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Li B, Hartono C, Ding R, Sharma VK, Ramaswamy R, Qian B, Serur D, Mouradian J, Schwartz JE, Suthanthiran M. Noninvasive diagnosis of renal-allograft rejection by measurement of messenger RNA for perforin and granzyme B in urine. N Engl J Med 2001; 344:947-54. [PMID: 11274620 DOI: 10.1056/nejm200103293441301] [Citation(s) in RCA: 469] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Acute rejection is a serious and frequent complication of renal transplantation, and its diagnosis is contingent on the invasive procedure of allograft biopsy. A noninvasive diagnostic test for rejection could improve the outcome of transplantation. METHODS We obtained 24 urine specimens from 22 renal-allograft recipients with a biopsy-confirmed episode of acute rejection and 127 samples from 63 recipients without evidence of acute rejection. RNA was isolated from the urinary cells. Messenger RNA (mRNA) encoding the cytotoxic proteins perforin and granzyme B and a constitutively expressed cyclophilin B gene were measured with the use of a competitive, quantitative polymerase chain reaction, and the level of expression was correlated with allograft status. RESULTS The log-transformed mean (+/-SE) levels of perforin mRNA and granzyme B mRNA, which encode cytotoxic proteins, but not the levels of constitutively expressed cyclophiiin B mRNA, were higher in the urinary cells from the 22 patients with a biopsy-confirmed episode of acute rejection than in the 63 recipients without an episode of acute rejection (perforin, 1.4+/-0.3 vs. -0.6+/-0.2 fg per microgram of total RNA; P<0.001; and granzyme B, 1.2+/-0.3 vs. -0.9+/-0.2 fg per microgram of total RNA; P<0.001). Analysis involving the receiver-operating-characteristic curve demonstrated that acute rejection can be predicted with a sensitivity of 83 percent and a specificity of 83 percent with the use of a cutoff value of 0.9 fg of perforin mRNA per microgram of total RNA, and with a sensitivity of 79 percent and a specificity of 77 percent with the use of a cutoff value of 0.4 fg of granzyme B mRNA per microgram of total RNA. Sequential urine samples were obtained from 37 patients during the first nine days after transplantation; and measurements of the levels of mRNA that encoded cytotoxic proteins identified those in whom acute rejection developed. CONCLUSIONS Measurement of mRNA encoding cytotoxic proteins in urinary cells offers a noninvasive means of diagnosing acute rejection of renal allografts.
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Evaluation Study |
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Abstract
Spindle microtubules (MTs) in PtK1 cells, fixed at stages from metaphase to telophase, have been reconstructed using serial sections, electron microscopy, and computer image processing. We have studied the class of MTs that form an interdigitating system connecting the two spindle poles (interpolar MTs or ipMTs) and their relationship to the spindle MTs that attach to kinetochores (kMTs). Viewed in cross section, the ipMTs cluster with antiparallel near neighbors throughout mitosis; this bundling becomes much more pronounced as anaphase proceeds. While the minus ends of most kMTs are near the poles, those of the ipMTs are spread over half of the spindle length, with at least 50% lying > 1.5 microns from the poles. Longitudinal views of the ipMT bundles demonstrate a major rearrangement of their plus ends between mid- and late anaphase B. However, the minus ends of these MTs do not move appreciably farther from the spindle midplane, suggesting that sliding of these MTs contributes little to anaphase B. The minus ends of ipMTs are markedly clustered in the bundles of kMTs throughout anaphase A. These ends lie close to kMTs much more frequently than would be expected by chance, suggesting a specific interaction. As sister kinetochores separate and kMTs shorten, the minus ends of the kMTs remain associated with the spindle poles, but the minus ends of many ipMTs are released from the kMT bundles, allowing the spindle pole and the kMTs to move away from the ipMTs as the spindle elongates.
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research-article |
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Ding R, McDonald KL, McIntosh JR. Three-dimensional reconstruction and analysis of mitotic spindles from the yeast, Schizosaccharomyces pombe. J Cell Biol 1993; 120:141-51. [PMID: 8416984 PMCID: PMC2119489 DOI: 10.1083/jcb.120.1.141] [Citation(s) in RCA: 253] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Mitotic spindles of Schizosaccharomyces pombe have been studied by EM, using serial cross sections to reconstruct 12 spindles from cells that were ultrarapidly frozen and fixed by freeze substitution. The resulting distributions of microtubules (MTs) have been analyzed by computer. Short spindles contain two kinds of MTs: continuous ones that run from pole to pole and MTs that originate at one pole and end in the body of the spindle. Among the latter there are three pairs of MT bundles that end on fibrous, darkly staining structures that we interpret as kinetochores. The number of MTs ending at each putative kinetochore ranges from two to four; all kinetochore-associated MTs disappear as the spindle elongates from 3-6 microns. At this and greater spindle lengths, there are no continuous MTs, only polar MTs that interdigitate at the spindle midzone, but the spindle continues to elongate. An analysis of the density of neighboring MTs at the midzone of long spindles shows that their most common spacing is approximately 40 nm, center to center, and that there is a preferred angular separation of 90 degrees. Only hints of such square-packing are found at the midzone of short spindles, and near the poles there is no apparent order at any mitotic stage. Our data suggest that the kinetochore MTs (KMTs) do not interact directly with nonkinetochore MTs, but that interdigitating MTs from the two spindle poles do interact to form a mechanically stable bundle that connects the poles. As the spindle elongates, the number of MTs decreases while the mean length of the MTs that remain increases. We conclude that the chromosomes of S. pombe become attached to the spindle by kinetochore MTs, that these MTs disappear as the chromosomes segregate, that increased separation of daughter nuclei is accompanied by a sliding apart of anti-parallel MTs, and that the mitotic processes of S. pombe are much like those in other eukaryotic cells.
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research-article |
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Asada H, Kawamura Y, Maruyama K, Kume H, Ding R, Ji FY, Kanbara N, Kuzume H, Sanbo M, Yagi T, Obata K. Mice lacking the 65 kDa isoform of glutamic acid decarboxylase (GAD65) maintain normal levels of GAD67 and GABA in their brains but are susceptible to seizures. Biochem Biophys Res Commun 1996; 229:891-5. [PMID: 8954991 DOI: 10.1006/bbrc.1996.1898] [Citation(s) in RCA: 247] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The gene encoding of the 65 kDa isoform of the gamma-aminobutyric acid (GABA)-synthesizing enzyme, glutamic acid decarboxylase (GAD), GAD65, was targeted in mice by homologous recombination. Viable GAD65 -/- mice were obtained with the expected mendelian frequency and displayed no gross morphological defects. Despite the complete loss of GAD65 mRNA and protein in a homozygous mutant, there was no difference in GABA content in the brains of GAD65 +/+, +/-, and -/- mice. As for the other 67 kDa isoform (GAD67), the levels of mRNA and protein were largely unchanged by the GAD65 mutation. General behavior, including locomotor activity and performance in the Morris water maze task, appeared normal, but seizures were more easily induced by picrotoxin and pentylenetetrazol: the latencies to seizures induced by picrotoxin were shorter and the dose of pentylenetetrazol required for induction of seizures was lower.
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Ding R, West RR, Morphew DM, Oakley BR, McIntosh JR. The spindle pole body of Schizosaccharomyces pombe enters and leaves the nuclear envelope as the cell cycle proceeds. Mol Biol Cell 1997; 8:1461-79. [PMID: 9285819 PMCID: PMC276170 DOI: 10.1091/mbc.8.8.1461] [Citation(s) in RCA: 193] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The cycle of spindle pole body (SPB) duplication, differentiation, and segregation in Schizosaccharomyces pombe is different from that in some other yeasts. Like the centrosome of vertebrate cells, the SPB of S. pombe spends most of interphase in the cytoplasm, immediately next to the nuclear envelope. Some gamma-tubulin is localized on the SPB, suggesting that it plays a role in the organization of interphase microtubules (MTs), and serial sections demonstrate that some interphase MTs end on or very near to the SPB. gamma-Tubulin is also found on osmiophilic material that lies near the inner surface of the nuclear envelope, immediately adjacent to the SPB, even though there are no MTs in the interphase nucleus. Apparently, the MT initiation activities of gamma-tubulin in S. pombe are regulated. The SPB duplicates in the cytoplasm during late G2 phase, and the two resulting structures are connected by a darkly staining bridge until the mitotic spindle forms. As the cell enters mitosis, the nuclear envelope invaginates beside the SPB, forming a pocket of cytoplasm that accumulates dark amorphous material. The nuclear envelope then opens to form a fenestra, and the duplicated SPB settles into it. Each part of the SPB initiates intranuclear MTs, and then the two structures separate to lie in distinct fenestrae as a bipolar spindle forms. Through metaphase, the SPBs remain in their fenestrae, bound to the polar ends of spindle MTs; at about this time, a small bundle of cytoplasmic MTs forms in association with each SPB. These MTs are situated with one end near to, but not on, the SPBs, and they project into the cytoplasm at an orientation that is oblique to the simple axis. As anaphase proceeds, the nuclear fenestrae close, and the SPBs are extruded back into the cytoplasm. These observations define new fields of enquiry about the control of SPB duplication and the dynamics of the nuclear envelope.
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Shin GT, Khanna A, Ding R, Sharma VK, Lagman M, Li B, Suthanthiran M. In vivo expression of transforming growth factor-beta1 in humans: stimulation by cyclosporine. Transplantation 1998; 65:313-8. [PMID: 9484745 DOI: 10.1097/00007890-199802150-00003] [Citation(s) in RCA: 148] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Transforming growth factor-beta1 (TGF-beta1) is an immunoregulatory and fibrogenic cytokine. In an earlier in vitro study, we demonstrated that cyclosporine (CsA) increases TGF-beta1 transcription rate in human T lymphocytes. Herein, we explored whether CsA augments the in vivo expression of TGF-beta1 in humans. METHODS The inherent difficulty in studying the in vivo effect of CsA in humans was circumvented by investigating stable end-stage renal disease patients who were preconditioned with CsA before their living donor renal transplantation. Sera and peripheral blood mononuclear cells were obtained from CsA-preconditioned patients and quantified for TGF-beta1 expression at the mRNA (by competitive polymerase chain reaction) and protein (sandwich enzyme-linked immunosorbent assay) levels. RESULTS Our studies demonstrated a significant increase in TGF-beta1 expression after CsA therapy. The stimulatory effect was unique to TGF-beta1, and CsA did not increase interleukin (IL)-10, IL-6, IL-2, or tumor necrosis factor-alpha expression. CONCLUSIONS Our first-time demonstration of a TGF-beta1-selective in vivo stimulatory effect of CsA in humans: (1) advances a TGF-beta1-centered hypothesis for the beneficial (immunosuppression) and detrimental (fibrosis, hypertension) effects of CsA use, and (2) broadens the mechanism of immunosuppressive action of CsA to include heightened expression of an endogenous immunosuppressive cytokine.
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West RR, Vaisberg EV, Ding R, Nurse P, McIntosh JR. cut11(+): A gene required for cell cycle-dependent spindle pole body anchoring in the nuclear envelope and bipolar spindle formation in Schizosaccharomyces pombe. Mol Biol Cell 1998; 9:2839-55. [PMID: 9763447 PMCID: PMC25557 DOI: 10.1091/mbc.9.10.2839] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/1998] [Accepted: 07/24/1998] [Indexed: 11/11/2022] Open
Abstract
The "cut" mutants of Schizosaccharomyces pombe are defective in spindle formation and/or chromosome segregation, but they proceed through the cell cycle, resulting in lethality. Analysis of temperature-sensitive alleles of cut11(+) suggests that this gene is required for the formation of a functional bipolar spindle. Defective spindle structure was revealed with fluorescent probes for tubulin and DNA. Three-dimensional reconstruction of mutant spindles by serial sectioning and electron microscopy showed that the spindle pole bodies (SPBs) either failed to complete normal duplication or were free floating in the nucleoplasm. Localization of Cut11p tagged with the green fluorescent protein showed punctate nuclear envelope staining throughout the cell cycle and SPBs staining from early prophase to mid anaphase. This SPB localization correlates with the time in the cell cycle when SPBs are inserted into the nuclear envelope. Immunoelectron microscopy confirmed the localization of Cut11p to mitotic SPBs and nuclear pore complexes. Cloning and sequencing showed that cut11(+) encodes a novel protein with seven putative membrane-spanning domains and homology to the Saccharomyces cerevisiae gene NDC1. These data suggest that Cut11p associates with nuclear pore complexes and mitotic SPBs as an anchor in the nuclear envelope; this role is essential for mitosis.
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research-article |
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Ding R, Pommier Y, Kang V, Smulson M. Depletion of poly(ADP-ribose) polymerase by antisense RNA expression results in a delay in DNA strand break rejoining. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42347-2] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Kleanthous H, Myers GA, Georgakopoulos KM, Tibbitts TJ, Ingrassia JW, Gray HL, Ding R, Zhang ZZ, Lei W, Nichols R, Lee CK, Ermak TH, Monath TP. Rectal and intranasal immunizations with recombinant urease induce distinct local and serum immune responses in mice and protect against Helicobacter pylori infection. Infect Immun 1998; 66:2879-86. [PMID: 9596763 PMCID: PMC108285 DOI: 10.1128/iai.66.6.2879-2886.1998] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/1997] [Accepted: 03/12/1998] [Indexed: 02/07/2023] Open
Abstract
To determine the optimal inductive sites for immunization against Helicobacter pylori infection, the protective efficacy of recombinant urease (rUre) was assessed for mice given the vaccine by either the oral (p.o.), intranasal (i.n.), or rectal route. When mice were immunized with rUre (25 microg p.o. or rectally or 10 microg i.n.) plus heat-labile toxin from Escherichia coli as the mucosal adjuvant, all routes afforded protection against challenge with H. pylori, as indicated by a significant reduction in gastric urease activity (P < 0.0005) compared to that of sham-immunized controls. Quantitative H. pylori culture of stomach tissue demonstrated a >97% reduction in bacterial burden in mice immunized by all routes (P < 0.05). Induction of antiurease immunoglobulin A (IgA) levels in gastric luminal secretions after p.o. immunization was greater than after i.n. administration (means, 6.0 and 1.02 ng/ml, respectively) and was dependent upon challenge with H. pylori. However, immunization by the rectal route resulted in the generation of the highest levels of gastric antiurease IgA (mean, 40. 89 ng/ml), which was detectable prior to challenge with H. pylori. Immunohistochemical staining of stomach tissue for cells secreting urease-specific antibody and CD4(+) T cells showed levels of recruitment to be dependent upon challenge with H. pylori and equivalent for all routes. These results identify both the rectum and nasal passages as suitable inductive sites for urease immunization.
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Comparative Study |
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Abstract
This is a retrospective study of 378 consecutive stroke patients who were referred between June 1994 and June 1997 for videofluorographic study of oropharyngeal swallow. Patients who had radiation therapy, brain tumor, brain surgery, head and/or spinal cord trauma, oral-pharyngeal disease or surgery, or other neurologic diseases in addition to the stroke were excluded from the study. Patients were assigned to two groups: one with pneumonia and one without pneumonia. One hundred one patients were included in the pneumonia group, and 277 patients were included in the nonpneumonia group. Within the pneumonia group, patients were assigned to an acute pneumonia group (pneumonia within 6 months poststroke) and a chronic pneumonia group (pneumonia more than 6 months poststroke). Variables examined in the study included patients' medical history and the findings from the videofluorographic studies. Pearson chi-square analysis was used to identify those variables that were significantly different between the pneumonia and nonpneumonia patient groups and between the acute and chronic pneumonia groups. Results showed that stroke patients who developed pneumonia had a significantly higher incidence of multiple-location and unspecified lesion strokes, chronic airway disease in their medical history, and aspiration during the videofluorographic studies when compared with patients who did not develop pneumonia. Within the pneumonia group, the acute pneumonia group was found to have a significantly higher incidence of hypertension and diabetes in their medical history and a significantly higher incidence of aspiration and reduced laryngeal elevation during the videofluorographic studies. Between 48% and 55% of all stroke patients in the study aspirated. Patients who suffered multiple strokes, brainstem stroke, or subcortical stroke had the greatest frequency of aspiration.
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Comparative Study |
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85 |
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Ding R, Leonov AI, Coran AY. A Study of the Vulcanization Kinetics of an Accelerated-Sulfur SBR Compound. RUBBER CHEMISTRY AND TECHNOLOGY 1996. [DOI: 10.5254/1.3538360] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
Vulcanization kinetics for a SBR compound was studied by using both curemeter and DSC methods by a kinetic approach. A simplified but realistic model reaction scheme was used to simulate both induction and curing periods simultaneously. Model parameters were extracted from isothermal curemeter experiments. The model prediction demonstrated a good agreement with isothermal curemeter data over a temperature range of 120°C to 180°C. The variation of equilibrium modulus with temperature, observed from cure curves, can also be predicted. However, DSC experiments showed a different reaction behavior in the curing period as compared to model calculations. This was explained by the assumption that the reaction heat observed in DSC is due to all possible exothermal reactions, and the formation of crosslinks is only a part of these reactions. Hence, the curemeter can provide a good indication of crosslink formation, while DSC displays the entire reaction heat released during the vulcanization process. The kinetic approach allows one to incorporate vulcanization kinetics into the practical simulation of reactive processing operations.
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Streshinsky M, Ding R, Liu Y, Novack A, Galland C, Lim AEJ, Guo-Qiang Lo P, Baehr-Jones T, Hochberg M. The Road to Affordable, Large-Scale Silicon Photonics. ACTA ACUST UNITED AC 2013. [DOI: 10.1364/opn.24.9.000032] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Rosenthal DS, Ding R, Simbulan-Rosenthal CM, Vaillancourt JP, Nicholson DW, Smulson M. Intact cell evidence for the early synthesis, and subsequent late apopain-mediated suppression, of poly(ADP-ribose) during apoptosis. Exp Cell Res 1997; 232:313-21. [PMID: 9168807 DOI: 10.1006/excr.1997.3536] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Poly(ADP-ribose) polymerase (PARP), which is catalytically activated by DNA strand breaks, has been implicated in apoptosis, or programmed cell death. A protease (CPP32) responsible for the cleavage of PARP and necessary for apoptosis was recently purified and characterized. The coordinated sequence of events related to PARP activation and cleavage in apoptosis has now been examined in individual cells. Apoptosis was studied in a human osteosarcoma cell line that undergoes a slow (8 to 10 days), spontaneous, and reproducible death program in culture. Changes in the abundance of intact PARP, poly(ADP-ribose) (PAR), and a proteolytic cleavage product of PARP that contains the DNA-binding domain were examined during apoptosis in the context of individual, whole cells by immunofluorescence with specific antibodies. The synthesis of PAR from NAD increased early, within 2 days of cell plating for apoptosis, prior to the appearance of internucleosomal DNA cleavage and before the cells become irreversibly committed to apoptosis, since replating yields viable, nonapoptotic cells. Strong expression of full-length PARP was also detected, by immunofluorescence as well as by Western analysis, during this same time period. However, after approximately 4 days in culture, the abundance of both full-length PARP and PAR decreased markedly. After 6 days, a proteolytic cleavage product containing the DNA-binding domain of PARP was detected immunocytochemically and confirmed by Western analysis, both in the nuclei and in the cytoplasm of cells. A recombinant peptide spanning the DNA-binding domain of PARP was expressed, purified, and biotinylated, and was then used as a probe for DNA strand breaks. Fluorescence microscopy with this probe revealed extensive DNA fragmentation during the later stages of apoptosis. This is the first report, using individual, intact cells, demonstrating that poly(ADP-ribosyl)ation of nuclear proteins occurs prior to the commitment to apoptosis, that inactivation and cleavage of PARP begin shortly thereafter, and that very little PAR per se is present during the later stages of apoptosis, despite the presence of a very large number of DNA strand breaks. These results suggest a negative regulatory role for PARP during apoptosis, which in turn may reflect the requirement for adequate NAD and ATP during the later stages of programmed cell death.
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Ermak TH, Ding R, Ekstein B, Hill J, Myers GA, Lee CK, Pappo J, Kleanthous HK, Monath TP. Gastritis in urease-immunized mice after Helicobacter felis challenge may be due to residual bacteria. Gastroenterology 1997; 113:1118-28. [PMID: 9322506 DOI: 10.1053/gast.1997.v113.pm9322506] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND & AIMS Oral immunization with recombinant Helicobacter pylori urease (rUre) coadministered with a mucosal adjuvant protects mice against challenge with Helicobacter felis. In this study, the duration of protection and gastritis after challenge were characterized at sequential time intervals up to 1 year. METHODS Outbred Swiss-Webster mice were orally immunized with rUre plus adjuvant and examined for the presence of H. felis infection and leukocyte infiltration into the gastric mucosa. RESULTS When defined by gastric urease activity, 70%-95% of rUre-immunized mice were protected for between 2 and 57 weeks. Challenge with H. felis increased the inflammatory response in the gastric mucosa of rUre-immunized mice, which also had elevated CD4+ and CD8+ T cells. The CD8+ cells represented a population of gastric intraepithelial cells, which expressed the mucosal alpha E-integrin. Epithelial changes consisting of parietal cell loss and hyperplasia of the epithelium occurred in approximately 20% of the mice. Antimicrobial triple therapy significantly decreased the degree of gastritis and epithelial alteration in the stomach. CONCLUSIONS These results indicate that oral immunization of mice with rUre produces a long-lasting inhibition of H. felis infection but that residual bacteria may produce a persistent lymphocytic infiltration under these experimental conditions.
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Smulson ME, Kang VH, Ntambi JM, Rosenthal DS, Ding R, Simbulan CM. Requirement for the expression of poly(ADP-ribose) polymerase during the early stages of differentiation of 3T3-L1 preadipocytes, as studied by antisense RNA induction. J Biol Chem 1995; 270:119-27. [PMID: 7814362 DOI: 10.1074/jbc.270.1.119] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Poly(ADP-ribose) polymerase (PADPRP) is biologically significant in the rejoining of DNA strand breaks. Post confluent cultures of 3T3-L1 preadipocytes showed marked increases in PADPRP protein and activity when the cells were induced to differentiate into adipocytes. When this increase in PADPRP expression was prevented in stably transfected 3T3-L1 cells by induction of PADPRP antisense RNA synthesis, the cells did not differentiate nor undergo the two or three rounds of DNA replication that are required for initiation of the differentiation process. 3T3-L1 cells expressing PADPRP antisense RNA under differentiation conditions were easily detached from plates and in some cases eventually died. When newly expressed PADPRP protein and DNA synthesis was assessed in cells at zero time or at 24 h after induction of differentiation by incorporation of bromodeoxyuridine or [3H]thymidine into DNA, significant incorporation was shown to occur in control cells after 24 h, but not in antisense cells. Furthermore, during the first 24 h, the co-immunoprecipitation of PADPRP and DNA polymerase alpha was observed in control cells, whereas no such complex formation was noted in the induced antisense cells, nor in uninduced control cells.
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Ding R, Asada H, Obata K. Changes in extracellular glutamate and GABA levels in the hippocampal CA3 and CA1 areas and the induction of glutamic acid decarboxylase-67 in dentate granule cells of rats treated with kainic acid. Brain Res 1998; 800:105-13. [PMID: 9685600 DOI: 10.1016/s0006-8993(98)00507-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
For the evaluation of glutamatergic and GABAergic transmission during seizures, rat hippocampal CA1 and CA3 areas were separately assessed by brain microdialysis, and extracelluar glutamate and GABA were measured through the course of the seizures after a systemic administration of kainic acid (KA). The generalized convulsion started at about 1.5 h and was suppressed by diazepam at 2 h after the KA treatment. In the CA3 area, extracellular glutamate started to increase soon after the KA injection and returned to the control level at about 1.5 h. A decrease and then slight increase of the extracellular glutamate level in CA3 followed the diazepam injection. In the CA1 area, in contrast, a long-lasting decrease of extracellular glutamate was observed. The extracellular GABA concentration in the CA3 area increased immediately after the systemic administration of KA and returned to the normal level at about 3.5 h. A second increase in the extracellular GABA in this area began at about 4.5 h after the KA treatment. In the CA1 area, an increase of extracellular GABA began at about 3.5 h after KA administration (much later than that observed in the CA3 area) and was maintained throughout the observation. In situ hybridization showed a transient expression of glutamic acid decarboxylase (GAD)-67 mRNA in the granule cell layer of the dentate gyrus at 4 and 6 h, whereas GAD65 mRNA was unaffected. GABA immunoreactivity in the same area and mossy fibers in the CA3 were increased most significantly at 8 h after administration of KA. The possible relation of GABA induction in mossy fibers with the delayed increase in extracellular GABA in CA3 was discussed.
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Ding R, Jansen JK, Laing NG, Tønnesen H. The innervation of skeletal muscles in chickens curarized during early development. JOURNAL OF NEUROCYTOLOGY 1983; 12:887-919. [PMID: 6319617 DOI: 10.1007/bf01153341] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Chicken embryos were treated with partially paralysing doses of d-tubocurarine (dtc) from embryonic (E) days 6 to 10. The pattern of innervation of the lateral gastrocnemius (GL) muscle was examined both morphologically and physiologically just before hatching on day E20 or E21. There was a 70% increase in number of surviving motor neurons in the lateral motor column and a 50% increase in the number of myelinated axons in the nerve to GL. The GL muscle was significantly atrophic, with an average weight of 40% of normal. The atrophy was largely due to the reduced size of the muscle fibres. The mean size of the motor units was essentially unchanged or perhaps slightly increased. There was a striking increase in the level of polyneuronal innervation of the muscle fibres, both in terms of number of synaptic sites per fibre and number of axons innervating each site. Spontaneous miniature endplate potentials (mepps) indicated focal innervation of the fibres in the normal muscle. Most fibres in the dtc-treated muscles had mepps of widely varying time courses, and there was no simple relation between amplitude and rise time. Many of the slow mepps were not represented in the endplate potentials evoked by nerve stimulation. The quantal content of the endplate potential (epp) was generally increased in the dtc-treated muscles. The findings are discussed in terms of a retrograde signal from muscle to nerve and its dependence on muscle activity.
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Rubinchik S, Ding R, Qiu AJ, Zhang F, Dong J. Adenoviral vector which delivers FasL-GFP fusion protein regulated by the tet-inducible expression system. Gene Ther 2000; 7:875-85. [PMID: 10845726 DOI: 10.1038/sj.gt.3301172] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Fas ligand (FasL) is a member of the tumor necrosis family and when bound to its receptor, Fas, induces apoptosis. It plays important roles in immune response, degenerative and lymphoproliferative diseases, development and tumorigenesis. It is also involved in generation of immune privilege sites in the eye and testis. Harnessing the power of this molecule is expected to lead to a powerful chemotherapeutic. We describe the construction and characterization of replication-deficient adenoviral vectors that express a fusion of murine FasL and green fluorescent protein (GFP). FasL-GFP retains full activity of wild-type FasL, at the same time allowing for easy visualization and quantification in both living and fixed cells. The fusion protein is under the control of a tetracycline-regulated gene expression system. Tight control of expression is achieved by creating a novel 'double recombinant' Ad vector, in which the tet-responsive element and the transactivator element are built into the opposite ends of the same vector to avoid enhancer interference. Expression can be conveniently regulated by tetracycline or its derivatives in a dose-dependent manner. The vector was able to deliver FasL-GFP gene to cells in vitro efficiently, and the expression level and function of the fusion protein was modulated by the concentration of doxycycline. This regulation allows us to produce high titers of the vector by inhibiting FasL expression in an apoptosis-resistant cell line. Induction of apoptosis was demonstrated in all cell lines tested. These results indicate that our vector is a potentially valuable tool for FasL-based gene therapy of cancer and for the study of FasL/Fas-mediated apoptosis and immune privilege.
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Smulson M, Istock N, Ding R, Cherney B. Deletion mutants of poly(ADP-ribose) polymerase support a model of cyclic association and dissociation of enzyme from DNA ends during DNA repair. Biochemistry 1994; 33:6186-91. [PMID: 8193132 DOI: 10.1021/bi00186a018] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
With an in vitro DNA repair system, Satoh and Lindah [(1992) Nature 356, 356-358] demonstrated that unmodified poly(ADP-ribose) polymerase (PADPRP) binds to radiation-damaged DNA and inhibits repair in the absence of NAD. However, in the presence of NAD, PADPRP undergoes automodification and the DNA is repaired. It was hypothesized that PADPRP cycles between an unmodified form, which protects DNA breaks, and an automodified form, which is released from DNA, thereby allowing access to repair enzymes. We have now tested this model with bacterially expressed mutants of PADPRP with deletions in the three major functional domains of the enzyme [Cherney, B. W., Chaudry, B., Bhatia, K., Butt, T. R., & Smulson, M. E. (1991) Biochemistry 30, 10420-10427]. Deletion mutants with an intact amino-terminal DNA-binding domain, and therefore capable of binding to DNA strand breaks in the in vitro assay, inhibited repair; however, whether the deletion was in the NAD-binding, active site domain or the automodification domain, the inhibition of repair exerted by these mutant proteins was not alleviated by NAD. A PADPRP mutant with a deletion in the DNA-binding domain did not inhibit DNA repair. Thus, the behavior of these PADPRP deletion mutants is consistent with the model proposed earlier. The model was also supported by experiments with Manley extracts of HeLa cells stably transfected with a PADPRP antisense RNA construct. Extracts of cells induced to express antisense RNA did not markedly inhibit in vitro DNA repair, nor did the addition of NAD influence the assay. In contrast, noninduced cell extracts inhibited repair and inhibition was alleviated by NAD.(ABSTRACT TRUNCATED AT 250 WORDS)
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Tayrouz Y, Ganssmann B, Ding R, Klingmann A, Aderjan R, Burhenne J, Haefeli WE, Mikus G. Ritonavir increases loperamide plasma concentrations without evidence for P-glycoprotein involvement. Clin Pharmacol Ther 2001; 70:405-14. [PMID: 11719726 DOI: 10.1067/mcp.2001.119212] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND The antidiarrheal drug loperamide is frequently used to treat ritonavir-associated diarrhea in patients with human immunodeficiency virus. The absence of marked central opioid effects has been attributed to its low bioavailability and its poor penetration of the blood-brain barrier, both of which might be altered by ritonavir, a potent P-glycoprotein and cytochrome P4503A inhibitor. METHODS A 16-mg dose of loperamide was administered to 12 healthy male and female volunteers together with either 600 mg of ritonavir or placebo. Detailed pharmacokinetics of loperamide and its metabolites were determined over 72 hours. Central opioid effects were measured by evaluation of pupil diameter, cold pressor test, and transcutaneous PCO2 and PO2. RESULTS Ritonavir caused a major pharmacokinetic interaction, increasing the area under the concentration-time curve of loperamide from 104 +/- 60 h x pmol/ml after placebo to 276 +/- 68 h. pmol/ml and delayed formation of the major metabolite desmethylloperamide (time to reach maximum concentration after drug administration [t(max)], 7.1 +/- 2.6 hours versus 19.6 +/- 9.1 hours). The urinary metabolic ratio of loperamide increased 3 times whereas the total molar amount of loperamide and metabolites excreted in urine remained unchanged. No central pharmacodynamic effects were observed after coadministration of loperamide with either ritonavir or placebo. CONCLUSION This study demonstrates a major metabolic interaction probably by cytochrome P4503A4 with no evidence of P-glycoprotein involvement. This might explain the lack of central effects after ritonavir.
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Clinical Trial |
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Ding R, Feng L, He L, Chen Y, Wen P, Fu Z, Lin C, Yang S, Deng X, Zeng J, Sun G. Peroxynitrite decomposition catalyst prevents matrix metalloproteinase-9 activation and neurovascular injury after hemoglobin injection into the caudate nucleus of rats. Neuroscience 2015; 297:182-93. [PMID: 25849612 DOI: 10.1016/j.neuroscience.2015.03.065] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 03/19/2015] [Accepted: 03/29/2015] [Indexed: 10/23/2022]
Abstract
Hemoglobin (Hb) is a major constituent of blood and a potent mediator of oxidative or nitrative stress after intracerebral hemorrhage (ICH). Our previous study demonstrated that Hb could induce abundant peroxynitrite (ONOO(-)) formation in vivo, which may be involved in the blood-brain barrier (BBB) disruption, however, the drug intervention is absent and also the underlying mechanism. Using an experimental stroke model by injecting Hb into the caudate nucleus of male Sprague-Dawley rats, we assessed the role of ONOO(-) decomposition catalyst, 5,10,15,20-tetrakis (4-sulfonatophenyl) porphyrinato iron(III) [FeTPPS] in the activation of MMP-9 and Hb-induced neurovascular injuries. 3-Nitrotyrosine (3-NT, as an index of ONOO(-) formation) and NF-κB expression was measured by western blot (WB) and immunohistochemistry (IHC)/immunofluorescence (IF). Activity of MMP was evaluated by in situ zymography. Neurovascular injury was assessed using zonula occludens-1 (ZO-1) by WB and IF, fibronectin (FN) and neuron-specific nuclear protein (NeuN) IHC. Perihematomal cell death was determined by TUNEL assay. Behavioral outcome was measured by modified neurological severity score (mNSS) test. At the injured striata, profuse 3-NT was produced and mainly expressed in neutrophils and microglia/macrophages. 3-NT formation significantly colocalized with nuclear factor-κB (NF-κB) expression. In situ zymography showed that gelatinase activity was mostly co-localized with neurons and blood vessel walls and partly with neutrophils and microglia/macrophages. Enhanced 3-NT production, NF-κB induction and MMP-9 activation were obviously reduced after FeTPPS treatment. Hb-induced injury to tight junction protein (ZO-1), basal lamina of FN-immunopositive microvasculature and neural cells was evidently ameliorated by FeTPPS. In addition, apoptotic cell numbers as well as behavioral deficits were also improved. The present study shows that the administration of the ONOO(-) decomposition catalyst FeTPPS protects against Hb-induced neurovascular injuries and improves neurological function, which possibly in part by suppressing MMP-9 activation.
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Research Support, Non-U.S. Gov't |
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Hafner V, Jäger M, Matthée AK, Ding R, Burhenne J, Haefeli WE, Mikus G. Effect of simultaneous induction and inhibition of CYP3A by St John's Wort and ritonavir on CYP3A activity. Clin Pharmacol Ther 2009; 87:191-6. [PMID: 19924124 DOI: 10.1038/clpt.2009.206] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We aimed to assess the effect of coadministration and withdrawal of a potent cytochrome P450 3A (CYP3A) inhibitor (ritonavir) and a potent CYP3A inducer (St John's wort) on CYP3A enzyme activity in an open, fixed-sequence study design. We investigated the pharmacokinetics of midazolam: (i) at baseline, (ii) after a single dose of either St John's wort or ritonavir (each n = 6), (iii) after 14 days of coadministration of ritonavir (300 mg b.i.d.) and St John's wort (300 mg t.i.d.), and (iv) at 2 days after cessation of both St John's wort and ritonavir. Combined administration of inducer and inhibitor resulted in a predominance of enzyme inhibition: coadministration of St John's wort and ritonavir with intravenous administration of midazolam resulted in an increase in the area under the plasma concentration-time curve (AUC)(0-8 h) of midazolam to 180% of baseline value, whereas with orally administered midazolam, the AUC(0-6 h) increased to 412% of baseline value (P < 0.05 for each). After cessation of the coadministered drugs, the AUC(0-6 h) of orally administered midazolam decreased to 6% of the level observed during combined administration, and the AUC(0-8 h) of intravenously administered midazolam decreased to 33% of the values observed during combined administration (P < 0.001 for each). Induction may be unmasked after the withdrawal of a combination of a potent CYP3A inhibitor and a potent CYP3A inducer, leading to substantial drops in drug exposure of CYP3A substrates. This may require substantial dose adjustments, particularly of orally administered drugs.
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Randomized Controlled Trial |
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Medeiros M, Sharma VK, Ding R, Yamaji K, Li B, Muthukumar T, Valderde-Rosas S, Hernandez AM, Muñoz R, Suthanthiran M. Optimization of RNA yield, purity and mRNA copy number by treatment of urine cell pellets with RNAlater. J Immunol Methods 2003; 279:135-42. [PMID: 12969554 DOI: 10.1016/s0022-1759(03)00237-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND We have shown that measurement of mRNA for cytotoxic attack proteins perforin and granzyme B in urinary cells is a noninvasive means of diagnosing acute rejection of human renal allografts. Urinary cell mRNA studies have yielded useful information in other patient populations such as patients with cancer. The isolation of sufficient and high quality ribonucleic acid (RNA) from urinary cells however is problematic. RNAlater, an RNA stabilization solution, has been reported to optimize RNA isolation from tumor tissues stored at room temperature and from pigment-rich ocular tissues. METHODS We explored whether the addition of RNAlater to urine cell pellets improves RNA yield, enhances purity and facilitates measurement of low abundance mRNAs. We measured, with the use of real-time quantitative polymerase chain reaction (PCR) assay, levels of expression of a constitutively expressed gene 18S rRNA and mRNA for granzyme B and transforming growth factor-beta(1) (TGF-beta(1)) in urine specimens and renal biopsies obtained from renal allograft recipients. RESULTS RNA yield (P<0.01, Wilcoxon signed rank test) and the A260/A280 ratio (P<0.01) were both higher with urine cell pellets treated with RNAlater prior to snap freezing compared to cell pellets that were not treated with RNAlater prior to snap freezing. Levels (copy number per 1 microg of total RNA) of 18S rRNA (P<0.02), granzyme B mRNA (P=0.002) and TGF-beta(1) (P=0.02) were all higher with treated urine cell pellets compared to untreated cell pellets. Kruskall-Wallis one way analysis of variance and pair-wise comparisons with Student-Newman-Keuls test showed that the levels of mRNA for granzyme B (P<0.05) and TGF-beta(1) (P<0.05) are significantly different between renal allograft biopsies and untreated urine cell pellets but not between the biopsy specimens and RNAlater-treated urine cell pellets. CONCLUSIONS The addition of RNAlater to urine cell pellets improves RNA isolation from urinary cells and facilitates measurement of low abundance mRNAs.
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de Vries JX, Günthert W, Ding R. Determination of nicotinamide in human plasma and urine by ion-pair reversed-phase high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY 1980; 221:161-5. [PMID: 6450217 DOI: 10.1016/s0378-4347(00)81019-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Kou YB, Zhang SY, Zhao BL, Ding R, Liu H, Li S. Knockdown of MMP11 inhibits proliferation and invasion of gastric cancer cells. Int J Immunopathol Pharmacol 2013; 26:361-70. [PMID: 23755751 DOI: 10.1177/039463201302600209] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Matrix metalloproteinase 11 (MMP11 or stromelysin-3) has recently been reported to play a crucial role in the development and progression of multiple malignancies. The aim of this study was to investigate the function of MMP11 expression in human gastric adenocarcinoma (GAC). Using immunohistochemistry assay, we studied the expression level of MMP11 in GAC and adjacent non-cancerous tissues (ANCT). The association between MMP11 expression and tumor size and pathological grade, as well as metastatic potential was analyzed. Through small hairpin RNA (shRNA)-mediated MMP11 knockdown in SGC-7901 GAC cells, we observed the changes of the biological behaviors of GAC cells. Our results indicated that the rate of positive expression of MMP11 was higher in GAC tissues than in ANCT (55.0 vs 30.0 percent, P=0.025). MMP11 expression had no association with the factors of age or gender of the GAC patients, or the size, pathological staging and lymph node metastases of the tumors (each P greater than 0.05). Furthermore, MMP11 knockdown inhibited the proliferative activities and invasive potential of SGC-7901 GAC cells with decreased expression of IGF-1, PCNA and VEGF. Taken together, our findings demonstrated that MMP11 expression was increased in GAC tissues, but did not correlate with the clinicopathologic features. Knockdown of MMP11 expression could inhibit the proliferation and invasion of GAC cells probably through down-regulation of the IGF-1 signaling pathway, suggesting that MMP11 might be a potential therapeutic target for the treatment of gastric cancer.
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Journal Article |
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