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Abstract
BACKGROUND The French-American-British group's proposal for the classification of chronic lymphoid leukemias is unique at this time. Testing, expanding, and adding to the theory by immunophenotyping will help to additionally characterize this group of diseases. METHODS Peripheral blood samples from 242 patients with chronic lymphoid leukemias were analyzed for immunologic evaluation of the following subtypes: typical chronic lymphocytic leukemia (CLL), 189; CLL with pleomorphic lymphocytes (CLL-pleo), 19; CLL of mixed cell type (CLL/PL), 20; prolymphocytic leukemia (PLL), 22; hairy cell leukemia (HCL), 10; HCL-variant, 1; and splenic lymphoma with villous lymphocytes, 1. RESULTS The phenotype of CLL and CLL-pleo was weak surface immunoglobulin (SIg) with positive results of mouse rosettes (MR+), CD5+, and CD22-. Of PLL and HCL, it was strong SIg, MR-, CD5-, and CD22+. By analyzing the four markers and accepting the relevant results of two or more as sufficient for diagnosis, all cases (100%) of CLL, CLL-pleo, PLL, and HCL were diagnosed. CLL/PL showed the phenotype of CLL in 66.67% and of PLL in 33.33% of patients. The frequency of cases with weak fluorescence in decreasing order was CLL, CLL-pleo, CLL/PL, and PLL and HCL. The same sequence applied to the mean percentage of mouse rosette-forming cells and CD5 cells, but the sequence was reversed for CD22 cells. CONCLUSIONS SIg intensity, MR, CD5, and CD22 constitute the minimum number of immune markers for the differential diagnosis of the subtypes of chronic lymphoid leukemia. The frequency of the four markers among the subtypes suggested that CLL and CLL-pleo have identical phenotypes and that the five subtypes follow a continuous range of B-cell differentiation from early mature (CLL and CLL-pleo) to late mature pre-plasma cell stages (PLL followed by HCL), with CLL/PL of intermediate maturity.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Antigens, CD/analysis
- Antigens, Differentiation, B-Lymphocyte/analysis
- CD5 Antigens
- Cell Adhesion Molecules
- Female
- Flow Cytometry
- Fluorescent Antibody Technique
- Humans
- Immunophenotyping
- Lectins
- Leukemia, Lymphocytic, Chronic, B-Cell/classification
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Male
- Middle Aged
- Receptors, Antigen, B-Cell/analysis
- Rosette Formation
- Sialic Acid Binding Ig-like Lectin 2
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377
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Shen B, Allard P, Kuprin S, Ehrenberg A. Studies on ribonucleoside-diphosphate reductase from Escherichia coli. The product dCDP is a competitive inhibitor and functions as a spectroscopic probe for the substrate binding site; demonstration by enzyme kinetics and 1H NMR. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 208:631-4. [PMID: 1396670 DOI: 10.1111/j.1432-1033.1992.tb17228.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ribonucleoside-diphosphate reductase (EC 1.17.4.1) from Escherichia coli consists of two protein subunits, R1 of 171.5 kDa and R2 of 86.8 kDa, and catalyzes the reduction of all four common ribonucleoside diphosphates. In a search for ligands that bind weakly to the enzyme active site and may be in fast exchange suitable for NMR studies, we have found that the product dCDP is a competitive inhibitor. Kinetics with CDP as substrate shows Km = 4.8 x 10(-5) M and dCDP inhibits with Ki = 1.6 x 10(-4) M. With an assumed diffusion limited binding rate approximately less than 10(9) M-1s-1, the dissociation rate of dCDP would be approximately less than 10(5) s-1. In 1H-NMR experiments studying linewidths, i.e. spin-spin relaxation, dCDP is indeed demonstrated to be in fast exchange. Enzyme subunit R1 causes a line broadening of dCDP resonances. Unexpectedly less broadening was observed when subunit R2 combined with R1. No paramagnetic interaction from the tyrosyl radical of R2 could be detected. It is concluded that dCDP is a promising NMR probe for studies of active-site properties of the enzyme.
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Allard P, Kuprin S, Shen B, Ehrenberg A. Binding of the competitive inhibitor dCDP to ribonucleoside-diphosphate reductase from Escherichia coli studied by 1H NMR. Different properties of the large protein subunit and the holoenzyme. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 208:635-42. [PMID: 1396671 DOI: 10.1111/j.1432-1033.1992.tb17229.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ribonucleoside-diphosphate reductase (EC 1.17.4.1) from Escherichia coli consists of two nonidentical subunits, proteins R1 and R2. The binding of the product dCDP to protein R1 and to the holoenzyme R1R2 has been studied by means of 1H-NMR spectroscopy. In presence of the effector dTTP at 25 degrees C, dCDP was found to be in rapid exchange between the binding sites and the solvent which results in a broadening of the dCDP resonances. When both proteins R1 and R2 are present, so that the complex R1R2 is formed, a smaller broadening is observed than with protein R1 alone. No further linewidth decrease was observed when the [R2]/[R1] ratio exceeded 1. The binding constant of dCDP to R1 or R1R2 is the same, Kd = 0.9 mM. The smaller broadening of the dCDP resonances observed with the complex R1R2 as compared with R1 may be explained by the combination of two effects: (a) the overall tumbling time of the protein will increase when going from R1 to R1R2, which will cause the broadening to increase correspondingly, and (b) a twofold decrease of the number of binding sites in rapid exchange, which will decrease the broadening by a factor of 0.5. The effect of R2 without iron (apoR2) is reduced compared with native R2, probably because of some denatured proteins, while a C-terminal peptide from R2 did not cause any narrowing at all.
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379
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Xu K, Meng XY, Wu JW, Shen B, Shi YC, Wei Q. Diagnostic value of serum gamma-glutamyl transferase isoenzyme for hepatocellular carcinoma: a 10-year study. Am J Gastroenterol 1992; 87:991-5. [PMID: 1353662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Serum gamma-glutamyl transferase (GGT) was separated into nine to 11 isoenzyme bands (designated as GGT I-XI) by vertical slab electrophoresis on polyacrylamide gradient gel. The diagnostic value of GGT isoenzyme II (GGT II) for hepatocellular carcinoma (HCC) was studied, and the results were as follows: 1) GGT II was positive in 90% of 90 cases of HCC, and negative in most patients with acute and chronic viral hepatitis, extrahepatic tumors, in pregnant women, and in healthy controls; 2) the positive rate of GGT II assay was higher than that of alkaline phosphatase isoenzyme I (ALP I), alpha-fetoprotein (AFP), and alpha 1-antitrypsin (AAT) in 101 cases of HCC. In cases in which the AFP was greater than 50 ng/ml or less than 50 ng/ml, the positive rates of GGT II were 70.8% and 75-100%, respectively; 3) of 14 cases of small-size HCC, the positive rate of GGT II was 78.6%, which was higher than that of AFP (50%), AAT (28.6%), and ALP I (0%); 4) of 62 cases that were false-positive for GGT II assay, 24.2% developed into HCC during a follow-up of 2.1-20 months. In subjects with persistent and recurrent positivity of GGT II, 86.7% and 22.2%, respectively, developed HCC. No patient with temporal positivity of GGT II developed HCC. The results show that GGT II can be applied as an additional marker for HCC, and is valuable not only for the diagnosis of clinical HCC, but for the detection of small or subclinical HCC. Periodic follow-up with assay of GGT II in patients at high risk for HCC may predict the development of hepatoma.
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380
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Batata A, Shen B. Relationship between chronic lymphocytic leukemia and small lymphocytic lymphoma. A comparative study of membrane phenotypes in 270 cases. Cancer 1992; 70:625-32. [PMID: 1623477 DOI: 10.1002/1097-0142(19920801)70:3<625::aid-cncr2820700314>3.0.co;2-d] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are considered different tissue expressions of the same disease process, although they are clinically separable nosologic entities. A systematic comparison of the membrane phenotypes in the two entities needs to be investigated. METHODS Cell suspensions from peripheral blood of 184 patients with CLL, bone marrow from 23 patients with CLL, and lymph nodes from 86 patients with SLL were analyzed to compare the membrane phenotypes. RESULTS There were no significant differences between the three groups in the mean percentages of cells expressing surface immunoglobulin (SIg), CD5, CD19, CD20, and CD2 or in the frequency of cases with weak SIg. Although the mean percentage of mouse rosette-forming cells (MRFC) showed no statistical difference between bone marrow from CLL and lymph nodes from SLL, the mean percentage of MRFC in peripheral blood from CLL (48.02 +/- 18.23%) was twice as high as that in bone marrow from CLL (25.27 +/- 21.51%) and lymph nodes from SLL (20.87 +/- 16.72%) (P less than 0.001). Correlation analysis assessing the association of MRFC and residual T-cells showed a negative coefficient (r), and the r was statistically significant in bone marrow from CLL and lymph nodes from SLL but not in peripheral blood from CLL. The mean CD4/CD8 ratios in descending order were as follows: the ratio in lymph nodes from SLL (4.25) was greater than that in peripheral blood from CLL (1.70), which was greater than that in bone marrow from CLL (0.82); this followed the same pattern as the respective tissue controls. The mean ratios were not statistically different from those of their respective control groups. CONCLUSIONS The similarity of membrane phenotypes between CLL and SLL provided evidence that the two are different tissue expressions of the same disease. The alterations in CD4/CD8 ratios were related to the type of tissue analyzed and not to the disease process. The difference in MRFC presumably results from the microenvironment or residual T-cells.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Antigens, CD/analysis
- Bone Marrow Examination
- CD4-CD8 Ratio
- Female
- Flow Cytometry
- Fluorescent Antibody Technique
- Humans
- Immunophenotyping
- Leukemia, Lymphocytic, Chronic, B-Cell/blood
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Male
- Middle Aged
- Receptors, Antigen, B-Cell/analysis
- Rosette Formation
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381
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Shen B, Summers RG, Gramajo H, Bibb MJ, Hutchinson CR. Purification and characterization of the acyl carrier protein of the Streptomyces glaucescens tetracenomycin C polyketide synthase. J Bacteriol 1992; 174:3818-21. [PMID: 1592832 PMCID: PMC206074 DOI: 10.1128/jb.174.11.3818-3821.1992] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The acyl carrier protein (ACP) of the tetracenomycin C polyketide synthase, encoded by the tcmM gene, has been expressed in both Streptomyces glaucescens and Escherichia coli and purified to homogeneity. Expression of the tcmM gene in E. coli results mainly in the TcmM apo-ACP, whereas expression in S. glaucescens yields solely the holo-ACP. The purified holo-TcmM is active in a malonyl coenzyme A:ACP transacylase assay and is labeled by radioactive beta-alanine, confirming that it carries a 4'-phosphopantetheine prosthetic group.
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382
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Leung LS, Shen B, Kaibara T. Long-term potentiation induced by patterned stimulation of the commissural pathway to hippocampal CA1 region in freely moving rats. Neuroscience 1992; 48:63-74. [PMID: 1584426 DOI: 10.1016/0306-4522(92)90338-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In urethane-anesthetized rats, stimulation of the contralateral hippocampal CA1 region resulted in activation of the homotopic CA1 region. Current-source-density analysis revealed that both basal and apical dendrites were activated. However, alveolar and stratum oriens stimulation in CA1 gave about equal peak excitation of the basal and apical dendrites while CA1 stratum radiatum/moleculare and CA3c stimulation gave stronger apical than basal dendritic excitation. In chronically implanted and freely moving rats, tetanic patterned stimulation of the contralateral CA1, irrespective of depth, resulted in a robust long-term potentiation of the ipsilateral CA1 basal dendritic synapse. The population basal dendritic excitatory postsynaptic potential was initially potentiated to greater than 200% of the baseline and decayed with a 3 h time constant; it lasted at least two days. Patterned stimulation of the commissural inputs at 2 x threshold stimulus intensity seldom potentiated the apical dendritic synapse in CA1; rather, long-term depression was sometimes observed. After tetanic stimulations at 3 x threshold, a small potentiation of the apical dendritic excitation was seen in about half of the experiments. The average apical dendritic potentiation peaked at about 25% and persisted to at least one day. This study provides original evidence that the properties of long-term potentiation are different at the commissural basal dendritic and apical dendritic synapses in CA1 of the behaving rat. Basal dendritic potentiation is low-threshold, high-amplitude and decayed rapidly in the first 3 h. Apical dendritic potentiation is high-threshold, low-amplitude and not rapidly decaying. A long-lasting enhancement of synaptic transmission has been postulated as a physiological correlate of memory. This paper reports properties of this synaptic enhancement for two different types of synapses on the same cells in the behaving animal. The basal dendritic synapse on hippocampal pyramidal cells readily increased their efficacy, up to at least two days, after a brief, patterned stimulation. In the same preparation, it was difficult to obtain a long-lasting increase in the apical dendritic excitation, in contrast to studies on isolated hippocampal slices in vitro.
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383
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Batata A, Shen B. Mouse rosettes and surface immunoglobulin in small lymphocytic lymphoma. Importance in immunophenotyping and differential diagnosis. Cancer 1992; 69:1021-30. [PMID: 1735069 DOI: 10.1002/1097-0142(19920215)69:4<1021::aid-cncr2820690432>3.0.co;2-u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cell suspensions from lymphoid tissue of 82 small lymphocytic lymphoma (SLL), 8 intermediate lymphocytic lymphoma (ILL), 286 other B-non-Hodgkin's lymphoma (B-NHL), and 248 reactive lymphadenopathy (RLA) cases were analyzed to evaluate the diagnostic significance of mouse-rosette (M-rosette) assay, and surface immunoglobulin clonality (SIg) and level of expression. In SLL, 55 were M-rosette positive (67.07%) and 72 SIg positive (87.8%), with weak fluorescence in 63 and strong fluorescence in 9 cases. Of 10 SIg-negative cases, 9 were M-rosette positive; of 27 M-rosette-negative cases, 26 were SIg positive. Seven of the nine cases with strong fluorescence were M-rosette positive. In other B-NHL, 252 were M-rosette negative (88.11%) and 245 SIg positive (85.66%), with strong fluorescence in 211 and weak fluorescence in 34 cases. Thirty-two of the 34 cases with weak fluorescence were M-rosette negative. Of the RLA cases, 213 were M-rosette negative (85.89%) and 1 SIg positive (0.4%). The study demonstrated the independent expression of M-rosettes and SIg in SLL and their complementary role in diagnosis. It showed that positive results for M-rosettes and weak fluorescence are characteristic of SLL, that M-rosette negativity and strong fluorescence are characteristic of other B-NHL, and that M-rosette negativity and polyclonal SIg are characteristic of RLA. In 26 cases with paired data for CD5, M-rosettes, and SIg, a positive result for M-rosettes was superior to CD5 in differentiating SLL from other B-NHL. Intermediate lymphocytic lymphoma frequently showed weak SIg fluorescence and M-rosette negativity.
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384
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Handelman GJ, Shen B, Krinsky NI. High resolution analysis of carotenoids in human plasma by high-performance liquid chromatography. Methods Enzymol 1992; 213:336-46. [PMID: 1435309 DOI: 10.1016/0076-6879(92)13135-k] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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385
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Shen B, Gould SJ. Opposite facial specificity for two hydroquinone epoxidases: (3-si,4-re)-2,5-dihydroxyacetanilide epoxidase from Streptomyces LL-C10037 and (3-re,4-si)-2,5-dihydroxyacetanilide epoxidase from Streptomyces MPP 3051. Biochemistry 1991; 30:8936-44. [PMID: 1892811 DOI: 10.1021/bi00101a004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
(3-si,4-re)-2,5-Dihydroxyacetanilide epoxidase (DHAE I), a key enzyme in the biosynthesis of the epoxysemiquinone antibiotic LL-C10037 alpha by Streptomyces LL-C10037 [Gould, S.J., & Shen, B. (1991) J. Am. Chem. Soc. 113, 684-686], and (3-re,4-si)-2,5-dihydroxyacetanilide epoxidase (DHAE II) isolated from Streptomyces MPP 3051--which yields the (3R,4S)-epoxyquinone mirror image product of DHAE I--are described. DHAE I was purified 640-fold. Gel permeation chromatography indicated an Mr of 117,000 +/- 10,000; SDS-PAGE gave a major band of 22,300 daltons, indicating that DHAE I is either a pentamer or hexamer in solution. The enzyme had a pH optimum of 6.5, a Km of 8.4 +/- 0.5 microM, and a Vmax of 3.7 +/- 0.2 mumol min-1 mg-1. DHAE II was purified 1489-fold. The enzyme was shown to be a dimer of Mr 33,000 +/- 2000, with 16,000-dalton subunits, with a pH optimum of 5.5 and a Km of 7.2 +/- 0.4 microM. Both enzymes required only O2 and substrate; flavin and nicotinamide coenzymes had little or no effect. Neither catalase nor EDTA affected the activity of either enzyme, but complete inhibition of both was obtained with 1,10-phenanthroline. The activity of the purified DHAE I could be enhanced, but only by Mn2+ (relative V = 246 at 0.04 mM), Ni2+ (relative V = 266 at 0.2 mM), or Co2+ (relative = 498 at 0.2 mM). Reconstitution from a DHAE I apoenzyme, generated by treatment with 1,10-phenanthroline followed by Sephadex G-25 chromatography, occurred only by addition of one of these three metals.(ABSTRACT TRUNCATED AT 250 WORDS)
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386
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Leung LS, Shen B. Hippocampal CA1 evoked response and radial 8-arm maze performance after hippocampal kindling. Brain Res 1991; 555:353-7. [PMID: 1933343 DOI: 10.1016/0006-8993(91)90365-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Rats with chronically implanted electrodes in the hippocampal CA1 region were trained in the open radial 8-arm maze and then subjected to kindling (afterdischarges, ADs) or 0.17 Hz low-frequency stimulations (LFSs) as controls. Partial kindling (21 ADs) induced a general increase of AD threshold but no motor convulsions. The commissurally evoked average evoked potentials (AEPs) in CA1 were enhanced above the pre-AD baseline or the AEPs in LFS control rats at 1 day after the 1st, 6th, 11th and 16th AD and for at least 25 days after 21 ADs. Similarly, maze performance was significantly worse in kindled than LFS rats for about 4 weeks after 21 ADs/LFSs. The study confirms the long-lasting behavioral effect of partial kindling and suggests that synaptic enhancement may underlie the behavioral disruption.
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387
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Batata A, Shen B. The importance of surface immunoglobulin, mouse rosettes, and CD5 in the immunophenotyping of chronic lymphocytic leukemia and reactive lymphocytosis. Cancer 1991; 68:355-61. [PMID: 2070335 DOI: 10.1002/1097-0142(19910715)68:2<355::aid-cncr2820680225>3.0.co;2-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Peripheral blood from 167 B-chronic lymphocytic leukemia (B-CLL) and 119 reactive lymphocytosis (RLC) patients were analyzed to evaluate the immunophenotypic diagnostic value of mouse rosettes (M-rosette), and weak expression of monoclonal surface immunoglobulin (SIg). In B-CLL, 145 cases were M-rosette+ (86.83%), 135 surface immunoglobulin (SIg)+ (80.84%), and 117 M-rosette+ SIg+ (70.06%). Of 32 SIg- cases, 28 were M-rosette+; and of 22 M-rosette-cases, 18 were SIg+. By combining results of the two assays and accepting positivity of either one or both as sufficient for diagnosis, B-CLL was diagnosed in 163 cases (97.60%). CD5 was performed in 49 cases of the 167 with paired data for SIg and M-rosettes. By combining the results of the three assays and accepting positivity of any two or all three as sufficient for diagnosis, all 49 cases (100%) were diagnosed. Correlation analysis showed no significant association between M-rosette, SIg, and CD5 expression. The results demonstrate the independent expression of the three markers, and their complementary role in immunophenotyping B-CLL. In RLC, all 119 cases were T-lineage and SIg-, and 115 were M-rosette-, indicating the role of the two markers in differentiating B-CLL from RLC. Three of the four M-rosette+ T-RLC were subsequently diagnosed as B-CLL, suggesting the necessity of follow-up of such cases.
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388
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Shen B, Shang L, Shi X. [Necessity of family planning among the nationalities in view of the population structure in the Hui minority in Ningxia]. REN KOU XUE KAN (CHANGCHUN SHI, CHINA) 1991:37-42. [PMID: 12285485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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389
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Skarpeid HJ, Zimmer TL, Shen B, von Döhren H. The proline-activating activity of the multienzyme gramicidin S synthetase 2 can be recovered on a 115-kDa tryptic fragment. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 187:627-33. [PMID: 2303057 DOI: 10.1111/j.1432-1033.1990.tb15346.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The multienzyme gramicidin S synthetase 2 was treated with trypsin to obtain fragments capable of activating proline. Three different active fragments were detected. The course of proteolysis was simulated by using a concentration range of trypsin; the cleavage pattern indicated that one of the fragments was particularly stable. This fragment was purified and shown to have a molecular mass of 115 kDa. It was compared chromatographically, by SDS/PAGE, and enzymatically to a Pro-activating fragment produced by a gramicidin-S-negative mutant. It can be concluded that the proteolytic fragment represents a structure which is contained on a continuous part of the polypeptide chain of gramicidin S synthetase 2 and has a relatively compact structure. This provides evidence that the multienzyme gramicidin S synthetase 2 is, at least in part, constructed from functional domains. An approach towards extending these studies to other parts of the gramicidin S synthetase 2 molecule has also been devised. This work complements recombinant DNA studies in the area, providing stable functional fragments.
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390
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Lu HZ, Shen B, Wu XZ. [Role of endoscopic sphincterotomy in diseases of the biliary tract]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1987; 25:469-71, 501-2. [PMID: 3691255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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391
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Zhang X, Shen B. [[Developing cities of medium size and urbanization]]. REN KOU YAN JIU = RENKOU YANJIU 1987:19-22. [PMID: 12282751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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392
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Lu HZ, Shen B, Wu XZ. [Traditional Chinese medicine and western medicine non-operative treatment by endoscopic sphincterotomy in choledocholithiasis. A report of 115 cases]. ZHONG XI YI JIE HE ZA ZHI = CHINESE JOURNAL OF MODERN DEVELOPMENTS IN TRADITIONAL MEDICINE 1986; 6:728-9, 709. [PMID: 2951024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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393
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Yamamoto K, Byrne R, Edelstein C, Shen B, Scanu AM. In vitro effect of Triton WR-1339 on canine plasma high density lipoproteins. J Lipid Res 1984; 25:770-9. [PMID: 6491522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
We studied the effect in vitro of various concentrations of Triton WR-1339 on normolipidemic canine plasma and on the high density lipoproteins (HDL) isolated from this plasma by ultracentrifugation. As a preamble to this study, we established that Triton WR-1339 has a unimer molecular weight of 4,500, a micellar molecular weight of 180,000, and a critical micellar concentration (CMC) of 0.018 mM or 0.008 g/dl. Above its CMC, Triton WR-1339 in concentrations between 2 and 10 mg/ml induced concentration-dependent structural changes in HDL which were characterized by a progressive displacement of apoA-I from the HDL surface without loss of lipids. The addition of Triton WR-1339 to the HDL particles modified their electrophoresis mobility and caused an increase in size (95 +/- 5 A to 114 +/- 7 A). At the extreme Triton WR-1339 concentrations utilized in these studies (10 mg/ml) disruption of the HDL particles occurred; at this stage, the original, relatively homogeneous, spherical HDL particles were replaced by a heterogeneous population ranging in size between 50 and 250 A, representing complexes of Triton WR-1339 with lipids essentially free of apoA-I which could be sedimented by ultracentrifugation. The effects of Triton WR-1339 on whole plasma or isolated HDL were comparable. These studies indicate that Triton WR-1339 in vitro alters HDL in a concentration-dependent manner and that these changes vary from a displacement of apoA-I from the HDL surface to a state where all lipids are solubilized into the Triton WR-1339 micellar phase and are driven away from the protein moiety.(ABSTRACT TRUNCATED AT 250 WORDS)
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394
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Yamamoto K, Byrne R, Edelstein C, Shen B, Scanu AM. In vitro effect of Triton WR-1339 on canine plasma high density lipoproteins. J Lipid Res 1984. [DOI: 10.1016/s0022-2275(20)37740-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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395
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Yamamoto K, Shen B, Zarins C, Scanu AM. In vitro and in vivo interactions of Triton 1339 with plasma lipoproteins of normolipidemic rhesus monkeys. Preferential effects on high density lipoproteins. ARTERIOSCLEROSIS (DALLAS, TEX.) 1984; 4:418-34. [PMID: 6431955 DOI: 10.1161/01.atv.4.4.418] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Triton WR-1339 was incubated in vitro in various proportions with plasma from normolipidemic rhesus monkeys or with ultracentrifugally purified lipoproteins, and the products were examined by isopycnic density gradient ultracentrifugation, agarose column chromatography, electrophoretic and immunochemical techniques, and electron microscopy. Some experiments used apo A-I, apo A-II, or Triton labeled with either 125I or 131I. At concentrations of less than 10 mg/ml plasma, Triton interacted preferentially with HDL, changing lipoprotein size and density; Triton was progressively incorporated into the HDL particles, displacing apo E, apo A-I, and apo A-II. At concentrations above 10 mg/ml plasma, Triton displaced all apo A-I from the particle, and much lipid was dissolved into the Triton micelles. When Triton-treated HDL particles were used as a substrate for the enzyme LCAT, enzyme activity decreased in parallel to the displacement of apo A-I. There was no displacement of apo B from LDL nor any loss of lipids; but the particles became deformed and formed rouleaux. A single intravenous dose of Triton WR-1339 administered to a normolipidemic monkey (N) and to a hypercholesterolemic monkey (H) resulted in concentration-dependent HDL changes similar to those observed in vitro. LDL was less affected by Triton, with changes occurring only at high doses. After these structural changes, intravenously injected 131I apo A-I disappeared rapidly from the circulation; 125I apo A-II disappeared less rapidly. These increased clearances were accompanied by a drop in apo A-I plasma levels and the disappearance of HDL particles from plasma. The lipoprotein and apolipoprotein patterns returned to normal 14 days after Triton. We conclude that Triton WR-1339, when exposed to rhesus plasma in vitro or in vivo, interacts preferentially with HDL in a dose-dependent manner. At low concentrations, Triton acts on surface components of the HDL particle; at higher concentrations, Triton penetrates the particle, causing structural disruption. Because of its high affinity for HDL, Triton WR-1339 is a useful reagent for study of HDL structure-function relationships.
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