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Zhang SX, Sima J, Shao C, Fant J, Chen Y, Rohrer B, Gao G, Ma JX. Plasminogen kringle 5 reduces vascular leakage in the retina in rat models of oxygen-induced retinopathy and diabetes. Diabetologia 2004; 47:124-31. [PMID: 14666366 DOI: 10.1007/s00125-003-1276-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Revised: 06/06/2003] [Indexed: 10/26/2022]
Abstract
AIMS/HYPOTHESIS Retinal vascular leakage is an early pathological feature in diabetic retinopathy and can lead to macular oedema and loss of vision. Previously we have shown that plasminogen kringle 5 (K5), an angiogenic inhibitor, inhibits retinal neovascularisation in the rat model of oxygen-induced retinopathy (OIR). The purpose of this study was to examine the effect of K5 on vascular leakage in the retina. METHODS Neonatal rats were exposed to hyperoxia to induce OIR. Diabetes was induced in adult rats by injecting streptozotocin. Vascular permeability was measured by Evans blue method. Expression of vascular endothelial growth factor (VEGF) was evaluated using immunohistochemistry and western blot analysis. RESULTS Rats with OIR and diabetes showed abnormal vascular hyperpermeability in the retina and iris. Intravitreal injection of K5, reduced vascular permeability in both animal models, but did not affect permeability in normal rats. K5 reduced vascular permeability at doses substantially lower than that required for inhibition of retinal neovascularisation. The K5-induced reduction in vascular permeability correlated with its down-regulation of VEGF expression in the retina. Moreover, K5 inhibited IGF-1-induced hyperpermeability, which is known to arise through up-regulation of endogenous VEGF expression. However, K5 had no effect on the hyperpermeability induced by injection of exogenous VEGF. CONCLUSIONS/INTERPRETATION Very low doses of K5 reduce pathological vascular leakage in the retina. K5 thus has therapeutic potential in the treatment of diabetic macular oedema. This effect can be ascribed, at least in part, to the down-regulation of endogenous VEGF expression.
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Abdullah ASM, Guan FQ, Zhuo J, Zhang SX, Geng W, Ebrahim SH. Need, readiness and opportunities for family HIV/AIDS intervention in China. Int J STD AIDS 2003; 14:642-3. [PMID: 14511506 DOI: 10.1258/095646203322301158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Gao G, Shao C, Zhang SX, Dudley A, Fant J, Ma JX. Kallikrein-binding protein inhibits retinal neovascularization and decreases vascular leakage. Diabetologia 2003; 46:689-98. [PMID: 12743698 DOI: 10.1007/s00125-003-1085-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2002] [Revised: 02/10/2003] [Indexed: 10/20/2022]
Abstract
AIMS/HYPOTHESIS Kallikrein-binding protein (KBP) is a serine proteinase inhibitor (serpin). It specifically binds to tissue kallikrein and inhibits kallikrein activity. Our study was designed to test its effects on retinal neovascularization and vascular permeability. METHODS Endothelial cell proliferation was determined by [(3)H] thymidine incorporation assay and apoptosis quantified by Annexin V staining and flow cytometry. Effect on retinal neovascularization was determined by fluorescein angiography and count of pre-retinal vascular cells in an oxygen-induced retinopathy (OIR) model. Vascular permeability was assayed by the Evans blue method. Vascular endothelial growth factor (VEGF) was measured by Western blot analysis and ELISA. RESULTS Kallikrein-binding protein specifically inhibited proliferation and induced apoptosis in retinal capillary endothelial cells. Intravitreal injection of KBP inhibited retinal neovascularization in an OIR model. Moreover, KBP decreased vascular leakage in the retina, iris and choroid in rats with OIR. Blockade of kinin receptors by specific antagonists showed significantly weaker inhibition of endothelial cells, when compared to that of KBP, suggesting that the anti-angiogenic activity of KBP is not through inhibiting kallikrein activity or kinin production. KBP competed with (125)I-VEGF for binding to endothelial cells and down-regulated VEGF production in endothelial cells and in the retina of the OIR rat model. CONCLUSION/INTERPRETATION Kallikrein-binding protein is a multi-functional serpin, and its vascular activities are independent of its interactions with the kallikrein-kinin system. Inhibition of VEGF binding to its receptors and down-regulation of VEGF expression could represent a mechanism for the vascular activities of KBP.
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Zhang WG, Zhang SX, Wu BH. A study on the sectional anatomy of the oculomotor nerve and its related blood vessels with plastination and MRI. Surg Radiol Anat 2002; 24:277-84. [PMID: 12497217 DOI: 10.1007/s00276-002-0052-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2001] [Accepted: 06/01/2002] [Indexed: 11/30/2022]
Abstract
To obtain normal images and sectional anatomical data of the oculomotor nerve and its related arteries, the optimal angles and the length of intracisternal segment of the oculomotor nerve were measured on MPR images. Meanwhile, the relationships between the nerve and the basilar, posterior cerebral, superior cerebellar and posterior communicating arteries were observed from plastination slices, original images, MPR and MIP images. MRI revealed similar results to the plastination sections. The intracisternal segment of oculomotor nerve formed an angle with the posterior plane of the brainstem. The angle was significantly smaller in individuals under 10 and over 50 years old ( P<0.05), and there was no marked difference in the angle between the oculomotor nerve and the median sagittal plane among the different groups ( P>0.05). Shift of the basilar artery was more likely to be found in aged individuals. Most of the posterior cerebral and superior cerebellar arteries were close to the nerve, and a few of them seemed to compress it; for the posterior communicating artery, only the embryonic type was close to or seemed to compress the nerve. MRI is an accurate imaging technique for determination of the relationship of the oculomotor nerve to its related arteries.
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Sha Y, Zhang SX, Liu ZJ, Tan LW, Wu XY, Wan YS, Deng JH, Tang ZS. Computerized 3D-reconstructions of the ligaments of the lateral aspect of ankle and subtalar joints. Surg Radiol Anat 2002; 23:111-4. [PMID: 11469221 DOI: 10.1007/s00276-001-0111-1] [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: 10/25/2022]
Abstract
3D-reconstruction images of the structures of lateral aspect of the ankle and subtalar joints were produced using plastination to make equidistant serial sections of 1.2 mm in thickness. A SGI workstation was employed to reconstruct the structures of the ligaments of the lateral aspect of ankle and subtalar joints in three dimensions. Reconstructed structures were displayed singly, in groups or as a whole, and these were rotated continuously at different velocities in 3D space. Different diameters and angles of the reconstructed structures could be measured easily. Improved results could be achieved with the use of a special sectional anatomical technique, i.e. contours + marching cubes algorithm.
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Zhang SX, Guo Y, Boulianne GL. Identification of a novel family of putative methyltransferases that interact with human and Drosophila presenilins. Gene 2001; 280:135-44. [PMID: 11738826 DOI: 10.1016/s0378-1119(01)00770-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Mutations in the presenilin genes have been shown to cause the majority of cases of early-onset familial Alzheimer's disease (AD). In addition to their role in AD, presenilins are also known to function during development by interacting with the Notch pathway. To determine if presenilins have additional functions during development and AD we have used a yeast two-hybrid approach to search for proteins that can bind to presenilins. Here, we show the identification and characterization of a novel putative methyltransferase (Metl) that interacts with the loop region of Drosophila presenilin as well as human presenilin-1 and presenilin-2, suggesting that this interaction is evolutionarily conserved and functionally important. Metl appears to be a member of a conserved family of methyltransferases that share homology with, but are distinct from, the UbiE family of methyltransferases involved in ubiquinone and menaquinone biosynthesis. In Drosophila, the metl gene gives rise to two major isoforms by alternative splicing that are broadly expressed throughout development and found in the central nervous system in an overlapping pattern with Drosophila presenilin. Finally, we show that two independent dominant adult phenotypes produced by overexpression of presenilin can be enhanced by overexpression of metl in the same tissue. Taken together, these results suggest that presenilin and Metl functionally and genetically interact during development.
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Zhang SX, Cai SQ, Zhao YY. [Studies on the chemical constituents of Asarum longerhizomatosum C. F. Liang et C. S. Yang]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2001; 26:762-3. [PMID: 12776347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
OBJECTIVE To study the chemical constituents of the roots and rhizomes of Asarum longerhizomatosum. METHOD Chromatography and spectral analysis were used to isolate the constituents and elucidate their structures. RESULT Five compounds were isolated from the ethanol extracts of the roots and rhizomes, and identified as asarone(I), beta-sitosterol(II), 2,4,5-trimethoxybenzaldehyde(III), 4-(2,4,5-trimethoxyphenyl)-3-en-butylone(IV) and 3 beta-hydroxystigmast-5-en-7-one(V). CONCLUSION All the compounds were isolated from the plant for the first time, and IV is a new natural product.
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Shinozaki Y, Fukamiya N, Fukushima M, Okano M, Nehira T, Tagahara K, Zhang SX, Zhang DC, Lee KH. Dantaxusins A and B, two new taxoids from Taxus yunnanensis. JOURNAL OF NATURAL PRODUCTS 2001; 64:1073-6. [PMID: 11520230 DOI: 10.1021/np0100643] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Two new taxane diterpenes, dantaxusin A [5 alpha-cinnamoyloxy-2 alpha,7 beta,13 alpha-triacetoxy-2(3-->20)abeo-taxa-4(20),11-diene-9,10-dione (1)] and dantaxusin B [5 alpha-cinnamoyloxy-9 alpha-hydroxy-10 beta,13 alpha-diacetoxytaxa-4(20),11-diene (2)], were isolated from an ethanol extract of the aerial parts of Taxus yunnanensis along with taxuspine B, 2-deacetoxytaxinine J, taxuyunnanine C, taxinine B, taxuspine C, and taxinine NN-4. The structures of 1 and 2 were established on the basis of 1D and 2D NMR and HRMS spectroscopic methods.
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Zhang SX, Ma QJ, Zhao ZH. [Constructing and expression of three zinc-fingers peptide with specific DNA recognition property in Escherichia coli]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2001; 17:406-9. [PMID: 11702697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
For investigating the DNA binding property of classical zinc finger protein Zif268, an in vivo transcription interference experiment was once utilized to develop a genetic selection assay. By screening a library in which the key amino acids of the third zinc finger from Zif268 were randomized, some single fingers with new binding specificity were obtained. In this study, by combining the single fingers, two three-finger peptides cDNA ZF123 and 2ZF123 were constructed by an over-lap PCR technique using the DNA binding domain of Zif268 as the template. After three times PCR, the products were inserted into pUC18 for cloning. The ZF123 and 2ZF123 cDNA were also inserted into pGEX-2T for expression in Escherichia coli after sequencing confirmation. The result showed that the three-finger peptides were expressed at a high level in E. coli JM109. The fusion protein GST-ZF123/2ZF123 have the relative molecular weight of 34.0 kD and consisted about 20% of the total soluble cell protein as detected by SDS-PAGE. After supersonic treatment, the soluble part of the bacterial extract was purified. After two additional thrombin cleavage and Sepharose 4B affinity purification steps, the free three-fingers peptide proteins were also obtained. The construction and obtaining of the three-fingers peptide cDNA and its products will facilitate the in vivo and in vitro DNA binding specificity study and the design of the hybrid transcription factors.
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Yang H, Zhang SX, Xie YB, Wu ZP, Zhu XF, Xu YB. [A study on the colour of natural tooth and porcelain fused to metal crown]. SHANGHAI KOU QIANG YI XUE = SHANGHAI JOURNAL OF STOMATOLOGY 2001; 10:83-4. [PMID: 14994094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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Fukushima M, Fukamiya N, Okano M, Nehira T, Tagahara K, Zhang SX, Zhang DC, Tachibana Y, Bastow KF, Lee KH. Cytotoxity of non-alkaloidal taxane diterpenes from Taxus chinensis against a paclitaxel-resistant cell line. Cancer Lett 2000; 158:151-4. [PMID: 10960764 DOI: 10.1016/s0304-3835(00)00506-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Seven taxane diterpenes were isolated from the EtOH extract of the aerial parts of Taxus chinensis, and evaluated for cytotoxicity against nine human cell lines, including a beta-tublin mutant resistant to paclitaxel. Compound 2, a non-alkaloid-type taxane diterpene, showed significant cytotoxicity in most cell lines, and notably, equipotent against both parental and beta-tublin mutant tumor cell lines.
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Guo Y, Zhang SX, Sokol N, Cooley L, Boulianne GL. Physical and genetic interaction of filamin with presenilin in Drosophila. J Cell Sci 2000; 113 Pt 19:3499-508. [PMID: 10984440 DOI: 10.1242/jcs.113.19.3499] [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: 11/20/2022] Open
Abstract
Presenilins were first identified as causative factors in early onset, familial Alzheimer's Disease (FAD). They are predicted to encode a highly conserved novel family of eight transmembrane domain proteins with a large hydrophilic loop between TM6 and TM7 that is the site of numerous FAD mutations. Here, we show that the loop region of Drosophila and human presenilins interacts with the C-terminal domain of Drosophila filamin. Furthermore, we show that Drosophila has at least two major filamin forms generated by alternative splicing from a gene that maps to position 89E10-89F4 on chromosome 3. The longest form is enriched in the central nervous system and ovaries, shares 41.7% overall amino acid identity with human filamin (ABP-280) and contains an N-terminal actin-binding domain. The shorter form is broadly expressed and encodes an alternatively spliced form of the protein lacking the actin-binding domain. Finally, we show that presenilin and filamin are expressed in overlapping patterns in Drosophila and that dominant adult phenotypes produced by overexpression of presenilin can be suppressed by overexpression of filamin in the same tissue. Taken together, these results suggest that presenilin and filamin functionally interact during development.
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Zhang SX, Underwood M, Landfield A, Huang FF, Gison S, Geddes JW. Cytoskeletal disruption following contusion injury to the rat spinal cord. J Neuropathol Exp Neurol 2000; 59:287-96. [PMID: 10759184 DOI: 10.1093/jnen/59.4.287] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Following experimental spinal cord injury (SCI), there is a delayed loss of neurofilament proteins but relatively little is known regarding the status of other cytoskeletal elements. The purpose of the present study was to compare the extent and time course of the MAP2 loss with that of neurofilament proteins, and to examine tau protein levels and distribution following SCI. Within 1 to 6 hours following SCI, there is rapid loss of MAP2, tau, and nonphosphorylated neurofilament proteins at the injury site. In contrast, the loss of phosphorylated neurofilament proteins was not significant until 1 week postinjury. In addition to the loss of MAP2 protein, there was extensive beading of MAP2-immunoreactive dendrites extending into the white matter. This was most pronounced 1 hour after injury and gradually resolved such that beading was no longer evident 2 weeks after SCI. The time course of beading resolution is similar to that of behavioral recovery following SCI, but the functional significance of the beading remains to be determined. Together, these results demonstrate that there are 2 phases of cytoskeletal disruption following SCI; a rapid loss of MAP2, tau, and nonphosphorylated neurofilament proteins, and a delayed loss of phosphorylated neurofilaments.
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Zhang SX, Feng J, Kuo SC, Brossi A, Hamel E, Tropsha A, Lee KH. Antitumor agents. 199. Three-dimensional quantitative structure-activity relationship study of the colchicine binding site ligands using comparative molecular field analysis. J Med Chem 2000; 43:167-76. [PMID: 10649972 DOI: 10.1021/jm990333a] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Inhibitors of tubulin polymerization interacting at the colchicine binding site are potential anticancer agents. We have been involved in the synthesis of a number of colchicine site agents, such as thiocolchicinoids and allocolchicinoids, which are colchicine analogues, and 2-phenyl-quinolones and 2-aryl-naphthyridinones, which are the amino analogues of cytotoxic antimitotic flavonoids. The most cytotoxic of the latter compounds strongly inhibit binding of radiolabeled colchicine to tubulin, and these agents therefore probably bind in the colchicine site of tubulin. We have applied conventional CoMFA and q(2)-GRS CoMFA to identify the essential structural requirements for increasing the ability of these compounds to form tubulin complexes. The CoMFA model for the training set of 51 compounds yielded cross-validated R(2) (q(2)) values of 0.637 for conventional CoMFA and 0.692 for q(2)-GRS CoMFA. The predictive power of this model was confirmed by successful activity prediction for a test set of 53 compounds with known potencies as inhibitors of tubulin polymerization. The activities of 88% of the compounds were predicted with absolute value of residuals of less than 0.5. The predictive q(2) values were 0.546 for conventional CoMFA and 0.426 for q(2)-GRS CoMFA. The conventional CoMFA model with the highest predictive q(2) (0.546) was analyzed in detail in terms of underlying structure-activity relationships.
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Zhang SX, Bastow KF, Tachibana Y, Kuo SC, Hamel E, Mauger A, Narayanan VL, Lee KH. Antitumor agents. 196. Substituted 2-thienyl-1,8-naphthyridin-4-ones: their synthesis, cytotoxicity, and inhibition of tubulin polymerization. J Med Chem 1999; 42:4081-7. [PMID: 10514278 DOI: 10.1021/jm990208z] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As part of our continuing search for potential anticancer drug candidates in the 2-aryl-1,8-naphthyridin-4-one series, we have synthesized a series of substituted 2-thienyl-1, 8-naphthyridin-4-ones. Most compounds showed significant cytotoxic effects (log GI(50) < -4.0; log molar drug concentration required to cause 50% growth inhibition) against a variety of human tumor cell lines in the National Cancer Institute's in vitro screen, including cells derived from solid tumors such as non-small-cell lung, colon, central nervous system, melanoma, ovarian, prostate, and breast cancers. The most active compounds (31-33,40) demonstrated strong cytotoxic effects with ED(50) values in the micromolar or submicromolar range in most of the tumor cell lines. The most cytotoxic compounds inhibited tubulin polymerization at concentrations substoichiometric to the tubulin concentration. The most potent inhibitors of polymerization (40,42,43) had effects comparable to those of the potent antimitotic natural products podophyllotoxin and combretastatin A-4 and to that of NSC 664171, a particularly potent, structurally related analogue. Only compound 40 was a potent inhibitor of the binding of radiolabeled colchicine to tubulin, and it was both the most cytotoxic agent and the most effective inhibitor of polymerization among the newly synthesized compounds.
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Xu XM, Zhang SX, Li H, Aebischer P, Bunge MB. Regrowth of axons into the distal spinal cord through a Schwann-cell-seeded mini-channel implanted into hemisected adult rat spinal cord. Eur J Neurosci 1999; 11:1723-40. [PMID: 10215926 DOI: 10.1046/j.1460-9568.1999.00591.x] [Citation(s) in RCA: 209] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Schwann cells (SCs) have been shown to be a key element in promoting axonal regeneration after being grafted into the central nervous system (CNS). In the present study, SC-supported axonal regrowth was tested in an adult rat spinal cord implantation model. This model is characterized by a right spinal cord hemisection at the eighth thoracic segment, implantation of a SC-containing mini-channel and restoration of cerebrospinal fluid circulation by suturing the dura. We demonstrate that a tissue cable containing grafted SCs formed an effective bridge between the two stumps of the hemicord 1 month after transplantation. Approximately 10 000 myelinated and unmyelinated axons (1 : 9) per cable were found at its midpoint. In addition to propriospinal axons and axons of peripheral nervous system (PNS) origin, axons from as many as 19 brainstem regions also grew into the graft without additional treatments. Most significantly, some regenerating axons in the SC grafts were able to penetrate through the distal graft-host interface to re-enter the host environment, as demonstrated by anterograde axonal labelling. These axons coursed toward, and then entered the grey matter where terminal bouton-like structures were observed. In channels containing no SCs, limited axonal growth was seen within the graft and no axons penetrated the distal interface. These findings further support the notion that SCs are strong promotors of axonal regeneration and that the mini-channel model may be appropriate for further investigation of axonal re-entry, synaptic reconnection and functional recovery following spinal cord injury.
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Fukushima M, Takeda J, Fukamiya N, Okano M, Tagahara K, Zhang SX, Zhang DC, Lee KH. A new taxoid, 19-acetoxytaxagifine, from Taxus chinensis. JOURNAL OF NATURAL PRODUCTS 1999; 62:140-2. [PMID: 9917302 DOI: 10.1021/np980202x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A new taxane diterpene, 19-acetoxytaxagifine (1), was isolated from an ethanol extract of the aerial parts of Taxus chinensis. Its structure was determined on the basis of spectral evidence.
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Chen DF, Zhang SX, Wang HK, Zhang SY, Sun QZ, Cosentino LM, Lee KH. Novel anti-HIV lancilactone C and related triterpenes from Kadsura lancilimba. JOURNAL OF NATURAL PRODUCTS 1999; 62:94-7. [PMID: 9917290 DOI: 10.1021/np980291d] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Three new triterpene lactones, lancilactones A (1), B (2), and C (3), together with the known kadsulactone A (4), were isolated from the stems and roots of Kadsura lancilimba. Their structures and stereochemistries were determined primarily from mass and NMR spectral data. Compound 3 inhibited HIV replication with an EC50 value of 1.4 microg/mL and a therapeutic index of greater than 71.4.
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Ashford JW, Soultanian NS, Zhang SX, Geddes JW. Neuropil threads are collinear with MAP2 immunostaining in neuronal dendrites of Alzheimer brain. J Neuropathol Exp Neurol 1998; 57:972-8. [PMID: 9786247 DOI: 10.1097/00005072-199810000-00009] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Alzheimer disease (AD) neuropathology includes neuropil threads (NTs) and neurofibrillary tangles (NFTs). In tangle-bearing neurons, the normal cytoskeleton is severely disrupted and replaced with paired helical filament (PHF) aggregates of aberrantly phosphorylated microtubule-associated protein tau. In this study, double-label immunocytochemistry was used to clarify the relationship between the appearance of neurofibrillary pathology (NTs and NFTs) and the loss of normal cytoskeletal components, such as microtubule-associated protein 2 (MAP2) in 13 AD cases and 6 nondemented elderly control individuals. Brain areas examined included neocortex (cingulate, motor, and inferior parietal cortices), hippocampus, and entorhinal cortex. In mildly affected neurons, PHF-1 immunostained NTs were found in dendrites, frequently at dendritic branch points, and were adjacent to MAP2 immunostaining. In more severely affected neurons, the PHF-1 immunoreactivity occupied distinct dendritic segments and appeared to displace MAP2. Interspersed MAP2 immunopositive dendritic segments were often beaded in appearance. In all instances where dendrites with NTs could be traced back to the soma, the soma also contained PHF-1 immunostained fibrils in various stages of NFT formation. The results suggest that PHFs gradually displace normal microtubules in dendrites, and cause degeneration of dendritic segments between NTs.
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Smirnova IV, Zhang SX, Citron BA, Arnold PM, Festoff BW. Thrombin is an extracellular signal that activates intracellular death protease pathways inducing apoptosis in model motor neurons. JOURNAL OF NEUROBIOLOGY 1998; 36:64-80. [PMID: 9658339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Apoptosis, often also termed "programmed cell death", occurs in normal development in the brain and spinal cord. Important to concepts of disease and potential intervention is the exciting finding that apoptosis is also found after neurotrauma and in a number of neurodegenerative diseases. Although the precise mechanism of neuronal cell loss remains unknown, much emphasis has been placed recently on the activation of cell death protease cascades within the cell. How these cascades may be activated, especially from extracellular influences, is currently poorly understood. Thrombin, the multifunctional coagulation protease, is an early phase modulator at sites of tissue injury and has been shown to induce cell death in neurons by an apoptotic mechanism by activating its receptor, PAR-1. Using a model motor neuronal cell line, NSC19, which we have shown undergoes apoptosis after treatment with classic apoptosis inducers such as the topoisomerase inhibitors camptothecin and etoposide, we unambiguously found that nanomolar thrombin induced characteristic signs of apoptosis. Strikingly, endonucleolysis was accompanied by an increase in caspase-3-like activity in cellular extracts, which correlated with both detection of caspase-induced signature cleavage of the cortical cytoskeleton component nonerythroid spectrin (alpha-fodrin) and identification of increased accessibility of a caspase cleavage domain, using an antibody (Ab127) made against a synthetic peptide KGDEVD. Demonstrating that thrombin activation of death proteases was linked to cell death, we were able to inhibit thrombin-induced apoptosis by using a caspase family inhibitor, benzyloxycarbonyl-Asp-(oMe)-fluoromethyl ketone (Boc-D-FMK). These novel results demonstrate that thrombin serves as an extracellular "death signal" to activate intracellular protease pathways. These pathways lead to apoptotic cell death and can be modulated by inhibiting caspase activity downstream to PAR-1.
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Xi YZ, Zhang ZX, Zhang SX, Kong FH, Li XS, Tang PH, Wei W, Jin L, Chen XG. [The diversity of human hematopoietic stem/progenitor cells: IX. Cell-cycles kinetics related macromolecules DNA, RNA and protein contents in CD34+ hematopoietic cells of human bone marrow]. SHI YAN SHENG WU XUE BAO 1998; 31:129-35. [PMID: 12014141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
DNA, RNA and PRO comprise the bulk of macromolecules in cells, which have been proven to play an important role in regulating cell cycle transverse capacity, cell division, growth, and size. Simultaneous analysis of these moieties could provide more comprehensive and accurate information on cell cycle kinetics. In this study, DNA, RNA and PRO contents related to cell cycle kinetics in CD34+ hematopoietic cells of human bone marrow were measured to understanding the cell cycle kinetic features in CD34+ hematopoietic cells. For this reason, CIMS-100 immunomagnetic isolator, a novel isolation system, was used to enrich efficiently CD34+ hematopoietic cells from human bone marrow. The purity of enriched CD34+ hematopoietic cells determined by both FACS and APAAP staining is ranging from 90%-95%. Cellular DNA, RNA and PRO were stained with fluorochromes propidium iodide, pyronin Y and fluorescein isothiocyante respectively The fluorescence intensities reflecting the DNA, RNA and PRO content of individual cell were analyzed in FACS can by different excitation wavelengthes. DNA, RNA and PRO contents in CD34+ hematopoietic cells were far lower than these of bone marrow mononuclear cells, only being 34 +/- 3% (DNA), 48 +/- 21% (RNA) and 62 +/- 14% (PRO) of BMMNCs respectively. Collectively, these data combined with previous results from both ours and others indicated that CD34+ hematopoietic cells are indeed an unique cell population, not only in reconstitute of hematopoietic and immunological functions, but also in cell cycle kinetics. This is, to our knowledge, the first detailed report on the analysis of DNA, RNA and PRO contents related to cell cycle kinetics in CD34+ hematopoietic cells. And the results provide more direct evidence that the majority of CD34+ hematopoietic cells are in resting state.
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Zhang SX, Bentel JM, Ricciardelli C, Horsfall DJ, Haagensen DE, Marshall VR, Tilley WD. Immunolocalization of apolipoprotein D, androgen receptor and prostate specific antigen in early stage prostate cancers. J Urol 1998; 159:548-54. [PMID: 9649289 DOI: 10.1016/s0022-5347(01)63981-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE To determine the cellular distribution and levels of immunohistochemical staining for apolipoprotein D (Apo-D), prostate specific antigen (PSA) and androgen receptor (AR) in early stage prostate cancers. MATERIALS AND METHODS Cellular distribution of Apo-D, PSA and AR in 30 stage A/B prostate cancers and in non-malignant glandular tissue contained in the same sections was detected immunohistochemically, and staining was evaluated by computerized video image analysis. RESULTS Staining for Apo-D (percentage positive cellular area) was significantly increased in tumor cells of early stage prostate cancers compared with non-malignant glandular tissue. PSA and AR were present at high levels in both early stage prostate tumors and non-malignant prostate. CONCLUSIONS Malignant transformation in the prostate is associated with increased cellular levels of Apo-D.
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Smirnova IV, Citron BA, Arnold PM, Zhang SX, Festoff BW. Characterization of apoptosis in a motor neuron cell line. Spine (Phila Pa 1976) 1998; 23:151-8. [PMID: 9474719 DOI: 10.1097/00007632-199801150-00001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
STUDY DESIGN Serum withdrawal was introduced to a spinal cord motor neuron cell line to investigate the mode of cell death. OBJECTIVES To characterize the death of motor neurons in culture, to gain insight into mechanisms that could be important in spinal cord diseases. SUMMARY OF BACKGROUND DATA Normal reduction of cell number during central nervous system development is brought about by programmed cell death. These same apoptotic processes probably play a role in a variety of central nervous system disorders, including traumatic injury. Although certain proteolytic processes are involved, the molecular details involved in the apoptotic induction have not been fully elucidated. METHODS To identify apoptosis, several criteria were used, including analysis of chromatin condensation with DNA-specific stains (propidium iodide and Hoechst 33342); in situ end-labeling of DNA fragments in apoptotic nuclei with terminal deoxynucleotidyl transferase; fragmentation of DNA separated on agarose gel electrophoresis; and cleavage of a characteristic substrate for apoptotic proteases, alpha-fodrin, into signature cleavage fragments. RESULTS The NSC19 cell line exhibited motor neuron characteristics morphologically, with typical cellular structure, and biochemically, by synthesizing choline acetyl transferase. Under various treatments including serum withdrawal (loss of trophic factors), cell loss occurred through an apoptotic cell death pathway. CONCLUSIONS A murine motor neuron cell line, NSC19, has been used to investigate apoptosis in this in vitro system. Cell death occurs by apoptosis, suggesting that this cell line may provide a useful model for studying apoptotic mechanisms in spinal cord degeneration and injury.
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Shiue CY, Shiue GG, Zhang SX, Wilder S, Greenberg JH, Benard F, Wortman JA, Alavi AA. N-(N-benzylpiperidin-4-yl)-2-[18F]fluorobenzamide: a potential ligand for PET imaging of sigma receptors. Nucl Med Biol 1997; 24:671-6. [PMID: 9352539 DOI: 10.1016/s0969-8051(97)00097-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Four nitro- and fluorobenzamides (1-4) have been synthesized in good yields from nitro- and fluoro-substituted benzoyl chloride with 4-amino-1-benzylpiperidine. In vitro studies showed that these compounds have high affinities to sigma receptors. N-(N-Benzylpiperidin-4-yl)-2-fluorobenzamide (3), in particular, bound to sigma receptors with high affinity (Ki = 3.4 nM, guinea pig brain membranes) and high selectivity (sigma-2/sigma-1 = 120). It was, therefore, labeled with 18F and evaluated as a sigma receptor radioligand. N-(N-Benzylpiperidin-4-yl)-2-[18F]fluorobenzamide (3a) was synthesized in one step by nucleophile substitution of the 2-nitro precursor (1) with [18F]fluoride in DMSO at 140 degrees C for 20 min followed by purification with HPLC in 4-10% yield (decay corrected). The synthesis time was 90 min and the specific activity was 0.4-1.0 Ci/mumol. Tissue distribution in mice revealed that the uptakes of 3a in the brain, heart, liver, lungs, spleen, kidneys and small intestine were high, and the radioactivity in these organs remained constant from 60 to 120 min post-injection. The radioactivity in the bone did not significantly increase, suggesting in vivo defluorination may not be the major route of metabolism of 3a in mice. Blocking studies with haloperidol in rats indicated that the uptake of compound 3a in the rat brain was selective to haloperidol-sensitive sigma sites. These results suggest that compound 3a is a potent sigma receptor radioligand and may be a potential ligand for PET imaging of sigma receptors in humans.
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Xi YZ, Zhang ZX, Zhang SX, Kong FH, Tang PX, Wei W. [The diversity of human hematopoietic stem/progenitor cells: VIII. Sterological features of CD 34+ hematopoietic cells isolated from human bone marrow]. SHI YAN SHENG WU XUE BAO 1997; 30:273-83. [PMID: 11039022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Human CD 34+ hematopoietic cells, a distinctive cell population containing hematopoietic stem/progenitor cells, have the capability to highly self-renewal, differentiation into all lineages of committed progenitor cells and reconstitution of both long-term hematopoiesis and immune functions after transplantation. In our previous study, the morphological, ultrastructural and cytochemical features concerning CD 34+ hematopoietic cells obtained by a two-step isolated systems of CIMS-100/FACS 440 with 100% purity were depicted. Based on these observations on CD 34+ hematopoietic cells under light microscope, SEM and TEM, we recently analyze the sterological features of CD 34+ hematopoietic cells with the aid of Quantimet 970 automatic image analyser so that the three-dimension structures regarding CD 34+ hematopoietic cells could be further made clear. By a series of measures including image scan-->modulus transform-->shadow correction-->image store-->statistical analysis, some morphometric parameters of CD 34+ hematopoietic cells were obtained as the followings: diametrs 3.490-6.741 microns, perimeters 11.776-26.240 microns, surface area 9.565-35.686 microns2, form factors 1.048-1.840, nucleus-plasma ratio 0.55-0.72, mean light density 0.17675-0.65100, integral light density 2717.217-46661.000. These morphometric data combined with our previous results from morphology, ultrastructure and functional subsets of CD 34+ hematopoietic cells strongly demonstrate that CD 34+ hematopoietic cells are really a heterogenous population. The possible reasons causing heterogeneous are close associated with either different functional subsets or differentiation lineages. To our knowledge, this is the first identification of sterological features of CD 34+ hematopoietic cells.
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