401
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He B. Principles and applications of the Laplacian electrocardiogram. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 1997; 16:133-8. [PMID: 9313091 DOI: 10.1109/51.620505] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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402
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Ligers A, He B, Fogdell-Hahn A, Olerup O, Hillert J. No linkage or association of a VNTR marker in the junction region of the immunoglobulin heavy chain genes in multiple sclerosis. EUROPEAN JOURNAL OF IMMUNOGENETICS : OFFICIAL JOURNAL OF THE BRITISH SOCIETY FOR HISTOCOMPATIBILITY AND IMMUNOGENETICS 1997; 24:259-64. [PMID: 9306094 DOI: 10.1111/j.1365-2370.1997.tb00019.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Multiple sclerosis (MS) is a demyelinating inflammatory disease of the central nervous system. Autoantibodies are though to participate in the pathogenesis. Previous reports on the role of immunoglobulin (Ig) variable gene segments in MS are contradictory. Here, by using a highly polymorphic variable number tandem repeat (VNTR) marker located in the centre of the IgH chain locus, we demonstrate a lack of linkage and association with MS in 34 multiplex families and 113 sporadic MS patients in Sweden. Stratification for the presence or absence of the MS-associated HLA-Dw2 haplotype did not influence the negative outcome. We conclude that the IgH chain genes are unlikely to play a role in genetic susceptibility to MS in the Swedish population.
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403
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He B, Chou J, Brandimarti R, Mohr I, Gluzman Y, Roizman B. Suppression of the phenotype of gamma(1)34.5- herpes simplex virus 1: failure of activated RNA-dependent protein kinase to shut off protein synthesis is associated with a deletion in the domain of the alpha47 gene. J Virol 1997; 71:6049-54. [PMID: 9223497 PMCID: PMC191863 DOI: 10.1128/jvi.71.8.6049-6054.1997] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Earlier studies have shown that infection of human cells by herpes simplex virus 1 (HSV-1) results in the activation of RNA-dependent protein kinase (PKR) but that the alpha subunit of eIF-2 is not phosphorylated and that protein synthesis is unaffected. In the absence of the viral gamma(1)34.5 gene, eIF-2alpha is phosphorylated and protein synthesis is prematurely shut off (J. Chou, J. J. Chen, M. Gross, and B. Roizman, Proc. Natl. Acad. Sci. USA 92:10516-10520, 1995). A second recent paper reported the selection of second-site suppressor mutants characterized by near-wild-type protein synthesis in cells infected with gamma(1)34.5- mutants (I. Mohr and Y. Gluzman, EMBO J. 15:4759-4766, 1996). Here, we report the properties of the spontaneous HSV-1 suppressor mutant Sup-1, which is characterized by spontaneous deletion of 503 bp encompassing the domain of the alpha47 gene and junction with the inverted repeats flanking the unique short (U(S)) sequence of the HSV-1 DNA resulting in the juxtaposition of the alpha47 promoter to the coding domain of the U(S)11 gene. This mutant does not exhibit the shutoff of protein synthesis characteristic of the gamma(1)34.5- virus. Specifically, Sup-1 in SK-N-SH human neuroblastoma cells (i) did not exhibit the function of the alpha47 gene characterized by a reduction in the transport of peptides across the endoplasmic reticulum of permealized cells consistent with the absence of alpha47 gene sequences, (ii) accumulated U(S)11 protein at levels analogous to those of the wild-type parent but the protein was made at earlier times after infection, as would be expected from a change in the promoter, and (iii) activated PKR like that of the parent, gamma(1)34.5- virus, but (iv) did not cause premature shutoff of protein synthesis and therefore was similar to the wild-type parent virus rather than the gamma(1)34.5- virus from which it was derived. We conclude that the mechanism by which Sup-1 blocks the shutoff of protein synthesis associated with phosphorylation of eIF-2alpha by the activated PKR is not readily explainable by a secondary mutation characterized by a deletion.
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404
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He B, Bai JH, Zhou HM. Comparison of inactivation and unfolding of yeast alcohol dehydrogenase during thermal denaturation. Int J Biochem Cell Biol 1997; 29:1021-8. [PMID: 9375382 DOI: 10.1016/s1357-2725(97)00021-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It has been reported that inactivation occurs before noticeable conformational change can be detected during denaturation of creatine kinase (ATP:creatine N-phosphotransferase, EC 2.7.3.2) and other enzymes by guanidinium chloride or urea. It has therefore been suggested that enzyme active sites may display more conformational flexibility than the enzyme molecules as a whole. The present paper compares the inactivation and unfolding of yeast alcohol dehydrogenase during thermal denaturation. Under identical conditions, inactivation takes place before noticeable conformational changes. Kinetics of unfolding can be resolved into two phases. For a given temperature, the fast phase rates are about one order of magnitude slower than the inactivation rates of the free enzyme and approximately the same magnitude as the inactivation rates of enzyme-substrate complexes. This is general accord with the suggestion made previously by Tsou, indicating that the active sites of metal enzymes are situated in a region more flexible than the molecules as a whole.
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405
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Abstract
A new approach is proposed to solve bioelectric inverse problems by employing the surface Laplacian of the bioelectrical potential. A theoretical investigation was conducted to test the feasibility of epicardial inverse imaging of cardiac electrical activity. A two-sphere homogeneous volume conductor model, where the inner sphere represents the epicardium and the outer sphere the body surface, was used. Radial and tangential current dipoles were used to approximate localized wavefronts propagating from the endocardium to the epicardium, and ectopic myocardial activities. The epicardial potential distribution was reconstructed from the body surface Laplacians with the aid of the Tikhonov zero-order regularization technique, which then was compared with the results obtained from the body surface potentials using the same regularization scheme. The two inverse solutions were compared qualitatively via visual inspection of the reconstructed epicardial potential maps, and quantitatively by examining relative errors and correlation coefficients between the "true" and the reconstructed epicardial potentials. Both qualitative and quantitative results indicate that the surface Laplacians play a positive role in improving the ill-posed nature of the bioelectric inverse problem, which would enhance our capability of reconstructing important epicardial events such as extrema in the epicardial potential distribution. The present theoretical study suggests that the Laplacian-based inverse imaging technique may have important applications to epicardial inverse imaging and other bioelectric inverse imaging.
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406
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He B, Chen X, Li J, Jiang T, Luo J. [Effects of extract of Cortex Ilicis Rotundae on cardiovascular pharmacology]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 1997; 20:303-6. [PMID: 12572477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
In thes paper, the effects of Cortex Ilicis Rotundae (CIR) on Cardiovascular Pharmacology are studied. The results show that ethyl alcohol extract of CIR can reduce coronary blood flow, weaken myocardial contractility, slow down heart rates, prolong survival time of mice and prevent arrhythmias, the roles of CIR decoction are similar to ethyl alcohol extract, but it is not markable on heart rates and myocardial contractility.
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407
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Lyakhov DL, He B, Zhang X, Studier FW, Dunn JJ, McAllister WT. Mutant bacteriophage T7 RNA polymerases with altered termination properties. J Mol Biol 1997; 269:28-40. [PMID: 9192998 DOI: 10.1006/jmbi.1997.1015] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have identified mutants of bacteriophage T7 RNA polymerase (RNAP) that are altered in their ability to pause or terminate at a variety of signals. These signals include a terminator found fortuitously in the human preproparathyroid hormone (PTH) gene, a pause site found in the concatamer junction (CJ) of replicating T7 DNA, and termination signals that are also utilized by Escherichia coli RNAP (e.g. rrnB T1 and T2). Whereas the mutant enzymes terminate normally at the late terminator in T7 DNA (T(phi)) and rrnB T2, they fail to terminate at one of the termination sites of rrnB T1, and also fail to recognize the PTH and CJ signals. The mutant enzymes exhibit normal processivity on linear templates, but show a slightly reduced processivity on supercoiled templates and terminate more efficiently when synthesizing poly(U) tracts. The mutant enzymes also show a decreased tendency to produce aberrant transcription products from DNA templates having protruding 3' ends. T7 lysozyme (an inhibitor of T7 RNAP) has been shown to exert its action by preventing the transition of the RNAP from an unstable initiation complex (IC) to a stable elongation complex (EC). We have found that T7 lysozyme enhances recognition of CJ by wild-type T7 RNAP, and that mutant T7 RNAPs that show increased sensitivity to lysozyme show enhanced recognition of this signal, even in the absence of lysozyme. These results, together with the observation that the mutations that result in the termination-deficient phenotype affect a region of the RNAP that has been implicated in RNA binding and upstream promoter contacts, support the hypothesis that, in some cases, termination represents a reversal of the events that occur during initiation.
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408
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Edwards GL, White BD, He B, Dean RG, Martin RJ. Elevated hypothalamic neuropeptide Y levels in rats with dorsomedial hindbrain lesions. Brain Res 1997; 755:84-90. [PMID: 9163543 DOI: 10.1016/s0006-8993(97)00107-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lesions centered on the area postrema (AP) and adjacent nucleus of the solitary tract (AP/mNTS-lesions) are reported to result in increased consumption of highly palatable diets. Recent studies suggest that neuropeptide Y (NPY) may cause a preference for carbohydrate-rich diets. Thus, it is possible that NPY may play a role in the enhanced intake of highly palatable diets by AP/mNTS-lesioned rats. In the studies reported here, we found that lesions centered on the AP result in increased levels of NPY-immunoreactivity in the paraventricular nucleus of the hypothalamus. Additionally, steady-state NPY mRNA in the basomedial hypothalamus including the arcuate nucleus was elevated. Enhanced NPY was not found throughout the hypothalamus however, as NPY-immunoreactivity was not elevated in the lateral hypothalamus or the tissue bordering the anteroventral third ventricle. These data suggest the possibility that elevated hypothalamic NPY, particularly in the arcuate and paraventricular nuclei, may contribute to the altered food intake and energy balance observed in rats with lesions centered on the AP.
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409
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Yellman C, Tao H, He B, Hirsh J. Conserved and sexually dimorphic behavioral responses to biogenic amines in decapitated Drosophila. Proc Natl Acad Sci U S A 1997; 94:4131-6. [PMID: 9108117 PMCID: PMC20580 DOI: 10.1073/pnas.94.8.4131] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A preparation of decapitated Drosophila melanogaster has been used for direct application of drugs to the nerve cord. Serotonin, dopamine, and octopamine stimulate locomotion and grooming, showing distinguishable effects that often are potentiated by addition of the vertebrate monoamine oxidase-inhibitor hydrazaline. Many of the hydrazaline-induced effects are sexually dimorphic, with males showing greater responses than females. Behaviors similar to those induced by dopamine can be induced by application of the vertebrate dopamine D2-like receptor agonist quinpirole, whose effects are also sexually dimorphic. In contrast, vertebrate D2-like and D1-like dopamine antagonists result in akinesic states, and D1-like agonists selectively stimulate grooming. These data indicate that Drosophila nerve cord amine receptors are coupled to reflexive behaviors similar to those stimulated by brain dopamine receptors in vertebrates.
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410
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He B, Bansal S, Tsai A, Saul JP. A comparison of volume conductor effects on body surface Laplacian and potential ECGS: a model study. Comput Biol Med 1997; 27:117-27. [PMID: 9158918 DOI: 10.1016/s0010-4825(96)00037-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The objective of this investigation is to study, using a computer model, the torso volume conductor effects on body surface potential electrograms and body surface Laplacian electrograms. A spherical volume conductor model was used to approximate the torso and the heart. Myocardial electrical events were approximated by two distributed dipole-layers representing activation wavefronts propagating from the endocardium to the epicardium. The present computer simulation results indicate that the body surface Laplacian maps provide enhanced performance over the body surface potential maps in resolving the configurations of two activation wavefronts over the anterior wall of the heart.
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411
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He B, Gross M, Roizman B. The gamma(1)34.5 protein of herpes simplex virus 1 complexes with protein phosphatase 1alpha to dephosphorylate the alpha subunit of the eukaryotic translation initiation factor 2 and preclude the shutoff of protein synthesis by double-stranded RNA-activated protein kinase. Proc Natl Acad Sci U S A 1997; 94:843-8. [PMID: 9023344 PMCID: PMC19601 DOI: 10.1073/pnas.94.3.843] [Citation(s) in RCA: 604] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In human cells infected with herpes simplex virus 1 the double-stranded RNA-dependent protein kinase (PKR) is activated but phosphorylation of the alpha subunit of eukaryotic translation initiation factor 2 (eIF-2) and total shutoff of protein synthesis is observed only in cells infected with gamma(1)z34.5- mutants. The carboxyl-terminal 64 aa of gamma(1)34.5 protein are homologous to the corresponding domain of MyD116, the murine growth arrest and DNA damage gene 34 (GADD34) protein and the two domains are functionally interchangeable in infected cells. This report shows that (i) the carboxyl terminus of MyD116 interacts with protein phosphatase 1alpha in yeast, and both MyD116 and gamma(1)34.5 interact with protein phosphatase 1alpha in vitro; (ii) protein synthesis in infected cells is strongly inhibited by okadaic acid, a phosphatase 1 inhibitor; and (iii) the alpha subunit in purified eIF-2 phosphorylated in vitro is specifically dephosphorylated by S10 fractions of wild-type infected cells at a rate 3000 times that of mock-infected cells, whereas the eIF-2alpha-P phosphatase activity of gamma(1)34.5- virus infected cells is lower than that of mock-infected cells. The eIF-2alpha-P phosphatase activities are sensitive to inhibitor 2. In contrast to eIF-2alpha-P phosphatase activity, extracts of mock-infected cells exhibit a 2-fold higher phosphatase activity on [32P]phosphorylase than extracts of infected cells. These results indicate that in infected cells, gamma(1)34.5 interacts with and redirects phosphatase to dephosphorylate eIF-2alpha to enable continued protein synthesis despite the presence of activated PKR. The GADD34 protein may have a similar function in eukaryotic cells. The proposed mechanism for maintenance of protein synthesis in the face of double-stranded RNA accumulation is different from that described for viruses examined to date.
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412
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He B, Rong M, Lyakhov D, Gartenstein H, Diaz G, Castagna R, McAllister WT, Durbin RK. Rapid mutagenesis and purification of phage RNA polymerases. Protein Expr Purif 1997; 9:142-51. [PMID: 9116496 DOI: 10.1006/prep.1996.0663] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have developed plasmid-based expression systems that encode modified forms of T7 RNA polymerase (RNAP) having 6-12 histidine residues fused to the amino terminus. The histidine-tagged RNAPs (His-T7 RNAPS) are indistinguishable from the wild-type (WT) enzyme in nearly all biochemical assays. Similar plasmids that encode His-tagged T3 and SP6 RNAPs have also been constructed. To facilitate site-directed mutagenesis of the RNAP gene, the size of the target plasmid was minimized by using T7 RNAP itself as a selectable marker. BL21 (DCAT4) cells (which carry a chromosomal copy of the chloramphenicol acetyltransferase cat gene under control of a T7 promoter) are resistant to chloramphenicol when functional T7 RNAP is expressed, thus allowing the selection and maintenance of the target plasmid in these cells. Mutagenesis is accomplished by denaturing the plasmid, annealing mutagenic DNA primers, and repairing the plasmid with T4 DNA polymerase. Two DNA primers are used: one corrects a defect in the bla gene, the other introduces the desired mutation into the RNAP gene; 30-85% of the ampicillin-resistant transformants carry the desired mutation in the RNAP gene. By using BL21 (DCAT4) cells as a recipient for transformation the functional integrity of the RNAP gene may conveniently be monitored by assessing the level of chloramphenicol resistance in vivo. Methods for rapid, simultaneous purification of multiple samples of modified (His-tagged) and conventional RNAPs are described. Together, these developments greatly enhance our ability to characterize this important class of enzymes.
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413
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He B, Zhang T, Zhou HM. Comparison of inactivation and conformational changes of aminoacylase during denaturation in lithium dodecylsulphate solutions. Int J Biol Macromol 1997; 20:53-62. [PMID: 9110185 DOI: 10.1016/s0141-8130(97)01152-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The denaturation of aminoacylase in LDS solutions of different concentrations has been studied by following the changes in the ultraviolet absorbance, circular dichroism and intrinsic fluorescence. The results obtained show that the denaturation of the enzyme results in negative peaks at 287 and 295 nm in the denatured minus native enzyme difference spectrum. The fluorescence emission intensify of the enzyme decreases with no red shift of emission maximum in LDS solutions of increasing concentrations. In the LDS concentration regions employed in present study, no marked changes of secondary structure of the enzyme have been observed by following the changes in far ultraviolet CD spectra. The inactivation of this enzyme has been followed and compared with the unfolding observed during denaturation in LDS solutions. A marked inactivation is already evident at low LDS concentrations before signification conformational changes can be detected by ultraviolet absorbance and fluorescence changes. The inactivation rate constants of free enzyme and substrate-enzyme complex were determined by the kinetics method of the substrate reaction in the presence of inactivator previously described by Tsou. At the same LDS concentrations, the inactivation rate constants of the enzyme are a order of magnitude faster than the rate constants of conformational changes at least. The above results show that the active sites of metal enzyme containing Zn2+ are also situated in a limited and flexible region of the enzyme molecule that is more fragile to denaturants than the protein as a whole.
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414
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He B, Rong M, Durbin RK, McAllister WT. A mutant T7 RNA polymerase that is defective in RNA binding and blocked in the early stages of transcription. J Mol Biol 1997; 265:275-88. [PMID: 9018042 DOI: 10.1006/jmbi.1996.0741] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have identified a mutation (E148A) in T7 RNA polymerase (RNAP) that results in an enzyme which aborts transcription primarily when the nascent RNA achieves a length of 5 nt. This phenomenon is observed at a consensus promoter, but is even more strongly observed at promoters that are altered in the initiation region. Although the abortive product is of a fixed length (5 nt), the positions of the base substitutions in the initiation region that enhance this effect do not appear to be fixed, and we have observed the effect with a variety of initiation-region promoter variants. The phenomenon is also observed during promoter-independent transcription when transcribing a homopolymeric template such as poly(dC). Under conditions where the active site of the RNAP cannot extend beyond the third nucleotide in the template strand and the maximum length of the RNA:DNA hybrid cannot exceed three base-pairs (i.e. when synthesizing oligoG products due to transcript slippage at a promoter that initiates with the sequence +1 GGG...) the mutant RNAP gives rise to a normal spectrum of products 2 to 14 nt in length with no evidence of a block at 5 nt. Neither promoter binding nor promoter melting appears to be involved in this phenotype, as the mutant RNAP binds normally to promoter sequences and the behavior of the enzyme is unaffected by removal of the non-template strand in the initiation region of the promoter or on a supercoiled template. Importantly, the mutant RNAP is defective in binding single strand oligomers of RNA. These results suggest that the affected region of the RNAP may form part of the RNA product binding site and may be involved in the transition from an unstable initiation complex to a stable elongation complex, perhaps by sensing the presence of a nascent RNA and/or RNA:DNA hybrid.
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415
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Qi S, Yang Z, He B. [An experiment study of reversed pulmonary hypertension with inhaled nitric oxide on smoke inhalation injury]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1997; 35:56-8. [PMID: 10374512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
We evaluated the effect and mechanisms of reversed pulmonary hypertension with inhaled nitric oxide (NO) on smoke inhalation injury in the dog model, 21 dogs were divided into 3 groups randomly. Following smoke inhalation, the control group (n = 8) inhaled O2 (FiO2, 0.45) and the treated group (n = 9) inhaled O2 and 0.0045% (45 ppm) NO. Hemodynamics was serially measured for 12 hours. In addition, 4 dogs without smoke inhalation were used to study the normal lung histomophologic findings. The data were analyzed by ANOVA. After inhalation of NO, the mean pulmonary artery pressure (mPAP), pulmonary minute vessels pressure (Pmv), and pulmonary vascular resistance (PVR) were decreased significantly (P < 0.05), while the mean aortic pressure (mAP) and total peripheral resistance (TRP) were not remarkably changed (P > 0.05). The levels of cyclic guanosine monophosphate (cGMP) were increased significantly (P < 0.01). Inhaled NO may reverse pulmonary hypertension with smoke inhalation injury in dogs. The mechanism of selective pulmonary circulation was increased cGMP level in smooth cells. Inhaled NO may be recommended for clinical application.
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416
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He B, Wang S, Hao W. [Evaluation study on determination of ZPP in blood with hematofluorometer]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 1997; 26:9-12. [PMID: 15747452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The authors studied the normalization and evaluation of the method detecting the zinc protoporphyrin (ZPP) by direct displaying blood fluorescent. The results revealed that this method was highly accurate and precise. The relative humidity not more than 90% had no influence to the results. The detection limit of this method was 0.1 microg/g. The linear range of standard curve was 0-15 microg/g, and the precision in batch RSD=0.27%-1.93%. On the accuracy side, the three concentration curving values of ZPP standard material in blood were all within the range of indefinition of given values. If the samples were not detected rapidly and the blood was diluted by heparin, it might be preserved at 4 degrees C for 3 days, at -8 degrees C for 8 days. The blank fluorescent value of glassy cover made in China is less than 3.5 microg/g, Hb can substitute KLI glassy cover. This method can analyse one sample per minute, has advantage of rapidity, convenience, accuracy and reliablity.
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417
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Geist LJ, Hopkins HA, Dai LY, He B, Monick MM, Hunninghake GW. Cytomegalovirus modulates transcription factors necessary for the activation of the tumor necrosis factor-alpha promoter. Am J Respir Cell Mol Biol 1997; 16:31-7. [PMID: 8998076 DOI: 10.1165/ajrcmb.16.1.8998076] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Several studies have demonstrated that cytomegalovirus (CMV) infection increases expression of the tumor necrosis factor (TNF) gene. This effect is mediated, in part, by an effect of the CMV immediate early 1 (IE1) gene product on the TNF promoter. To further analyze these interactions, we used plasmids with TNF promoter truncations to determine the site within the promoter where the CMV IE1 gene product mediates its effect. The site was localized to a 40-base pair segment that contains a cAMP response element (CREB). Deletion of the cAMP response element increased basal promoter activation but had little effect on IE1-induced activation. Additional studies demonstrated that the cAMP element is flanked 5' by a PU.1 site and 3' by an NF-kappa B site, both of which increase expression of the TNF promoter. These sequences demonstrated IE1 responsiveness. We next determined the relevance of these observations for normal human cells by infecting human alveolar macrophages with CMV. In these studies we evaluated expression of NF-kappa B, PU.1 and CREB by gel shift assay at immediate early times after infection. We found that CMV infection increased the binding activity of NF-kappa B and PU.1 and decreased the binding activity of CREB. CMV infection also increased expression of the TNF gene in alveolar macrophages. These observations suggest that CMV increases TNF gene expression, in part, by altering the binding activity of transcription factors that regulate gene expression.
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418
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He B, Tang ZY, Liu KD, Zhou G. Analysis of the cellular origin of hepatocellular carcinoma by p53 genotype. J Cancer Res Clin Oncol 1996; 122:763-6. [PMID: 8954175 DOI: 10.1007/bf01209125] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The polymerase chain reaction and HaeIII enzymatic digestion were used to study the seventh exon of the p53 gene in 29 primary and recurrent hepatomas in paraffin-embedded samples from 11 patients. The mutation rate of the p53 gene and its genotypes in samples of primary and recurrent tumours and multiple nodules were investigated. The cellular origins of hepatocellular carcinoma were analysed by p53 genotype. p53 mutation rates were found to be 69.0% (20/29) in the primary and recurrent tumours, 58.8% (10/17) in tumours with a single nodule and 83.3% (10/12) in tumours with multiple nodules. The p53 genotypes were found to be different in 6 pairs of primary and recurrent tumours, and another 5 pairs had the same p53 genotypes. The samples with multiple nodules in the same patients had the same p53 genotypes. Seven recurrences were of multicentric origin and four were of unicentric origin. It is suggested that the recurrent lesions developed from both unicentric and multicentric origins.
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419
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Qian G, Zhou J, Ma J, Wang D, He B. The chemical modification of E. coli L-asparaginase by N,O-carboxymethyl chitosan. ARTIFICIAL CELLS, BLOOD SUBSTITUTES, AND IMMOBILIZATION BIOTECHNOLOGY 1996; 24:567-77. [PMID: 8922226 DOI: 10.3109/10731199609118882] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
E. coli L-asparaginase was modified with N,O-carboxymethyl chitosan in the presence of normal product L-aspartic acid, which protected the active site of the enzyme. The modified enzyme remained high catalytic activity, showed greater stability against trypsin and alpha-chymotrypsin, but lost its activity more rapidly at high temperature (> 45 degrees C) than did the native enzyme. When tested in vivo, the plasma half-life of the modified enzyme (t1/2 = 40 hr) was over 33 times longer than that of the native enzyme (t1/2 = 1.6 hr). The results showed that the modified L-asparaginase may be much more useful than did the native enzyme for clinical treatments of tumors.
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420
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Andreansky SS, He B, Gillespie GY, Soroceanu L, Markert J, Chou J, Roizman B, Whitley RJ. The application of genetically engineered herpes simplex viruses to the treatment of experimental brain tumors. Proc Natl Acad Sci U S A 1996; 93:11313-8. [PMID: 8876132 PMCID: PMC38054 DOI: 10.1073/pnas.93.21.11313] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Due to lack of effective therapy, primary brain tumors are the focus of intense investigation of novel experimental approaches that use vectors and recombinant viruses. Therapeutic approaches have been both indirect, whereby vectors are used, or direct to allow for direct cell killing by the introduced virus. Genetically engineered herpes simplex viruses are currently being evaluated as an experimental approach to eradicate malignant human gliomas. Initial studies with gamma (1)34.5 mutants, R3616 (from which both copies of the gamma (1)34.5 gene have been deleted) and R4009 (a construct with two stop codons inserted into the gamma (1)34.5 gene), have been assessed. In a syngeneic scid mouse intracranial tumor model, recombinant herpes simplex virus can be experimentally used for the treatment of brain tumors. These viruses and additional engineered viruses were subsequently tested in human glioma cells both in vitro and in vivo. Using a xenogeneic scid mouse intracranial glioma model, R4009 therapy of established tumors significantly prolonged survival. Most importantly, long-term survival was achieved, with histologic evidence that R4009 eradicated intracranial tumors in this model. Furthermore, the opportunity to evaluate gamma (1)34.5 mutants that have enhanced oncolytic activity, e.g., R8309 where the carboxyl terminus of the gamma (1)34.5 gene has been replaced by the murine homologue, MyD116, are considered.
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421
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Henderson JE, He B, Goltzman D, Karaplis AC. Constitutive expression of parathyroid hormone-related peptide (PTHrP) stimulates growth and inhibits differentiation of CFK2 chondrocytes. J Cell Physiol 1996; 169:33-41. [PMID: 8841420 DOI: 10.1002/(sici)1097-4652(199610)169:1<33::aid-jcp4>3.0.co;2-f] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have examined the effects of constitutive expression of PTHrP on the growth and differentiation of populations of cells derived from a clonal chondrocytic cell line, CFK2. Cells were stably transfected with cDNA encoding either full-length, secretory PTHrP (CFK2P) or nonsecretory PTHrP (CFK2P-SS). In cultures of cells plated at low density, secretory PTHrP acted as a potent mitogen compared with nonsecretory PTHrP or exogenous PTHrP-(1-34), both of which stimulated only a minor increase in proliferation. In populations of control cells maintained postconfluent for several weeks, there was a dramatic increase in expression of mRNA for type II collagen, aggrecan, and link protein. Addition of exogenous PTHrP-(1-34) at a concentration of 10(-8) M to these cultures was ineffective in inhibiting this time-dependent increase in expression of matrix proteins. In contrast, populations of cells producing either secretory or nonsecretory forms of PTHrP, maintained over the same time period, demonstrated an almost complete inhibition of mRNA expression for matrix proteins. These observations demonstrate that PTHrP acts as a bifunctional modulator of chondrogenesis and that some of its biological activity is exerted via a mechanism distinct from the recognised signal transduction pathways linked to the PTH/PTHrP receptor.
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422
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He B, Tang Z, Liu K. [Analysis of cell origin of human hepatocellular carcinoma according to p53 gene mutation]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1996; 18:335-8. [PMID: 9387269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Paraffin-embedded hepatocellular carcinoma (HCC) samples were used to study point mutation of p53 gene at 249 codon in the exon 7 by polymerase chain reaction and gel electrophoresis under Hae III enzyme digestion. Fourteen primary tumor foci and 15 recurrent tumor foci from 11 patients were investigated. p53 gene point mutation was detected in 10 of 14 primary foci (71.4%), in 10 of 15 recurrent foci (66.7%) and in 10 of 12 multiple foci. The p53 genotype of the primary and recurrent tumor foci was the same in 5 patients but different in 6. The p53 genotype of the primary and recurrent tumor foci was identical in 5 patients with multiple tumor nodules. The results suggest that recurrent HCC was multi-centric in origin in 7 of the 11 patients but was mono-centric in the other 4 patients studied.
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423
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Gao G, Peng Z, He B. [The value of urine cystein proteinase and serum CA125 measurement in monitoring the treatment of malignant ovarian tumor]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1996; 27:291-4. [PMID: 9389065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Urine cystein proteinase (UCP) and serum CA125 were measured in 40 patients with malignant ovarian tumor (malignant group), 40 patients with benign ovarian tumor (benign group), and 40 normal control (normal group). 28 patients in the malignant group underwent UCP and CA125 measurement pre-operation, post-operation, and during three courses of chemotherapy. The enzyme activity of UCP in the malignant group was significantly higher than that in the benign and normal groups (P < 0.05 or 0.01). The values of UCP in patients with malignant tumor of stages II-IV were significantly higher compared with those of stages I-II (P < 0.01, 0.05). The activity of UCP was elevated pre-operation, post-operation, and was much higher on the seventh day postoperation. After the seventh day, UCP activity decreased gradually. Serum CA125 was also detected pre-operation, at 7.30 and 60 days post-operation. The levels of UCP and CA125 pre-operation and 30, 60 days post-operation in the patients whose residual carcinoma lesions were > 2 cm in diameter were apparantly higher than those with no residual lesions (P < 0.05). UCP and CA125 values were measured in six patients before relaparotomy. The sensitivity, specificity, accuaracy, positive predictive value and negative predictive value for UCP assay are 980%, 100%, 83%, 100% and 50% and those for CA125 assay are 40%, 100%, 80%, 100%, and 25%, respectively.
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424
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Qie M, Peng Z, Cao Z, Tang Q, He B. [The value of CA125 and LDH assays in assisting diagnosis of epithelial ovarian carcinoma]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1996; 27:310-3. [PMID: 9389070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
40 first-treated cases of epithelial ovarian cancer, 13 cases of cervical cancer, 13 cases of corpus cancer and 50 cases of benign tumor were included in this study from Jan. 1991 through May 1992 to evaluate the significance of the blood CA125, LDH, CR and SA levels in assisting diagnosis of epithelical ovarian cancer. The CA125 levels of the 40 canses of ovarian cancer were higher than those of cervical cancer and corpus cancer (P < 0.05); the SS, PLR and AC of CA125 in ovarian cancer were higher than those of LDH, SA and CR (P < 0.05); the SS of CA125 in ovarian cancer was higher than that of LDH isoenzyme (P < 0.05). The results show that CA125 may be the best tumor marker in assisting ovarian cancer; CA125 is more informative than LDH, CR and SA; when CA125 is used incombination with other tumor markers, SS, SP, NPV and PPV can be greatly raised.
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425
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Mastronarde JG, He B, Monick MM, Mukaida N, Matsushima K, Hunninghake GW. Induction of interleukin (IL)-8 gene expression by respiratory syncytial virus involves activation of nuclear factor (NF)-kappa B and NF-IL-6. J Infect Dis 1996; 174:262-7. [PMID: 8699053 DOI: 10.1093/infdis/174.2.262] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Respiratory syncytial virus (RSV) preferentially infects respiratory epithelium and is an important cause of lower respiratory tract infections in young children. RSV induces the production of interleukin (IL)-8 in airway epithelial cells; however, the mechanism of this induction is not known. To define the mechanism by which RSV induces IL-8 gene activation, A549 epithelial cells were transfected with plasmids containing serial deletions of the 5'-flanking region of the IL-8 gene and then exposed to RSV for 24 h. A positive cooperative effect of the binding sites for the transcription factors, nuclear factor (NF)-kappa B and NF-IL-6, was observed. Mutations in either region abates responsiveness of the promoter to RSV infection. RSV also increases activation of the NF-kappa B and NF-IL-6 transcription factors. These data suggest that RSV may increase IL-8 production in airway epithelium partly via activation of the transcription factors NF-kappa B and NF-IL-6.
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