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Berkley AJ, Xu H, Ramos RC, Gubrud MA, Strauch FW, Johnson PR, Anderson JR, Dragt AJ, Lobb CJ, Wellstood FC. Entangled macroscopic quantum States in two superconducting qubits. Science 2003; 300:1548-50. [PMID: 12750479 DOI: 10.1126/science.1084528] [Citation(s) in RCA: 372] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We present spectroscopic evidence for the creation of entangled macroscopic quantum states in two current-biased Josephson-junction qubits coupled by a capacitor. The individual junction bias currents are used to control the interaction between the qubits by tuning the energy level spacings of the junctions in and out of resonance with each other. Microwave spectroscopy in the 4 to 6 gigahertzrange at 20 millikelvin reveals energy levels that agree well with theoretical results for entangled states. The single qubits are spatially separate, and the entangled states extend over the 0.7-millimeter distance between the two qubits.
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Wakimoto H, Johnson PR, Knipe DM, Chiocca EA. Effects of innate immunity on herpes simplex virus and its ability to kill tumor cells. Gene Ther 2003; 10:983-90. [PMID: 12756419 DOI: 10.1038/sj.gt.3302038] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Several clinical trials have or are being performed testing the safety and efficacy of different strains of oncolytic viruses (OV) for malignant cancers. OVs represent either naturally occurring or genetically engineered strains of viruses that exhibit relatively selective replication in tumor cells. Several types of OV have been derived from herpes simplex virus 1 (HSV1). Tumor oncolysis depends on the processes of initial OV infection of tumor, followed by subsequent propagation of OV within the tumor itself. The role of the immune responses in these processes has not been extensively studied. On the contrary, effects of the immune response on the processes of wild-type HSV1 infection and propagation in the central nervous system have been studied and described in detail. The first line of defense against a wild-type HSV1 infection in both naive and immunized individuals is provided by innate humoral (complement, cytokines, chemokines) and cellular (macrophages, neutrophils, NK cells, gammadelta T cells, and interferon-producing cells) responses. These orchestrate the lysis of virions and virus-infected cells as well as provide a link to effective adaptive immunity. The role of innate defenses in curtailing the oncolytic effect of genetically engineered HSV has only recently been studied, but several of the same host responses appear to be operative in limiting anticancer effects by the replicating virus. The importance of this knowledge lies in finding avenues to modulate such initial innate responses, in order to allow for increased oncolysis of tumors while minimizing host toxicity.
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Johnson PR, Tepikin AV, Erdemli G. Role of mitochondria in Ca(2+) homeostasis of mouse pancreatic acinar cells. Cell Calcium 2002; 32:59-69. [PMID: 12161106 DOI: 10.1016/s0143-4160(02)00091-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The effects of mitochondrial Ca(2+) uptake on cytosolic Ca(2+) concentration ([Ca(2+)](c)) were investigated in mouse pancreatic acinar cells using cytosolic and/or mitochondrial Ca(2+) indicators. When calcium stores of the endoplasmic reticulum (ER) were emptied by prolonged incubation with thapsigargin (Tg) and acetylcholine (ACh), small amounts of calcium could be released into the cytosol (Delta[Ca(2+)](c)=46 +/- 6 nM, n=13) by applying mitochondrial inhibitors (combination of rotenone (R) and oligomycin (O)). However, applications of R/O, soon after the peak of Tg/Ach-induced Ca(2+) transient, produced a larger cytosolic calcium elevation (Delta[Ca(2+)](c)=84 +/- 6 nM, n=9), this corresponds to an increase in the total mitochondrial calcium concentration ([Ca(2+)](m)) by approximately 0.4 mM. In cells pre-treated with R/O or Ru360 (a specific blocker of mitochondrial Ca(2+) uniporter), the decay time-constant of the Tg/ACh-induced Ca(2+) response was prolonged by approximately 40 and 80%, respectively. Tests with the mitochondrial Ca(2+) indicator rhod-2 revealed large increases in [Ca(2+)](m) in response to Tg/ACh applications; this mitochondrial uptake was blocked by Ru360. In cells pre-treated with Ru360, 10nM ACh elicited large global increases in [Ca(2+)](c), compared to control cells in which ACh-induced Ca(2+) signals were localised in the apical region. We conclude that mitochondria are active elements of cellular Ca(2+) homeostasis in pancreatic acinar cells and directly modulate both local and global calcium signals induced by agonists.
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Morgan KT, Ni H, Brown HR, Yoon L, Qualls CW, Crosby LM, Reynolds R, Gaskill B, Anderson SP, Kepler TB, Brainard T, Liv N, Easton M, Merrill C, Creech D, Sprenger D, Conner G, Johnson PR, Fox T, Sartor M, Richard E, Kuruvilla S, Casey W, Benavides G. Application of cDNA microarray technology to in vitro toxicology and the selection of genes for a real-time RT-PCR-based screen for oxidative stress in Hep-G2 cells. Toxicol Pathol 2002; 30:435-51. [PMID: 12187936 DOI: 10.1080/01926230290105613] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2022]
Abstract
Large-scale analysis of gene expression using cDNA microarrays promises the rapid detection of the mode of toxicity for drugs and other chemicals. cDNA microarrays were used to examine chemically induced alterations of gene expression in HepG2 cells exposed to a diverse group of toxicants at an equitoxic exposure concentration. The treatments were ouabain (43 microM), lauryl sulfate (260 microM), dimethylsulfoxide (1.28 M), cycloheximide (62.5 microM), tolbutamide (12.8 mM), sodium fluoride (3 mM), diethyl maleate (1.25 mM), buthionine sulfoximine (30 mM), potassium bromate (2.5 mM), sodium selenite (30 microM), alloxan (130 mM), adriamycin (40 microM), hydrogen peroxide (4 mM), and heat stress (45 degrees C x 30 minutes). Patterns of gene expression were correlated with morphologic and biochemical indicators of toxicity. Gene expression responses were characteristically different for each treatment. Patterns of expression were consistent with cell cycle arrest, DNA damage, diminished protein synthesis, and oxidative stress. Based upon these results, we concluded that gene expression changes provide a useful indicator of oxidative stress, as assessed by the GSH:GSSG ratio. Under the conditions of this cell culture test system, oxidative stress upregulated 5 genes, HMOX1, p21(waf1/cip1), GCLM, GR, TXNR1 while downregulating CYP1A1 and TOPO2A. Primers and probes for these genes were incorporated into the design of a 7-gene plate for RT-PCR. The plate design permitted statistical analysis and allowed clear discrimination between chemicals inducing oxidative vs nonoxidative stress. A simple oxidative stress score (0-1), based on the responses by the 7 genes (including p-value) on the RT-PCR plate, was correlated with the GSH:GSSG ratio using linear regression and ranking (Pearson product) procedures. These analyses yielded correlation coefficients of 0.74 and 0.87, respectively, for the treatments tested (when 1 outlier was excluded), indicating a good correlation between the biochemical and transcriptional measures of oxidative stress. We conclude that it is essential to measure the mechanism of interest directly in the test system being used when assessing gene expression as a tool for toxicology. Tables 1-15, referenced in this paper, are not printed in this issue of Toxicologic Pathology. They are available as downloadable text files at http://taylorandfrancis.metapress.com/openurl.asp?genre=journal&issn=0192-6233. To access them, click on the issue link for 30(4), then select this article. A download option appears at the bottom of this abstract. In order to access the full article online, you must either have an individual subscription or a member subscription accessed through www.toxpath.org.
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Johnson PR, White JD. Condensation of crotonic and tiglic acid dianions with aldehydes and ketones. J Org Chem 2002. [DOI: 10.1021/jo00197a019] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Johnson PR, Barnes HM, McElvain SM. Ketene Acetals. IV. Polymers of Ketene Diethylacetal1. J Am Chem Soc 2002. [DOI: 10.1021/ja01861a071] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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McElvain SM, Bright RD, Johnson PR. The Constituents of the Volatile Oil of Catnip. I. Nepetalic Acid, Nepetalactone and Related Compounds. J Am Chem Soc 2002. [DOI: 10.1021/ja01851a019] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Koelsch CF, Johnson PR. The Action of Methylmagnesium Iodide on Methyl α-Phenylcinnamate and a Synthesis of 1,1-Dimethyl-2-phenylindene. J Am Chem Soc 2002. [DOI: 10.1021/ja01244a020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gardner S, Johnson PR. Sexual harassment in healthcare: strategies for employers. Hosp Top 2002; 79:5-11. [PMID: 11942090 DOI: 10.1080/00185860109597912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Voronina S, Sukhomlin T, Johnson PR, Erdemli G, Petersen OH, Tepikin A. Correlation of NADH and Ca2+ signals in mouse pancreatic acinar cells. J Physiol 2002; 539:41-52. [PMID: 11850500 PMCID: PMC2290122 DOI: 10.1113/jphysiol.2001.013134] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Relationships between calcium signals and NADH responses were investigated in pancreatic acinar cells stimulated with calcium-releasing secretagogues. Cytosolic calcium signals were studied using Fura Red or calcium-sensitive Cl(-) current. Mitochondrial calcium was measured using Rhod-2. The highest levels of NADH autofluorescence were found around the secretory granule region. Stimulation of cells with physiological doses of cholecystokinin (CCK) triggered slow oscillations of NADH autofluorescence. NADH oscillations were clearly resolved in the mitochondrial clusters around secretory granules. Very fast apical calcium signals induced by acetylcholine (ACh) produced no detectable changes in NADH; slightly more extended apical (or preferentially apical) calcium transients triggered clear NADH responses. Triple combined recordings of cytosolic calcium, mitochondrial calcium and NADH revealed the sequence of development of individual signals: an increase in cytosolic calcium was accompanied by a slower mitochondrial calcium response followed by a delayed increase in NADH fluorescence. Recovery of cytosolic calcium was faster than recovery of mitochondrial calcium. NADH recovery occurred at elevated mitochondrial calcium levels. During the transient cytosolic calcium oscillations induced by intermediate doses of ACh, there was an initial increase in NADH fluorescence following the first calcium transient; each of the subsequent calcium responses produced biphasic NADH changes comprising an initial small decline followed by restoration to an elevated calcium level. During the higher-frequency sinusoidal calcium oscillations induced by higher doses of ACh, NADH responses fused into a smooth rise followed by a slow decline. Supramaximal doses of ACh and CCK produced single large NADH transients.
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Chambers LS, Black JL, Poronnik P, Johnson PR. Functional effects of protease-activated receptor-2 stimulation on human airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2001; 281:L1369-78. [PMID: 11704532 DOI: 10.1152/ajplung.2001.281.6.l1369] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The protease-activated receptor (PAR)-2 is present on the smooth muscle and epithelium of human airways and can be activated by mast cell tryptase, trypsin, or the PAR-2 activating peptide (AP). Trypsin and the PAR-2 AP induced contractions in human isolated airways, and these contractions were potentiated in the presence of the cyclooxygenase (COX) inhibitor indomethacin. Trypsin also increased the contractions to histamine in airways from sensitized (allergic) patients but not from nonsensitized (nonallergic) patients. Tryptase purified from human lung, skin and lung recombinant beta-tryptases, trypsin, and the PAR-2 AP all increased DNA synthesis in human airway smooth muscle (HASM) cells. Activation of PAR-2 by tryptase, trypsin, and the PAR-2 AP did not induce PGE(2) release from HASM cells. Trypsin and the PAR-2 AP increased the levels of intracellular calcium in HASM cells, with desensitization evident after treatment with either agonist. In conclusion, activation of PAR-2 can induce contractions of human airways, potentiate contractions to histamine, and induce proliferation and therefore may contribute to airway diseases such as asthma.
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Tillmanns TD, Kamelle SA, Abudayyeh I, McMeekin SD, Gold MA, Korkos TG, Johnson PR. Panniculectomy with simultaneous gynecologic oncology surgery. Gynecol Oncol 2001; 83:518-22. [PMID: 11733965 DOI: 10.1006/gyno.2001.6414] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The objective was to report the utility and morbidity of panniculectomy in obese gynecologic oncology patients undergoing exploratory laparotomy. METHODS A retrospective chart review of 41 consecutive women who had a panniculectomy as part of an abdominal gynecologic oncology procedure between July 1996 and May 2000 was performed. Obese patients possessing a large pannus, the majority with a BMI > or = 30 kg/m(2), were included. Demographic, preoperative, operative, and postoperative data were obtained. Statistical analyses were performed using Statistical Analysis System (SAS) Version 6.13. RESULTS Panniculectomy was performed on 41 patients with a mean age of 55, weight of 126 kg, and BMI of 48 kg/m(2). The most common comorbidities in this population were hypertension, diabetes, and osteoarthritis. Wound infection occurred in 4 (9.8%) patients; 88% of the patients received a hysterectomy. The average EBL was 358 cc. Operative time and length of hospital stay were on average 203 min and 5.5 days, respectively. A prior history of diabetes increased the risk of early complications (P = 0.03). Late complications were more likely to occur in older women (P = 0.05). Wound complications were increased in patients with larger BMI's (P = 0.05). CONCLUSIONS This study supports the safety of the panniculectomy procedure in this high-risk group of morbidly obese patients for whom a technical advantage may be achieved by improved operative exposure.
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Black JL, Roth M, Lee J, Carlin S, Johnson PR. Mechanisms of airway remodeling. Airway smooth muscle. Am J Respir Crit Care Med 2001; 164:S63-6. [PMID: 11734469 DOI: 10.1164/ajrccm.164.supplement_2.2106059] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The airway smooth muscle cell can contract; relax; participate in allergic and inflammatory responses by expressing adhesion molecules, releasing cytokines, and producing matrix proteins and proteases; and, as has been reported, undergo migration. These properties enable the muscle cell to be a key component in the airway wall remodeling that accompanies persistent asthma. Evidence is emerging that identifies the pivotal steps in the signal transduction pathways that lead to the excessive proliferation of the muscle observed in vitro in airway smooth muscle cells from subjects with asthma. The contractile, biochemical, and growth characteristics of muscle from allergic subjects are different from those of nonallergic subjects. In addition, the allergic response impacts on the extracellular matrix in which the muscle is embedded, by altering the profile of matrix proteins released. Once the relationships between allergy and inflammation of the smooth muscle and its extracellular matrix are better defined, opportunities to prevent or reverse airway remodeling will become available.
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Johnson PR. Selective nontreatment and spina bifida: a case study in ethical theory and application. BIOETHICS QUARTERLY 2001; 3:91-111. [PMID: 11645467 DOI: 10.1007/bf00922548] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Sukkar MB, Hughes JM, Armour CL, Johnson PR. Tumour necrosis factor-alpha potentiates contraction of human bronchus in vitro. Respirology 2001; 6:199-203. [PMID: 11555377 DOI: 10.1046/j.1440-1843.2001.00334.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Chronic inflammation of the airways is an important component in the induction of airway hyperresponsiveness (AHR) in asthma. The pro-inflammatory cytokines interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) have been implicated in the induction of AHR. Whether these cytokines directly modulate the contractile properties of human airway smooth muscle (ASM) has not been fully investigated. METHODOLOGY The contractile response to acetylcholine (ACh) (10(-8) to 10(-3) mol/L) was determined in isolated human bronchial segments both prior to and following a 16-h incubation period with IL-1beta (10 or 20 ng/mL) and TNF-alpha (25 ng/mL), either alone or in combination. Incubation of human bronchial segments with IL-1beta/TNF-alpha was also performed in the presence of the COX-1/COX-2 inhibitor, indomethacin. RESULTS Tumour necrosis factor-alpha potentiated the contractile response to ACh by approximately 27%, while IL-1beta or the cytokines in combination had no effect. Indomethacin had no modulatory effect on the contractile response to ACh in the cytokine-treated tissues. CONCLUSIONS The relative concentrations of IL-1beta/TNF-alpha in the vicinity of ASM may ultimately determine their effects on ASM contraction in asthma.
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Clark KR, Johnson PR. Gene delivery of vaccines for infectious disease. CURRENT OPINION IN MOLECULAR THERAPEUTICS 2001; 3:375-84. [PMID: 11525561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Genetic immunization is the process of delivering and expressing a gene (or therapeutic nucleic acid) encoding a pathogen-derived antigen into target host cells to elicit a protective humoral or cell-mediated immune response. Gene delivery methods to achieve this goal have expanded rapidly, and currently employ a variety of oligonucleotides, synthetic polypeptides, recombinant vectors and even edible plants, all of which have been shown to be capable of inducing protective immunity in experimental animal models. This review highlights recent progress in several gene delivery systems (both non-viral and viral methods) using novel in vivo approaches to engender effective host immune responses against the introduced antigen.
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Johnson PR, Roth M, Tamm M, Hughes M, Ge Q, King G, Burgess JK, Black JL. Airway smooth muscle cell proliferation is increased in asthma. Am J Respir Crit Care Med 2001; 164:474-7. [PMID: 11500353 DOI: 10.1164/ajrccm.164.3.2010109] [Citation(s) in RCA: 382] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Increased airway smooth muscle (ASM) within the bronchial wall of asthmatic patients has been well documented and is likely to be the result of increased muscle proliferation. We have for the first time been able to culture ASM cells from asthmatic patients and to compare their proliferation rate with that of nonasthmatic patients. Asthmatic ASM cell cultures (n = 12) were established from explanted lungs and endobronchial biopsies. Nonasthmatic ASM cells (n = 10) were obtained from explanted tissue from patients with no airway disease, emphysema, carcinoma, and fibrosing alveolitis. Cell counts, tritiated thymidine incorporation, and cell cycle analysis were conducted over 7 d. Asthmatic ASM cell numbers at Days 3, 5, and 7 were significantly higher than corresponding values for nonasthmatic cells (p < 0.05). Tritiated thymidine incorporation was increased 3.2-fold in asthmatic cells compared with nonasthmatic cells within the first 24 h (p = 0.026). Flow cytometric analysis of DNA content on Days 1 and 2 revealed that a significantly greater percentage of asthmatic ASM cells were in the G2 + M phase (p < 0.05). This study shows for the first time that proliferation of ASM cells is increased in patients with asthma and provides evidence for an intrinsic abnormality in the ASM cell in this disease. KEYWORDS asthma; human airway smooth muscle; cell culture; cell proliferation; hyperplasia
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Lee JH, Johnson PR, Roth M, Hunt NH, Black JL. ERK activation and mitogenesis in human airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 2001; 280:L1019-29. [PMID: 11290527 DOI: 10.1152/ajplung.2001.280.5.l1019] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Asthmatic airways are characterized by an increase in smooth muscle mass, due mainly to hyperplasia. Many studies suggest that extracellular signal-regulated kinases 1 and 2 (ERK1 and ERK2, respectively), one group of the mitogen-activated protein (MAP) kinase superfamily, play a key role in the signal transduction pathway leading to cell proliferation. PGE(2) and forskolin inhibited mitogen-induced ERK activation. Inhibition of MAP kinase kinases 1 and 2 (MEK1 and MEK2, respectively), which are upstream from ERK, with the specific MEK inhibitor U-0126 blocked both cell proliferation and ERK activation. In addition, U-0126 inhibited mitogen-induced activation of p90 ribosomal S6 kinase and expression of c-Fos and cyclin D1, all of which are downstream from ERK in the signaling cascade that leads to cell proliferation. Antisense oligodeoxynucleotides directed to ERK1 and -2 mRNAs reduced ERK protein and cell proliferation. These results indicate that ERK is required for human airway smooth muscle cell proliferation. Thus targeting the control of ERK activation may provide a new therapeutic approach for hyperplasia seen in asthma.
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Johnson PR. Role of human airway smooth muscle in altered extracellular matrix production in asthma. Clin Exp Pharmacol Physiol 2001; 28:233-6. [PMID: 11236132 DOI: 10.1046/j.1440-1681.2001.03426.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. The underlying abnormality in asthma is not fully understood; however, inflammation, airway remodelling and bronchial hyperresponsiveness are key factors. The plasma exudate from the microvascular leakage plays a significant role in remodelling, which includes extracellular matrix (ECM) protein deposition/breakdown and airway smooth muscle (ASM) hyperplasia/hypertrophy. 2. The ECM is an intricate network of macromolecules that forms the 'scaffolding' of the airways. This scaffolding not only acts as mechanical support that plays a crucial role in the maintenance of airway function and structure, but it is also a dynamic and complex network that has the potential to influence cellular function, including migration, differentiation and proliferation of a number of cell types. 3. In asthmatic airways, the profile of ECM proteins is altered. The deposition of collagen I, III, V, fibronectin, tenascin, hyaluronan, versican and laminin alpha2/beta2 is increased, whereas the deposition of collagen IV and elastin is decreased. 4. This imbalance in the ECM profile within the asthmatic airway could be due to: (i) increased de novo synthesis of ECM proteins; (ii) decreased activity of its degrading enzymes, namely matrix metalloproteinases (MMP); or (iii) upregulation of the tissue-specific inhibitors of metalloproteinases (TIMP). 5. One of the characteristic features of asthma is an increase in the amount of ASM within the airways. The ECM proteins/MMP/TIMP in and around the smooth muscle may play a contributory role in this increased growth. 6. The role of current asthma treatments in the prevention or reversal of airway ECM changes is an area that has only recently become of interest, with the majority of the in vivo work focusing on the effects of corticosteroids. 7. The evidence presented in this review indicates that the ASM may influence its own environment/proliferation through the production of ECM proteins, MMP and TIMP. Further studies are needed to fully understand the role of the ASM in the production of ECM proteins, MMP and TIMP andtheir potential influence in the mechanisms underlying asthma.
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Black JL, Johnson PR, Armour CL. Factors controlling transduction signaling and proliferation of airway smooth muscle. Curr Allergy Asthma Rep 2001; 1:116-21. [PMID: 11899293 DOI: 10.1007/s11882-001-0078-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The airway smooth muscle cell is an active participant in the inflammatory response that accompanies asthma. It can interact with the epithelium and inflammatory cells to produce cytokines and cell surface molecule upregulation. Moreover, smooth muscle cells can alter the composition of the extracellular matrix proteins via changes in the production of matrix metalloproteinases and their tissue inhibitors. These properties may contribute to the increase in the amount of airway smooth muscle that characterizes the asthmatic airway wall and the remodeling that underlies the structural changes that lead to persistent asthma.
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Horton YM, Johnson PR. Trisomy 14 in myeloid malignancies: report of two cases and review of the literature. CANCER GENETICS AND CYTOGENETICS 2001; 124:172-4. [PMID: 11172913 DOI: 10.1016/s0165-4608(00)00345-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To our knowledge, 58 cases of trisomy 14 in association with hematological malignancies have been reported, predominantly in myeloid malignancies. We report two patients with trisomy 14 associated with myelodysplasia. The bone marrow showed trilineage dysplasia, monocytosis and only mild thrombocytopenia. A nonmosaic karyotype was seen in both patients and survival from diagnosis was short (<1 year). The features are consistent with data from other published cases and support the hypothesis that trisomy 14 is a non-random karyotypic abnormality, with defined clinical associations and a poor prognosis.
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MESH Headings
- Aged
- Anemia, Refractory, with Excess of Blasts/genetics
- Anemia, Refractory, with Excess of Blasts/pathology
- Anemia, Refractory, with Excess of Blasts/therapy
- Bone Marrow Cells/pathology
- Chromosomes, Human, Pair 14
- Humans
- Leukemia, Myelomonocytic, Chronic/genetics
- Leukemia, Myelomonocytic, Chronic/pathology
- Leukemia, Myelomonocytic, Chronic/therapy
- Male
- Trisomy
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Johnson PR, Black JL, Carlin S, Ge Q, Underwood PA. The production of extracellular matrix proteins by human passively sensitized airway smooth-muscle cells in culture: the effect of beclomethasone. Am J Respir Crit Care Med 2000; 162:2145-51. [PMID: 11112129 DOI: 10.1164/ajrccm.162.6.9909111] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Airway remodeling is a key feature of persistent asthma. Part of the remodeling process involves the laying down of extracellular matrix (ECM) proteins within the airways. In this study we compared the production of ECM proteins by human airway smooth-muscle (ASM) cells in culture after exposure to 10% serum from an asthmatic individual or 10% serum from a nonasthmatic individual with or without beclomethasone (0.01 to 100 nM). Enzyme-linked immunosorbent assays were done with antibodies to human fibronectin; perlecan; elastin; the laminin beta(1), gamma(1), beta(2), alpha(1) chains; thrombospondin; chondroitin sulfate; collagen types I, III, IV, and V; versican; and decorin. Serum from the asthmatic individual, when compared with that from the nonasthmatic individual, caused a significant increase in the production of fibronectin, perlecan, laminin gamma(1), and chondroitin sulfate. Beclomethasone caused a significant reduction in the number of cells exposed to serum from either the asthmatic or nonasthmatic individual, but did not reverse the increase in ECM protein induced by the former. These results suggest an interaction between the ASM and the allergic process that may alter components of the airway wall in asthma, and that corticosteroids may not prevent the fibrosis induced by resident cells within the airways.
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McKay KO, Johnson PR, Black JL, Armour CL. Parasympathetic neurotransmission in rabbit isolated bronchus is modulated at prejunctional sites via endothelinB receptor stimulation. Respirology 2000; 5:343-53. [PMID: 11192545 DOI: 10.1111/j.1440-1843.2000.00274.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the mechanism involved in endothelin-induced potentiation of the response to parasympathetic nerve stimulation. METHODOLOGY We used autoradiographic and functional studies in rabbit isolated bronchi. RESULTS Autoradiography revealed dense binding sites for radiolabelled endothelin-3 over bronchial parasympathetic ganglia. The contractile response of the bronchus to electrical field stimulation was significantly potentiated by endothelin-3, endothelin-1, sarafotoxin S6c and BQ-3020 to 326+/-53%, 293+/-63%, 514+/-119% and 655+/-178%, respectively, of control values. The endothelin-3-induced potentiation of neurally evoked responses was not affected by the presence of propranolol, phentolamine or hexamethonium. The potentiation was also unaltered by pretreatment with the endothelinA receptor antagonist BQ-123 (3 micromol/L), but was significantly reduced in the presence of the combined endothelinA/endothelinB receptor antagonist PD 145065, indicating that the potentiation was mediated via endothelinB receptors. Confirmation of endothelinB receptor involvement in the neuropotentiation was obtained by demonstration of a significant amelioration of the potentiation in the presence of the endothelinB receptor selective antagonist BQ-788, and after endothelinB receptor desensitization by the endothelin, receptor selective agonist sarafotoxin S6b. CONCLUSIONS These results suggest that the endothelin-induced potentiation of parasympathetic neural responses in the rabbit bronchus is mediated via endothelinB receptor activation.
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Abstract
Both pancreatic cysts and pancreatic tumors rarely occur in childhood. However, when encountered they can present a diagnostic and therapeutic challenge to the pediatric surgeon. The aim of this review is to discuss the different types of pancreatic cysts and tumours that may be encountered in the pediatric population, to note the modes available for their diagnosis, and to outline treatment options.
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