451
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Zeng L, Gu ZM, Chang CJ, Wood KV, McLaughlin JL. Meliavolkenin, a new bioactive triterpenoid from Melia volkensii (Meliaceae). Bioorg Med Chem 1995; 3:383-90. [PMID: 8581421 DOI: 10.1016/0968-0896(95)00034-e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Meliavolkenin, a new triterpene with an apotirucallane skeleton, has been isolated from the root bark of Melia volkensii (Meliaceae) by bioactivity-directed fractionation using the brine shrimp lethality test. The structure has been elucidated using spectral and chemical data. The relative stereochemistries were determined by reduction and acetonide derivations, and the ring conformations were analyzed using the results of NOESY experiments. Meliavolkenin was bioactive in the brine shrimp lethality test and gave moderate cytotoxicities against three human solid tumor lines.
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452
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Savage A, Zeng L, Houslay MD. A role for protein kinase C-mediated phosphorylation in eliciting glucagon desensitization in rat hepatocytes. Biochem J 1995; 307 ( Pt 1):281-5. [PMID: 7536413 PMCID: PMC1136774 DOI: 10.1042/bj3070281] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An immobilized hepatocyte preparation was used to show that both vasopressin and glucagon could desensitize the ability of glucagon to increase intracellular cyclic AMP concentrations. This process was not dependent on any influx of extracellular Ca2+ and was not mediated by any rise in the intracellular level of Ca2+. The protein kinase C-selective inhibitors chelerythrine, staurosporine and calphostin C acted as potent inhibitors of the desensitization process but with various degrees of selectivity regarding their ability to inhibit the desensitizing actions of glucagon and vasopressin. The protein phosphatase inhibitor okadaic acid was just as potent as vasopressin and glucagon in causing desensitization. Treatment of hepatocyte membranes with alkaline phosphatase restored to near control levels the ability of glucagon to stimulate adenylate cyclase activity in membranes from both glucagon- and vasopressin-treated (desensitized) hepatocytes. It is suggested that the desensitization of glucagon-stimulated adenylate cyclase activity involves a reversible phosphorylation reaction with the likely target being the glucagon receptor itself.
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453
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Zeng L, Godeny EK, Methven SL, Brinton MA. Analysis of simian hemorrhagic fever virus (SHFV) subgenomic RNAs, junction sequences, and 5' leader. Virology 1995; 207:543-8. [PMID: 7886957 DOI: 10.1006/viro.1995.1114] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Full-length simian hemorrhagic fever virus (SHFV) genome RNA (about 15 kb in length) and six subgenomic RNAs, ranging in size from 0.65 to 4.7 kb, were detected by Northern blot hybridization in MA104 cytoplasmic extracts with a 3' genomic antisense probe. The 5' regions of the two smallest subgenomic RNAs (RNAs 6 and 7) were cloned and sequenced. Sequence analysis indicated that these two RNAs contained a common 5' leader sequence joined to the subgenomic RNA bodies via a highly conserved junction sequence; the junction sequence of RNA 7 was 5'-TTAACC-3', while that of RNA 6 was 5'-TCAACC-3'. The complete 5' leader sequence (208 nt) was obtained from genomic RNA. The genomic 5' junction sequence is identical to that of RNA 7. Northern blot hybridization with an antisense 5' leader probe confirmed the presence of the complete leader sequence in all six species of subgenomic RNA. In its virion morphology, genome size, gene order, and replication strategy, SHFV is most similar to viruses such as equine arteritis virus, lactate dehydrogenase-elevating virus, and Lelystad virus/porcine respiratory and reproductive syndrome virus.
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454
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Hou C, Zhang X, Fang Q, Shou T, Zeng L, Yan M, Zhou Y, Hu B, Li P. The analysis of disparity evoked potentials by a new form of static random-dot stereograms. YAN KE XUE BAO = EYE SCIENCE 1995; 11:48-52. [PMID: 8575607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE A new form of static random-dot stereograms free of monocular clues was designed as stimulus to elicit disparity evoked potentials. METHODS Disparity evoked potentials were recorded in 40 stereo-normal subjects. The stimulator was a white-black static random-dot stereograms generated by a computer and had no monocular clues. Every subject was tested in disparity stimulus, zero disparity stimulus, monocular stimulus and wearing prism condition. RESULTS A characteristic wide positive wave at about 250 ms was consistently recorded in disparity stimulus, which may be regarded as evidence of the presence of stereopsis. In contrast, recordings for zero disparity stimulus, monocular vision, stimulus and wearing prism condition all demonstrated a markedly difference from recording for disparity stimulus.
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455
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Goetzl EJ, An S, Zeng L. Specific suppression by prostaglandin E2 of activation-induced apoptosis of human CD4+CD8+ T lymphoblasts. THE JOURNAL OF IMMUNOLOGY 1995. [DOI: 10.4049/jimmunol.154.3.1041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
Receptors (Rs) for prostaglandin E2 (PGE2) of the EP2 subtype are expressed at high levels in rodent and human thymuses, with preferential localization on immature thymocytes. Human cultured lymphoblasts of the Tsup-1 line express CD4 and CD8 but only a low level of CD3, typical of immature thymocytes, and bear EP2-type Rs for PGE2 that were identified by binding of [3H]PGE2 and Ab to recombinant EP2Rs, and by cAMP responses to PGE2. PGE2 protected Tsup-1 cells from apoptosis initiated by diverse stimuli, including mitogenic lectins and anti-Fas or anti-CD3 plus anti-CD28 Abs, but not ionomycin, as assessed by suppression of both fragmentation of [3H]thymidine-labeled DNA and appearance of free 3'-OH ends of cleaved DNA. An EP2R-selective synthetic agonist also significantly suppressed lectin-induced apoptosis of Tsup-1 cells. Phosphodiesterase inhibition synergistically enhanced PGE2-induced increases in cAMP and decreases in apoptosis in parallel, which suggests that the EP2R-specific protective effect of PGE2 is mediated predominantly by cAMP suppression of apoptosis. Dibutyrylcyclic AMP alone protected Tsup-1 cells against lectin-induced apoptosis, but the maximal effect was less than that for PGE2. The thromboxane A2 mimetic U46619 initiated apoptosis of Tsup-1 cells that was suppressed significantly by PGE2. Immune negative selection of immature thymocytes thus may be regulated by opposing effects of endogenous eicosanoids that include destruction by thromboxane A2 and protection by PGE2.
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456
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Zeng L, Li X, Su J, Fu X, Schmitz FJ. A new cytotoxic dihydroxy sterol from the soft coral Alcyonium patagonicum. JOURNAL OF NATURAL PRODUCTS 1995; 58:296-298. [PMID: 7769395 DOI: 10.1021/np50116a025] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A new sterol, 24-methylenecholest-4-ene-3 beta,6 beta-diol [1] was isolated from the soft coral Alcyonium patagonicum collected from the South China Sea. Its structure was determined by spectral analysis. Compound 1 was cytotoxic against the P-388 cell line with an IC50 value of 1 microgram/ml.
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457
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Yang Y, Zeng L, Li M, Zhou J. Diarrhoea in piglets and monkeys experimentally infected with Balantidium coli isolated from human faeces. THE JOURNAL OF TROPICAL MEDICINE AND HYGIENE 1995; 98:69-72. [PMID: 7861483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Ten piglets and four monkeys free from Balantidium were dosed with human faecal homogenate which contained 1.2 x 10(4)-4.8 x 10(4) B. coli cysts. The infection resulted in severe diarrhoea in piglets 1-6 and hydrocortisone-treated monkeys 1-2, moderate diarrhoea in piglets 7-10 and a subclinical infection in monkeys 3-4. In piglets 1-3 and monkeys 1-2, heavy infection of the intestinal mucosa extended from the terminal ileum to the rectum and the mucosa was severely damaged. In piglets 4-10, infection was heavy in the large intestine with moderate mucosal damage.
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458
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Goetzl EJ, An S, Zeng L. Specific suppression by prostaglandin E2 of activation-induced apoptosis of human CD4+CD8+ T lymphoblasts. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1995; 154:1041-7. [PMID: 7822781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Receptors (Rs) for prostaglandin E2 (PGE2) of the EP2 subtype are expressed at high levels in rodent and human thymuses, with preferential localization on immature thymocytes. Human cultured lymphoblasts of the Tsup-1 line express CD4 and CD8 but only a low level of CD3, typical of immature thymocytes, and bear EP2-type Rs for PGE2 that were identified by binding of [3H]PGE2 and Ab to recombinant EP2Rs, and by cAMP responses to PGE2. PGE2 protected Tsup-1 cells from apoptosis initiated by diverse stimuli, including mitogenic lectins and anti-Fas or anti-CD3 plus anti-CD28 Abs, but not ionomycin, as assessed by suppression of both fragmentation of [3H]thymidine-labeled DNA and appearance of free 3'-OH ends of cleaved DNA. An EP2R-selective synthetic agonist also significantly suppressed lectin-induced apoptosis of Tsup-1 cells. Phosphodiesterase inhibition synergistically enhanced PGE2-induced increases in cAMP and decreases in apoptosis in parallel, which suggests that the EP2R-specific protective effect of PGE2 is mediated predominantly by cAMP suppression of apoptosis. Dibutyrylcyclic AMP alone protected Tsup-1 cells against lectin-induced apoptosis, but the maximal effect was less than that for PGE2. The thromboxane A2 mimetic U46619 initiated apoptosis of Tsup-1 cells that was suppressed significantly by PGE2. Immune negative selection of immature thymocytes thus may be regulated by opposing effects of endogenous eicosanoids that include destruction by thromboxane A2 and protection by PGE2.
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459
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Eveno E, Quilliet X, Chevallier-Lagente O, Daya-Grosjean L, Stary A, Zeng L, Benoit A, Savini E, Ciarrocchi G, Kannouche P. Stable SV40-transformation and characterisation of some DNA repair properties of fibroblasts from a trichothiodystrophy patient. Biochimie 1995; 77:906-12. [PMID: 8824772 DOI: 10.1016/0300-9084(95)90011-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To characterize nucleotide excision repair properties of cells from trichothiodystrophy (TTD) patients genetically-related to the xeroderma pigmentosum (XP) group D, TTD skin fibroblasts from two unrelated patients (TTD1VI and TTD2VI) belonging to the TTD/XPD group were transformed with a plasmid containing SV40 large T antigen-coding sequences and some DNA repair properties, such as unscheduled DNA synthesis (UDS), UV-survival, in vitro repair synthesis of cell extracts and reactivation of UV-irradiated reporter plasmid were studied. Results showed that: a) both untransformed and transformed TTD cells present a reduced UV-survival, compared to wild-type cells, but at significantly less reduced levels than XP-D cells; b) reduced repair activities were detected in both TTD and XP-D transformed cells by using in vitro cell free extract repair and reactivation of UV-irradiated plasmid procedures, and these relative reduced extents correlated with respective UV-survival; c) surprisingly, near wild-type UDS levels were detected in TTD2VILas transformed cells at different passages after the crisis, suggesting a phenotypic reversion of this transformed cell line; d) fluoro-cytometric analysis of TTD2VILas cells revealed a strong increase of a cell population containing a DNA amount more than twice as high than that of untransformed cells; finally, e) when UDS data were normalized to the DNA content in TTD2VILas cells, it appeared that the repair efficiency was only slightly higher than in untransformed cells. This implies that in transformed cells DNA repair properties should be evaluated, taking into account additional parameters. We obtained an immortalized TTD cell line which maintains DNA repair properties similar to those of parental untransformed cells and may be used to characterize the TTD defect at genetic, molecular and biochemical levels.
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460
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An S, Yang J, So SW, Zeng L, Goetzl EJ. Isoforms of the EP3 subtype of human prostaglandin E2 receptor transduce both intracellular calcium and cAMP signals. Biochemistry 1994; 33:14496-502. [PMID: 7981210 DOI: 10.1021/bi00252a016] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The EP3 subtype of prostaglandin E2 receptor transduces diverse physiological responses in mammalian tissues through signaling pathways coupled to heterotrimeric G proteins. Distinct cDNA clones encoding five isoforms of the EP3 receptor were isolated from a human uterus cDNA library. The human EP3 receptor isoforms designated hEP3-I, I', II, III, and IV are derived from alternative RNA splicing and differ only in the distal sequences of their carboxyl-terminal cytoplasmic tails. The unique cytoplasmic tails consist of 31 amino acids for isoforms I and I', 29 for II, 6 for III, and 15 for IV. When stably expressed in CHO cell transfectants, all isoforms exhibited similar EP3-specific binding of [3H]-PGE2 and PGE2 analogs. The EP3-selective agonist M&B 28767 both decreased the intracellular cAMP concentration ([cAMP]i) and increased the intracellular concentration of calcium ([Ca2+]i) with quantitative differences among different isoforms, but none mediated an increase in [cAMP]i. Pertussis toxin treatment completely blocked the decrease in [cAMP]i, but not the increase in [Ca2+]i evoked by M&B 28767. PGE2-induced desensitization of [3H]PGE2 binding by isoforms III and IV was rapid and transient, whereas that by isoform II was slow and persistent. Reverse transcription-PCR amplification of EP3 receptor messages in human kidney and uterine tissue RNA detected expression of all isoforms with different abundancies. The dual signal transduction pathways and distinctive tissue distribution of isoforms of the EP3 receptor are consistent with its mediation of diverse functions of PGE2.
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461
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Guo L, Ma Q, Chen Y, Zeng L. [Studies on MDA and MDA/MDAa in patients with retinitis pigmentosa]. YAN KE XUE BAO = EYE SCIENCE 1994; 10:224-6, 196. [PMID: 7774696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
With fluorimetry, the concentration of malondialdehyde (MDA) and the ratio of MDA before and after the blood platelets activated (MDA/MDAa) were determined in patients with retinitis pigmentosa (RP). The results showed the above two parameters were statistically higher than those of the normal controls, which indicated the superoxidation metabolism increased and the blood was in a state of hypercoagulation in RP patients. The reasons for the results and their roles in RP disease were discussed. Treatments with anti-lipid, and anti-coagulation drugs combined with Chinese medicines were suggested.
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462
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Goetzl EJ, Yang J, Xia M, Zeng L, So SW, An S. Diverse mechanisms of specificity of human receptors for eicosanoids. Ann N Y Acad Sci 1994; 744:146-54. [PMID: 7825835 DOI: 10.1111/j.1749-6632.1994.tb52731.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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463
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Monti G, Jaurand MC, Monnet I, Chretien P, Saint-Etienne L, Zeng L, Portier A, Devillier P, Galanaud P, Bignon J. Intrapleural production of interleukin 6 during mesothelioma and its modulation by gamma-interferon treatment. Cancer Res 1994; 54:4419-23. [PMID: 8044791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In vivo production of monokines was analyzed in 17 human malignant pleural mesotheliomas. High concentrations of interleukin 6 (IL-6) were detected in pleural effusions, contrasting with low levels of IL-1 beta and tumor necrosis factor alpha. This production arose from malignant cells, as shown by immunochemical analysis of pleural cells and by production of IL-6 by mesothelial cell lines. Intrapleural administration of recombinant human gamma-interferon to six patients led to a marked decrease in intrapleural IL-6 concentrations in all cases. This treatment was associated with in situ activation of macrophages and cytotoxic T-lymphocytes, as indicated by increased intrapleural neopterin and soluble CD8 concentrations. In vitro gamma-interferon had no effect on the production of IL-6 by mesothelial cell lines but decreased the growth of 3 of 6 mesothelioma cell lines. These results indicate that systemic manifestations of malignant mesothelioma, including fever, cachexia, and thrombocytosis may be related to the production of IL-6 by malignant cells, and that local gamma-interferon infusion may reduce this production by stimulating antitumoral immunity and/or by directly decreasing the proliferation of malignant cells.
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464
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Zeng L, Worseg A, Albrecht G, Grisold W, Hopf R, Redl H, Schlag G. A noninvasive functional evaluation following peripheral nerve repair with electromyography in a rat model. Plast Reconstr Surg 1994; 94:146-51. [PMID: 8016227 DOI: 10.1097/00006534-199407000-00016] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A new bipolar surface electrode array was designed and constructed for a noninvasive "closed" functional evaluation with electromyography following sciatic nerve transection in a rat model. This "closed" method was compared with a conventional one-shot "open" measurement. Nerve conduction velocity and distal latency were calculated. Data obtained from the recordings from different animals as well as from the same animal at different points in time yielded excellent reproducibilities. There is no difference in the mean values whether nerve conduction velocity and distal latency are obtained by "closed" or "open" measurements. Correlation was significant (p < 0.01; rNCV = 0.77, rDL = 0.63) between these two methods. The results lead to the conclusion that the noninvasive functional evaluation with the parameters of nerve conduction velocity and distal latency introduced in the present study could be employed as a reliable method for serial functional evaluations following nerve transection in a long-term study in a rat model.
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465
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Zeng L, Fleury-Feith J, Monnet I, Boutin C, Bignon J, Jaurand MC. Immunocytochemical characterization of cell lines from human malignant mesothelioma: characterization of human mesothelioma cell lines by immunocytochemistry with a panel of monoclonal antibodies. Hum Pathol 1994; 25:227-34. [PMID: 7512071 DOI: 10.1016/0046-8177(94)90192-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A panel of nine monoclonal antibodies was used to characterize human mesothelioma cell lines that we established from human malignant mesothelioma. The antigens detected were cytokeratin, vimentin, epithelial membrane antigen, carcinoembryonic antigen, Leu-M1 (CD15), desmin, factor VIII-related antigen (von Willebrand factor antigen), OV632, and ME1, a specific monoclonal antibody directed against human malignant mesothelioma. The technique used was the alkaline phosphatase anti-alkaline phosphatase method. All 30 cell lines, either epithelial, sarcomatous, or mixed, showed strong reactivity with cytokeratin and vimentin antibodies. None of the cell lines demonstrated any reactivity with carcinoembryonic antigen, Leu-M1, or factor VIII antibodies; moreover, all of 22 cell lines studied were positive for ME1 antibody and 10 of 12 cell lines studied were positive for OV632. Some interesting features were noted: only two of the 30 cell lines presented a weak positive staining with epithelial membrane antigen, and nine of 19 cell lines tested demonstrated a cytoplasmic staining pattern with desmin antibody. These results show that established human mesothelioma cell lines still possess the immunocytochemical characteristics that are basically consistent with the immunohistochemical features described in tumor tissues of malignant mesothelioma. These characteristics can be used to identify the mesothelioma cells grown from human malignant mesothelioma. Hence, the mesothelioma cell lines will provide a useful tool for the investigation of the cell biology of the tumor and the mechanisms of mesothelial cell transformation, as well as the in vitro evaluation of the effects of some drugs in order to develop new therapies for malignant mesothelioma.
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466
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Zeng L, Gu ZM, Fang XP, McLaughlin JL. Kneglomeratanol, kneglomeratanones A and B, and related bioactive compounds from Knema glomerata. JOURNAL OF NATURAL PRODUCTS 1994; 57:376-381. [PMID: 8201311 DOI: 10.1021/np50105a007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
One new phenylalkyl phenol, kneglomeratanol [1], and two new acetophenones, kneglomeratanones A [2] and B [3], together with ten known compounds, 3-(12'-phenyldodecyl)-phenol [4], 3-(10'-phenyldecyl)-phenol [5], 5-pentadecylresorcinol [6], 5-(10'-phenyldecyl)-resorcinol [7], 5-(12'-phenyldodecyl)-resorcinol [8], 2,4-dihydroxy-6-(10'-phenyldecyl)-acetophenone [9], 2-hydroxy-6-(12'-phenyldodecyl)-benzoic acid [10], formononetin, biochanin A, and 8-O-methylretusin, have been isolated from the stem bark of Knema glomerata. Brine shrimp lethality was used for the activity-directed chromatographic fractionations. All of these compounds showed moderate but significant toxicities to three human tumor cell lines and inhibited the growth of crown gall tumors on discs of potato tubers.
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467
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Abstract
The sequence specificity of DnaK substrate binding has been studied using a peptide display library. Based on the amino acid patterns that appeared in this selection, short peptides were synthesized for direct measurements of DnaK affinity. The results show that peptides enriched in internal hydrophobic residues are preferential DnaK substrates, and negatively charged peptides have poor affinity. The isolated C-terminal domain of DnaK binds peptides. Peptide dissociation studies indicate that bound peptides are released from the C-terminal fragment and from DnaK at identical rates. ATP stimulates peptide dissociation from DnaK but not from the C-terminal fragment.
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468
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Zeng L, Buard A, Monnet I, Boutin C, Fleury J, Saint-Etienne L, Brochard P, Bignon J, Jaurand MC. In vitro effects of recombinant human interferon gamma on human mesothelioma cell lines. Int J Cancer 1993; 55:515-20. [PMID: 8375935 DOI: 10.1002/ijc.2910550331] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Malignant mesothelioma is a tumor arising from serous surfaces and often related to asbestos exposure. Malignant mesothelioma is resistant to various forms of therapy. Radiotherapy, surgery or chemotherapy only slightly improve prognosis. IFN-gamma produces complete or partial responses in stage-I patients with malignant mesothelioma. The in vitro biological effect of IFN-gamma on malignant mesothelioma cells remains poorly elucidated. In the present study, 32 well-characterized human mesothelioma cell lines (HMCL) were treated with r-hu IFN-gamma at 4 doses and cell growth was determined by a colorimetric method (MTT assay). Among the 32 HMCLs tested, II exhibited significant cell-growth inhibition; 16 were insensitive to r-hu IFN-gamma, and 5 were slightly inhibited. The sensitive cell lines were strongly inhibited by r-hu IFN-gamma. Our results show that HMCL exhibit a large range of responses to r-hu IFN-gamma, some of which can be compared with those obtained in vivo in humans.
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469
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470
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Su J, Zheng Y, Zeng L, Pordesimo EO, Schmitz FJ, Hossain MB, van der Helm D. Patagonicol: a diterpenoid from the Chinese soft coral Alcyonium patagonicum. JOURNAL OF NATURAL PRODUCTS 1993; 56:1601-1604. [PMID: 7902863 DOI: 10.1021/np50099a023] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Patagonicol [1], a diterpenoid with a eunicellin skeleton, was isolated from the soft coral Alcyonium patagonicum. The structure of 1 was determined by X-ray diffraction, and detailed 1H and 13C assignments were made via 1D and 2D nmr experiments.
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471
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Schwarz N, Redl H, Zeng L, Schlag G, Dinges HP, Eschberger J. Early osteoinduction in rats is not altered by fibrin sealant. Clin Orthop Relat Res 1993:353-9. [PMID: 8393393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The angiogenic and fibrogenic activities of fibrin sealant (Tisseel) suggest that it could enhance osteoinductivity during the first days after implantation. To test this hypothesis, the osteoinductivity of sealed and unsealed bone matrix gelatin was tested by implantation into rat abdominal wall muscle pouches for two to ten days. A sponge of collagen with or without fibrin sealant was used for control. Alkaline phosphatase (ALPase) was employed to quantify osteoinduction, and myeloperoxidase (MPO) was used to determine the inflammatory reaction. Plain histologic analysis of bone matrix gelatin implants at Days 2, 4, and 10 did not demonstrate any significant differences between sealed and nonsealed implants. Histologic analysis at Day 21 confirmed the osteoinductivity of the implant. The combination of bone matrix gelatin and fibrin sealant induced an early significant increase in ALPase activity, which could be interpreted as early induction of histologically undetectable osteogenesis. A simultaneous increase in the level of MPO suggested that the bone matrix gelatin/fibrin sealant-induced ALPase reaction might be caused by an inflammatory process, but neutrophil counting did not correlate to the MPO data. Morphometry, however, seems to be insufficient to assay a heterogenous histologic distribution of singular cells. It is proposed that the ALP/MPO ratio may be used as an inflammation-independent marker of osteogenesis. This study does not support the notion of an osteoinductive potency of fibrin sealant per se; however, it is clear that fibrin sealant does not impair bone matrix gelatin-dependent osteoinduction.
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472
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Zeng L. [Squamous cell carcinoma associated antigen levels in monitoring the response to surgical treatment for patients with esophageal carcinoma]. ZHONGHUA YI XUE ZA ZHI 1993; 73:469-70, 510. [PMID: 8111645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The serum levels of the squamous cell carcinoma associated antigen (SCCAg) were measured in 50 patients with esophageal carcinoma by immunoradiometric assay before and after surgery. 32 patients were subjected to curative surgery, 15 palliative operation, 3 exploratory thoracotomy. After curative surgery, the elevated level dropped rapidly to normal within 72 hours. The SCCAg levels showed statistical differences. In patients having palliative operation, the SCCAg levels declined but usually remained above the normal range. After exploratory thoracotomy, the SCCAg levels usually increased. Because SCCAg responded well to the effects of surgery, it was considered to be a very useful tumor marker in monitoring the response to surgical treatment for patients with esophageal carcinoma.
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473
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Zeng L. [Clinical significance of serum SCC Ag in patients with squamous cell carcinoma of the lung]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1993; 31:143-5. [PMID: 8223022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To evaluate its clinical significance as a tumor marker, the serum level of squamous cell carcinoma associated antigen (SCC Ag) was studied by immunoradiometric assay in 59 patients with histologically proved lung cancer (32 squamous cell carcinomas, 23 adenocarcinomas and 4 small cell carcinomas). Carcinoembryonic antigen (CEA) was measured by radioimmunoassay simultaneously. The serum levels of SCC Ag and CEA were found above the normal range in 71.9% and 28.1% of squamous cell carcinomas, 26.1% and 34.8% of adenocarcinomas and 0% and 25% of small cell carcinomas respectively. In squamous cell carcinomas, the positive rate of SCC Ag increased with progression of clinical stage. With regard to the preoperative serum level dropped dramatically after surgery (P < 0.05). The change would be more outstanding after radical surgery (P < 0.001). The serum level of SCC Ag can be used to effectively monitor the course of disease, and could be used as an important item during the postoperative follow-up.
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474
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Zeng L, Xu F, Ma Q, Chen Y. [Hurler syndrome (a case report)]. YAN KE XUE BAO = EYE SCIENCE 1992; 8:189-92. [PMID: 1306502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A case of Hurler syndrome diagnosed by clinical and laboratory examination is reported. The patient's roentgenograms showed the dystrophies of bones, lace-shaped ribs, boat-shaped cranium, fishhook-shaped forefront protrusion of silla trucica. Corneal opacities and high ocular pressure were found in both eyes. VEP measurement suggested the defects of optic nerve. The authors emphasized that visual electric physiological examinations should be used to estimate the visual functions when the patient's refractive medium is opqaue. The differential diagnosis was also briefly discussed.
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475
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Guo X, Chen Y, Zeng L. Modern surgical treatment of congenital subluxated lenses. YAN KE XUE BAO = EYE SCIENCE 1992; 8:113-6. [PMID: 1303867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Traditional surgical management of subluxated lenses is usually associated with a high incidence of operative and postoperative complication and a poor visual outcome. We treated a series of 14 patients (26 eyes) whose visual acuity could not be improved with optical correction (phakic or aphakic) with modern microsurgery and automated suction-cutting devices. Preoperative visual acuity ranged from 0.05 to 0.3. Improvement in post-operative visual acuity was documented in all operated eyes, ranging from 0.4 to 1.0 during a follow-up period ranging from 6 to 59 months (medium 43 months). The only complication was a small accidental cut in the pupillary border in three eyes. Other complication did not occur.
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476
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Chen Y, Zeng L, Ma Q, Su W, Mao W. The study of G6PD in erythrocyte and lens in senile and presenile cataract. YAN KE XUE BAO = EYE SCIENCE 1992; 8:12-5, 33. [PMID: 1286674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The G6PD activity of erythrocytes in 113 male patients with senile and presenile cataract and 86 controls, and G6PD activity of lens in 30 patients with senile cataract and 42 controls were reported. The cataractous group had higher frequency of G6PD deficiency and lower average G6PD level in erythrocytes and lenses, but without statistical significance. The frequency of G6PD deficiency of erythrocytes in presenile cataractous group was higher than that of senile cataractous group but with no statistical significance too. However, the average G6PD level of erythrocytes in presenile cataractous group was lower than that of senile cataractous group and with statistical significance (P < 0.05). The G6PD activity of lenses only presenile in the cortex and have a positive correlation with that of erythrocytes. There was a case with deficiency of G6PD both of erythrocytes and cataractous lenses in both eyes. The results indicate that the deficiency of G6PD might be one of the cataractous pathogenetic factor for presenile cataract. Measurement of G6PD activity of erythrocytes among population might be of significance in finding the risk factor for cataract.
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477
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Guo X, Mao W, Chen Y, Ma Q, Zeng L, Luo T. [A clinical study and analysis of congenital lenticular dislocation (35 cases)]. YAN KE XUE BAO = EYE SCIENCE 1991; 7:185-9. [PMID: 1844074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Thirty-five cases of congenital lenticular dislocation seen in our Center since 1985 have been studied and analyzed clinically. By the survey of pedigrees and examination of these patients, including ocular, systemic, skeletal X-ray, psychocardiogram, and urinary sodium-nitroprusside test, 21 cases were diagnosed as Marfan's syndrome, 6 cases as simple ectopia lentis, 3 cases as Weill-Marchesani's syndrome, 4 cases as aniridia and 1 case as homecys tinuria. We found that the most significant ocular manifestation of congenital lenticular dislocation was reduction in visual acuity. The severity of visual disturbance varied with the types of dislocation and the visual deficiency was closely related to the intermediate-grade (II) dislocation of the lens. Examination of ERG showed normal function in most of the patients. From this, we believe that the major cause of visual reduction in congenital lenticular dislocation is lenticular myopia and astigmatism. There fore, early diagnosis and effective correction of vision should be emphasized to prevent the occurrence of amblyopia.
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478
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Li D, Ma Q, Chen Y, Zeng L. [Waardenburg syndrome]. YAN KE XUE BAO = EYE SCIENCE 1991; 7:196-8, 171. [PMID: 1844076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report a patient with Waardenburg syndrome. He suffers from congenital deafness and presents high broad nasal root, synophrys, iris heterochromia and fundus hypopigment. The dystopia canthus is absence. In his family pedigree analysis, we found that his second cousin has oculocutaneous albinism.
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479
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Tanaka Y, Zeng L, Shiraki H, Shida H, Tozawa H. Identification of a neutralization epitope on the envelope gp46 antigen of human T cell leukemia virus type I and induction of neutralizing antibody by peptide immunization. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1991; 147:354-60. [PMID: 1711082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have generated a number of mAb against various epitopes on the external envelope glycoprotein, gp46, of human T cell leukemia virus type I (HTLV-I) from a WKA rat immunized with a recombinant vaccinia virus containing the HTLV-I env gene. Among these mAb, one group of mAb, represented by a mAb designated LAT-27, could neutralize the infectivity of HTLV-I, as determined by a HTLV-I-mediated cell fusion inhibition assay. LAT-27 also interfered with transformation of normal T lymphocytes by HTLV-I in vitro. An antibody-binding assay using overlapping synthetic oligopeptides showed that LAT-27 bound specifically to 10-mer peptides that contained the gp46 amino acid sequence 191-196 (Leu-Pro-His-Ser-Asn-Leu). Antibodies from HTLV-I+ humans interfered with the binding of LAT-27 to gp46 Ag. Sera from rabbits immunized with a LAT-27-reactive peptide, 190-199, conjugated with OVA, but not sera from OVA-immunized rabbits, reacted with gp46 Ag and neutralized infectivity of HTLV-I. These results show that the HTLV-I neutralization epitope recognized by LAT-27 locates to the gp46 amino acids 191-196, and that immunization with a peptide containing the LAT-27 epitope can elicit an HTLV-I neutralizing antibody response.
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480
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Tanaka Y, Zeng L, Shiraki H, Shida H, Tozawa H. Identification of a neutralization epitope on the envelope gp46 antigen of human T cell leukemia virus type I and induction of neutralizing antibody by peptide immunization. THE JOURNAL OF IMMUNOLOGY 1991. [DOI: 10.4049/jimmunol.147.1.354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
We have generated a number of mAb against various epitopes on the external envelope glycoprotein, gp46, of human T cell leukemia virus type I (HTLV-I) from a WKA rat immunized with a recombinant vaccinia virus containing the HTLV-I env gene. Among these mAb, one group of mAb, represented by a mAb designated LAT-27, could neutralize the infectivity of HTLV-I, as determined by a HTLV-I-mediated cell fusion inhibition assay. LAT-27 also interfered with transformation of normal T lymphocytes by HTLV-I in vitro. An antibody-binding assay using overlapping synthetic oligopeptides showed that LAT-27 bound specifically to 10-mer peptides that contained the gp46 amino acid sequence 191-196 (Leu-Pro-His-Ser-Asn-Leu). Antibodies from HTLV-I+ humans interfered with the binding of LAT-27 to gp46 Ag. Sera from rabbits immunized with a LAT-27-reactive peptide, 190-199, conjugated with OVA, but not sera from OVA-immunized rabbits, reacted with gp46 Ag and neutralized infectivity of HTLV-I. These results show that the HTLV-I neutralization epitope recognized by LAT-27 locates to the gp46 amino acids 191-196, and that immunization with a peptide containing the LAT-27 epitope can elicit an HTLV-I neutralizing antibody response.
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481
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Li D, Mao W, Ma Q, Chen Y, Zeng L. [Galactose-1-phosphate uridyl transferase and congenital cataract]. YAN KE XUE BAO = EYE SCIENCE 1991; 7:67-9. [PMID: 1844060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The activity of red blood cells galactose-1-p-uridyl transferase (GPUT) was determined by the spectrophotofluorometric method. The average GPUT activity in 102 control subjects was 13. 34 +/- 2. 03u. There were no differences in the sexes and ages. The average GPUT activity in 108 patients with congenital cataract was 11.58 +/- 4. 03u and was lower than that of the controls (P < 0.01). The GPUT activity in 14 of the 108(12.96%)patients was all-3SD below the mean value of the controls (< 7.24u) and the range was from 4.02u to 7.13u with the mean value of 5. 93u being about 44.45% of the normal. The difference between the two groups was statistically significant (P < 0.001). The results indicated that some of the patients with congenital cataract were due to decrease in the GPUT activity. The patients with decrease GPUT activity were mainly suffering from cataracts and their systemic disease were mild.
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482
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Li H, Wu Z, Zheng X, Liu S, Zheng Z, Zeng L, Duanmu B, Ke F, Yan H, Qing Y. [Pathological observation of experimental asbestosis treated by hydroxy piperquin phosphate in dogs]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1991; 22:181-4. [PMID: 1786956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The paper presents experimental asbestosis treated with hydroxy piperquin phosphate (HPQP) in dogs. Results showed that the total cell number of bronchoalveolar lavage fluid, the viability of alveolar macrophages and the enzyme activities of lactate dehydrogenase, acid phosphatase and beta-glucuronidase of alveolar macrophages in treated dogs were higher than those in exposed dogs, asbestos fibers contents in the lungs and the mean scores of lung lesions in the treated dogs were markedly less than those in the exposed dogs. These findings support that HPQP may play a role in protecting alveolar macrophages from damage and inhibiting the progression of lung fibrosis, and that the clinical application of HPQP is somehow evidenced by this study.
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483
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Zeng L, Zhang RY, Wang D, Zhang ZL, Lou ZC. Glyyunnansapogenins G and H: Two New Pentacyclic Triterpenoids of the 18alphaH-Oleana-9(11),12-diene Type from Glycyrrhiza yunnanensis Roots. PLANTA MEDICA 1991; 57:165-8. [PMID: 17226143 DOI: 10.1055/s-2006-960057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Two new pentacyclic triterpenoid sapogenins of the 18alpha H-oleana-9(11),12-diene type named glyyunnansapogenins G and H were isolated from the roots of GLYCYRRHIZA YUNNANENSIS Cheng f. et L. K. Tai. Their structures were elucidated as 18alpha H-oleana-9(11),12-diene-3beta,21alpha,29-triol and 18alpha H-3beta,21alpha-dihydroxyoleana-9(11),12-dien-29-oic acid, respectively, by spectroscopic methods. This is the first report of the occurrence of the 18alpha H series of oleana-9(11),12-diene compounds in nature.
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484
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Li H, Zhen Z, Zeng X, Zeng L, Ke F, Yang H. [Small-airway lesions induced by inhalation of asbestos dust in dogs--pathological and aetiological studies]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1991; 22:46-50. [PMID: 1774036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper presents the pathological changes of the small airways of dogs inhaling asbestos dust in the workshop of Xin Kong Asbestos Mine for 1 to 3 years. Dogs of the experimental group showed that variable degrees of dust deposition and fibrous tissue reaction were found in all the three types of the small airways-respiratory bronchioles, alveolar ducts and membranous bronchioles of both lungs. The lesions in the lung increased with the duration of exposure. These changes in the canine small airways resulting from asbestos dust were very much similar to those of the humans. In addition, deposited dust collected from the workshop of the asbestos mine, and 50 dust particles selected randomly in foci were identified in situ by energy dispersive X-ray analysis. Findings demonstrated that the majority of the dust particles in the foci was principally mixed silicate dust. Among them asbestos dust predominated absolutely, and there were more amphiboles than chrysotiles. Therefore, it is concluded that the small airway lesions induced in the dogs are mainly due to mixed asbestos dust, and that there appears to exist a dose-response relationship.
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485
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Schwarz N, Schlag G, Thurnher M, Eschberger J, Zeng L. Decalcified and undecalcified cancellous bone block implants do not heal diaphyseal defects in dogs. Arch Orthop Trauma Surg 1991; 111:47-50. [PMID: 1772726 DOI: 10.1007/bf00390194] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
UNLABELLED In a previous study it has been shown that granulae of decalcified bone matrix do not induce bony healing of 8-week-old mid-diaphyseal defects in dogs. The aim of this study was to test whether osteoinduction combined with the osteoconductive mechanisms provided by the natural structure of cancellous bone blocks would yield better results. A 30-mm-long diaphyseal defect of the left ulna was created in eight adult mongrel dogs and the bone was stabilized with a plate. A Silastic spacer was inserted in the defect for 8 weeks, followed by implantation of frozen undecalcified or decalcified allogeneic cancellous bone blocks for 16 weeks. Healing was analyzed using morphologic methods. At 16 weeks after implantation all grafts had been resorbed. In the decalcified group one defect healed, while none in the other group did so. The implant material was bioassayed in nude rats for osteoinductivity, which was found to be low in decalcified matrix and not detectable in undecalcified bone. CONCLUSION Allogeneic cancellous bone blocks, demineralized or not, have no osteoinductive capacity and no osteoconductive function that promotes healing of mid-diaphyseal bone defects in dogs.
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486
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Mao W, Zeng L, Ma Q, Chen Y, Dai Z, Tang P, Guo X, Li D, Su W. [Primary study of iontophoresis of zinc ion in treatment of retinitis pigmentosa]. YAN KE XUE BAO = EYE SCIENCE 1990; 6:88-90. [PMID: 2289582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We report here the preliminary effects of zinc iontophoresis in treatment of 26 Rp patients who had decreased zinc serum level or abnormal ratio of serum copper to zinc. Through more than 20 to 30 times of therapy, the vision of 15.38% eyes increased more than "3 lines", 4% eyes increased more than 5 degrees in the visual field, 13.46% eyes improved in dark adaptation threshold (greater than 1.0), the visual functions of the rest eyes were slightly improved or unimproved. The fundus didn't change before & after treatment. There were no changes of ERG in 8 eyes of 4 cases. In addition, the advantages and disadvantages between Zn iontophoresis and Zn compound taken orally, the improvement of vision by direct electric current therapy, the relationship between the metabolism of Zn element and Vit A and influence of Zn over the mechanism of dark adaptation were also briefly discussed.
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487
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Zeng L, Zheng ZR, Li HY, Tan JS. [Pathological study of bronchio-alveolitis induced by xinkang short-fiber chrysotile asbestos in rats]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1989; 20:290-4. [PMID: 2625335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Eighty-four rats were exposed intratracheally to 25 mg of locally produced Xinkang short-fiber chrysotile asbestos (98% of the fibers are less than 5 microns in length). In 1 to 3 d after instillation, the pathological changes in rat lungs demonstrated that the affection was mainly acute bronchio-alveolitis characterized by acute inflammatory exudation and injuries of the small airways and alveolar structural units. The four main manifestations of alveolitis induced by the chrysotile asbestos were of the neutrophilic, serous, alveolar macrophages and granulomatous varieties. Three types of pulmonary fibrosis developed gradually from 7 to 90 d following the exposure to the asbestos, i.e. the intraluminal, murally incorporated, and interstitial fibrosis. Findings showed the complete process from the acute inflammatory exudation and the damage to lung tissue, with the following repair and proliferation of injuried lung tissue and organization of exudate, to the final fibrosis and destruction of the lung. The results suggested that the persistent and irreversible damage to the epithelial cells of respiratory bronchioles and pneumocytes, and denudation and destruction of the basement membrane played an important role in the development of pulmonary fibrosis by forming a channel for the inflammatory exudates and fibroblasts migrating into the bronchioalveolar spaces. Therefore, the experimental results have proved that Xinkang chrysotile asbestos fibers less than 5 microns in length certainly have a fibrogenic effect.
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488
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Zeng L, Zheng ZR, Zhang SQ. [Pathogenic effects of titanium dioxide dust on the lung of dogs--a histopathological and ultrastructural study]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1989; 20:88-91. [PMID: 2793152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Titanium dioxide (TiO2) dust has generally been regarded as a "nuisance dust" in experimental animals and men. In this experiment, 16 dogs were exposed intratracheally to TiO2 dust for 9-15 months. The scanning electron microscopy with energy dispersive analysis of X-ray (SEM-EDAX), performed to identify the elemental composition of dust particles used in the study and in the focal lesions of the lungs, showed that dust particles were nearly pure titanium. Dust in the lung deposited mainly in the respiratory bronchioles and adjacent alveoli, with many alveoli filled by compacted dust particles. The pulmonary responses consisted of slight alveolitis, centrilobular emphysema, focal collapse of alveoli, and fibroblast hyperplasia with a few collagen fibres surrounding some of the TiO2-dust foci. Electron microscopically, many alveolar macrophages with intact nuclei contained a great amount of dust particles in their lysosomes, and in the dust foci, most of type I pneumocytes disappeared and type I pneumocytes showed hyperplasia. The alveolar subepithelial basement membrane were markedly thickened and bundles of collagen fibres were formed in the interstice. These findings suggest that TiO2 dust is one of the sorts which probably induce mild lung fibrosis in case a large amount is deposited in the lung tissue.
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489
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Bai X, Zeng L. Anisotropic broadening of the linewidth in the EPR spectra of Cr3+ ions in various doped yttrium aluminum garnet single crystals. PHYSICAL REVIEW. B, CONDENSED MATTER 1989; 39:10-14. [PMID: 9947115 DOI: 10.1103/physrevb.39.10] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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490
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Mai Z, Tao S, Zeng L, Zhang B. Computer simulations of a distorted reciprocal lattice of an Al-Li-Cu single quasicrystal. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 38:12913-12916. [PMID: 9946261 DOI: 10.1103/physrevb.38.12913] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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491
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Zeng L, Li SH, Lou ZC. [Morphological and histological studies of Chinese licorice]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1988; 23:200-8. [PMID: 3421109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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492
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Zeng L, Zhang RY, Wang X. [Studies on the constituents of Zizyphus spinosus Hu]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1987; 22:114-20. [PMID: 3618236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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