal transduction pathway. The addition of purified caspase 3, caspase 7, or caspase 8 to the cytosolic extract from Bcl-2:HL-60 cells, however, restored Cif activity, demonstrating that the inhibition of Cif by Bcl-2 overexpression could be overcome by activated caspases. Moreover, the addition of purified caspases to cytosolic extracts prepared from parental HL-60 cells was also sufficient to cause Cif activation, suggesting that caspases might be required for Cif activation. Consistent with these observations, Fas-induced apoptosis in Jurkat cells resulted in caspase 8 activation and subsequently in activation of Cif. Finally, we demonstrate that the activation of Cif correlated with the activation of the Bcl-2 family member Bid by caspases and that Cif activity was selectively neutralized by anti-Bid antibodies. Taken together, these results indicate that Cif is identical to Bid and that it can be inhibited by Bcl-2 and activated by caspases. Thus, Cif (Bid) is an important biological regulator for the transduction of apoptotic signals.
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Abstract
The matrix metalloproteinase (MMP) enzymes MMP-9, have relevance to chronic structural airway changes in asthma, which can be generated by structural and inflammatory cells, and have the ability to degrade proteoglycans and thus potentially enhance airway fibrosis and smooth muscle proliferation through their ability to release and activate latent, matrix-bound growth factors. Immunostaining for MMP-9 was undertaken in acetone-fixed and glycolmethacrylate-embedded endobronchial biopsy specimens obtained by fibreoptic bronchoscopy under local anaesthesia. The findings from 30 asthmatic subjects were compared with those from 18 chronic obstructive pulmonary disease (COPD) subjects and 10 healthy controls. Meanwhile, pulmonary function test and airway responsiveness were performed. Immunoreactivity for MMP-9 was assessed by an image analysis system. The biopsy specimens from asthmatic subjects contained significantly more eosinophils (P < 0.001) than those from COPD subjects, and healthy control did not contain eosinophils. MMP-9 immunoreactivity could be identified in endobronchial biopsy specimens from all the asthmatic subjects and 40% ofthe COPD subjects, but could not be identified in healthy controls. Gelatinase B (MMP-9) immunoreactivity was located in bronchial epithelium and extracellular matrix in submucosa, prominent in denuded epithelium. The immunohistochemical score for MMP-9 was significantly correlated with eosinophilic number in bronchial mucosa. FEV1% predicted FEV1/FVC (%) (r = 0.52, 0.41, 0.37, respectively P < 0.01 did not correlate with PD20 FEV1 from asthmatic subjects. MMP-9 is expressed by bronchial epithelium and may be a important factor for eosinophil infiltraed into airway from asthma subjects.
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Patil RV, Han Z, Wax MB. Regulation of water channel activity of aquaporin 1 by arginine vasopressin and atrial natriuretic peptide. Biochem Biophys Res Commun 1997; 238:392-6. [PMID: 9299519 DOI: 10.1006/bbrc.1997.7310] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Aquaporin 1 (AQP1), a six-transmembrane domain protein that functions as a water channel, is present in many fluid secreting and absorbing tissues such as kidney, brain, heart, and eye. It is believed that among the five known mammalian aquaporins, kidney aquaporin (AQP2) is the only water channel that is regulated by arginine vasopressin (AVP). The present data suggest that AQP1 may also be regulated by AVP. The application of AVP to Xenopus oocytes injected with AQP1 cRNA increased the membrane permeability to water. In addition, our data reveal that atrial natriuretic peptide (ANP), a peptide hormone that plays an important role in the regulation of body fluid homeostasis, blocks the AQP1-mediated increase in water permeability. Incubation with 8-bromo-cAMP or direct 8-bromo-cAMP injection into oocytes expressing AQP1 cRNA significantly increased membrane permeability to water, suggesting that stimulation of AQP1 activity by AVP may involve a cAMP-dependent mechanism. Regulation of water permeability by AVP and ANP has potential relevance to active water transport in a variety of tissues that express AQP1 including kidney, brain, and eye.
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Wang W, Tanaka Y, Han Z, Higuchi CM. Proliferative response of mammary glandular tissue to formononetin. Nutr Cancer 1995; 23:131-40. [PMID: 7644382 DOI: 10.1080/01635589509514369] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Dietary phytoestrogens have been implicated in infertility among ruminants and may relate to human breast cancer risk. Formononetin is an isoflavonoid phytoestrogen found in animal fodder and in certain human foodstuffs. To investigate a possible mechanism by which phytoestrogens might influence mammary carcinogenesis, this study examined the capacity of formononetin to stimulate mammary gland proliferation. Formononetin was administered to castrated female BALB/c mice by daily subcutaneous injection; then mammary gland proliferation and estrogen receptor expression were quantified, and plasma prolactin levels were measured. A preliminary dose-finding study demonstrated an estrogenic effect on vaginal cytology when formononetin was injected at 40 mg/kg sc. Peak plasma concentrations of 2.5 +/- 0.8 (SD) micrograms/ml at two hours and peak mammary tissue concentrations of 2.0 +/- 0.2 ng/mg tissue at four hours were noted after a single injection at this minimally bioactive dose. Among animals treated with formononetin at 40 mg/kg/day for five days, mammary gland proliferation was enhanced 3.3-fold over saline-treated controls and was comparable to that of animals treated with estradiol-17 beta at 1 microgram/kg/day for five days. Mammary tissue estrogen receptor expression was 2-fold higher among the formononetin-treated animals (P < 0.01 vs. saline-treated controls), and plasma prolactin concentrations were increased 1.7-fold (P < 0.001 vs. saline-treated controls). In subsequent in vitro binding studies, formononetin competitively bound murine mammary estrogen receptors, but with a relative binding affinity 15,000 times less potent than that of estradiol-17 beta. The results demonstrate an ability of formononetin to support mammary gland proliferation. However, the estrogenic potency of formononetin appears extremely weak compared with that of estradiol-17 beta and is roughly proportional to estrogen receptor-binding capacity.
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Han Z, Johnston C, Reeves WH, Carter T, Wyche JH, Hendrickson EA. Characterization of a Ku86 variant protein that results in altered DNA binding and diminished DNA-dependent protein kinase activity. J Biol Chem 1996; 271:14098-104. [PMID: 8662896 DOI: 10.1074/jbc.271.24.14098] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Three proteins known to play a critical role in mammalian DNA double-strand break repair and lymphoid V(D)J recombination are the autoantigens Ku86 and Ku70 and a 465-kDa serine/threonine protein kinase catalytic subunit (DNA-PKcs). These proteins physically associate to form a complex (DNA.PK) with DNA-dependent protein kinase activity. In this study, we demonstrate using electrophoretic mobility shift assays (EMSAs) that the nuclear DNA end-binding activity of Ku is altered in the human promyelocytic leukemic HL-60 cell line. Western blot and EMSA supershift analyses revealed that HL-60 cells expressed both full-length and variant Ku86 proteins. However, a combined EMSA and immunoanalysis revealed that the Ku heterodimers complexed with DNA in HL-60 cells contained only the variant Ku86 proteins. Finally, UV cross-linking experiments and DNA.PK assays demonstrated that the Ku complexes containing variant Ku86 had a greatly reduced ability to interact with DNA-PKcs and that consequently HL-60 cells had severely diminished DNA.K activity. These data provide important insights into the interaction between Ku and DNA-PKcs and into the role of DNA.PK in DNA double-strand break repair.
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Magid LJ, Han Z, Li Z, Butler PD. Tuning the Contour Lengths and Persistence Lengths of Cationic Micelles: The Role of Electrostatics and Specific Ion Binding. J Phys Chem B 2000. [DOI: 10.1021/jp994477c] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hou J, Qi H, Zhang M, Ma L, Liu H, Han Z, Meng L, Yang S, Zhang S, Yu B, Jang IK. Development of lipid-rich plaque inside bare metal stent: possible mechanism of late stent thrombosis? An optical coherence tomography study. Heart 2010; 96:1187-90. [DOI: 10.1136/hrt.2010.194381] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Juo SH, Han Z, Smith JD, Colangelo L, Liu K. Common polymorphism in promoter of microsomal triglyceride transfer protein gene influences cholesterol, ApoB, and triglyceride levels in young african american men: results from the coronary artery risk development in young adults (CARDIA) study. Arterioscler Thromb Vasc Biol 2000; 20:1316-22. [PMID: 10807748 DOI: 10.1161/01.atv.20.5.1316] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/1999] [Accepted: 12/29/1999] [Indexed: 11/16/2022]
Abstract
The microsomal triglyceride transfer protein (MTP) plays a key role in the assembly of apolipoprotein B (apoB)-containing lipoproteins. We investigated the relation between lipid profiles and a common functional polymorphism (-493G/T) of the MTP gene in a large sample of young black men in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. We performed serial cross-sectional analyses on lipids of 586 black men in 5 exams over 10 years of follow-up. Total cholesterol, LDL cholesterol, and apoB levels were very similar between the GT and GG genotypes; therefore, the GT and GG genotypes were combined as 1 group when the 3 phenotypes were analyzed. The results from ANCOVA showed that the TT group (prevalence 7%) had higher levels of apoB-related lipids than did the GT+GG group: the difference in total cholesterol ranged from 2 (P=0.79) to 19 (P=0.002) mg/dL in exams 1 to 5; the difference in LDL cholesterol ranged from 10 (P=0.14) to 17 (P=0.003) mg/dL in exams 1 to 4, but in examination 5, the difference became negligible. The TT group had higher levels of apoB, measured in only 2 exams, by 6 (P=0.12) and 9 (P=0.03) mg/dL. The TT group had higher levels of triglycerides than did the TG or GG group by 3 to 34 (P=0.02 to approximately 0.003) mg/dL in all 5 exams. HDL cholesterol and apolipoprotein A-I levels were similar among the 3 genotypes. Our serial cross-sectional analyses indicated that the TT genotype was associated with higher levels of total cholesterol, LDL cholesterol, triglycerides, and apoB in young black men. The broad effect of this polymorphism on several atherogenic traits suggests that the MTP gene could be influential in atherosclerosis.
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Han Z, Uehira S, Shinokubo H, Oshima K. TiCl4-n-Bu4NX (X = I, Br, and Cl) combination-induced coupling of alpha,beta-unsaturated ketones with aldehydes. J Org Chem 2001; 66:7854-7. [PMID: 11701046 DOI: 10.1021/jo016054o] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A three-component coupling reaction between vinyl ketones, aldehydes, and halides has been developed with TiCl(4)-n-Bu(4)NX combined reagents. Treatment of vinyl ketones with a TiCl(4)-n-Bu(4)NI combination followed by an addition of a variety of aldehydes provides syn-alpha-iodomethyl-beta-hydroxy ketones with high stereoselectivity. Methyltriphenylphosphonium iodide as well as n-Bu(4)NI acts efficiently as a halide source. The combination of TiCl(4)-n-Bu(4)NBr provides the corresponding bromo compounds in good yields. syn-alpha-Chloromethyl-beta-hydroxy ketones are obtained with the TiCl(4)-n-Bu(4)NCl combination. A competitive experiment reveals that the order of relative reactivity of the combinations is TiCl(4)-n-Bu(4)NI > TiCl(4)-n-Bu(4)NBr > TiCl(4)-n-Bu(4)NCl.
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Zhang Y, Liu M, Shuidong O, Hu QL, Guo DC, Chen HY, Han Z. Detection and identification of avian, duck, and goose reoviruses by RT-PCR: goose and duck reoviruses are part of the same genogroup in the genus Orthoreovirus. Arch Virol 2006; 151:1525-38. [PMID: 16502280 DOI: 10.1007/s00705-006-0731-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2005] [Accepted: 01/19/2006] [Indexed: 11/26/2022]
Abstract
A reverse transcription-polymerase chain reaction (RT-PCR) procedure for the detection of avian, duck, and goose reovirus (ARV, DRV, and GRV) RNA from cell culture supernatant and clinical samples was established. Based on multiple sequence alignment, a pair of degenerate primers was selected and synthesized. The amplified, cloned, and sequenced 598-base-pair products from the sigmaA-encoding gene fragment from 16 isolates (ranging over 30 years) indicated that the primer regions were well conserved. The sensitivity of this method was determined to be 10(-2) PFU. The specificity of the RT-PCR method was determined by testing specimens containing avian influenza A viruses, Newcastle disease virus, and infectious bronchitis virus, all of which yielded negative results with no discernible background. The efficiency of the system for detection of ARV, DRV, and GRV directly in 71/83 clinical samples was confirmed. The nucleotide sequence analysis indicated that DRV and GRV isolated from China in different locales and years were closely related, showing 97.4-100% homology to each other, but with only 86.7-88.5% identity to DRV 89026. The nucleotide and amino acid sequence identities in the amplified sigmaA-encoding gene were 74.2-78.4% and 86.9-92.0%, respectively, between duck/goose and chicken species. Phylogenetic analysis indicated that GRV and DRV aggregated into the same specified genogroup within subgroup II of the genus Orthoreovirus and are more closely related to ARV than to Nelson Bay virus. Overall, this study developed a sensitive and specific technique for the identification ARV, DRV, and GRV, and sequencing analysis has enhanced our understanding of the evolutionary relationship between ARV, DRV, and GRV.
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Han Z, Pantazis P, Lange TS, Wyche JH, Hendrickson EA. The staurosporine analog, Ro-31-8220, induces apoptosis independently of its ability to inhibit protein kinase C. Cell Death Differ 2000; 7:521-30. [PMID: 10822275 DOI: 10.1038/sj.cdd.4400681] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A series of bisindolylmaleimide (Bis) compounds were designed as analogs of the natural compound staurosporine (STS), which is a potent inducer of apoptosis. Many of the Bis analogs appear to be highly selective inhibitors of the protein kinase C (PKC) family, including PKC-alpha, -beta, -gamma, -delta, -epsilon, and -zeta, unlike STS, which is an inhibitor of a broad spectrum of protein kinases. In this report we describe the effects of the Bis analogs, Bis-I, Bis-II, Bis-III and Ro-31-8220 on the survival and proliferation of HL-60 cells, which have been widely used as a model cell system for studying the biological roles of PKC. Treatment of HL-60 cells with Bis-I, Bis-II, Bis-III, or Ro-31-8220 blocked phosphorylation of the PKC target protein Raf-1 with equal potency but did not appear to affect the general phosphorylation of proteins by other kinases. However, the biological effects of the Bis compounds were different: Bis-I and Bis-II had no observable effects on either cell survival or proliferation; Bis-III inhibited cell proliferation but not survival, whereas Ro-31-8220 induced apoptosis. These results indicated that the members of the PKC family which could be inhibited by the Bis analogs were required neither for survival nor proliferation of HL-60 cells. Analyses of cells treated with Ro-31-8220 showed that the apoptotic effect of Ro-31-8220 on HL-60 cells was mediated by a well-characterized transduction process of apoptotic signals: i.e., mitochondrial cytochrome c efflux and the activation of caspase-3 in the cytosol. Moreover, the ability of Ro-31-8220 to induce apoptotic activation was completely inhibited by the over-expression of the apoptotic suppressor gene, Bcl-2, in the cells. Interestingly, proliferation of the Bcl-2-over-expressing cells was still sensitive to the presence of Ro-31-8220, suggesting that the inhibitory effects of Ro-31-8220 on viability and cell proliferation were mediated by different mechanisms. In particular, the apoptotic effect of Ro-31-8220 on cells was not altered by the presence of an excess amount of the other Bis analogs, suggesting that this effect is mediated by a factor(s) other than PKC or by a mechanism which was not saturable by the other Bis analogs. Finally, structure-function analyses of compounds related to Ro-31-8220 revealed that a thioamidine prosthetic group in Ro-311-8220 was largely responsible for its apoptotic activity.
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Han Z, Freltoft T. The mechanical deformation process for preparing Ag-sheathed BiSrCaCuO superconducting tapes. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0964-1807(94)90007-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Jarde A, Lutsiv O, Park CK, Beyene J, Dodd JM, Barrett J, Shah PS, Cook JL, Saito S, Biringer AB, Sabatino L, Giglia L, Han Z, Staub K, Mundle W, Chamberlain J, McDonald SD. Effectiveness of progesterone, cerclage and pessary for preventing preterm birth in singleton pregnancies: a systematic review and network meta-analysis. BJOG 2017; 124:1176-1189. [PMID: 28276151 DOI: 10.1111/1471-0528.14624] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2017] [Indexed: 11/30/2022]
Abstract
BACKGROUND Preterm birth (PTB) is the leading cause of infant death, but it is unclear which intervention is best to prevent it. OBJECTIVES To compare progesterone, cerclage and pessary, determine their relative effects and rank them. SEARCH STRATEGY We searched Medline, EMBASE, CINAHL, Cochrane CENTRAL and Web of Science (to April 2016), without restrictions, and screened references of previous reviews. SELECTION CRITERIA We included randomised trials of progesterone, cerclage or pessary for preventing PTB in women with singleton pregnancies at risk as defined by each study. DATA COLLECTION AND ANALYSIS We extracted data by duplicate using a piloted form and performed Bayesian random-effects network meta-analyses and pairwise meta-analyses. We rated evidence quality using GRADE, ranked interventions using SUCRA and calculated numbers needed to treat (NNT). MAIN RESULTS We included 36 trials (9425 women; 25 low risk of bias trials). Progesterone ranked first or second for most outcomes, reducing PTB < 34 weeks [odds ratio (OR) 0.44; 95% credible interval (CrI) 0.22-0.79; NNT 9; low quality], <37 weeks (OR 0.58; 95% CrI 0.41-0.79; NNT 9; moderate quality), and neonatal death (OR 0.50; 95% CrI 0.28-0.85; NNT 35; high quality), compared with control, in women overall at risk. We found similar results in the subgroup with previous PTB, but only a reduction of PTB < 34 weeks in women with a short cervix. Pessary showed inconsistent benefit and cerclage did not reduce PTB < 37 or <34 weeks. CONCLUSIONS Progesterone was the best intervention for preventing PTB in singleton pregnancies at risk, reducing PTB < 34 weeks, <37 weeks, neonatal demise and other sequelae. TWEETABLE ABSTRACT Progesterone was better than cerclage and pessary to prevent preterm birth, neonatal death and more in network meta-analysis.
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Jin P, Han Z, Cai Z, Wu Y, Ren Y. Simultaneous determination of 10 mycotoxins in grain by ultra-high-performance liquid chromatography–tandem mass spectrometry using13C15-deoxynivalenol as internal standard. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2010; 27:1701-13. [DOI: 10.1080/19440049.2010.517222] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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