501
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Abstract
The Bacillus subtilis gene encoding gamma-glutamyltranspeptidase (GGT) activity encodes a protein of 587 amino acids having extensive homologies with other procaryotic GGTs. Inactivation of the gene abolished all measurable GGT activity, which in the wild type was found mainly to be excreted into the medium commencing at the end of vegetative growth.
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Affiliation(s)
- K Xu
- Department of Molecular and Experimental Medicine, Scripps Research Institute, La Jolla, California 92037, USA
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502
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Lam BK, Penrose JF, Rokach J, Xu K, Baldasaro MH, Austen KF. Molecular cloning, expression and characterization of mouse leukotriene C4 synthase. Eur J Biochem 1996; 238:606-12. [PMID: 8706658 DOI: 10.1111/j.1432-1033.1996.0606w.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Leukotriene C4 synthase (EC 2.5.1.37) catalyzes the conjugation of reduced glutathione (GSH) with leukotriene A4 to form the intracellular parent of the proinflammatory cysteinyl leukotrienes. Human leukotriene C4 synthase shares substantial amino acid identity in its consensus N-terminal two-thirds with 5-lipoxygenase-activating protein and has a region (residues 37-58) that exhibits 46% amino acid identity with a domain of this protein (residues 41 -62) to which an inhibitor binds. We have now cloned mouse leukotriene C4 synthase CDNA using the polymerase chain reaction to screen a mouse pcDNA3 expression library with oligonucleotide primers based on the translated human leukotriene C4 synthase cDNA sequence. Mouse leukotriene C4 synthase cDNA is 667 bp in length, including the poly(A)-rich tail, and shows 87% similarity with the human cDNA within the open reading frame. The deduced 150-amino-acid sequence of mouse leukotriene C4 synthase (differs from the human enzyme by only 18 amino acids, of which 9 reside at the C terminus. The potential N-glycosylation site, two protein kinase C phosphorylation sites, the two cysteine residues, and the putative inhibitor-binding domain (substitutions Thr4l-->Ser and Tyr50-->Phe) were conserved in mouse leukotriene C4 synthase. Northern blot analysis indicated that the leukotriene C4 synthase RNA transcript is widely distributed. The Km values for leukotriene A4 methyl ester, leukotriene A4 free acid and GSH were 7.6 microM, 3.6 microM and 1.6 mM, respectively, for purified human recombinant enzyme, and 10.3 microM, 2.5 microM and 1.9 microM, respectively, for purified recombinant mouse enzyme; the corresponding Vmax values were 2.5, 1.3 and 2.7 micromol x min(-1) x mg(-1) protein, respectively, for human enzyme, and 2.3, 1.2 and 2.2 micromol x min(-1) x mg(-1) protein, respectively, for mouse enzyme. The 5-lipoxygenase-activating-protein inhibitor, MK-886, was active against both human and mouse recombinant leukotriene C4 synthase with IC50 values of 3.1 microM and 2.7 microM respectively. These findings confirm that the leukotriene C4 synthases belong to a gene family that includes the 5-lypoxygenase-activating protein and suggest that the C-terminal domain of leukotriene C4 synthase may not be critical for its conjugation function.
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Affiliation(s)
- B K Lam
- Department of Medicine, Harvard Medical School, Boston, MA, USA
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503
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Xu K, Liu H, Yang S, Wang J. [A measurement of cytoplasmic estradiol and progesterone receptors in endometrium of patients with habitual abortion]. Hua Xi Yi Ke Da Xue Xue Bao 1996; 27:174-6. [PMID: 9389036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Estradiol and progesterone receptors in the endometrium of eight patients with habitual abortion in proliferative and secretory phases were measured by DCC. The serum estradiol (E2) and progesterone (P) were detected by radioimmunoassay, and the endometrium was histologically studied. The results showed that the level of serum E2 was normal in the proliferative and secretory phases. In 5/8 patients, the serum P level was below 11 ng/ml. The estradiol receptor of patients was not different from that of normal women in the proliferative and secretory phases, but the progesterone receptor was significantly lower than that of normal women in the proliferative and secretory phases. These suggest that the lower level of progesterone and progesterone receptor in the endometrium may be one of the causes of habitual abortion.
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Affiliation(s)
- K Xu
- Department of Obstetrics and Gynecology, Second Affiliated Hospital, Chengdu
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504
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Penrose JF, Spector J, Baldasaro M, Xu K, Boyce J, Arm JP, Austen KF, Lam BK. Molecular cloning of the gene for human leukotriene C4 synthase. Organization, nucleotide sequence, and chromosomal localization to 5q35. J Biol Chem 1996; 271:11356-61. [PMID: 8626689 DOI: 10.1074/jbc.271.19.11356] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Leukotriene C4 (LTC4) synthase catalyzes the conjugation of LTA4 with reduced GSH to form LTC4, the parent of the receptor active cysteinyl leukotrienes implicated in the pathobiology of bronchial asthma. Previous cloning of the cDNA for human LTC4 synthase demonstrated significant homology of its amino acid sequence to that of 5-lipoxygenase activating protein (FLAP) but none to that of the GSH S-transferase super-family. Genomic cloning from a P1 library now reveals that the gene for LTC4 synthase contains five exons (ranging from 71 to 257 nucleotides in length) and four introns, which in total span 2.52 kilobase pairs in length. The intron/exon junctions of LTC4 synthase align identically with those of FLAP; however, the small size of the LTC4 synthase gene contrasts with the > 31-kilobase pair size reported for FLAP. Confirmation of the LTC4 synthase gene size to ensure that no deletions had occurred during the cloning was obtained by two overlapping polymerase chain reactions from genomic DNA, which provided products of the predicted sizes. Primer extension analysis with poly(A)+ RNA from culture-derived human eosinophilic granulocytes or the KG-1 myelogenous cell line revealed multiple transcriptional start sites with prominent signals at 66, 69, and 96 base pairs 5' of the ATG translation start site. The 5'-flanking region revealed a GC-rich promoter sequence consistent with an SP-1 site and consensus sequences for AP-1 and AP-2 enhancer elements, 24, 807, and 877 bp, respectively, 5' from the first transcription initiation site. Southern blot analysis of a genomic DNA (with full-length cDNA as well as 5' and 3' oligonucleotide probes) confirmed the size of the gene and indicated a single copy gene in normal human genomic DNA. Fluorescent in situ hybridization mapped LTC4 synthase to chromosomal location 5q35, which is in close proximity to the cluster of genes for cytokines and receptors involved in the regulation of cells central to allergic inflammation and implicated in bronchial asthma.
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Affiliation(s)
- J F Penrose
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
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505
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Hu SP, Harrison C, Xu K, Cornish CJ, Geczy CL. Induction of the chemotactic S100 protein, CP-10, in monocyte/macrophages by lipopolysaccharide. Blood 1996; 87:3919-28. [PMID: 8611721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The murine S100 protein CP-10 is a potent chemotactic factor for murine and human myeloid cells in vivo and in vitro. This is the first report describing regulations of the CP-10 gene by a proinflammatory stimulus, lipopolysaccharide (LPS), in cells of the monocyte/macrophage lineage. Murine monocyte/macrophage-like WEHI 265 and RAW 264.7 cells preexposed to 5 to 50 ng/mL LPS expressed significant levels of CP-10 mRNA 4 hours, and maximal at 20 hours, after a secondary LPS challenge. This was accompanied by increasing levels of cell-associated and released CP-10 protein. In contrast, a single dose of LPS upregulated CP-10 mRNA in elicited peritoneal macrophages, whereas mRNA and protein levels decreased following LPS challenge. The state of macrophage differentiation may control responsiveness as LPS had no effect on CP-10 basal levels in bone marrow derived macrophages. LPS-induced CP-10 expression was controlled at the transcriptional level and nuclear run-on and protein synthesis inhibition assays indicated that LPS priming and challenge of RAW cells occurred via distinct pathways. MRP14, another S100 protein generally coordinately expressed with human MRP8, was not induced by LPS under the same conditions. We propose that CP-10 may play a key role in recruitment of leukocytes into tissues in response to gram-negative bacterial infection.
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Affiliation(s)
- S P Hu
- Immunology Group, Heart Research Institute, Sydney, NSW, Australia
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506
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Abstract
PURPOSE A mouse model was used to evaluate the consequences of partial cytoplasm removal, which mimics the consequence of human early embryo fragmentation, at the one-cell stage on embryonic development to the morula and blastocyst stages. RESULTS Opening the zona pellucida at the zygote stage has no detrimental effect on the number of differentiated or total cells at morula/blastocyst stage. However, reduced cytoplasm significantly affects the number of inner cell mass cells, 21.7 (10% cytoplasm removed) vs 27.6 (control) and 15.1 (20% cytoplasm removed) vs 24.7 (control). CONCLUSIONS The contribution of cytoplasm of maternal origin is critical to early embryonic development.
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Affiliation(s)
- K Xu
- Center for Reproductive Medicine and Infertility, Cornell University Medical College, New York, New York 10021, USA
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507
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He Y, Xu K, Zhang Q, Dai W, Xu Z, Liu B. [Inhibitory effect of tetrandrine on collagen synthesis of experimental hepatic fibrosis in rats]. Zhongguo Zhong Yao Za Zhi 1996; 21:177-9, 192. [PMID: 9206262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Y He
- Research Center of Beijing Ditan Hospital
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508
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Xu K, Clark D, Strauch MA. Analysis of abrB mutations, mutant proteins, and why abrB does not utilize a perfect consensus in the -35 region of its sigma A promoter. J Biol Chem 1996; 271:2621-6. [PMID: 8576231 DOI: 10.1074/jbc.271.5.2621] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The Bacillus subtilis global regulator AbrB is a DNA-binding protein composed of six identical monomers of 96 amino acids that shows specificity to the promoter regions of its target genes including its own. We have sequenced thirteen previously uncharacterized abrB mutations. Four mutant AbrB proteins were purified, and their DNA-binding properties and multimeric structures were examined. AbrB23 (R25S) had no appreciable DNA binding activity but retained a hexameric structure, indicating that Arg25 is important in DNA interactions. Three other mutant proteins, AbrB1 (C56Y), AbrB19 (Gln83-->termination codon), and AbrB100 (L69P), showed decreased DNA binding and altered multimeric interactions. Analysis of the expression and AbrB binding affinities of mutant abrB promoters demonstrated that a consensus -35 region is incompatible with proper autoregulation of the abrB gene.
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Affiliation(s)
- K Xu
- Department of Molecular and Experimental Medicine, Scripps Research Institute, La Jolla, California 92037, USA
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509
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Yang G, Xu K, Luo Q. [Clinical study of scopolamine detoxification for the treatment of heroin addicts]. Zhonghua Yi Xue Za Zhi 1996; 76:141-4. [PMID: 8758450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To evaluate the efficacy of treatment of heroin addicts (n = 100) by scopolamine detoxification (10 days program). METHODS Methadone detoxification (10 days program) group (n = 50) and clonidine treated group (n = 50) served as controls. RESULTS The scores of abstinence syndrome in scopolamine detoxification group were lower that those in clonidine treated group in the first three days of protocol, but this difference disappeared in the late stage of treatment. While scopolamine detoxification was effective as methadone detoxification in the control of abstinence syndrome during the first five days of treatment but the difference in the scores of abstinence syndrome between scopolamine and methadone group was observed during the late five days of protocol. The side-effects produced by scopolamine in general were dry mouth, somnolence, tachycardia, blurred vision and so on, which relieved gradually or disappeared with decreasing of its doses. CONCLUSION Scopolamine does not result in potential dependence and has definite curative effect in the treatment of heroin addiction.
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Affiliation(s)
- G Yang
- Ningbo Drug Withdrawal Research Center
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510
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Shen GG, Zhuo XL, Zhang XM, Xu K. [Solubilization of beta-bungarotoxin-binding protein from rat diaphragm and inhibition of its binding by some other presynaptic neurotoxins]. Sheng Li Xue Bao 1996; 48:94-7. [PMID: 8758698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The mechanism of the transmitter release-blocking action of beta-bungarotoxin at neuromuscular junctions is probably related to the binding of the toxin to a presynaptic voltage-dependent K+ channel. In this paper we report the solubilization of beta-bungarotoxin-binding protein from rat diaphragm membrane preparations with Triton X-100. The specific binding activities of the detergent extracts are 200-400 fmol/mg of protein, and the yields are about 50%-70%. The binding of 125I-beta-bungarotoxin to the extracts could be completely inhibited by dendrotoxin, with an IC50 of about 8 x 10(-8) mol.L. Another beta-neurotoxin, beta-agkistrodotoxin, however, could not inhibit the 125I-beta-bungarotoxin binding at all. This indicates that the acting sites of beta-agkistrodotoxin on the presynaptic membranes are different from those of beta-bungarotoxin.
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Affiliation(s)
- G G Shen
- Shanghai Institute of Physiology, Chinese Academy of Sciences
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511
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Xu K, Strauch MA. In vitro selection of optimal AbrB-binding sites: comparison to known in vivo sites indicates flexibility in AbrB binding and recognition of three-dimensional DNA structures. Mol Microbiol 1996; 19:145-58. [PMID: 8821944 DOI: 10.1046/j.1365-2958.1996.358882.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The AbrB protein of Bacillus subtilis regulates expression of numerous genes, primarily through specific binding interactions to DNA regions containing transcriptional promoters. Although over 15 target regions for AbrB binding to chromosomally located sequences have been analysed by DNase I footprinting, no obvious consensus sequence or motif has yet emerged from their examination. Using in vitro selection techniques, we have isolated optimal AbrB-binding sites from oligonucleotides containing 22 or 44 random base pairs. The best of these sites have an apparent in vitro Kd which is fivefold lower than a similar-sized DNA fragment containing the sequence corresponding to the AbrB-binding site on the spo0E gene. We tested one of the sites in vivo and found that it confers AbrB-mediated control upon a promoter not normally regulated by AbrB. In each of four separate trials, the selected sites possess motifs that converge to a simple consensus. It is argued that the nature and spacing of these motifs produce a type of three-dimensional DNA structure recognizable by AbrB, and that known in vivo sites, which lack these motifs, possess an approximation of the optimal structural determinant.
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Affiliation(s)
- K Xu
- Department of Molecular and Experimental Medicine, Scripps Research Institute, La Jolla, California 92037, USA
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512
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Xu K, Dluzen DE. L-DOPA modulation of corpus striatal dopamine and dihydroxyphenylacetic acid output from intact and 6-OHDA lesioned rats. J Neural Transm (Vienna) 1996; 103:1295-305. [PMID: 9013416 DOI: 10.1007/bf01271190] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In the present report we examined the differences in in vitro dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) efflux from the corpus striatum (CS) of intact versus 6-hydroxydopamine (6-OHDA) lesioned (in substantia nigra) male rats in response to different doses of two pulse infusions of L-dihydroxyphenylalanine (L-DOPA). In the first experiment, we tested the effects of two 20-min infusions of 5 uM L-DOPA. In the second experiment we repeated this protocol using 50 uM L-DOPA. There was an overall significantly greater output of DA for intact versus 6-OHDA lesioned rats for both doses. Moreover, in Experiment 1, the 5 uM L-DOPA produced a peak DA response to the second infusion which was significantly higher than that of the first infusion in the intact, but not lesioned rats. In Experiment 2, the 50 uM L-DOPA group showed no significant differences in DA output between the two infusions for both intact and lesioned rats. In contrast to DA responses, there were no overall significant differences in DOPAC output between intact and 6-OHDA lesioned rats for both doses. However, for both doses tested, the peak DOPAC output from the second infusion was significantly increased in lesioned, but not intact rats. These data demonstrate that L-DOPA evoked DA and DOPAC output are differentially modulated in intact and 6-OHDA lesioned striatum. The lesions of the striatal dopaminergic system may alter these responses through changes in intraneuronal storage and metabolism of DA following L-DOPA infusion.
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Affiliation(s)
- K Xu
- Department of Anatomy, Northeastern Ohio Universities College of Medicine, Rootstown, USA
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513
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Xu K, Hu S. Home care for the elderly. World Health Forum 1996; 17:357-9. [PMID: 9060229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- K Xu
- Department of Health Economics, Shanghai Medical University, China
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514
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Xu K, He FX, Zhang HG, Zhang XT, Han MJ, Wang CR, Kaneko M, Takahashi M, Okawada T. Budd-Chiari syndrome caused by obstruction of the hepatic inferior vena cava: immediate and 2-year treatment results of transluminal angioplasty and metallic stent placement. Cardiovasc Intervent Radiol 1996; 19:32-6. [PMID: 8653743 DOI: 10.1007/bf02560144] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE To assess the usefulness of percutaneous transluminal angioplasty (PTA) and expandable metallic stent (EMS) placement for treatment of Budd-Chiari syndrome (BCS). METHODS Thirty-two patients with BCS were treated by PTA alone or by PTA and EMS placement. Among the 32 patients, a membranous obstruction was found in 24 and a segmental stenosis or occlusion in 8 patients. The follow-up period for PTA was 38-68 months (mean 52.2 months); for EMS it was 20-36 months (mean 24.3 months). RESULTS Twenty-one patients underwent PTA as the primary treatment. Of these, one patient died of disseminated intravascular coagulation shortly after the procedure; 20 had good to excellent initial angiographic and clinical results. Of the 20, restenosis or reocclusion developed in 10 patients (48%), all before 27 months; 8 patients (38%) became symptomatic, and 2 remained symptom-free for a total recurrent obstruction rate of 50%. The EMS group of 17 patients included 11 patients who underwent primary stenting and 6 patients with secondary stenting after recurrence following primary PTA; restenosis was demonstrated in only 2 patients (12%). CONCLUSIONS We conclude that PTA alone produces excellent short-term results and about 50% sustained patency after 2 years in patients with BCS; therefore it should remain the procedure of first choice. Stents should be reserved for primary or secondary PTA failures.
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Affiliation(s)
- K Xu
- Department of Radiology, First Teaching Hospital of China Medical University, Shenyang, China
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515
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Abstract
Alterations in the cardiac alpha1-adrenoceptor and its subtypes in thyroxine-treated rats were studied by means of radioligand binding assays, measurement of contractile response and reverse transcription-polymerase chain reaction (RT-PCR). The results showed that in thyroxine-treated rats the cardiac alpha1-adrenoceptor density (Bmax) was reduced from 51.6 +/- 6.0 fmol/mg in control to 40.9 +/- 3.7 fmol/mg (P<0.01); and the percentage of high affinity sites for 5-methyl-urapidil decreased from 23.3 +/- 2.0% in control to 10.8 +/- 2.0% in thyroxine-treated rats (P<0.05). The data indicated that the high-affinity sites for 5-methyl-urapidil (alpha1A-adrenoceptor) were reduced (from 12.0 to 4.4 fmol/mg), but the low-affinity sites for 5-methyl-urapidil (alpha1B- plus alpha1D-adrenoceptor) were not changed (from 39.6 to 36.5 fmol/mg). RT-PCR showed that steady-state levels of mRNA for alpha1A- and alpha1B-adrenoceptors were decreased, while that for alpha1D-adrenoceptor was raised in thyroxine-treated rats. In the isolated electrically driven left atria the phenylephrine-induced maximal contractions were reduced from 258 +/- 17 mg in control to 188 +/- 24 mg in thyroxine-treated rats (P<0.05). The pA2 values of 5-methyl-urapidil were reduced from 8.89 +/- 0.36 in control to the hyperthyroidism of 7.87 +/- 0.43 in thyroxine-treated rats (P<0.05). Chlorethylclonidine preincubation shifted concentration-response curves for phenylephrine to the right and reduced the maximal response to a lesser extent in thyroxine-treated rats than in control rats. Thus we concluded that the total number of cardiac alpha1-adrenoceptors is reduced in thyroxine-treated rats. The change is subtype selective, with alpha1A- and alpha1B-adrenoceptors being reduced in number and alpha1D-adrenoceptor being increased.
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Affiliation(s)
- C Han
- Institute of Vascular Medicine, Third Hospital, Beijing Medical University, People's Republic of China
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516
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Xu Y, Xu K, Ji P. [Significance of immunohistochemical study in the diagnosis and differential diagnosis of chordoma]. Zhonghua Zhong Liu Za Zhi 1995; 17:435-7. [PMID: 8697996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Seven cases of chordoma were studied immunohisto-chemically with antibodies directed to epithelium, nerve, mesenchyme, muscle and histiocyte. Six cases of chondrosarcoma and three cases of mucinous carcinoma of colon were studied as control. The results showed that the chordomas were positive for cyto-K 6/7, EMA 7/7, CEA 6/7, Vim 7/7, S-100 7/7, alpha-AT 7/7, Lyso 4/7, while negative for GFAP and Des in all 7 cases indicating that chordoma, just like notochord, had the potentiality of multidirectional differentiation. In contrast, none of the chondrosarcomas was positive for cyto-K, EMA or CEA, but positive for Vim and S-100 in 6 cases. Three cases of colon mucinous carcinoma were positive for epithelial antibodies, but none reacted with other antibodies. Thus, immunohistochemical studies are of help in the diagnosis and differential diagnosis of chordoma.
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Affiliation(s)
- Y Xu
- Department of Pathology, Qingdao Municipal Hospital
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517
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518
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Affiliation(s)
- B K Lam
- Department of Medicine, Harvard Medical School, Boston, MA, USA
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519
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Penrose JF, Spector J, Lam BK, Friend DS, Xu K, Jack RM, Austen KF. Purification of human lung leukotriene C4 synthase and preparation of a polyclonal antibody. Am J Respir Crit Care Med 1995; 152:283-9. [PMID: 7599836 DOI: 10.1164/ajrccm.152.1.7599836] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Leukotriene (LT) C4 synthase is an integral membrane protein that catalyzes the conjugation of LTA4 to reduced glutathione to form LTC4. LTC4 synthase has been cloned and characterized from transformed cell lines, but the protein has not been defined from a tissue source. LTC4 synthase was purified to homogeneity from human lung tissue, utilizing S-hexyl glutathione chromatography followed by LTC4 affinity chromatography. A greater than 100,000-fold purification with a yield of 8 to 25% (n = 4) was achieved. The purified LTC4 synthase migrated in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) as an 18-kD protein, and its 19 N-terminal amino acid sequence is identical to that of purified LTC4 synthase from KG-1 myeloid cells or from expression cloning of a KG-1 library in COS cells. Using a rabbit polyclonal IgG raised against purified LTC4 synthase, SDS-PAGE immunoblotting of LTC4 synthase from human lung tissue, eosinophils, KG-1 cells, and platelets showed an 18-kD protein. Immunofluorescence staining of alveolar macrophages in human lung sections with the anti-LTC4 synthase IgG revealed LTC4 synthase to be largely perinuclear in distribution. Thus, LTC4 synthase, the biosynthetic enzyme responsible for the formation of cysteinyl LTs, is present in lung tissue in a form apparently identical to that of hematopoietic cells.
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Affiliation(s)
- J F Penrose
- Department of Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
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520
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Gormus BJ, Xu K, Cho SN, Baskin GB, Bohm RP, Martin LN, Blanchard JL, Mack PA, Ratterree MS, Meyers WM. Experimental leprosy in monkeys. II. Longitudinal serological observations in sooty mangabey monkeys. LEPROSY REV 1995; 66:105-25. [PMID: 7637522 DOI: 10.5935/0305-7518.19950013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In this study, 11 SMM were grouped and inoculated with differing doses of SMM-origin Mycobacterium leprae (ML) between 4.5 x 10(8) and 1 x 10(9) by either combined IV/IC routes or by IV or IC route alone. The combined route was the most effective in eliciting progressive, disseminated LL leprosy. In all, 6 of 7 SMM inoculated by the combined routes developed leprosy requiring treatment at some point. Only 1 of 4 inoculated by a single route developed persisting leprosy requiring chemotherapy. Either no disease or spontaneous regression of initial disease occurred in the other 3 animals inoculated by a single route. Doses in excess of 1 x 10(9) ML were more effective than lesser doses. An association was observed between the development of IgG anti-PGL-I ELISA OD values and resistance to leprosy and between IgM anti-PGL-I and leprosy progression or susceptibility. Serum PGL-I antigen levels, determined by dot ELISA, paralleled disease severity longitudinally. High positive OD values of anti-LAM IgG prior to ML inoculation were observed in the majority of leprosy-susceptible SMM in contrast to negative levels in more resistant animals. Anti-LAM IgG OD values exceeded the positive cut-off point after inoculation in 5 of 11 SMM; 3 of these 5 had concurrent detectable serum levels of PGL-I antigen.
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Affiliation(s)
- B J Gormus
- Department of Microbiology, Tulane Regional Primate Research Center, Covington, LA, USA
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521
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Abstract
The effect of plasma from a myasthenia gravis (MG) patient, containing anti-presynaptic membrane receptor (PsmR) antibody on the membrane currents of motor nerve ending was investigated in mouse intercostal nerve triangularis sterni preparations by perineurial recording. After inhibition of both the fast K+ current and Ca(2+)-dependent K+ current by 30 mM Tetraethyl-ammonium (TEA) unmasked the voltage dependent fast Ca2+ current and the "Ca plateau", which was contributed by the voltage-dependent slow Ca2+ current and slow K+ current. Application of the MG plasma caused further prolongation and increase of the Ca plateau, due to blockage of the slow K+ current. This effect was observed immediately after the application and could be partially reversed by washing, whereas no change was found by addition of the plasma from healthy persons. When K+ current was completely blocked by 30 mM TEA and 300 microM 3,4-diaminopyridine (3,4-DAP), the fast Ca2+ current and the slow Ca2+ current were revealed. Neither the fast nor the slow Ca2+ current could be affected by the MG plasma; It was also shown that the MG plasma was devoid of noticeable effect on the voltage dependent Na+ current, fast K+ current as well as the Ca(2+)-dependent K+ current. So the effect of the MG plasma with antibody to PsmR was concluded to inhibit the slow K+ current selectively. As we knew, the beta-bungarotoxin binding protein was a kind of K+ channel, these results further confirmed that the beta-bungarotoxin binding protein should be the target of the antibody to PsmR found in the plasma of some patients suffering from MG.
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Affiliation(s)
- Y Shi
- Shanghai Institute of Physiology, Chinese Academy of Sciences
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522
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Gormus BJ, Xu K, Baskin GB, Martin LN, Bohm RP, Blanchard JL, Mack PA, Ratterree MS, McClure HM, Meyers WM. Experimental leprosy in monkeys. I. Sooty mangabey monkeys: transmission, susceptibility, clinical and pathological findings. LEPROSY REV 1995; 66:96-104. [PMID: 7637533 DOI: 10.5935/0305-7518.19950012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A total of 31 sooty mangabey monkeys (SMM) (Cercocebus torquatus atys) inoculated by various routes with differing numbers of SMM-origin Mycobacterium leprae (ML) and 4 SMM inoculated with human-origin ML were observed for 4-12 years. SMM-origin ML was more pathogenic in SMM than human-origin ML. The spectrum of disease ranged from indeterminate to borderline and lepromatous in different animals. Some animals developed pure neural leprosy. Erythema nodosum leprosum (SNL) was also observed. Combined intravenous/intracutaneous (IV/IC) routes of inoculation more effectively induced advancing, disseminated lepromatous forms of leprosy; IV or IC routes alone were less effective at comparable doses. Total IV/IC doses of SMM-origin ML equal to or greater than 5 x 10(8), with morphologic indices (MIs) ranging from 5 to 10%, produced advancing, disseminated LL leprosy in 92% of SMM. Lower IV/IC doses and inoculations by a single IV or IC route produced fewer leprosy infections and more spontaneous regressions. As a species, captive SMM are highly susceptible to experimental leprosy and provide an excellent model for the longitudinal study of leprosy.
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Affiliation(s)
- B J Gormus
- Department of Microbiology, Tulane Regional Primate Research Center, Covington, LA, USA
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523
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Abstract
The existence of beta-adrenoceptor (beta-AR) in endothelium of rabbit coronary artery and its alteration in atherosclerosis (AS) were determined by relaxation experiments in isolated preparations and in situ hybridization with a digoxigenin-labelled beta 2-AR cDNA probe. The concentration-relaxing response curves for isoproterenol (ISO) and norepinephrine (NE) in the presence of phentolamine were shifted to the right, and the maximal relaxations were reduced by removing the endothelium. Nitric oxide synthase inhibitor L-NG-nitro-arginine reduced the maximal relaxation induced by ISO, while the cyclooxygenase inhibitor indomethacin showed no effect on relaxation. In situ hybridization showed that mRNA for beta-AR was detected not only in smooth muscles, but also in endothelial cells. Coronary artery AS was created by high cholesterol feeding and was confirmed histologically under light microscopy. The relaxation response to acetylcholine (ACh) was abolished or significantly diminished in AS preparations. The relaxation responses to ISO or NE, however, were potentiated in AS arteries, especially in those which showed diminished (but not abolished) ACh response. The relaxation induced by sodium nitroprusside was reduced significantly in the AS arteries. Those results suggest that beta-AR are present in endothelium of rabbit coronary artery, and that endothelium beta-AR-mediated vasorelaxation is potentiated in AS.
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MESH Headings
- Animals
- Arginine/analogs & derivatives
- Arginine/pharmacology
- Arteriosclerosis/physiopathology
- Cholesterol, Dietary
- Coronary Vessels/drug effects
- Coronary Vessels/physiology
- Coronary Vessels/physiopathology
- DNA Probes
- Diet, Atherogenic
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/physiology
- Endothelium, Vascular/physiopathology
- Enzyme Inhibitors/pharmacology
- Female
- In Vitro Techniques
- Indomethacin/pharmacology
- Isoproterenol/pharmacology
- Male
- Muscle Contraction
- Muscle Relaxation/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Muscle, Smooth, Vascular/physiopathology
- Nitric Oxide Synthase/antagonists & inhibitors
- Nitroarginine
- Norepinephrine/pharmacology
- Rabbits
- Receptors, Adrenergic, beta/biosynthesis
- Receptors, Adrenergic, beta/physiology
- Receptors, Adrenergic, beta-2/biosynthesis
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Affiliation(s)
- Z Lu
- Institute of Vascular Medicine, Beijing Medical University, China
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524
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Xu K, Yu X, Kong Y, Wang Y, Li Z. HBV surface antigen proteins with deletions in the preS region. Sci China B 1995; 38:320-7. [PMID: 7766314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Four pairs of HBV surface antigen genes, in which the preS region was partially deleted, were constructed by the polymerase chain reaction (PCR). The comparison of the levels of the expression in mammalian cells of these genes and the ones constructed before, and the properties of these gene products showed that the missing of a part of the preS region did not affect the overall spatial structure of the S region and the surface localization of the preS region. The removal of the preS1 retention sequence (a. a. 2-19) alleviated significantly the shelter of the major antigenic determinants in the S region by the preS sequence. It was found that the long preS region seriously impaired the secretion of the surface antigen proteins from mammalian cells. In addition to the previously reported preS1 retention sequence, the preS1 sequence (a.a. 48-65) may also inhibit the secretion of the surface antigen proteins, whereas the preS2 region exerts no major influence on the retention of the large surface antigen protein. One of the expressed surface antigen proteins, in which the preS1 sequence (a.a. 21-47) and the S region were directly fused, deserves further study and may be developed into a new HBV vaccine which contains the preS1 binding site for hepatocyte receptors due to its stability, fine secretability and strong preS1 antigenicity.
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Affiliation(s)
- K Xu
- Shanghai Institute of Biochemistry, Chinese Academy of Sciences
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525
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Ohkawa S, Xu K, Wilson LA, Montelaro R, Martin LN, Murphey-Corb M. Analysis of envelope glycoprotein-specific antibodies from SIV-infected and gp110-immunized monkeys in ACC and ADCC assays. AIDS Res Hum Retroviruses 1995; 11:395-403. [PMID: 7786584 DOI: 10.1089/aid.1995.11.395] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Sera collected from SIV-infected or recombinant glycoprotein-immunized monkeys were characterized for antibodies participating in antibody-complement-mediated cytolysis (ACC) and antibody-dependent cellular cytolysis (ADCC) in terms of their IgG subclass and epitope specificity. In a competitive inhibition ELISA, gp110-specific antibody reactivity with nondenatured rgp110 was blocked completely by soluble homologous rgp110 and partially inhibited by heterologous rgp110, suggesting cross-reactivity between viral strains. However, only partial inhibition was observed with denatured recombinant gp140 (rgp140) in selected monkeys, indicating that the majority of gp110-specific antibodies recognized conformational epitopes. ACC activity against recombinant vaccinia-infected, envelope-expressing targets was found in sera from both infected and immunized monkeys, whereas ADCC activity was observed only in sera from infected monkeys. ACC was blocked with denatured rgp140 as well as nondenatured rgp110, indicating that ACC-mediating antibodies recognized mainly linear epitopes. In contrast, rgp140 did not compete as effectively as rgp110 in the ADCC assay, indicating that the majority of ADCC antibodies recognized conformational epitopes. Competitive inhibition using three peptide fragments of gp110 indicated that epitopes recognized by ACC antibodies lie within amino acid residues 214-471, a region that spans V3, whereas ADCC-reactive epitopes lie between amino acid residues 52 and 214 at the N-terminal end of gp110. Column chromatography of rhesus IgG resulted in three subclass-enriched fractions, designated IgG-I, IgG-II, and IgG-III. IgG-I, but not IgG-II or IgG-III, from both infected and immunized monkeys mediated ACC, whereas IgG-I and IgG-II from infected monkeys mediated ADCC.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- S Ohkawa
- Department of Microbiology, Tulane Regional Primate Research Center, Covington, Louisiana 70433, USA
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526
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Ji Y, Lu L, Xu K, Hattori H, Terakawa S. Purification and partial amino acid sequences of a new presynaptic toxin and a cytotoxin from venom of pit veper Agkistrodon blomhoffii brevicaudus. Sci China B 1995; 38:169-178. [PMID: 7755871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The technique of the reverse-phase performance liquid chromatography (RP-HPLC) was employed to separate and purify the toxic proteins from the venom of Agkistrodon blomhoffii brevicaudus collected in China. 3 toxic proteins marked as AgTx-1, AgTx-2 and AgTx-3 consisting of about 122 amino acid residues were screened. The toxicities (LD50) of the AgTx-1, AgTx-2 and AgTx-3 were 0.075, 0.51 and 6.6 mg per kg weight of mice respectively. Toxicological experiment in the chick biventer cervicis nerve-muscle preparation showed that the acetylcholine (Ach) sensitivity of the preparation was unchanged after the total failure of the indirect contraction caused by AgTx-1 and AgTx-2, suggesting that they were presynaptic blockers, namely beta-type of snake toxins. However, the amplitude of indirect contraction of the preparation was gradually reduced due to its incomplete relaxation caused by AgTx-3, indicating that it should belong to the category of cytotoxins. The partial amino acid sequences of 3 toxins have been established. It was found in ref. [1] that the sequences of the first 32 N-terminal amino acid residues of AgTx-1 and AgTx-2, as well as beta-agkistrodotoxin (beta-AgTx) reported previously were identical (the residue at the position 30 of beta-AgTx should be Trp). In view of the similarity in toxicities, and the amounts in the venom and other properties, it was concluded that AgTx-1 should be beta-AgTx and consequently was renamed beta 1-AgTx. AgTx-2 should be the isoform of beta 1-AgTx, and correspondingly named beta 2-AgTx.
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Affiliation(s)
- Y Ji
- Shanghai Institute of Physiology, Chinese Academy of Sciences
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527
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528
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Abstract
STUDY OBJECTIVE To characterize the activities of the P450 mixed-function oxidase CYP1A2 as well as the cytosolic enzymes N-acetyltransferase and xanthine oxidase using caffeine as a probe in children with cystic fibrosis compared to age-matched healthy control subjects. METHODS After administration of caffeine (cola beverage) to 12 children with cystic fibrosis (age range, 5 to 11 years) and 12 healthy control subjects (age range, 5 to 12 years), urine was collected for 4 hours. Caffeine metabolites were determined by HPLC, and urinary caffeine metabolite ratios were computed to determine liver enzyme activities. In addition, a blood sample was used to detect cystic fibrosis mutant alleles by polymerase chain reaction. RESULTS The indexes for CYP1A2, N-acetyltransferase, and 8-hydroxylation were similar in both groups of subjects. In contrast, there was a significant difference in the frequency distribution of the xanthine oxidase activity between the two groups. Nine of 12 patients with cystic fibrosis but only one of 12 healthy volunteers had xanthine oxidase activities above 0.42 (Kolmogorov-Smirnov two-sample test, p < 0.01). CONCLUSIONS Differences in xanthine oxidase may have clinical implications with regard to interindividual variation in xenobiotic biotransformation and the exposure to lung tissue-damaging oxygen radicals. Hepatic enzyme activities appear to be selectively altered in patients with cystic fibrosis.
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Affiliation(s)
- B A Hamelin
- Ecole de Pharmacie, Laboratoire de Pharmacocinétique Clinique, Cité Universitaire, Université Laval, Québec, Canada
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529
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Xu HJ, Xu K, Zhou Y, Li J, Benedict WF, Hu SX. Enhanced tumor cell growth suppression by an N-terminal truncated retinoblastoma protein. Proc Natl Acad Sci U S A 1994; 91:9837-41. [PMID: 7937901 PMCID: PMC44912 DOI: 10.1073/pnas.91.21.9837] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The retinoblastoma (RB) gene encodes a nuclear phosphoprotein of 928 amino acids (pRB). Thus far, much effort in RB research has been focused on both the viral oncoprotein-binding domains and the C-terminal domain, whereas little is known about the N-terminal moiety of the protein. We report here that an N-terminal truncated RB protein of approximately 94 kDa (pRB94) exerts more potent cell growth suppression as compared to the full-length pRB protein in a diversity of tumor cell lines examined, including those having a normal endogenous RB gene. Tumor cells transfected with the pRB94-expressing plasmids displayed multiple morphological changes frequently associated with cellular senescence and/or apoptosis. They failed to enter S phase and rapidly died. The pRB94 expressed in recipient tumor cells had a longer half-life than the full-length pRB protein and tended to remain in an active un- or hypophosphorylated form. Since it has also been found that N-terminal truncated RB proteins often accumulated in growth-arrested and/or differentiated tumor cells, we suggest that N-terminal truncation of pRB may be one of the cellular mechanisms modulating the RB protein function in cell-cycle control.
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Affiliation(s)
- H J Xu
- Center for Biotechnology, Baylor College of Medicine, Woodlands, TX 77381
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530
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Feng D, Chen H, Xia S, Xu K. Optical bipolar kth-order neural network based on inner-product representation. Appl Opt 1994; 33:6235-6238. [PMID: 20936042 DOI: 10.1364/ao.33.006235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A new polarization-encoding scheme for a bipolar kth-order neural network based on inner-product representation is proposed. Bipolar data multiplication is achieved as the rotation of linearly polarized light. A compact architecture of the bipolar kth-order neural network is suggested. In the architecture, no subtractions are needed, and the threshold levels for the neurons are fixed. Also, we show that a liquid-crystal device such as a liquid-crystal television is acceptable as a polarization modulator in the proposed architecture by computer simulation.
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531
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Liu Z, Zhang H, Xu J, Qian X, Qiao Y, Lin C, Xu K. Signature of non-compound-nucleus fission at sub-barrier energies. Phys Rev C Nucl Phys 1994; 50:1717-1719. [PMID: 9969835 DOI: 10.1103/physrevc.50.1717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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532
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Ji YH, Hattori H, Xu K, Terakawa S. Molecular characteristics of four new depressant insect neurotoxins purified from venom of Buthus martensi Karsch by HPLC. Sci China B 1994; 37:955-63. [PMID: 7993579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Suitable pattern and high yield were obtained when the reverse-phase performance liquid chromatography (RP-HPLC) was used to separate neurotoxins from venom of Chinese scorpion Buthus martensi Karsch. Using this technique, the venom was first separated to two main regions. The toxicity tests show that the insect-selective neurotoxical components are concentrated in the latter region, from which five insect-selective neurotoxins designated by BmK IT1-IT5 were obtained. According to the results of the toxicity test as well as the amino acid composition and N-terminal analyses, BmK IT1 is the excitatory insect neurotoxin as reported in a previous paper, and the others are the newly found depressant insect-selective neurotoxins. The molecules of all the four toxins are single-chain minipeptides of about 60 amino acids. Their isoelectric points (pI) are between 8.3 and 8.5. The fact that BmK IT2 loses completely its insect toxicity after being modified by fluorochrome shows that the positive charges on the molecular surface of this kind of toxins are important to maintaining the bioactivity of the molecules.
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Affiliation(s)
- Y H Ji
- Shanghai Institute of Physiology, Academia Sinica, PRC
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533
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Zhang LF, Xu K, Li XM. [Quantitative study on DNA-adduct in normal lung tissues of smoking and non-smoking lung cancer patients]. Zhonghua Yu Fang Yi Xue Za Zhi 1994; 28:206-9. [PMID: 7842879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Lung tissues from 32 cases of lung cancer with surgical operation, 22 smokers and 10 nonsmokers, were analyzed with P1-mediated modification of 32P-postlabelling technique. The level of lung DNA-adduct in cigarette smokers was higher that in nonsmokers with significant difference (P < 0.001). Autoradiogram showed a diagonal radioactive zone in smokers' lung tissues. Correlation analysis indicated DNA-adduct in lung tissues increased with the number of cigarettes smoked with a regression equation of Y = 0.411 X + 3.52, r = 0.74, P < 0.001.
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Affiliation(s)
- L F Zhang
- Institute of Environmental Health and Engineering, Chinese Academy of Preventive Medicine, Beijing
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534
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Xu K, Elliott T. Cloning, DNA sequence, and complementation analysis of the Salmonella typhimurium hemN gene encoding a putative oxygen-independent coproporphyrinogen III oxidase. J Bacteriol 1994; 176:3196-203. [PMID: 8195073 PMCID: PMC205488 DOI: 10.1128/jb.176.11.3196-3203.1994] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Coproporphyrinogen oxidation is a last step in heme biosynthesis. The biochemically characterized eukaryotic coproporphyrinogen III oxidases have an obligate requirement for molecular oxygen, and a similar enzyme is encoded by the hemF gene in Salmonella typhimurium. Anaerobic heme synthesis requires an oxygen-independent coproporphyrinogen oxidase, which is probably encoded by the hemN gene in S. typhimurium. The hemN gene has been cloned from an insertion mutant. The nucleotide sequence was obtained and used for PCR amplification of the wild-type gene. A single open reading frame was identified as the hemN gene on the basis of its interruption by the insertion mutation and plasmid complementation studies of hemF hemN double mutants. The predicted HemN protein has 38% amino acid sequence identity to a putative anaerobic Rhodobacter sphaeroides coproporphyrinogen oxidase. The hemN RNA 5' end and the inferred transcription initiation site were mapped by primer extension. The 52.8-kDa HemN protein is expressed from the second ATG codon of the hemN open reading frame. An open reading frame with an unknown function directly upstream of hemN has a striking amino acid sequence, including 11 acidic residues in a row.
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Affiliation(s)
- K Xu
- Department of Microbiology, University of Alabama at Birmingham 35294
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535
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Zhou Y, Li J, Xu K, Hu SX, Benedict WF, Xu HJ. Further characterization of retinoblastoma gene-mediated cell growth and tumor suppression in human cancer cells. Proc Natl Acad Sci U S A 1994; 91:4165-9. [PMID: 8183886 PMCID: PMC43745 DOI: 10.1073/pnas.91.10.4165] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We have transfected the osteosarcoma cell line Saos2 and the bladder carcinoma cell line 5637 with additional retinoblastoma (RB) expression plasmids. The RB-reconstituted Saos2 and 5637 cells showed only slightly lower ratios of cells undergoing DNA synthesis compared to their parental RB- tumor cells, and there were no noticeable changes in cell morphology. Furthermore, we have isolated long-term RB+ clones from Saos2, 5637, and the retinoblastoma cell line WERI-Rb27 after transfection/transduction with a RB expression plasmid or retrovirus. These clones were similar to their parental cell lines in terms of morphology and growth rates, and they all expressed functional RB protein (p110RB) as evidenced by its potential of phosphorylation, simian virus 40 large tumor antigen binding, and nuclear tethering. No mutation or deletion of the exogenous RB gene was detectable by PCR and single-strand conformation polymorphism analysis. In addition, either the individual or pooled RB+ clones did form malignant tumors in nude mice but usually with a longer latency period and lower frequency. Such tumors also retained normal RB expression, suggesting that at least a portion of the RB-reconstituted tumor cells were still tumorigenic. This phenomenon is referred to by us as tumor suppressor resistance (TSR).
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Affiliation(s)
- Y Zhou
- Center for Biotechnology, Baylor College of Medicine, The Woodlands, TX 77381
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536
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Kashala O, Marlink R, Ilunga M, Diese M, Gormus B, Xu K, Mukeba P, Kasongo K, Essex M. Infection with human immunodeficiency virus type 1 (HIV-1) and human T cell lymphotropic viruses among leprosy patients and contacts: correlation between HIV-1 cross-reactivity and antibodies to lipoarabinomannan. J Infect Dis 1994; 169:296-304. [PMID: 7906291 DOI: 10.1093/infdis/169.2.296] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
To determine the association between leprosy and human retroviral infections, 57 leprosy patients, 39 leprosy contacts, and 500 pregnant women were investigated serologically for antibodies to human immunodeficiency virus type 1 (HIV) and human T cell lymphotropic virus (HTLV) types I and II. Antibodies to Mycobacterium leprae phenolic glycolipid I (PGL-I), and lipoarabinomannan (LAM) were also analyzed. A low prevalence of HIV-1 infection was observed among leprosy patients (3.5%), leprosy contacts (0), and pregnant women (3.6%). Antibodies to HTLV-I but not -II were found more often in leprosy patients (8.7%) and contacts (12.8%) than in pregnant women (0). Sera from leprosy patients and leprosy contacts were often false-positive for HIV-1 by ELISA and were indeterminate by Western blot. LAM IgM and PGL-I IgM antibodies in sera from leprosy patients yielded significant cross-reactivities with HIV-1 pol and gag proteins. These data suggest that mycobacterial cell wall antigens may share common epitopes with HIV. Caution should be exercised when interpreting HIV-1 ELISA and Western blot data from regions where leprosy or other mycobacterial diseases are endemic.
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Affiliation(s)
- O Kashala
- Department of Cancer Biology, Harvard School of Public Health, Boston, Massachusetts 02115
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537
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Zhang H, Liu Z, Xu J, Qian X, Qiao Y, Lin C, Xu K. Anomalous anisotropy of fission fragments in near- and sub-barrier complete fusion-fission reactions of 16O+232Th, 19F+232Th, and 16O+238U. Phys Rev C Nucl Phys 1994; 49:926-931. [PMID: 9969299 DOI: 10.1103/physrevc.49.926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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538
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Peterson EM, Xu K, Holland KD, McKeon AC, Rothman SM, Ferrendelli JA, Covey DF. Alpha-spirocyclopentyl- and alpha-spirocyclopropyl-gamma-butyrolactones: conformationally constrained derivatives of anticonvulsant and convulsant alpha,alpha-disubstituted gamma-butyrolactones. J Med Chem 1994; 37:275-86. [PMID: 8295215 DOI: 10.1021/jm00028a011] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To further study the putative gamma-butyrolactone site of the GABAA/chloride channel complex, constrained derivatives of convulsant and anticonvulsant alpha,alpha-disubstituted gamma-butyrolactones (alpha-spirocyclopropyl- and alpha-spirocyclopentyl-gamma-butyrolactones) were synthesized and evaluated biologically. Most of the spirocyclopropyl agents were anticonvulsants when tested against pentylenetetrazole-induced seizures in mice. These agents effectively displaced 35[S]-tert-butylbicyclophosphorothionate (35[S]-TBPS), a ligand for the picrotoxin binding site of the GABAA/chloride channel, from rat neuronal membranes and affected the GABA-mediated current in hippocampal neurons. The monomethyl-substituted spirocyclopropyl agent with a methyl group cis to the carbonyl (15) potentiates GABA-induced current whereas the trans derivative (16) blocks the current. The only anticonvulsant in the spirocyclopentyl series was the unsubstituted spirocyclopentyl compound 2. All the other substituted spirocyclopentyl targets were inactive in vivo at the highest dose tested except for convulsant 9, which has a trans 2,5-dimethyl-substituted cyclopentyl ring. All the spirocyclopentyl derivatives displaced 35[S]-TBPS from rat neuronal membranes very effectively, and they also all potentiated GABA-induced chloride current except for convulsant 9 which blocked the current. From the data obtained in this investigation, it appears that when the volume occupied above and below the lactone ring is as large as that occupied by spirocyclopentyl agent 9, convulsant activity is observed. Groups with less volume in these areas either are inactive in the behavioral test or have anticonvulsant activity. When bound to the GABAA/chloride channel, the larger molecules may stabilize the closed state of the channel whereas the smaller molecules may stabilize the open state.
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Affiliation(s)
- E M Peterson
- Department of Molecular Biology, Washington University School of Medicine, St. Louis, Missouri 63110
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539
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Ji YH, Mansuelle P, Xu K, Granier C, Kopeyan C, Terakawa S, Rochat H. Amino acid sequence of an excitatory insect-selective toxin (BmK IT) from venom of the scorpion Buthus martensi Karsch. Sci China B 1994; 37:42-9. [PMID: 8068186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The insect-selective neurotoxin (BmK IT) of scorpion Buthus martensi Karsch was first reduced and S-alkylated, and then digested by TPCK-trypsin and Staphylococcus aureus V-8 Protease. The enzymatic peptides were purified on TLC-plastic sheet and submitted to determine their amino acid compositions and sequences. The sequence of the 70 amino acid residues of BmK IT was established with reference to the primary structure of AaH IT, another excitatory insect-selective toxin from the venom of North African scorpion Androctonus australis Hector. About 75% of the homologous sequence was found in the molecules of BmK IT and AaH IT. It is obvious that the results contribute toward better understanding of the molecular structure characteristics, structure/activity relationship of scorpion insect-selective toxins, and they can serve as the molecular basis for utilizing the toxins as a tool to clarify molecular mechanism involved in channel gating, and to infer the possibility of developing them as new selective bioinsecticides.
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Affiliation(s)
- Y H Ji
- Shanghai Institute of Physiology, Academia Sinica, PRC
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540
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Abstract
A new technology called primer extension preamplification (PEP), which has been applied to single spermatozoa, increases the amount of polymerase chain reaction (PCR) templates by amplifying DNA of the whole genome. The current investigation was aimed at applying PEP to single human blastomeres. Two blastomeres with nuclei from arrested embryos were selected for this study. Using three different PEP protocols (experiments I, II and III), DNA from single blastomeres was amplified using 15-base oligonucleotide random primers. The efficiency of the procedure was determined by further amplifications of aliquots of the PEP products with two specific sequences. Three aliquots from each PEP product were used as PCR templates for the human X chromosome (X) or the exon 10 of the cystic fibrosis gene (CF). PCR amplified products were analysed by gel electrophoresis. In experiment I, when X primers were used, positive signals were detected in all 10 embryos (100%), 90.0% (18/20) of the blastomeres, and in 80.0% (96/120) of the replicates. When CF primers were amplified, all embryos (100%, 10/10), 90.9% (18/20) of the blastomeres and 78.3% (47/60) of the replicates were positive. In experiment II, efficiency was significantly reduced when total time for the procedure was minimized from 8 h to 5 h and 45 min. Although the time was further reduced to 4 h and 40 min in experiment III, the efficiency remained the same as in experiment I when the volume of PEP was reduced from 60 microliters (experiments I and II) to 40 microliters. One out of 132 control replicates (0.8%) was contaminated.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- K Xu
- Department of Obstetrics and Gynecology, New York Hospital-Cornell University Medical College, NY 10021
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541
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Xu K, Näveri L, Frerichs KU, Hallenbeck JM, Feuerstein G, Davis JN, Sirén AL. Extracellular catecholamine levels in rat hippocampus after a selective alpha-2 adrenoceptor antagonist or a selective dopamine uptake inhibitor: evidence for dopamine release from local dopaminergic nerve terminals. J Pharmacol Exp Ther 1993; 267:211-7. [PMID: 7901393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The effect of 6-chloro-2,3,4,5-tetrahydro-3-methyl-1-H-3-benzazepine (SKF 86466), a selective nonimidazoline alpha-2 adrenoceptor antagonist, on hippocampal release of norepinephrine and dopamine in conscious rats was investigated by in vivo microdialysis and high-pressure liquid chromatography. Additionally, extracellular concentrations of hippocampal dopamine (DA) and norepinephrine (NE), during infusion of selective monoamine uptake inhibitors, were determined in freely moving rats. The basal concentration of NE in the dialysate was 4.9 +/- 0.3 pg/20 microliters. Intravenous administration of 5 or 10 mg/kg of SKF 86466 was associated with a transient increase (30 min) of 2-fold (12 +/- 1 pg/20 microliters; P < .05) and 8-fold (39 +/- 3 pg/20 microliters; P < .05), respectively, in dialysate NE, whereas a 1-mg/kg dose had no effect. DA was not detected in basal dialysates, but after the administration of 5 or 10 mg/kg of SKF 86466, 3.9 +/- 0.4 and 6.4 +/- 0.6 pg/20 microliters, respectively, was present in the dialysates. The maximum increase in dialysate DA was reached 60 to 90 min after SKF 86466. The DA was not derived from plasma because plasma NE was elevated after the 5 mg/kg dose of SKF 86466 whereas no plasma DA was detected. In order to determine whether DA was present in noradrenergic nerve terminals, the dopamine beta-hydroxylase inhibitor SKF 102698 was administered (50 mg/kg i.p.). The inhibitor decreased dialysate NE but DA was still not detected in the dialysate.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- K Xu
- Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, Maryland
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542
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Zhang J, Sun W, Zhao H, Bian S, Xu K, Li M, Xu Y. Enhancement of the exponential gain coefficient as a result of the light-fanning effect in thin doped LiNbO(3) crystals. Opt Lett 1993; 18:1391-1393. [PMID: 19823391 DOI: 10.1364/ol.18.001391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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543
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Abstract
The 8th step in the 10-step heme biosynthetic pathway of Salmonella typhimurium is the oxidation of coproporphyrinogen III to protoporphyrinogen IX. On the basis of genetic studies, we have suggested that this reaction may be catalyzed by either of two different enzymes, an oxygen-dependent one encoded by hemF or an oxygen-independent enzyme encoded by hemN. Here, we report the cloning of the S. typhimurium hemF gene and its DNA sequence. The predicted amino acid sequence of the HemF protein is 44% identical to that of the coproporphyrinogen oxidase encoded by the yeast HEM13 gene. The wild-type S. typhimurium strain LT-2 produces an oxygen-dependent coproporphyrinogen oxidase activity detectable in crude extracts, which is not found in hemF mutants and is overproduced in strains carrying the hemF gene on a multicopy plasmid. the hemF gene is the second gene in an operon with an upstream gene with an unknown function, whose amino acid sequence suggests a relation to amidases involved in cell wall synthesis or remodeling. The upstream gene and hemF are cotranscribed from a promoter which was mapped by primer extension. A weaker, hemF-specific promoter is inferred from the behavior of an omega-Cm insertion mutation in the upstream gene. Although this insertion decreases expression of beta-galactosidase about 7.5-fold when placed upstream of a hemF-lacZ operon fusion, it still allows sufficient HemF expression from an otherwise wild-type construct to confer a Hem+ phenotype. The hemF operon is transcribed clockwise with respect to the genetic map.
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Affiliation(s)
- K Xu
- Department of Microbiology, University of Alabama, Birmingham 35294
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544
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Xu K, Chen W. [Grafting of autogenous jugular vein and glutaraldehyde-stabilized human umbilical vein in dogs]. Zhonghua Yi Xue Za Zhi 1993; 73:413-5, 447. [PMID: 8293344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The glutaraldehyde-stabilized human umbilical cord vein (HUV) was implanted to the intrarenal aorta in dogs, by using autogenous jugular vein (AJV) as control. The healing mechanism was shown by angiography, radioisotope scanning Doppler ultrasound, LM, SEM and TEM. The patency rate in 6 months was 95.2% in AJV and 87.5% in HUV. No significant difference was noted between the two veins (P > 0.05). Pathohistological study of AJV and HUV after implantation showed that there were three stages: acute injury, acute inflammatory reaction and hyperplastic repairing of tissues. The new endothelial cells of AJV grew earlier and faster than those of HUV. But, both veins were endothelialized 6 months after operation. The subendothelium of new intima consisted of fibroblasts and collagen fibres less myointimal cells derived from smooth muscle cells in the media. The media and the adventilized were replaced by fibrous connective tissue. HUV stabilized with 0.5% glutaraldehyde for grafting caused no immunologic rejection, and had the structure of the venous wall and antithrombotic function, keeping the grafts patent.
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Affiliation(s)
- K Xu
- Department of Applied Anatomy and Surgery, Third Military Medical University, Chongqing
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545
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Cho SN, Gormus BJ, Xu K, Bohm RP, Walsh GP, Meyers WM, Kim JD. Serologic responses to nerve antigens in sooty mangabey monkeys with experimental leprosy. Int J Lepr Other Mycobact Dis 1993; 61:236-44. [PMID: 8371033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Eight sooty mangabey monkeys were inoculated intravenously and intradermally with varying doses of Mycobacterium leprae from 4.8 x 10(7) to 4.8 x 10(10). Serum samples were obtained from the animals at intervals of about 3 months for 90 months, and were examined for IgM and IgG antibodies to nerve antigens, including ceramide, galactocerebroside (GC), and asialo-GM1 (AGM1), using an enzyme-linked immunosorbent assay (ELISA). The serological results were then compared with clinical findings, particularly nerve involvement. Of 8 mangabey monkeys inoculated with M. leprae, 7 animals had clinical leprosy; 6 of them had nerve damage, including neurologic deformities in 4 monkeys and nerve enlargement in 2. Median time for the initial signs of leprosy was 10 months postinoculation (p.i.), a range from 4 to 35 months. In contrast, nerve damage was noted rather late, about 35 to 86 months p.i. (median 54 months). The major immunoglobulin class to ceramide, GC, and AGM1 antigens was IgM, and the antibody responses to the nerve antigens appeared from 15 to 63 months p.i. (median 37 months). Antineural antibodies were thus detectable about 18 months (range -2 to 60 months) prior to observable nerve damage. In addition, elevation of antineural antibody levels were predictive of clinical exacerbation of the disease and neuritic damage. This study suggests that antineural antibodies are produced during the course of M. leprae infection and may be indicative of nerve damage, such as neurological deformities or nerve enlargement, in leprosy patients.
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Affiliation(s)
- S N Cho
- Department of Microbiology, Yonsei University College of Medicine, Seoul, Republic of Korea
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546
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Bian S, Zhang J, Su X, Xu K, Sun W, Jiang Q, Chen H, Sun D. Self-pumped phase conjugation of 18 degrees -cut Ce-doped KNSBN crystal at 632.8 nm. Opt Lett 1993; 18:769-771. [PMID: 19802267 DOI: 10.1364/ol.18.000769] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the self-pumped phase conjugation of an 18 degrees -cut Ce-doped (K(y)Na(1-y))(2m)(Sr(x)Ba(1-x))(1-m) Nb(2)O(6) crystal at a 632.8-nm He-Ne laser wavelength. A maximum phase-conjugation reflectivity of 84.3% has been measured. In addition, its incident angular response and time response are measured.
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547
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Zhang J, Xu H, Yuan Y, Xu K. Real-time coherent image differentiation using a self-pumped phase conjugator with Cu:KNSBN. Appl Opt 1993; 32:1470-1472. [PMID: 20820278 DOI: 10.1364/ao.32.001470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A technique for real-time coherent image differentiation is described in a device consisting of a self-pumped phase conjugator that uses a copper-doped potassium sodium strontium barium niobate crystal. We demonstrate the proposed technique.
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548
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Liu H, Yang S, Xu K, Li H, Tan J. [Nilestriol prevents osteoporosis in ovariectomized rats]. Hua Xi Yi Ke Da Xue Xue Bao 1993; 24:40-4. [PMID: 8340090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In order to determine the effects and mechanism of Nilestriol upon bone metabolism, 4-month aged female SD rats were divided randomly into three groups: The OVX group subjected to bilateral ovariectomy, the SHAM group to sham operation, the Nilestriol (CEE3) group to bilateral ovariectomy and treated with CEE3 0.15 mg/100 g BW once a week for 10 weeks. The CEE3 was introduced directly into the stomach from the first day after operation. All rats were killed 10 weeks after operation and their right proximal tibiae were processed undercalcified for quantitative bone histomorphometry. The weights of bone and inorganic matter (ash content) and content of calcium, phosphorus of right humeral were measured. The results showed that in the OVX group the trabecular bone volume, the trabecular thickness, the content of calcium bone, and the ratios of bone weight and ash weight to body weight were all significantly reduced. The bone loss was associated with an increase in bone remodeling; the bone resorption appeared much more marked than the bone formation. In contrast, the ovariectomized animals treated with CEE3 had normalization of bone mass and a declined index of bone resorption and formation which recovered the balance of bone remodeling. It suggested that CEE3 is successful in prevention of bone loss in OVX rats. It is convinced of using Nilestriol to prevent postmenopausal osteoporosis.
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549
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Abstract
Two transposable elements, IS5376 and IS5377, were identified in the thermophile Bacillus stearothermophilus CU21 based upon the following criteria: (1) both were found to appear on different plasmids introduced into the same host CU21; (2) signals of homology were found between the genomic DNA of CU21 and each of them; (3) different numbers of Southern hybridization bands were found for the genomic DNA of different strains of B. stearothermophilus; and (4) characteristic inverted repeats at both ends and direct repeats of the target DNA adjacent to them were found for both IS5376 and IS5377. Two open reading frames (ORFs) were detected for IS5376 and one for IS5377. The putative coding products of the ORFs are homologous to those of known ISs from mesophiles and are considered to be transposases. The results of analyses of nucleotide sequence and the deduced amino acid sequence suggest that IS5376 is a member of the IS21 family and that IS5377 is a member of the IS4 family.
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Affiliation(s)
- K Xu
- Institute of Genetics, Fudan University, Shanghai, China
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550
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Takahashi M, Okawada T, Kato R, Mochizuki T, Ohkawa Y, Kaneko M, Xu K, Zhang HG, He FX. [Transjugular intrahepatic portosystemic stent shunt (TIPSS) with use of Rösch-Uchida transjugular liver access set--evaluation by CT and its clinical application]. Nihon Igaku Hoshasen Gakkai Zasshi 1992; 52:1692-4. [PMID: 1488300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Appropriateness of the Rösch-Uchida transjugular liver access set designed for TIPSS procedure was confirmed, especially about the catheter angle and effective length of the 20 G puncture needle, by CT analysis on three dimensional vascular anatomy of the liver. Clinically, TIPSS using the set was successfully made for two patients, connecting superior right hepatic vein with right portal vein in one patient and middle hepatic vein with left portal vein in another patient with hypoplastic right portal vein. Prior to TIPSS procedure, verification of vascular anatomy on CT images is the key to success of TIPSS in safe.
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Affiliation(s)
- M Takahashi
- Department of Radiology, Hamamatsu University School of Medicine
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