251
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Zhang KJ, Zhang YX. [Recent advances in experimental and clinical study on ligustrazine in treating respiratory disease]. Zhongguo Zhong Xi Yi Jie He Za Zhi 1995; 15:638-40. [PMID: 8704434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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252
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Zhang YX, Yamashita H, Ohshita T, Sawamoto N, Nakamura S. ATP increases extracellular dopamine level through stimulation of P2Y purinoceptors in the rat striatum. Brain Res 1995; 691:205-12. [PMID: 8590054 DOI: 10.1016/0006-8993(95)00676-h] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.1] [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: 01/31/2023]
Abstract
The effect of ATP on release of dopamine (DA) from rat striatum was studied using in vivo microdialysis. ATP increased the striatal extracellular levels of DA dose-dependently. These analogs produced an increase in DA according to this order of potency: 2-methylthio ATP > ATP > or = alpha,beta-methylene ATP > ADP > AMP > adenosine. Adenosine 5'-[beta, gamma imido]-triphosphate had a more prolonged effect on the increase in DA level than ATP. The ATP-induced increase in DA was inhibited by adding suramin, a nonselective P2 purinoceptor antagonist, and reactive blue 2, a P2Y purinoceptor antagonist, but not inhibited by xanthine amine congener, an adenosine receptor antagonist. Pertussis toxin reduced the increase in DA produced by ATP, which suggests that the P2 purinoceptor may be coupled with a G-protein in the rat striatum. Results suggest that P2Y purinoceptors may involve an ATP-induced increase in DA. The ATP-induced release of DA was tetrodotoxin-sensitive, Ca(2+)-dependent and was abolished by omega-conotoxin GVIA, indicating that the opening of voltage-sensitive Na+ channel and the Ca2+ influx through the N-type voltage-dependent calcium channel are both required for the ATP-induced increase in DA. The ATP-induced increase in DA is presumably due to the release of DA via the stimulation of P2Y purinoceptors in the rat striatum.
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Affiliation(s)
- Y X Zhang
- Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan
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253
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Gao ZR, Zhang YX, Hu J, Xu WD. Quantitative analysis of the tomographic technetium-99m MIBI (99mTc-MIBI) myocardial bullseye display: application to diagnosis of coronary artery disease. J Tongji Med Univ 1995; 15:65-7. [PMID: 8731954 DOI: 10.1007/bf02887903] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In this study, the 99mTc-MIBI myocardial bullseye display of 31 healthy persons and 34 patients with myocardial ischemia and 17 patients with myocardial infarction were analyzed quantitatively; and compared with the results of myocardial tomography analysis and qualitative bullseye analysis. The sensitivities of the three methods were 88.2%, 91.2% and 94.1% respectively (P > 0.05), and the specificities were 93.5%, 83.9% and 83.9% respectively (P < 0.05). On the other hand, the quantitative analysis obviously outperformed the other two methods in the detection of ischemic segments of myocardium near infarction zone (P < 0.01). The quantitative analysis of 99mTc-MIBI myocardial bullseye (quantitative bullseye) was an objective, specific and sensitive method for diagnosis of coronary artery disease.
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Affiliation(s)
- Z R Gao
- Department of Nuclear Medicine, Xiehe Hospital, Tongji Medical University, Wuhan
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254
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Gentzbittel L, Vear F, Zhang YX, Bervillé A, Nicolas P. Development of a consensus linkage RFLP map of cultivated sunflower (Helianthus annuus L.). Theor Appl Genet 1995; 90:1079-86. [PMID: 24173066 DOI: 10.1007/bf00222925] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/1994] [Accepted: 11/22/1994] [Indexed: 05/04/2023]
Abstract
This paper provides the first description of a consensus map of the cultivated sunflower genome (Helianthus annuus L., n=17 chromosomes), based on RFLP. A total of 180 probe-enzyme combinations were mapped on at least one of five segregating progenies (three F2 and two BC1 populations), revealing 237 loci that did not show any distortion of segregation. The consensus linkage map obtained with these loci covers 1150 cM and consists of 16 linkage groups of more than 20 cM, 7 groups of less than 20 cM and 18 unlinked loci. The mean distance between loci is 7 cM, but in some regions intervals of 20 cM remain. Genotypic and gametic segregation distortions affect about 7% of loci. It was found that 25% of the probes mapped using several different restriction enzymes or that on different progenies they revealed 2 or more loci.
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Affiliation(s)
- L Gentzbittel
- G.I.E. Cartisol, 12 avenue George V, 75008, Paris, France
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255
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Yamashita H, Kawakami H, Zhang YX, Hagiwara T, Tanaka K, Nakamura S. Inhibition by folded isomers of L-2-(carboxycyclopropyl)glycine of glutamate uptake via the human glutamate transporter hGluT-1. Eur J Pharmacol 1995; 289:387-90. [PMID: 7621914 DOI: 10.1016/0922-4106(95)90118-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [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: 01/26/2023]
Abstract
The effects of isomers of 2-(carboxycyclopropyl)glycine (CCG) on uptake of L-glutamate were investigated in COS-7 cells that expressed a cloned human glutamate transporter (hGluT-1). The (2S, 3S, 4R)-isomer (L-CCG-III) and the (2S, 3R, 4S)-isomer (L-CCG-IV) markedly inhibited glutamate uptake with a 50% inhibitory concentration of 290 nM and 1.1 microM, respectively. The (2S, 3S, 4S)-isomer (L-CCG-I) and the (2S, 3R, 4R)-isomer (L-CCG-II) did not inhibit glutamate uptake at concentrations of < or = 10 microM. Thus, hGluT-1 showed a markedly higher affinity for L-CCG-III and L-CCG-IV with a folded conformation of the glutamate skeleton, than for L-CCG-I or L-CCG-II with an extended conformation.
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Affiliation(s)
- H Yamashita
- Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan
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256
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Liu ZG, Zhao SL, Zhang YX. [Cost-benefit analysis on immunization of newborns with hepatitis B vaccine in Jinan City]. Zhonghua Liu Xing Bing Xue Za Zhi 1995; 16:81-4. [PMID: 7781052] [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
The decision tree model cost-benefit analysis method was used to analyse the strategies and economic benefits of immunization of newborns with hepatitis B vaccines in Jinan City. The results showed that all the three vaccination strategies could all produce positive benefits. Their BCR were 42.41 to 48.01. Through the decision analysis, it concluded that stress should be laid on the blocking of mother-to-infant transmission, and that if there are sufficient HB vaccines, all newborns should be vaccinated. In addition, the results of sensitivity analysis indicate that the benefits of HB vaccination are outstanding and quite stable.
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Affiliation(s)
- Z G Liu
- Shandong Provincial Hygiene and Epidemic Prevention Station, Jinan
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257
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Wang ZM, Zhang YX, Wu K, Yuan MH, Chen WX, Qin GG. Effects of hydrogen on Er/p-type Si Schottky-barrier diodes. Phys Rev B Condens Matter 1995; 51:7878-7881. [PMID: 9977375 DOI: 10.1103/physrevb.51.7878] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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258
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Tanaka M, Zhang YX, Ishida H, Akasaka T, Sato K, Hayakawa I. Mechanisms of 4-quinolone resistance in quinolone-resistant and methicillin-resistant Staphylococcus aureus isolates from Japan and China. J Med Microbiol 1995; 42:214-9. [PMID: 7884804 DOI: 10.1099/00222615-42-3-214] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [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: 01/27/2023] Open
Abstract
Ninety-two and 33 methicillin-resistant Staphylococcus aureus (MRSA) strains were isolated in Japan and China respectively. They were categorised as ofloxacin-susceptible (MIC < 12.5 mg/L), moderately (MIC 12.5-25 mg/L) or highly (MIC > or = 50 mg/L) ofloxacin-resistant. 4-Quinolone concentrations required to inhibit purified DNA gyrase from the moderately and highly quinolone-resistant MRSA were at least 20 times higher than those required to inhibit the equivalent enzyme from quinolone-susceptible strains. Reconstitution assays demonstrated that the 4-quinolone-resistant MRSA had a mutation in subunit A of DNA gyrase. A portion of the gyrA gene from amino acids codons 40-115 was sequenced. Four moderately resistant and seven highly resistant MRSA contained a Ser-->Leu substitution at amino acid 84; one moderately and one highly resistant MRSA and one moderately resistant methicillin-susceptible S. aureus (MSSA) strain contained a Glu-->Lys substitution at amino acid 88. Eight MRSA, including one quinolone-susceptible strain and one MSSA contained a silent mutation at amino acid 86. Uptake of ofloxacin in moderately resistant strains was almost the same in the presence or absence of carbonyl cyanide m-chlorophenylhydrazone (CCCP), whereas in highly resistant strains, uptake increased when CCCP was added. Restriction fragment length analysis of the norA gene with the restriction endonuclease SfcI showed a mutation of nucleotide position 1085 in all MRSA strains tested except for one highly quinolone-resistant strain. Thus the mechanisms of 4-quinolone-resistance in these MRSA isolates involved alterations in both DNA gyrase and antimicrobial uptake and efflux.
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Affiliation(s)
- M Tanaka
- Exploratory Research Laboratories 1, Daiichi Pharmaceutical Co. Ltd, Tokyo, Japan
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259
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Yamashita H, Kitayama S, Zhang YX, Takahashi T, Dohi T, Nakamura S. Effect of nicotine on dopamine uptake in COS cells possessing the rat dopamine transporter and in PC12 cells. Biochem Pharmacol 1995; 49:742-5. [PMID: 7887991 DOI: 10.1016/0006-2952(94)00422-i] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [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: 01/27/2023]
Abstract
The effect of nicotine on the uptake of dopamine (DA) is not completely understood. We studied its effect on PC12 cells and on COS cells transfected with the rat DA transporter cDNA (pcDNADAT1). DA uptake by PC12 cells was inhibited by nicotine in a concentration-related fashion. Treatment of PC12 cells with nerve growth factor (NGF) increased such inhibition. This inhibitory effect was abolished by hexamethonium and mecamylamine, indicating that nicotine acted via the nicotinic acetylcholine (nACh) receptors in PC12 cells. This view is also supported by evidence that acetylcholine (ACh) reduced the uptake of DA in a hexamethonium-, but not atropine-, sensitive fashion. However, nicotine failed to inhibit DA uptake by COS cells possessing the DA transporter. These results suggest that the inhibitory effect of nicotine on DA uptake, when coupled with an nACh receptor leading to an indirect action on the transporter, may play a role in regulating extracellular concentrations of DA.
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Affiliation(s)
- H Yamashita
- Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan
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260
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Song HY, Dunbar JD, Zhang YX, Guo D, Donner DB. Identification of a protein with homology to hsp90 that binds the type 1 tumor necrosis factor receptor. J Biol Chem 1995; 270:3574-81. [PMID: 7876093] [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 yeast-based two hybrid has been used to identify a novel protein that binds to the intracellular domain of the type 1 receptor for tumor necrosis factor (TNFR-1IC). The TNF receptor-associated protein, TRAP-1, shows strong homology to members of the 90-kDa family of heat shock proteins. After in vitro transcription/translation and 35S labeling, TRAP-1 was precipitated using a fusion protein consisting of glutathione S-transferase and TNFR-1IC, showing that the two proteins directly interact. The ability of deletion mutants of TNFR-1 to interact with TRAP-1 was tested using the two hybrid system. This showed that the amino acid sequences that mediate binding are diffusely distributed outside of the domain in the C terminus of TNFR-1IC that signals cytotoxicity. The 2.4-kilobase TRAP-1 mRNA was variably expressed in skeletal muscle, liver, heart, brain, kidney, pancreas, lung, and placenta. TRAP-1 mRNA was also detected in each of eight different transformed cell lines. Identification of TRAP-1 may be an important step toward defining how TNFR-1, which does not contain protein tyrosine kinase activity, transmits its message to signal transduction pathways.
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Affiliation(s)
- H Y Song
- Department of Physiology and Biophysics, Indiana University School of Medicine, Indianapolis 46202
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261
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Zhang YX, Wang YQ, Wu YL, Zhu DM. Uptake of ciprofloxacin in methicillin-resistant Staphylococcus aureus. Drugs 1995; 49 Suppl 2:192-3. [PMID: 8549300 DOI: 10.2165/00003495-199500492-00038] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Y X Zhang
- Institute of Antibiotics, Hua Shan Hospital, Shanghai Medical University, China
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262
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Shen JY, Ding TY, Zhang YX, Mu GG. Real-time pattern recognition system based on a bipolar winner-take-all model with a threshold. Opt Lett 1994; 19:2158-2160. [PMID: 19855772 DOI: 10.1364/ol.19.002158] [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: 05/28/2023]
Abstract
A threshold is added to recognize an input pattern that has too few similarities to be one of the memory patterns. A real-time pattern recognition system based on the improved model is given. The unipolar optical pattern recognition system has all the characteristics of a fully bipolar winner-take-all model and has illumination invariance. A liquid-crystal spatial light modulator is used as a real-time input device, and a mask and a lens array perform the threshold and weighted sums of the input pattern. Some experimental results are also shown.
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263
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Zhang YX, Zhi N, Yu SR, Li QJ, Yu GQ, Zhang X. Protective immunity induced by 67 K outer membrane protein of phase I Coxiella burnetii in mice and guinea pigs. Acta Virol 1994; 38:327-32. [PMID: 7793356] [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]
Abstract
A 67 K outer membrane protein (OMP) isolated from phase I Coxiella burnetii QiYi strain was purified with monoclonal antibodies (MoAb) coupled to CNBr-Sepharose 4B. Chemical analyses of the 67 K protein showed that it contained seventeen kinds of amino acids and no LPS. The immunogenicity and protectivity of the 67 K protein against C. burnetii was evaluated in mice and guinea pigs by in vitro lymphocyte proliferation assay, delayed-type skin test, antibody conversion rate, and immunization and challenge tests. Intraperitoneal injection of the 67 K protein resulted in antibody production against phase I and II whole cell antigens. The anti-67 K antibody conversion rate was found to be 100% in mice and guinea pigs as well. Lymphocytes were responses in vitro to specific antigen. In addition, delayed-type hypersensitivity appeared two weeks after immunization with the 67 K protein. Moreover, 100% of mice and guinea pigs inoculated with the 67 K protein were protected against a challenge with 10(3) ID50 virulent C. burnetii. In conclusion, these results demonstrate that the 67 K OMP elicits in vivo and in vitro both B cell-mediated and T cell-mediated immunity in mice and guinea pigs. Thus the 67 K protein is a candidate for an effective subunit vaccine against Q fever.
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Affiliation(s)
- Y X Zhang
- Department of Microbiology, Third Military Medical College, Sichuan Province, People's Republic of China
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264
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Gentzbittel L, Zhang YX, Vear F, Griveau B, Nicolas P. RFLP studies of genetic relationships among inbred lines of the cultivated sunflower, Helianthus annuus L.: evidence for distinct restorer and maintainer germplasm pools. Theor Appl Genet 1994; 89:419-25. [PMID: 24177890 DOI: 10.1007/bf00225376] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/1993] [Accepted: 02/02/1994] [Indexed: 05/13/2023]
Abstract
One-hundred-and-eighty-one nuclear DNA probes were used to examine restriction-fragment length polymorphism in inbred lines of the cultivated sunflower (Helianthus annuus L.). The probes were from six libraries: two genomic libraries - one made with PstI and the other with HindIII, and four cDNA libraries - from etiolated plantlets, green leaves, ovaries, petals and anthers. Total DNA from 17 inbred lines representing an overview of the genetic stocks of sunflower, including restorer and maintainer lines of the classical cytoplasmic male sterility, was digested with four different restriction enzymes and probed in 331 probe-enzyme combinations. Of 181 clones analysed, 73 probes were found to be polymorphic. Genetic distances between inbreds were calculated from the resultant proportion of shared bands and submitted to principal component analysis and the UPGMA 'tree-making' method. The RFLP analysis allowed a clear differentiation between restorer and maintainer lines of the cytoplasmic male sterility, together with a grouping of some of the genotypes from the same origin. The analysis of the accuracy of distance estimation as a function of the number of probe-enzyme combinations used, indicates that 40-50 combinations ensure a confidence level of near 95%. Considering the inbreds as representatives of the range of cultivated inbreds, estimates of gene diversity, as well as estimates of average gene diversity between and within the sets of restorer and maintainer lines, were calculated. Estimation of gene diversity showed that the available genetic variability in cultivated sunflower, based on allelic frequencies, is lower than that of other plants (H=0.20). Moreover, we show that the proportion of genetic variability due to the difference between maintainer and restorer lines (Dm) is about 2%.
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Affiliation(s)
- L Gentzbittel
- GIE CARTISOL, 4 rue Ledru, 01, Clermont-Ferrand Cedex, France
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265
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Tang L, Zhang YX, Hutchinson CR. Amino acid catabolism and antibiotic synthesis: valine is a source of precursors for macrolide biosynthesis in Streptomyces ambofaciens and Streptomyces fradiae. J Bacteriol 1994; 176:6107-19. [PMID: 7928973 PMCID: PMC196831 DOI: 10.1128/jb.176.19.6107-6119.1994] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [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
Targeted inactivation of the valine (branched-chain amino acid) dehydrogenase gene (vdh) was used to study the role of valine catabolism in the production of tylosin in Streptomyces fradiae and spiramycin in Streptomyces ambofaciens. The deduced products of the vdh genes, cloned and sequenced from S. fradiae C373.1 and S. ambofaciens ATCC 15154, are approximately 80% identical over all 363 amino acids and 96% identical over a span of the first N-terminal 107 amino acids, respectively, to the deduced product of the Streptomyces coelicolor vdh gene. The organization of the regions flanking the vdh genes is the same in all three species. Inactivation of the genomic copy of the vdh gene in S. fradiae and S. ambofaciens by insertion of a hygromycin resistance (hyg) gene caused loss of the valine dehydrogenase (Vdh) activity, and thus only one enzyme is responsible for the Vdh activity in these organisms. Analysis of the culture broth by bioassay revealed that the vdh::hyg mutants produce an approximately sixfold-lower level of tylosin and an approximately fourfold-lower level of spiramycin than the wild-type S. fradiae and S. ambofaciens strains, while maintaining essentially identical growth in a defined minimal medium with either 25 mM ammonium ion or 0.05% asparagine as the nitrogen source. The addition of the valine catabolite, propionate or isobutyrate, and introduction of the wild-type vdh gene back to each vdh::hyg mutant reversed the negative effect of the vdh::hyg mutation on spiramycin and tylosin production. These data show that the catabolism of valine is a major source of fatty acid precursors for macrolide biosynthesis under defined growth conditions and imply that amino acid catabolism is a vital source of certain antibiotic precursors in actinomycetes.
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Affiliation(s)
- L Tang
- School of Pharmacy, University of Wisconsin, Madison 53706
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266
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Wang DX, Tai JW, Zhang YX. Two-dimensional optical wavelet transform in space domain and its performance analysis. Appl Opt 1994; 33:5271-5274. [PMID: 20935915 DOI: 10.1364/ao.33.005271] [Citation(s) in RCA: 2] [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: 05/30/2023]
Abstract
A new architecture of an optical wavelet transform system with a lenslet array is proposed, and its optical performance and optical limits are analyzed.
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267
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Abstract
Macrolide and polyether biosynthesis in actinomycetes is regulated at the level of precursor supply by effects of nutrients on the sources of the low-molecular-weight fatty acids used to build the carbon framework of these antibiotics. Ammonium ion appears to suppress the first enzymes of valine and threonine catabolism and also inhibits their activity. Disruption of the valine dehydrogenase (vdh) gene of Streptomyces coelicolor destroys its ability to grow on branched-chain amino acids as the sole nitrogen source in a minimal medium but has no effect on the biosynthesis of the acetate-derived antibiotic, actinorhodin. Expression of the vdh gene is repressed by > 25 mM ammonium ion or glucose but not by valine, glycerol, or maltose. Vdh enzyme activity is stimulated by valine induction. These results suggest that the inhibition of valine catabolism by ammonium and/or glucose could explain why macrolide production is inhibited by ammonium ion.
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Affiliation(s)
- L Tang
- School of Pharmacy, University of Wisconsin, Madison 53706
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268
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Abstract
The co-transcribed structural genes, groES and groEL, of the groE stress response operon from Chlamydia trachomatis mouse pneumonitis (MoPn), were cloned and sequenced. The calculated molecular masses of the encoded heat-shock proteins (Hsp), a small Hsp (GroES) and Hsp60 (GroEL), are 11,089 and 58,367 Da, respectively. By comparison with other known chlamydial groES and groEL sequences, there is 89 and 94% nucleotide (nt) identity with C. trachomatis human strains (serovars A and L2), 77 and 82% with C. psittaci strain GPIC, and 75 and 80% with C. pneumoniae isolate AR-39. At the amino-acid level, the MoPn Hsp60 shows a 99% identity with those from C. trachomatis human strains. In a mouse model, MoPn Hsp60 could prove useful in deciphering the pathogenesis of human chlamydial diseases.
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Affiliation(s)
- Y Ho
- Maxwell Finland Laboratory for Infectious Diseases, Boston City Hospital, Boston University School of Medicine, MA 02118
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269
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Zhu ZH, An R, Zhang YX, Gong PL, Chen H, Zen FD. Effects of captopril and nadolol on renal hemodynamics in patients with essential hypertension. J Tongji Med Univ 1994; 14:45-8. [PMID: 7877194 DOI: 10.1007/bf02888058] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The randomized single-blind study was designed to compare the effects of captopril (Cap) and nadolol (Nad) on renal hemodynamics in 60 patients with essential hypertension. They were divided into two groups at random. Cap was given in dosage of 37.5-75 mg/d per os and Nad 40-80 mg/d. The results show that both drugs increase the blood volume distributed to the kidneys from cardiac output (renal blood flow/cardiac output), Cap increasing 10% (P < 0.05) and Nad 8% (P < 0.05). Renal vascular resistance (RVR) is lowered by the two drugs, 13% (P < 0.05) by Cap and 11% (P < 0.05) by Nad. These suggest that both drugs facilitate the maintenance of renal blood circulation in patients with essential hypertension, being beneficial for long-term treatment of hypertension.
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Affiliation(s)
- Z H Zhu
- Department of Nephrology, Xiehe Hospital, Tongji Medical University, Wuhan
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270
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Zhang YX, Shi Y, Zhou M, Petsko GA. Cloning, sequencing, and expression in Escherichia coli of the gene encoding a 45-kilodalton protein, elongation factor Tu, from Chlamydia trachomatis serovar F. J Bacteriol 1994; 176:1184-7. [PMID: 8106330 PMCID: PMC205172 DOI: 10.1128/jb.176.4.1184-1187.1994] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [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: 01/28/2023] Open
Abstract
The gene encoding a 45-kDa protein (45K) of Chlamydia trachomatis serovar F was cloned, sequenced, and overexpressed in Escherichia coli. Alignment of the deduced peptide sequence with E. coli elongation factor Tu (EF-Tu) demonstrated 69% identity. The 45K was recognized by a Chlamydia genus-specific monoclonal antibody GP-45 and cross-reacted with a monospecific polyclonal antibody to E. coli EF-Tu. Purified recombinant 45K has the capability to bind GDP, and the binding was enhanced in the presence of E. coli elongation factor Ts (EF-Ts). The GDP binding was specifically inhibited by the monoclonal antibody GP-45. These data suggest that the 45K is a chlamydial EF-Tu, and it forms a functional complex with E. coli EF-Ts protein.
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Affiliation(s)
- Y X Zhang
- Maxwell Finland Laboratory for Infectious Diseases, Boston City Hospital, Boston University School of Medicine, Massachusetts 02118
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271
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Le WP, Yan SX, Huang MQ, Zhang YX, Zhou HM. Kinetics of irreversible inhibition of yeast alcohol dehydrogenase during modification by o-phthaldehyde. Enzyme Protein 1994; 48:183-90. [PMID: 8589805 DOI: 10.1159/000474985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The kinetic theory of the substrate reaction during irreversible inhibition of enzyme activity described previously has been applied to a study on the kinetics of the course of inactivation of yeast alcohol dehydrogenase (YADH) by o-phthaldehyde (OPTA). The microscopic constants for the reaction of the inactivators with the free enzyme and with the enzyme-substrate complexes were determined. The inactivation is a monophasic pseudo-first-order reaction with OPTA. The apparent rate constant A is independent of the OPTA concentration, indicating that the inactivation is a noncomplexing inhibition. The marked protective effect of substrates on the inactivation of YADH by OPTA has been observed. This result suggests that the modification of the enzyme by OPTA may occur at the active site.
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Affiliation(s)
- W P Le
- Department of Biology, Xiamen University, People's Republic of China
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272
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Zhang YX, Fox JG, Ho Y, Zhang L, Stills HF, Smith TF. Comparison of the major outer-membrane protein (MOMP) gene of mouse pneumonitis (MoPn) and hamster SFPD strains of Chlamydia trachomatis with other Chlamydia strains. Mol Biol Evol 1993; 10:1327-42. [PMID: 8277858 DOI: 10.1093/oxfordjournals.molbev.a040079] [Citation(s) in RCA: 8] [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: 01/29/2023] Open
Abstract
Restriction fragments containing the major outer-membrane protein (MOMP) gene from two nonhuman (rodent) strains of Chlamydia trachomatis, the mouse pneumonitis (MoPn) strain and the SFPD strain isolated from hamsters with transmissible proliferative ileitis, were cloned and sequenced. The MOMP genes of both MoPn and SFPD encode an identical 22-amino acid leader peptide and mature polypeptides of 365 and 382 amino acids, respectively. Alignment of the MOMP genes of the two rodent strains revealed 91% identity. By comparison with other known chlamydial MOMP gene sequences, there was 80%-83% identity with human biovars strains of C. trachomatis, and there was 69%-70% identity with C. psittaci and C. pneumoniae strains. The main differences in these sequences were clustered into four variable domains. A minimum-length evolutionary tree was constructed on the basis of the MOMP gene variable positions by using PIMA package software. The minimum mutation distances indicated that (i) the MOMP genes of all chlamydial strains may have evolved from a common ancestor; (ii) all the strains of C. trachomatis compose one of the subtrees, and strains of C. psittaci and C. pneumoniae compose the other subtree; and (iii) in the C. trachomatis subtree, the human and the rodent strains are divided into two clusters. The branching pattern of this evolutionary tree is generally consistent with current classification based on serological, morphological, and other biological characteristics.
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Affiliation(s)
- Y X Zhang
- Maxwell Finland Laboratory for Infectious Diseases, Boston City Hospital, Boston University School of Medicine, Massachusetts
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273
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Zhang YX, Zhang YG. [Clinical investigation of erythrocyte function in patients with lung cancer]. Zhonghua Jie He He Hu Xi Za Zhi 1993; 16:278-80, 319. [PMID: 7923431] [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
With a yeast-erythrocyte-SPA rosette method, the function of erythrocyte immune adherence was determined in 49 cases of lung cancer, 20 cases of benign pulmonary diseases and 60 healthy persons. By means of simple morphologic method and pyrogallol autoxication method, the function of erythrocyte enhancing neutrophils phagocytosis and the activity of RBC-CuZnSOD were measured in some of these subjects. It was found that both the function of red cell immune adherence and the effect of erythrocyte enhancing phagocytosis in the patients with lung cancer were significantly weaker than in the cases of benign pulmonary diseases and the healthy subjects. The function of erythrocyte immune adherence tended to recover after effective surgical treatment. In comparison with the healthy persons, the activity of RBC-CuZnSOD was significantly lower in the patients with lung cancer. The mechanism and clinical significance of the changes in erythrocyte function were discussed.
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Affiliation(s)
- Y X Zhang
- Department of Medicine, Second Affiliated Hospital, Shanxi Medical College, Taiyuan
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274
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Bouvier L, Zhang YX, Lespinasse Y. Two methods of haploidization in pear, Pyrus communis L.: greenhouse seedling selection and in situ parthenogenesis induced by irradiated pollen. Theor Appl Genet 1993; 87:229-32. [PMID: 24190217 DOI: 10.1007/bf00223769] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/1993] [Accepted: 03/29/1993] [Indexed: 05/14/2023]
Abstract
Seedlings of 12 crosses involving pear varieties or hybrids were observed for the presence of haploid plants. On the basis of phenotypic characteristics, 17 plants corresponded to the haploid condition and, of these, 12 were determined by chromosome counting to be haploid (2n=x=17). In addition, and in order to induce in situ parthenogenesis, several pear varieties were pollinated with a selected clone carrying a homozygous dominant marker gene for the colour of red. This pollen had previously been irradiated with γ-rays of cobalt 60 at 0, 200, 250 and 500 Grays. The immature embryos were cultured in vitro, whereby 1 haploid and two mixoploid plants were obtained. Numerous diploid plants with the maternal phenotype were also obtained, and their genetic origin was subsequently studied by means of isozyme analysis.
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Affiliation(s)
- L Bouvier
- I.N.R.A. Centre de Recherche d'Angers, Station d'Amélioration des Espèces Fruitières et Ornementales, 49071, Beaucouze, France
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275
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Abstract
The effect of thiamin and its phosphate esters on dopamine (DA) release was examined in the rat striatum using an in vivo microdialysis. Intrastriatal administration of thiamin triphosphate (TTP) or thiamin diphosphate (TDP) induced DA release, but thiamin monophosphate (TMP) or thiamin did not show any change. In the absence of Ca2+ in the perfusate, TTP did not increase the DA release. omega-Conotoxin did not decrease the TTP-dependent DA release. These findings suggest that, in contrast to TMP and thiamin, TTP and TDP may play a specific role in DA release from nerve terminals.
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Affiliation(s)
- H Yamashita
- Third Department of Internal Medicine, Hiroshima University School of Medicine, Japan
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276
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Zhang YX, Du SC, Chen P. [Hepatitis B virus DNA in the serum of anti-HBs positive persons]. Zhonghua Nei Ke Za Zhi 1992; 31:629-32, 658-9. [PMID: 1306457] [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: 12/26/2022]
Abstract
In order to investigate the significance of HBV DNA in the serum of anti-HBs positive persons, the serum of 76 anti-HBs positive persons was studied for HBV DNA by means of polymerase chain reaction (PCR). The results showed that 21 (32.2%) out of 65 cases without hepatitis B vaccination were positive for HBV DNA detected with PCR (PCR-HBV DNA), but no one was positive for PCR-HBV DNA in 11 cases inoculated against hepatitis B. It was also found that 6 cases were positive for HBsAg-Ab immunocomplex in those positive for PCR-HBV DNA and the liver tissue in 2 of the 5 cases with liver-biopsy were positive for HBVAg determined with immunohistologic ABC method. We believed that persons, who acquired anti-HBs after HBV infection were different from those who were vaccinated, might carry HBV which come from the HBsAg-Ab immunocomplex and HBVAg positive hepatocytes. In addition, the study also proved that the PCR-HBV DNA positive rate correlated significantly with the anti-HBe and or anti-HBc positive rate and with the abnormal rate of liver function in the anti-HBs positive persons. It was suggested that persistent presence of HBV DNA in the bodies should be responsible for the persistent presence of anti-HBe and anti-HBc in the serum and also for the liver damage.
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Affiliation(s)
- Y X Zhang
- Department of Internal Medicine, General Hospital of Beijing Military District
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277
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Zhang YX. [Diagnostic significance of multinuclear giant cells in lymph node fine needle aspiration]. Zhonghua Zhong Liu Za Zhi 1992; 14:351-2. [PMID: 1291291] [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: 12/26/2022]
Abstract
Enlarged lymph nodes, commonly seen in inflammatory or tumorous conditions, is often suspected as Hodgkin's disease in cytologic diagnosis. Twenty cases originally diagnosed as Hodgkin's disease by fine needle aspiration of lymph nodes are reported. Eighteen of these 20 cases were checked by histopathology. It was found that only 3 had reached the correct diagnosis. The authors believe that by thorough understanding of the origin and characteristics of various types of multinuclear giant cells, differentiation from Hodgkin's disease is possible.
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278
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Yuan Y, Lyng K, Zhang YX, Rockey DD, Morrison RP. Monoclonal antibodies define genus-specific, species-specific, and cross-reactive epitopes of the chlamydial 60-kilodalton heat shock protein (hsp60): specific immunodetection and purification of chlamydial hsp60. Infect Immun 1992; 60:2288-96. [PMID: 1375196 PMCID: PMC257156 DOI: 10.1128/iai.60.6.2288-2296.1992] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.9] [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: 12/26/2022] Open
Abstract
Ocular and urogenital tract infections with Chlamydia trachomatis can progress to chronic inflammatory diseases that produce blindness and tubal infertility. The pathophysiology of these chronic disease conditions is thought to be immunologically mediated, and the chlamydial 60-kDa heat shock protein (hsp60) has been implicated as a major target antigen that stimulates the immunopathological response. The lack of chlamydial hsp60 antibodies and purified hsp60 has severely restricted studies to define more thoroughly the role of this protein in the immunopathogenesis of chlamydial disease. We produced a panel of antichlamydial hsp60 monoclonal antibodies (MAbs) and defined their specificities by immunoblotting against lysates of C. trachomatis, C. psittaci, and six other genera of bacteria. Three patterns of anti-hsp60 immunoreactivity were observed: chlamydial species specific, chlamydial genus specific, and cross-reactive. The epitopes recognized by these MAbs were localized within the primary amino acid sequence of hsp60 by immunoblotting against recombinant amino-terminal truncated hsp60 fusion polypeptides and then precisely mapped by use of overlapping synthetic peptides. The majority of the MAbs mapped to either the amino or the carboxyl termini of hsp60. Epitopes defining all three MAb reactivities mapped within amino-terminal residues 6 to 16. Genus-specific hsp60 MAbs mapped to epitopes located within this region and to residues 17 to 28 and 177 to 189. Antichlamydial hsp60 MAbs stained inclusions as effectively as MAbs specific for the major outer membrane protein. Homogeneous preparations of full-length recombinant chlamydial hsp60 and amino-terminal truncated recombinant hsp60 polypeptides were obtained by immunoabsorption chromatography with an hsp60 MAb reactive to the carboxyl terminus of the protein. Thus, the antichlamydial MAbs described here should be extremely useful for the specific immunodetection of hsp60 in tissues from individuals having different disease manifestations and for the purification of hsp60 or truncated hsp60 polypeptides for use in serologic and lymphocyte proliferation assays. The availability of these MAbs will facilitate studies to define more precisely the role of hsp60 in the immunopathogenesis of chlamydial disease.
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Affiliation(s)
- Y Yuan
- Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840
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279
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Abstract
A new approach to learning in a multilayer neural network based on a backpropagation algorithm is presented. With a sine-type thresholding function the model is more efficient and able to learn nonnegative interconnections that are suitable for optical implementations.
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280
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Moro R, Gialanella G, Zhang YX, Perrone L, Di Toro R. Trace elements in full-term neonate hair. J Trace Elem Electrolytes Health Dis 1992; 6:27-31. [PMID: 1638181] [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: 12/28/2022]
Abstract
Proton Induced X-ray Emission (PIXE) was employed to measure simultaneously the concentration of 12 trace elements in the hair of 141 AGA newborn infants at term. Log-normal distributions were measured for all elements. There were no significant differences in trace elements in relation to sex, gestational age and body weight. The geometric means (mg/kg) were: Cr, 1.5 +/- 0.2; Mn, 1.5 +/- 0.1; Fe, 51 +/- 4; Ni, 1.0 +/- 0.2; Cu, 6.1 +/- 0.3; Zn, 133 +/- 3; As, 0.055 +/- 0.005; Se 0.81 +/- 0.05; Br, 1.3 +/- 0.1; Pb, 1.4 +/- 0.2; Rb, 0.22 +/- 0.03; and Sr, 1.5 +/- 0.2. Some direct and inverse partial correlations among elements were found at different levels of significance. Each element was significantly correlated with at least one other. Zinc and copper concentrations were lower compared to data in the literature. The high values of chromium and selenium concentrations were in agreement with previous findings. The manganese level was in accordance with previous data. The Zn/Cu ratio agreed very well with the data in the literature. This indicates that while concentration values may be subjected to large variations due to living conditions, correlations could be more stable and therefore offer insight on the regulatory mechanisms governing trace element metabolism in man.
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Affiliation(s)
- R Moro
- Dipartimento di Scienze Fisiche, Università di Napoli, Italy
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281
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Abstract
The in vitro activity of ME-1206, a new aminothiazolyl cephalosporin that can be orally absorbed when converted to an ester, was compared with that of other beta-lactams. ME-1206 inhibited 50% of the Enterobacteriaceae at 2 micrograms/ml, similar to cefotaxime, ceftazidime, and cefixime. It did not inhibit, MIC greater than or equal to 32 micrograms/ml, Enterobacter species or Citrobacter freundii resistant to cefotaxime and ceftazidime, and it was less active than cefotaxime and ceftazidime against Serratia marcescens. Haemophilus influenzae, Neisseria gonorrhoeae, and Moraxella catarrhalis were inhibited by less than or equal to 0.25 micrograms/ml of ME-1206 inhibited hemolytic streptococci groups A, B, C, and G, MIC90 0.06 micrograms/ml, but it did not inhibit enterococci. Pseudomonas aeruginosa and other pseudomonads were resistant to ME-1206. MICs and MBCs of ME-1206 for susceptible species were within a dilution. ME-1206 was not hydrolyzed by TEM-1 or TEM-2, but was hydrolyzed by TEM-3 and TEM-5. ME-1206 was hydrolyzed by beta-lactamases of Morganella, Proteus vulgaris, and K1 of Klebsiella oxytoca, but minimally by the P99 beta-lactamase of Enterobacter cloacae. ME-1206 is comparable in in vitro activity and beta-lactamase stability to many of the current cephalosporins.
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Affiliation(s)
- N X Chin
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York 10032
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282
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Debski TT, Kamarck TW, Jennings JR, Young LW, Eddy MJ, Zhang YX. A computerized test battery for the assessment of cardiovascular reactivity. Int J Biomed Comput 1991; 27:277-89. [PMID: 2050435 DOI: 10.1016/0020-7101(91)90068-p] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Recent evidence has suggested a possible relationship between the tendency to exhibit excessive cardiovascular reactions during psychological challenge and the risk of cardiovascular disease. Valid techniques for reliably assessing such reactions are, however, minimally available. A test battery for the assessment of cardiovascular reactivity to experimental challenge is currently being developed at the University of Pittsburgh in conjunction with the University of Miami and Duke University. An IBM-AT compatible microcomputer is being used for the concurrent collection of physiological data and presentation of the laboratory stressors. Digitized cardiovascular data being collected include EKG, Impedance Cardiogram (ICG), phonocardiogram, and a peripheral pulse wave measure. Blood pressure readings are also being collected and stored on disk. The computer presents three challenging video games, each designed to elicit cardiovascular reactions. Processing programs are being used and developed for the standardized scoring of the digitized signals. To assist in epidemiological research a mobile testing unit has been assembled for the easy administration of the test battery in varying geographical locations. The test battery being developed will increase the feasibility of epidemiological and clinical assessment of stress-induced cardiovascular responses which may substantiate a link between reactivity and cardiovascular disease.
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Affiliation(s)
- T T Debski
- University of Pittsburgh, School of Medicine, Western Psychiatric Institute and Clinic, PA 15213-2593
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283
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Abstract
Sparfloxacin, a new fluoroquinolone, inhibited the majority of members of the family Enterobacteriaceae at less than or equal to 1 microgram/ml. It was less active than ciprofloxacin but more active than ofloxacin. Against Pseudomonas aeruginosa, it was less active than ciprofloxacin but twofold more active than ofloxacin. It inhibited Staphylococcus aureus and most Streptococcus pneumoniae and Streptococcus pyogenes isolates at 0.25 micrograms/ml, whereas ciprofloxacin and ofloxacin inhibited these isolates at 2 micrograms/ml. Bacteroides fragilis was inhibited by less than or equal to 2 micrograms/ml. Sparfloxacin was less active at an acidic pH and in the presence of Mg2+. Resistance to sparfloxacin was produced by repeated exposure, although the frequency of single-step mutants was less than 10(-9).
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Affiliation(s)
- N X Chin
- Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, New York 10032
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284
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Abstract
A two-dimensional orthogonal model of optical associative memory for storage of nonnegative patterns using a single hologram is presented. Two sets of patterns after prior orthogonal processing are composed and used for hologram recording, which permits the sequential holographic recordings to be carried on spatially separated regions of the recording material. High diffraction efficiency of the hologram is achieved. Computer simulations and optical demonstrations are also given.
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285
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Abstract
Rat pheochromocytoma PC 12 cells are susceptible to the oxidative toxicity caused by H2O2, nitrofurantoin, dopamine, and xanthine/xanthine oxidase reaction. The cytotoxicities of these agents are greatly reduced by the simultaneous presence of 0.1 mM tetrahydrobiopterin (BH4), 3 units/ml horseradish peroxidase, 0.2 mM NADH, and 0.1 units/ml sheep liver dihydropteridine reductase (DHPR). Individually, BH4, NADH and DHPR have no protection against H2O2 toxicity in PC 12 cells. Peroxidase alone offers 58% of protection if cells are incubated in the medium but only 3% in Dulbecco's phosphate buffered saline. The efficiency of the BH4-mediated antioxidation system in PC 12 cells is equal to or better than ascorbic acid and catalase, depending on the source of the reactive O2 species (ROS). The reactions responsible for the BH4-antioxidation system may consist of the non-enzymatic and the peroxidase-catalyzed reduction of H2O2 to H2O by BH4 and the regeneration of BH4 by DHPR using NADH as the cofactor. The components of this defence mechanism against ROS are all normal cellular constituents and are ubiquitous in nature. This DHPR-catalyzed redox cycling of BH4 may constitute an as yet little-known antioxidation system in mammalian cells.
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Affiliation(s)
- R S Shen
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77550
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286
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Abstract
We determined the effect of the combination of rifampin and fleroxacin against Enterobacteriaceae and streptococcal species. None of the 65 isolates tested by checkerboard assay demonstrated synergy, 12% of isolates showed an additive effect; 86.7% were indifferent, and only 1 isolate showed antagonism. The mean FIC was 1.2. When using 2 and 8 micrograms/ml of rifampin, fleroxacin MICs of 285 isolates of Enterobacteriaceae, Pseudomonas aeruginosa, Haemophilus influenzae, staphylococci, streptococci, Bacteroides, and Clostridium were not increased, but synergy was not demonstrated. Time-kill studies against Escherichia coli, P. aeruginosa, Enterobacter cloacae, Staphylococcus aureus, and Enterococcus faecalis failed to show increased killing when the two agents were present at one-half the MBC. The fleroxacin-rifampin interaction is one of indifference but provides coverage for species not adequately inhibited by fleroxacin.
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Affiliation(s)
- Y X Zhang
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York
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287
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Lecuyer MP, Zhang YX, Tellier M, Lespinasse Y. In vitro pollen tube division of irradiated and non-irradiated apple pollen. ACTA ACUST UNITED AC 1991. [DOI: 10.1051/agro:19910605] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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288
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Yang CR, Meng ZD, Wang X, Li YL, Zhang YX, Zhao QP. Diarrhoea surveillance in children aged under 5 years in a rural area of Hebei Province, China. J Diarrhoeal Dis Res 1990; 8:155-9. [PMID: 2081881] [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: 12/30/2022]
Abstract
A surveillance of diarrhoeal diseases in children aged under five years was carried out from March 1986 to February 1987 in a rural area of Hebei Province, China. Using a cluster sampling method, 270 study children were selected from 30 villages to represent a population of 105,405. Parents noted episodes of diarrhoea in children on a calender using a given definition of diarrhoea. The findings were verified by trained village doctors and were recorded monthly in the county Health and Anti-epidemic Stations. Stools of diarrhoea-affected children were examined to detect causal agents of diarrhoea, once in each of four seasons of the year. Of the 270 children, 218 (80.74%) suffered from one or more than one attacks of diarrhoea with a 95% confidence interval between 75.94% and 85.54%. There was no death due to diarrhoea. The diarrhoeal incidence in children of 3-4-year age group was significantly less than that in the children of less than 3 years (p less than 0.05). In the children with diarrhoea, the number of mean episodes was 3.15 per child/year, and the total mean course of suffering was 14 days per child/year. The ratio of diarrhoeal episodes in spring, summer, autumn, and winter was about 2.5:5:2:1. July was the month of highest occurrence of diarrhoea (146; 21.28% of all episodes). The epidemiological parameters of the disease declined with the growing age of the children, and there was no gender-specific preponderance in the number of episodes. During the whole year, 21.7% of the diarrhoeal episodes were due to bacterial pathogens, 4% of the episodes were due to rotavirus, and 3.65% episodes were associated with the detection of Trichomonas hominis.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- C R Yang
- Hebei Province Health and Anti-epidemic Station; People's Republic of China
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289
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Abstract
The transcription of omp1, the gene encoding the major outer membrane protein, was studied for two strains of Chlamydia psittaci, guinea pig inclusion conjunctivitis (GPIC) and mouse pneumonitis (Mn). The transcriptional initiation sites for the omp1 of each strain were mapped by S1 nuclease and primer extension analyses. Three different sizes of omp1 transcripts were observed for GPIC and four were observed for Mn. The production of these transcripts appeared to be the consequence of multiple tandem promoters. The order in which the omp1 RNA transcripts appeared during the growth cycle of the C. psittaci strains was found to differ from that of C. trachomatis.
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Affiliation(s)
- Y Yuan
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840
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290
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Su H, Watkins NG, Zhang YX, Caldwell HD. Chlamydia trachomatis-host cell interactions: role of the chlamydial major outer membrane protein as an adhesin. Infect Immun 1990; 58:1017-25. [PMID: 2318528 PMCID: PMC258576 DOI: 10.1128/iai.58.4.1017-1025.1990] [Citation(s) in RCA: 159] [Impact Index Per Article: 4.7] [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: 12/31/2022] Open
Abstract
The major outer membrane protein (MOMP) of Chlamydia trachomatis is characterized by four symmetrically spaced variable domains (VDs I to IV) whose sequences vary among serotypes. The surface-exposed portions of these VDs contain contiguous sequences that are both serotyping determinants and in vivo target sites for neutralizing antibodies. Previous studies using surface proteolysis of C. trachomatis B implicated VDs II and IV of the MOMP of this serotype in the attachment of chlamydiae to host cells. In this study, we used monoclonal antibodies (MAbs) specific to antigenic determinants located in VDs II and IV of the MOMP of serotype B to further investigate the role of the MOMP in the attachment of chlamydiae to host cells. MABs specific to serotype- and subspecies-specific epitopes located in exposed VDs II and IV, respectively, neutralized chlamydial infectivity for hamster kidney cells by blocking chlamydial attachment. We radioiodinated these MAbs and used them to determine the number and topology of the surface-exposed VDs II and IV epitopes on chlamydial elementary bodies. VDs II and IV each comprised approximately 2.86 x 10(4) negatively charged sites and were in proximity on the chlamydial cell surface. These studies suggest that the MAbs blocked chlamydial attachment by inhibiting electrostatic interactions with host cells. We examined the effects of thermal inactivation on both chlamydial attachment and conformation of the MOMP. Heat-inactivated chlamydiae failed to attach to host cells and exhibited a conformational change in an inaccessible invariant hydrophobic nonapeptide sequence located within VD IV of the MOMPs of C. trachomatis serotypes. These findings suggest that in addition to electrostatic interactions, a common hydrophobic component of the MOMP also contributes to the binding of chlamydiae to host cells. Thus, we propose that the MOMP functions as a chlamydial adhesin by promoting nonspecific (electrostatic and hydrophobic) interactions with host cells. Surface-accessible negatively charged VDs appear to be important in electrostatic binding, while the invariant region of VD IV may provide a subsurface hydrophobic depression which further promotes binding of chlamydiae to host cells through hydrophobic interactions.
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Affiliation(s)
- H Su
- Laboratory of Microbial Structure and Function, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840
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291
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Zhang YX, Morrison SG, Caldwell HD. The nucleotide sequence of major outer membrane protein gene of Chlamydia trachomatis serovar F. Nucleic Acids Res 1990; 18:1061. [PMID: 2315025 PMCID: PMC330378 DOI: 10.1093/nar/18.4.1061] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Y X Zhang
- National Institute of Allergy and Infectious Diseases, Laboratory of Microbial Structure and Function, Hamilton, MT 59840
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292
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Zhang YX. [Effective measures to control air pollution from burning coal]. Zhonghua Yu Fang Yi Xue Za Zhi 1990; 24:13-5. [PMID: 2340760] [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: 12/31/2022]
Abstract
We designed "passive measures" to control air pollution from burning coal in living rooms and have found the results satisfactory in reducing air pollution. The measures were simple, feasible and effective. They can be widely applied in the cold regions where living rooms are heated by burning coal.
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293
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Brade L, Holst O, Kosma P, Zhang YX, Paulsen H, Krausse R, Brade H. Characterization of murine monoclonal and murine, rabbit, and human polyclonal antibodies against chlamydial lipopolysaccharide. Infect Immun 1990; 58:205-13. [PMID: 2294050 PMCID: PMC258430 DOI: 10.1128/iai.58.1.205-213.1990] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [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: 12/31/2022] Open
Abstract
Murine monoclonal and rabbit, murine, and human polyclonal antibodies against chlamydial lipopolysaccharide (LPS) were characterized by the passive hemolysis and passive hemolysis inhibition assays and by absorption experiments with LPSs of Chlamydia psittaci, Chlamydia trachomatis, and a recombinant strain of Salmonella minnesota Re (r595-207) expressing the chlamydia-specific LPS epitope, as well as natural and synthetic partial structures of chlamydial LPS. Eleven monoclonal antibodies of the immunoglobulin M and G classes were characterized as chlamydia-specific by their failure to react with Re-type LPS, binding to a similar epitope for which the trisaccharide alpha-3-deoxy-D-manno-2-octulosonic acid (KDO)-(2-8)-alpha-KDO-(2-4)-alpha-KDO was an absolute prerequisite. For optimal binding, parts of the lipid A moiety were also involved; however, phosphoryl and ester-linked acyl groups and the reducing glucosamine residue of lipid A were dispensable. A similar antibody specificity was detected in lapine and murine hyperimmune sera after immunization with chlamydia, in addition to those recognizing more complex (e.g., those requiring the presence of phosphoryl residues) and less complex epitopes. Among the latter were those cross-reacting with Re-type LPS, which could be removed by absorption. The titers of different antibody specificities, in particular the ratio of chlamydia-specific to cross-reactive antibodies, present in murine polyclonal antisera depended on the immunization protocol. The preferential formation of chlamydia-specific antibodies was observed after immunization with liposome-incorporated immunogens. Human sera from patients with suspected genital chlamydial infections were also found to contain chlamydia-specific and cross-reactive antibodies, the latter of which could be removed by absorption with Re-type LPS.
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Affiliation(s)
- L Brade
- Division of Biochemical Microbiology, Forschungsinstitut Borstel, Federal Republic of Germany
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294
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Chen Y, Zhang YX. Use of monoclonal antibodies to glial fibrillary acidic protein in the cytologic diagnosis of brain tumors. Acta Cytol 1989; 33:922-8. [PMID: 2588925] [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: 01/01/2023]
Abstract
Monoclonal antibodies were used to immunocytochemically demonstrate glial fibrillary acidic protein (GFAP) in 174 smear preparations of brain tumor tissue in order to investigate the presence and distribution of GFAP in a variety of intracranial tumors and to evaluate the value of this technique in the cytodiagnosis of brain tumors. GFAP-positive cells were found in the astrocytic tumors and in some of the oligodendrogliomas, ependymomas and medulloblastomas. In contrast, schwannomas, meningiomas, a primary lymphoma, a hemangiopericytoma pituitary adenomas, germinomas and metastatic tumors were negative for GFAP. The cytodiagnostic accuracy of the 174 brain tumors was raised from 90.8% to 97.1% when GFAP-immunoperoxidase staining was employed to aid the routine cytologic diagnosis. These findings indicate that immunoperoxidase staining for GFAP can be successfully applied to cytologic specimens and is a useful adjunct to routine cytologic diagnosis.
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Affiliation(s)
- Y Chen
- Department of Pathology, First Medical College of PLA, Guangzhou, People's Republic of China
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295
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Zhang YX, Morrison SG, Caldwell HD, Baehr W. Cloning and sequence analysis of the major outer membrane protein genes of two Chlamydia psittaci strains. Infect Immun 1989; 57:1621-5. [PMID: 2707861 PMCID: PMC313324 DOI: 10.1128/iai.57.5.1621-1625.1989] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.9] [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: 01/02/2023] Open
Abstract
We cloned and sequenced the gene encoding the major outer membrane protein (MOMP) of two Chlamydia psittaci strains, guinea pig inclusion conjunctivitis (GPIC) strain 1, and meningopneumonitis (Mn) strain Cal-10. Intraspecies alignment of the two C. psittaci MOMP genes revealed 80.6% similarity, and interspecies comparison of C. trachomatis and C. psittaci MOMP genes yielded about 68% similarity. As found previously for C. trachomatis MOMP sequences, stretches of predominantly conserved sequences of GPIC and Mn MOMPs were interrupted by four variable domains whose locations were identical to those of C. trachomatis MOMPs. Seven of eight cysteine residues were found at precisely the same positions in GPIC, Mn, and C. trachomatis MOMPs, emphasizing their importance in structure and function of the protein. Collectively, these results indicate that C. psittaci and C. trachomatis MOMP genes diverged from a common ancestor.
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Affiliation(s)
- Y X Zhang
- Laboratory of Microbial Structure and Function, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840
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296
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Yuan Y, Zhang YX, Watkins NG, Caldwell HD. Nucleotide and deduced amino acid sequences for the four variable domains of the major outer membrane proteins of the 15 Chlamydia trachomatis serovars. Infect Immun 1989; 57:1040-9. [PMID: 2466791 PMCID: PMC313226 DOI: 10.1128/iai.57.4.1040-1049.1989] [Citation(s) in RCA: 194] [Impact Index Per Article: 5.5] [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: 01/01/2023] Open
Abstract
The amino acid sequences of major outer membrane proteins (MOMPs) from Chlamydia trachomatis serovars A, B, C, L1, and L2 are predominantly conserved but have four variable domains (VDs) in which major neutralizing and serotyping antigenic determinants are located. Because these MOMP VDs are primarily responsible for antigenic differences between serovars and are associated with important immunological and biological properties, we undertook studies focused on defining these sequences within the MOMPs of all 15 C. trachomatis serovars. We used oligonucleotide primer extension sequencing of MOMP mRNA to determine the nucleotide and deduced amino acid sequences of the four MOMP VDs of the 15 C. trachomatis serovars. Comparative amino acid sequence homologies of all four domains separated the serovars into three groups: group 1, serovars B, Ba, D, E, L1, and L2; group 2, serovars G and F; and group 3, serovars A, C, H, I, J, K, and L3. Hydrophilicity and charge values for each domain were determined. The MOMP VDs of given serovars with the greatest total hydrophilicity and charge values were found to be the location of antigenic determinants recognized by MOMP-specific monoclonal antibodies. These findings should be useful for predicting MOMP antigenic determinants and testing the antigenic properties of these VDs by using synthetic peptides corresponding to each MOMP VD. The potential usefulness of the VD sequence information is discussed in relation to the development of defined synthetic peptides and oligonucleotides that may be used to develop new serological and diagnostic assays for C. trachomatis infections.
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Affiliation(s)
- Y Yuan
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840
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297
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Abstract
Human liver guanosine triphosphate (GTP) cyclohydrolase I has been purified more than 1,700-fold to what appears to be homogeneity. The active enzyme complex has an estimated molecular weight of 453,000 +/- 11,500 by gel filtration chromatography. It consists of a polypeptide of 149,000 +/- 4,000 mol wt by SDS-polyacrylamide gel electrophoresis. The activity of the enzyme is heat stable and is inhibited by di- and trivalent cations. The enzyme has an optimum pH of 7.7 in sodium phosphate buffer. It uses GTP as a sole substrate, with a Km of 116 microM.
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Affiliation(s)
- R S Shen
- Department of Human Biological Chemistry & Genetics, University of Texas Medical Branch, Galveston 77550
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298
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Meng XJ, Sun Y, Chen MH, Liu ZH, Zhang YX, Li XZ, Li K, Han RC, Si JY, Hu LY. Viral etiology of cervical carcinoma. Human papilloma virus and herpes simplex virus type 2. Chin Med J (Engl) 1989; 102:94-9. [PMID: 2550184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The possible role of human papilloma virus (HPV) and herpes simplex virus type 2 (HSV-2) in the viral etiology of cervical carcinoma was investigated a series of cervical lesions were studied for the presence of HPV and HSV-2 DNA sequences as well as HPV and HSV-2 antigens by DNA dot blot hybridization technique and high-specificity PAP staining method. The results obtained were correlated with the histologic diagnosis. HPV 16 DNA sequences detected in cervical carcinoma biopsies were 43%, whereas HSV-2 DNA sequences were only 8%. HPV antigens detected in cervical dysplasia were 31%, whereas those detected in cervical carcinoma and cervicitis were the least. HSV-2 antigens were detected in chronic cervicitis, dysplasia and cervical carcinoma. The difference in positive rate between the cervical carcinoma and cervicitis groups was statistically significant, (chi-square test, P less than 0.01). No HPV DNA and HSV-2 DNA sequences were found in the same specimen, although both HPV DNA sequences and HSV-2 antigens were found in the same sample in some cases. The results indicate that the viral etiology of cervical carcinoma may be multifactorial. Both HSV-2 and HPV may be associated with cervical carcinoma, but the mechanisms involved are different. HSV-2 and HPV may act synergistically in the development of cervical carcinoma.
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299
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Zhang YX, Stewart SJ, Caldwell HD. Protective monoclonal antibodies to Chlamydia trachomatis serovar- and serogroup-specific major outer membrane protein determinants. Infect Immun 1989; 57:636-8. [PMID: 2463971 PMCID: PMC313145 DOI: 10.1128/iai.57.2.636-638.1989] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.4] [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: 01/01/2023] Open
Abstract
Monoclonal antibodies exhibiting Chlamydia trachomatis serovar specificity (serovar A, B-Ba, or C) and serogroup specificity (B, intermediate, or C serogroup) were produced and characterized. These antibodies reacted with the major outer membrane protein, recognized epitopes located at the chlamydial cell surface, and passively neutralized chlamydial toxicity for mice. The antibodies should be useful reagents for defining the molecular structure of these protective epitopes, a necessary step toward the development of a subunit or recombinant C. trachomatis vaccine.
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Affiliation(s)
- Y X Zhang
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840
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300
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Zhang YX. [Studies on the rat model of surgically evoked acute liver failure]. Zhonghua Yi Xue Za Zhi 1989; 69:95-9. [PMID: 2670105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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